[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fxLN3MUwXCdr5RPjwZYIDpOj8CHyjOmngWTgoKXPtZbg":3,"$f70RWbN5AG5qIomb0q9gjaTXDmz6bvCDi3E103P8milU":36,"$f3Ft0rKFJHppdzE-vuveecxx1BUcg9iOlMLtyzf_MJDg":216,"$fucxFBm2ZjZfGSdmdRaSNGBI_F0jJme4f0GTvzUhQfL8":280},[4,8,12,16,20,24,28,32],{"title":5,"slug":6,"path":7},"About Microbeonline.com","about-microbeonline-com","\u002Fabout-microbeonline-com\u002F",{"title":9,"slug":10,"path":11},"About Me","about-me","\u002Fabout-microbeonline-com\u002Fabout-me\u002F",{"title":13,"slug":14,"path":15},"Advertise with Us","advertise-us","\u002Fadvertise-us\u002F",{"title":17,"slug":18,"path":19},"Privacy Policy","privacy-policy","\u002Fprivacy-policy\u002F",{"title":21,"slug":22,"path":23},"Authors","authors","\u002Fauthors\u002F",{"title":25,"slug":26,"path":27},"Microbes","microbes","\u002Fmicrobes\u002F",{"title":29,"slug":30,"path":31},"Books","recommended-books","\u002Frecommended-books\u002F",{"title":33,"slug":34,"path":35},"Tags","tags","\u002Ftags\u002F",{"type":37,"data":38},"blog",{"slug":39,"title":40,"description":41,"seoTitle":42,"seoDescription":42,"author":43,"createdDate":44,"lastUpdatedDate":45,"draft":46,"category":47,"image":42,"body":48,"faq":49,"commentsClosed":46,"tags":59,"related":61,"comments":212},"alkaline-peptone-water-apw-principle-preparation-uses","Alkaline Peptone Water (APW): Composition, Principle, Preparation, and Uses in Vibrio Enrichment","Alkaline Peptone Water (APW) is the standard enrichment broth for Vibrio cholerae isolation. Learn its pH selectivity principle, why vibrios form a pellicle at the surface, how to subculture onto TCBS agar, and when APW is used versus Cary-Blair transport medium.",null,"Acharya Tankeshwar","2016-09-10","2026-07-05",false,"culture-media","During a cholera outbreak in a flood-affected district, a community health worker collects rectal swabs from five household contacts of a confirmed cholera case. None of them have symptoms — these are potential asymptomatic carriers. Their stool burden of *Vibrio cholerae*, if present, will be far lower than in an acute case shedding billions of organisms per milliliter of rice-water stool.\n\nDirect plating onto TCBS agar from a low-count specimen risks a false-negative result — the few vibrio colonies present may be completely masked by residual coliform growth on the plate. The solution is a pre-enrichment step: inoculating the swab into Alkaline Peptone Water and incubating for 6–8 hours before TCBS plating. In that window, *V. cholerae* — adapted to alkaline environments — multiplies rapidly at the surface of the broth while competing intestinal flora are suppressed by the pH, giving the organism a decisive numerical advantage before any solid medium is used.\n\n**Overview**\n\nAlkaline peptone water (APW) is recommended as an enrichment broth for isolating [*Vibrio cholerae*](https:\u002F\u002Fmicrobeonline.com\u002Fvibrio-cholerae-laboratory-diagnosis-confirmation\u002F) from clinical and non-clinical samples (suspected food & water samples). Many broth media have been described for the enrichment of *V. cholerae,* including Monsur’s enrichment medium and modification of APW with added potassium tellurite. Still, they may not offer a selective advantage over APW if used with a short incubation time (6 to 8 hours).\n\n> Enrichment media are liquid culture media which contain substances that inhibit the growth of unwanted organisms.\n\n**Enrichment broth should always be used with**\n\n![Procedure for recovery of Vibrio cholerae O1 from fecal sample - Procedure for recovery ofVibrio choleraeO1 from a fecal sample](https:\u002F\u002Fassets.microbeonline.com\u002Fblogs\u002Fvibrio-cholerae-recovery-procedure.jpg)Figure: Procedure for recovery ofVibrio choleraeO1 from a fecal sample\n\n1. convalescent patients,\n2. suspected asymptomatic infections,\n3. environmental specimens, and\n4. whenever high numbers of competing organisms are likely to present in the specimen.\n\nbut when the patient is in the very early stages of illness and is passing liquid stool, it may not be necessary to enrich stool specimens.\n\n## Principle\n\nAPW achieves its selective enrichment through two mechanisms acting simultaneously:\n\n**1. Alkaline pH (8.6–9.0) — selective suppression of competing flora:** Most intestinal commensal bacteria — *Escherichia coli*, enterococci, *Bacteroides*, and other normal colonic flora — grow optimally at pH 7.0–7.4 and are significantly inhibited at pH 8.6–9.0. *Vibrio cholerae* is physiologically adapted to alkaline environments, reflecting its natural habitat in coastal waters, estuaries, and river systems at pH 8.0–9.6. This pH difference is the primary selective mechanism: APW creates an environment that is hostile to most commensals while being optimal for *Vibrio* growth.\n\n**2. Rapid Vibrio growth kinetics — enrichment by outcompeting:** *V. cholerae* has an exceptionally short generation time of approximately 18–20 minutes under optimal conditions. In APW at 37°C, it multiplies so rapidly that it reaches detectable concentrations (>10⁵ CFU\u002FmL) within 4–6 hours even from a very small initial inoculum. By the 6–8 hour subculture timepoint, *V. cholerae* will outnumber most surviving commensals by orders of magnitude.\n\n**The pellicle — biology of the surface growth pattern:** After 6–8 hours of incubation, *V. cholerae* forms a thin film called a pellicle at the surface of the APW broth. This occurs because *V. cholerae* is both **motile** (single polar flagellum) and **aerophilic** (preferring oxygenated environments) — it actively swims toward the air-liquid interface where oxygen concentration is highest. Competing organisms that survive the alkaline pH but lack this directed motility settle toward the bottom of the tube.\n\nThis biology directly determines the subculture technique: **always inoculate TCBS from the surface pellicle only, without shaking or mixing the broth.** Mixing disrupts the spatial separation between the surface-enriched *Vibrio* and the sediment of competing organisms, reducing the sensitivity of the enrichment step.\n\n**When enrichment is and is not needed:**\n\n| Clinical situation | Use APW enrichment? | Reason |\n| --- | --- | --- |\n| Acute cholera — profuse rice-water stool | Not essential | Very high organism count; direct TCBS plating sufficient |\n| Convalescent patient (illness >5 days) | **Yes** | Shedding decreasing; enrichment required to detect low counts |\n| Asymptomatic carrier | **Yes** | Low organism burden; direct plating will miss |\n| Environmental water\u002Ffood sample | **Yes** | Very low count in most samples; enrichment mandatory |\n| Rectal swab (rather than fresh stool) | **Yes** | Lower organism transfer than liquid stool |\n\n## Composition of Alkaline Peptone Water\n\n| Ingredient | Amount (g\u002FL) | Function |\n| --- | --- | --- |\n| Peptone | 10.0 | Nitrogen source — provides amino acids for bacterial growth; deliberately minimal to allow growth without excessive competing flora multiplication |\n| Sodium chloride | 10.0 | Osmotic balance — also reflects *Vibrio*'s halophilic nature; 1% NaCl supports Vibrio growth and metabolism |\n| Distilled water | 1000 mL | Diluent |\n\n**Final pH:** 8.6 ± 0.2 at 25°C (adjusted with 1 mol\u002FL sodium hydroxide)\n\n> **Why only two ingredients?** APW's simplicity is deliberate. It contains exactly enough nutrition to support rapid *Vibrio* growth but not enough to sustain the complex nutritional requirements of slower-growing commensals at alkaline pH. The alkaline pH does the selecting; the minimal peptone does the supporting. Adding enrichments (blood, serum, growth factors) would defeat the selective purpose.\n\n> **Note on halophily:** *V. cholerae* O1 and O139 are moderately halophilic — they require sodium chloride for optimal membrane function and growth. The 1% NaCl in APW is not just osmotic balance; it is a nutritional requirement that further selects for *Vibrio* over many non-halophilic intestinal flora.\n\n## Preparation of Alkaline Peptone Water\n\n1. To make about 50 bottles (i.e. 500 ml), you will need 5 g of peptone and 5 g of Sodium chloride.\n2. Dissolve the peptone and sodium chloride in the water.\n3. Adjust the reaction of the medium to pH 8.6 to 9.0 using 1 mol\u002FL sodium hydroxide.\n4. Dispense the medium in 10 ml amounts in screw-cap bottles.\n5. Sterilize by [autoclaving](\u002Fautoclave-principle-procedure-types-and-uses\u002F) (with caps loosened) at 121°C for 15 minutes. Tighten the bottle caps after the medium has cooled.\n6. Date the medium and give it a batch number. Label the bottles and record on each the expiry date of the medium (2 years from preparation).\n7. Store in a cool dark place with the bottle caps screwed tightly to prevent a change in pH.\n\n![Alkaline peptone water (apw) bottle - Alkaline peptone water (apw) bottle](https:\u002F\u002Fassets.microbeonline.com\u002Fblogs\u002FAPW-Alkaline-Peptone-Water.jpg)Figure: Alkaline peptone water (apw) bottle\n\n**pH of the medium** (pH 8.6 ± 0.2 @ 25°C)\n\n**Shelf-life:** Up to 2 years providing there is no change in the volume or appearance of the medium suggesting contamination.\n\n## Uses\n\n- Alkaline peptone water (APW) is an enrichment medium for *Vibrio cholerae*. Its alkalinity suppresses the growth of intestinal commensals, and *V.cholerae* grows rapidly. Prior enrichment in APW is unnecessary if the sample contains many vibrios (e.g., acute cholera).\n- APW is a **useful transport medium for *Vibrio cholerae***. APW is an excellent transport and enrichment medium for *V. cholerae* but unsuitable for other enteric pathogens.\n\n## APW vs Cary-Blair: Two Different Tools for Different Problems\n\nAPW and Cary-Blair are both used in cholera specimen management, but they serve entirely different purposes and must not be confused or used interchangeably.\n\n| Feature | Alkaline Peptone Water (APW) | [Cary-Blair Transport Medium](https:\u002F\u002Fmicrobeonline.com\u002Fcary-blair-transport-medium-composition-preparation-uses\u002F) |\n| --- | --- | --- |\n| Primary function | **Enrichment** — multiplies *Vibrio* before plating | **Transport** — preserves all enteric pathogens without multiplication |\n| Physical state | Liquid broth | Semisolid (0.5% agar) |\n| Organisms supported | *Vibrio cholerae* specifically | *Vibrio*, *Salmonella*, *Shigella*, *Campylobacter*, *E. coli* O157:H7 |\n| Effect on *Shigella* \u002F *Salmonella* | **Inhibits** — alkaline pH and growth kinetics suppress these organisms | **Preserves** — neutral-alkaline pH and minimal nutrients maintain viability |\n| Time window | Subculture at 6–8 hours; beyond 18 hours *Proteus* overgrowth occurs | Up to 48 hours for most organisms; several days for *Vibrio* |\n| When to use | After specimen arrives in lab; before TCBS plating for low-count specimens | During specimen collection and transport to the laboratory |\n| Can it replace the other? | **No** — APW transport >8 hours allows *Proteus* overgrowth | **No** — Cary-Blair does not enrich; direct TCBS plating from Cary-Blair may miss low counts |\n\n**The correct workflow combining both:**\n\n> Field collection → **Cary-Blair** (transport to lab) → Lab receipt → Inoculate **APW** → 6–8 hrs incubation → Surface subculture to **TCBS** → 18–24 hrs incubation → Read colonies\n\n**When Cary-Blair is unavailable:** APW may be used for transport, but only if the specimen will reach the laboratory and be subcultured within **6–8 hours** of collection. Beyond this window, *Proteus* species (which are also alkaline-tolerant) begin to overgrow, and the enrichment advantage for *Vibrio* is lost. If >8-hour transport is anticipated and Cary-Blair is unavailable, the specimen should be refrigerated to slow all bacterial growth rather than being placed in APW.\n\n## Inoculation\n\nAPW can be inoculated with liquid stool, fecal suspension, or a rectal swab.\n\n**A. For use as an enrichment medium:**\n\n1. Inoculate the APW bottle with a specimen *(The stool inoculums should not exceed 10% of the volume of the broth)*\n2. Incubate the tube with the cap loosened at 35°C to 37°C for 6 to 8 hours.\n3. After 6 to 8 hours of incubation, subcultures to **TCBS** should be made with one to two loopful of APW from the surface and topmost portion of the broth, since vibrios preferentially grow in this area.\n4. Do not shake or mix the tube before subculturing.\n5. If the broth cannot be subcultured after 6 to 8 hours of incubation, subculture at 18 hours to a fresh tube of APW.\n6. This second tube should be subcultured to a solid medium after 6 to 8 hours of incubation.\n\n**B. For use as a transport medium**\n\n1. When cholera is suspected, transfer about 1 ml of the specimen into 10 ml of sterile alkaline peptone water.\n2. The inoculated medium should reach the laboratory within 8 hours of collection (*Proteus* species will grow eventually in alkaline peptone water.)\n\n**Important limitation — APW is Vibrio-specific:** APW is optimised exclusively for *Vibrio cholerae*. Its highly alkaline pH (8.6–9.0) inhibits *Salmonella*, *Shigella*, *Campylobacter*, and virtually all other enteric pathogens. A specimen inoculated into APW for transport will lose all non-Vibrio enteric pathogens within hours. If a specimen must be transported for a broad enteric workup — not just cholera — use **Cary-Blair transport medium**, not APW.\n\n## Growth and further processing\n\n*Vibrio cholerae* grows rapidly on APW, producing turbidity on and just below the surface of the medium within 4-6 hours. To confirm that the organisms are vibrios, examine a wet preparation\u002F perform [**hanging drop motility test**](https:\u002F\u002Fmicrobeonline.com\u002Fprocedure-hanging-drop-method-test-bacterial-motility\u002F), prepare **gram stain of the smear** (which may show gram-negative curved bacilli) and\u002For culture in the TCBS medium.\n\nIf the test for detecting *Vibrio cholerae* lipopolysaccharide antigen in the stool sample is done after enrichment in APW, its sensitivity and specificity increase.\n\n## How to Remember\n\n**APW = alkaline + peptone + water — three words, three functions:**\n\n- **Alkaline** (pH 8.6–9.0) → suppresses intestinal commensals; optimal for *Vibrio*\n- **Peptone** → minimal nitrogen for *Vibrio* growth without enriching competing organisms\n- **Water** → liquid medium enabling rapid Vibrio multiplication and pellicle formation\n\n**The pellicle as a visible enrichment endpoint:** The appearance of a surface film (pellicle) in APW after 6–8 hours incubation is visual confirmation that *Vibrio* has grown. No pellicle does not necessarily mean no *Vibrio* — pellicle formation depends on inoculum size — but a visible pellicle is a positive sign. Always subculture from the surface regardless of whether a pellicle is visible, taking care not to disturb the bottom sediment.\n\n**The 6–8 hour window — why it closes:**\n\n- At 6–8 hours: *Vibrio* has maximally enriched relative to suppressed commensals → optimal subculture time\n- At 18 hours: *Proteus* species, which tolerate alkaline conditions, recover and begin multiplying → competitive advantage for *Vibrio* is lost\n- At 24+ hours: Multiple organisms competing; APW has lost selectivity\n\nIf the 6–8 hour window cannot be met, passage to a fresh APW tube (as described in the Inoculation section) resets the clock.\n\n**The cholera diagnostic chain — APW's position:**\n\n| Step | Medium | Purpose | Time |\n| --- | --- | --- | --- |\n| 1\\. Collection | — | Stool\u002Frectal swab collected | 0 hrs |\n| 2\\. Transport | Cary-Blair | Preserve all organisms during transport | 0–48 hrs |\n| 3\\. Enrichment | **APW** | Multiply *Vibrio*, suppress commensals | +6–8 hrs |\n| 4\\. Plating | TCBS agar | Select and differentiate *Vibrio* | +18–24 hrs |\n| 5\\. Confirmation | TSI, oxidase, serology | Confirm *V. cholerae* O1\u002FO139 | +2–4 hrs |\n\nAPW is the bridge between transport and selective plating — the step that makes the difference between detecting *Vibrio* at low counts and missing it entirely.\n\n**References and further readings:**\n\n1. Cheesbrough, M. (2006). *District Laboratory Practice in Tropical Countries, Part 2* (2nd ed.). Cambridge University Press.\n2. Centers for Disease Control and Prevention (CDC). *Laboratory Methods for the Diagnosis of Vibrio cholerae.* Atlanta: CDC. Available at: \u003Chttps:\u002F\u002Fwww.cdc.gov\u002Fcholera\u002Flaboratories.html>\n3. World Health Organization. (2004). *Manual for the Laboratory Identification and Antimicrobial Susceptibility Testing of Bacterial Pathogens of Public Health Importance in the Developing World.* Geneva: WHO.\n4. Kaper, J. B., Morris, J. G., & Levine, M. M. (1995). Cholera. *Clinical Microbiology Reviews*, 8(1), 48–86.",[50,53,56],{"question":51,"answer":52},"Why does Vibrio cholerae form a pellicle at the surface of APW, and why is only the surface subcultured onto TCBS?","V. cholerae is both motile (single polar flagellum) and aerophilic — it preferentially grows in oxygenated environments. When inoculated into APW and incubated at 37°C, V. cholerae actively swims toward the air-liquid interface where oxygen concentration is highest, accumulating there and forming a thin film called a pellicle after 4–6 hours. Competing organisms that survive the alkaline pH but lack directed motility toward the surface tend to remain distributed throughout the broth or settle to the bottom. Inoculating TCBS agar from the surface pellicle only — by touching the inoculating loop to the surface without mixing or shaking the broth — transfers V. cholerae-enriched material while leaving the sediment of competing organisms behind. Mixing the broth before subculture defeats the purpose of this spatial separation and reduces the sensitivity of the enrichment step.",{"question":54,"answer":55},"Why is APW suitable for Vibrio enrichment but unsuitable for Salmonella, Shigella, or Campylobacter?","APW's selectivity is based entirely on its alkaline pH (8.6–9.0). This pH range is optimal for V. cholerae and selectively suppresses most intestinal commensals. However, it also inhibits the growth of other clinically important enteric pathogens: Salmonella and Shigella grow optimally at pH 7.0–7.4 and are significantly inhibited at pH 8.6–9.0; Campylobacter is microaerophilic and also pH-sensitive, with optimal growth at pH 6.5–7.5. If a specimen for broad enteric workup (including Salmonella, Shigella, or Campylobacter) is placed into APW for transport, these organisms will be progressively killed by the alkaline pH while V. cholerae multiplies. The specimen will arrive at the laboratory as effectively Vibrio-only material, making it impossible to detect co-infecting pathogens or to perform a comprehensive enteric culture. Cary-Blair transport medium, which is pH-neutral to mildly alkaline and contains no selective enrichment mechanism, preserves all enteric pathogens simultaneously.",{"question":57,"answer":58},"When is APW enrichment unnecessary, and why?","APW enrichment is unnecessary when the specimen contains very high numbers of V. cholerae — specifically in acute cholera during the first few days of illness. A patient with acute cholera is passing liquid 'rice-water' stool containing 10⁷ to 10⁹ V. cholerae per milliliter. At these concentrations, V. cholerae vastly outnumbers competing flora even before enrichment, and direct plating onto TCBS agar will produce abundant yellow colonies without any pre-enrichment step. Proceeding with APW enrichment in this situation delays the result by 6–8 hours unnecessarily. APW enrichment is specifically valuable for the four situations where organism counts are low: convalescent patients (illness >5 days, declining shedding), asymptomatic carriers, environmental water and food samples, and rectal swab specimens (which transfer fewer organisms than fresh liquid stool).",[60],"specimen-collection-transport",[62,84,121,137,155,190],{"slug":63,"title":64,"description":65,"seoTitle":42,"seoDescription":42,"author":43,"createdDate":66,"lastUpdatedDate":67,"draft":46,"category":68,"image":42,"faq":69,"tags":82},"vibrio-cholerae-laboratory-diagnosis-confirmation","Vibrio cholerae: Cholera, Laboratory Diagnosis, and Treatment","\u003Cp>How to confirm \u003Cem>Vibrio cholerae\u003C\u002Fem> from a diarrheal outbreak: TCBS culture, string test vs Aeromonas, serotyping O1\u002FO139, and ORS-first treatment.\u003C\u002Fp>","2013-10-23","2026-08-13","bacteriology",[70,73,76,79],{"question":71,"answer":72},"Why is oral rehydration salts (ORS) the primary treatment for cholera rather than antibiotics?","\u003Cp>Cholera kills through dehydration and electrolyte loss caused by the cholera toxin permanently activating intestinal chloride secretion. Antibiotics clear the bacterium but do not immediately reverse the toxin's effect on cells already exposed to it. ORS directly addresses the physiological problem, replacing fluid and electrolytes as they are lost. A patient who receives antibiotics without adequate rehydration will still die of dehydration.\u003C\u002Fp>",{"question":74,"answer":75},"\u003Cp>Why is the string test not used as a standalone confirmatory test for \u003Cem>V. cholerae\u003C\u002Fem>?\u003C\u002Fp>","\u003Cp>Its specificity is only approximately 70%, meaning 30% of positive string test results come from organisms other than \u003Cem>V. cholerae\u003C\u002Fem>. It is a useful rapid screening step that, combined with TCBS colony morphology and oxidase positivity, substantially raises diagnostic probability but serotyping with O1\u002FO139 antisera is required for definitive confirmation.\u003C\u002Fp>",{"question":77,"answer":78},"\u003Cp>Why do \u003Cem>V. cholerae\u003C\u002Fem> strains grow best in alkaline peptone water, and why is only the surface pellicle used for plating?\u003C\u002Fp>","\u003Cp>\u003Cem>V. cholerae\u003C\u002Fem> thrives at alkaline pH (8.5), which selectively inhibits most other gut organisms that cannot tolerate alkalinity. It is aerobic and grows preferentially at the oxygen-rich surface layer, forming a pellicle. Plating only from this surface layer concentrates V. cholerae while leaving the less-relevant deeper broth unused. Shaking the broth before plating destroys this enrichment by redistributing organisms throughout the medium.\u003C\u002Fp>",{"question":80,"answer":81},"\u003Cp>What is the difference between \u003Cem>V. cholerae\u003C\u002Fem> O1 Classical and El Tor biotypes clinically?\u003C\u002Fp>","\u003Cp>Both cause cholera clinically, but El Tor has largely replaced Classical biotype worldwide because it survives better in aquatic environments, spreads more easily, and colonizes asymptomatically more often. The ongoing 7th pandemic (since 1961) is caused entirely by El Tor. Laboratory differentiation: El Tor agglutinates chicken RBCs (Classical does not) and is resistant to polymyxin B (Classical is sensitive).\u003C\u002Fp>",[83],"gram-negative-rods",{"slug":85,"title":86,"description":87,"seoTitle":86,"seoDescription":88,"author":89,"createdDate":90,"lastUpdatedDate":91,"draft":46,"category":92,"image":42,"faq":93,"tags":118},"autoclave-principle-procedure-types-and-uses","Autoclave Sterilization: Cycles, Validation, Uses, and Failures","How steam sterilization actually works, the cycles and pressures for each load type, how to validate a run with biological and chemical indicators, what cannot be autoclaved, and the practical reasons cycles fail (trapped air, wet packs, and false-passing tape).","Understand autoclave steam sterilization cycles, loading, validation indicators, common uses, and the practical causes of wet packs and failed runs.","Nisha Rijal","2019-10-03","2026-07-29","lab-equipment",[94,97,100,103,106,109,112,115],{"question":95,"answer":96},"What is the standard autoclave temperature, pressure, and time?","121°C at 15 psi for 15-20 minutes minimum. Holding time measured from when all materials in the load reach 121°C — not just the chamber gauge.",{"question":98,"answer":99},"Why is it temperature not pressure that sterilizes?","Pressure only raises boiling point to generate 121°C steam. High temperature denatures proteins and destroys nucleic acids. Steam at 100°C (atmospheric) cannot kill bacterial endospores.",{"question":101,"answer":102},"Why must all air be removed?","Air pockets prevent steam contact. Air-steam mixtures at 15 psi reach only ~112°C — too low. Complete air removal ensures 121°C throughout the entire load.",{"question":104,"answer":105},"What biological indicator tests autoclave effectiveness?","Geobacillus stearothermophilus spores — D-value 1.5-2.5 min at 121°C. CDC recommends weekly testing. For dry heat (hot air oven): Bacillus atrophaeus spores.",{"question":107,"answer":108},"Can you autoclave liquids in sealed containers?","Never — pressure differential when cycle ends can cause explosive rupture. Always loosen caps before autoclaving.",{"question":110,"answer":111},"Why are oils and powders not sterilized by autoclave?","Oils repel steam; powders trap air — both prevent steam penetration. Use dry heat sterilization (160-170°C) where conduction-based heat penetration is independent of steam.",{"question":113,"answer":114},"What is the difference between gravity displacement and pre-vacuum autoclave?","Gravity: steam slowly pushes air out — may leave air pockets. Pre-vacuum: pump actively removes air first ensuring complete steam penetration. Required for wrapped surgical packs.",{"question":116,"answer":117},"What cycle is recommended for prion-contaminated materials?","134°C for 18 minutes (pre-vacuum) OR NaOH\u002Fhypochlorite treatment + 134°C for 1 hour. Standard 121°C cycles do not inactivate prions. Single-use instruments preferred for CJD\u002FvCJD cases.",[119,120],"sterilization-disinfection","laboratory-heating-equipment",{"slug":122,"title":123,"description":124,"seoTitle":42,"seoDescription":42,"author":43,"createdDate":44,"lastUpdatedDate":125,"draft":46,"category":47,"image":42,"faq":126,"tags":136},"cary-blair-transport-medium-composition-preparation-uses"," Cary-Blair Transport Medium: Composition, Principle, Preparation, and Uses","\u003Cp>Cary-Blair is the medium of choice for transporting enteric pathogens including \u003Cem>Vibrio cholerae,\u003C\u002Fem> \u003Cem>Salmonella, Shigella,\u003C\u002Fem> and \u003Cem>Campylobacter\u003C\u002Fem>. Learn its principle, semisolid composition, survival times for key organisms, and how it compares to Stuart's, Amies, and APW.\u003C\u002Fp>","2026-08-12",[127,130,133],{"question":128,"answer":129},"Why does Cary-Blair medium use sodium thioglycollate when other transport media do not?","\u003Cp>Sodium thioglycollate is a reducing agent that lowers the oxidation-reduction (redox) potential of Cary-Blair medium, creating a microaerobic to anaerobic microenvironment within the semisolid matrix. This is specifically important for two groups of pathogens: (1) \u003Cem>Campylobacter \u003C\u002Fem>species, which are microaerophilic and are killed by prolonged exposure to atmospheric oxygen concentrations — the reduced environment extends their viability during transport; and (2) any facultative anaerobes present in the specimen whose viability is compromised by reactive oxygen species accumulation at room temperature. Stuart's and Amies media do not contain thioglycollate, which is why they show inferior \u003Cem>Campylobacter\u003C\u002Fem> recovery compared to Cary-Blair for specimens with anticipated transport delays beyond 2 hours.\u003C\u002Fp>",{"question":131,"answer":132},"Why is Cary-Blair medium alkaline (pH 8.4), and how does this protect the specimen?","\u003Cp>The alkaline pH of 8.4 in Cary-Blair medium serves two protective functions. First, it creates conditions that specifically favor \u003Cem>Vibrio cholerae\u003C\u002Fem> survival — \u003Cem>V. cholerae\u003C\u002Fem> grows optimally at pH 8.0–9.6 and survives transport far better in alkaline than neutral conditions. This is why Cary-Blair is the medium of choice for cholera specimen transport and is superior to Stuart's and Amies media (both pH 7.3) for this specific organism. Second, the alkaline pH acts as a buffer against the metabolic acid production that would otherwise occur as organisms undergo limited metabolic activity during transport. Even minimal metabolism of substrates in the specimen produces organic acids; at pH 7.3, these acids accumulate and can drop the local pH to levels lethal to acid-sensitive organisms such as \u003Cem>Shigella.\u003C\u002Fem> The alkaline starting pH provides a substantial buffer capacity that maintains a safe pH range throughout the transport period.\u003C\u002Fp>",{"question":134,"answer":135},"How long do different enteric pathogens survive in Cary-Blair medium, and what are the practical implications?","\u003Cp>Survival times in Cary-Blair medium vary significantly by organism, which has direct implications for transport planning: \u003Cem>Salmonella\u003C\u002Fem> and \u003Cem>Shigella\u003C\u002Fem> survive for at least 48 hours and typically several days;\u003Cem> Vibrio cholerae\u003C\u002Fem> survives for at least 48 hours, with Cary-Blair's alkaline pH providing superior conditions compared to other transport media; \u003Cem>Yersinia enterocolitica\u003C\u002Fem> and \u003Cem>Y. pestis\u003C\u002Fem> survive for 48+ hours; \u003Cem>Campylobacter\u003C\u002Fem> species survive for only up to 6 hours, making same-day transport essential — specimens for \u003Cem>Campylobacter \u003C\u002Fem>culture collected in Cary-Blair must reach the laboratory within 6 hours, or be refrigerated to slow all bacterial activity. The practical implication for field collection: Cary-Blair is suitable for overnight transport for \u003Cem>Salmonella\u003C\u002Fem> and \u003Cem>Shigella\u003C\u002Fem>, but not for \u003Cem>Campylobacter\u003C\u002Fem>. If \u003Cem>Campylobacter\u003C\u002Fem> is specifically suspected and same-day transport is not possible, campy thioglycollate medium is the alternative.\u003C\u002Fp>",[60],{"slug":138,"title":139,"description":140,"seoTitle":42,"seoDescription":42,"author":43,"createdDate":141,"lastUpdatedDate":142,"draft":46,"category":68,"image":42,"faq":143,"tags":153},"procedure-hanging-drop-method-test-bacterial-motility","Hanging Drop Method: Principle, Procedure & How to Read True Motility","\u003Cp>Step-by-step hanging drop technique: how to tell true motility from Brownian movement and passive drift, plus its real use in flagging cholera and ruling out \u003Cem>Bacillus anthracis.\u003C\u002Fem>\u003C\u002Fp>","2014-08-03","2026-08-22",[144,147,150],{"question":145,"answer":146},"How do I tell true motility from Brownian movement?","\u003Cp>True motility means organisms change position relative to each other over time: purposeful, directional movement. Brownian movement is jiggling in place; the organisms stay in the same relative position to one another even though they appear to vibrate. Brownian movement appears on every slide regardless of whether the organism is motile.\u003C\u002Fp>",{"question":148,"answer":149},"\u003Cp>My drop dried out before I finished reading it, what went wrong?\u003C\u002Fp>","Almost always an incomplete petroleum-jelly seal. If the drop looks like it's shrinking or the edges look ragged partway through observation, remake the prep with a more complete seal rather than trying to interpret a drying sample.",{"question":151,"answer":152},"Can hanging drop be used to help rule out anthrax?","\u003Cp>Yes, as one early step. \u003Cem>Bacillus anthracis\u003C\u002Fem> is classically nonmotile, while closely related \u003Cem>B. cereus\u003C\u002Fem> group members are typically motile, so a quick motility check helps distinguish a concerning isolate before specialized confirmatory testing.\u003C\u002Fp>",[154],"motility-test",{"slug":156,"title":157,"description":158,"seoTitle":159,"seoDescription":42,"author":43,"createdDate":160,"lastUpdatedDate":125,"draft":46,"category":47,"image":42,"faq":161,"tags":189},"viral-transport-media-vtm","Viral Transport Media (VTM): Composition, Uses, Storage, and VTM vs UTM","What is in viral transport medium and why, how it differs from universal transport medium and bacterial media like Amies, correct storage temperatures, and the freezing mistake that destroys specimens.","Viral Transport Media (VTM): Composition, Uses, and Correct Storage","2020-03-23",[162,165,168,171,174,177,180,183,186],{"question":163,"answer":164},"What does viral transport medium contain?","A buffered balanced salt solution to hold pH and osmolality, a protein stabilizer such as serum, albumin, or gelatin to protect virions and stop them adsorbing to the tube wall, and antimicrobials (typically an antibiotic plus an antifungal) to suppress contaminating bacteria and fungi. Some formulations include phenol red as a pH indicator.",{"question":166,"answer":167},"Can I use one swab in VTM for both viral and bacterial testing?","No. VTM contains antibiotics and an antifungal specifically to prevent bacterial and fungal overgrowth, so bacteria in that specimen will be suppressed. If both viral and bacterial investigations are needed from the same site, collect two separate specimens.",{"question":169,"answer":170},"At what temperature should VTM specimens be stored?","Hold at 2 to 8°C and process within 48 to 72 hours. If processing will be delayed beyond that, freeze at -70°C or below and transport on dry ice. Room temperature is tolerated briefly during transit but is not equivalent to refrigeration.",{"question":172,"answer":173},"Why should viral specimens never be frozen at -20°C?","A -20°C freezer sits in the temperature range where ice crystals form and grow, and frost-free models repeatedly partially thaw and refreeze their contents. This shears viral envelopes and fragments nucleic acid. A specimen held at -20°C ends up in worse condition than one kept in the refrigerator. If -70°C is unavailable, refrigerate and expedite transport instead.",{"question":175,"answer":176},"What is the difference between VTM and UTM?","Universal transport medium is formulated to support viruses together with Chlamydia, Mycoplasma, and Ureaplasma, and to serve both culture and molecular testing. In practice the terms are used almost interchangeably and most commercial VTM sold today is a universal formulation. The distinction that matters at the bench is whether the medium is a viral one or a bacterial one.",{"question":178,"answer":179},"Can I use liquid Amies (eSwab) for a viral specimen?","No. Liquid Amies is a bacterial maintenance medium and lacks the protein stabilizer and antimicrobials a viral specimen requires. The two systems look nearly identical, both a flocked swab in liquid in a screw-cap tube, so check the medium named on the label rather than the appearance of the device.",{"question":181,"answer":182},"Why is VTM suitable for Chlamydia, Mycoplasma, and Ureaplasma if they are bacteria?","Because they are osmotically fragile in the same way viruses are. Chlamydia is an obligate intracellular organism, and Mycoplasma and Ureaplasma have no cell wall at all. All three die quickly in the salt-based media used for ordinary bacteria and need the protein stabilization and buffering that VTM provides.",{"question":184,"answer":185},"What is inactivating VTM and when should it be used?","Inactivating VTM contains a lysis agent that destroys the virus on contact while preserving its nucleic acid for PCR, which reduces the biohazard for anyone handling the specimen. The trade-off is absolute: culture, isolation, and any test requiring live virus become impossible. Use it when the request is molecular only, and use non-inactivating medium when culture may be needed.",{"question":187,"answer":188},"Should CSF or urine be placed in VTM?","No. Liquid specimens including cerebrospinal fluid, bronchoalveolar lavage fluid, urine, and ocular fluids are submitted neat in a sterile container. VTM exists to keep a swab from drying out and to stabilize what is on it. Adding it to a liquid specimen only dilutes the target, which costs sensitivity in specimens where viral load is often already low.",[60],{"slug":191,"title":192,"description":193,"seoTitle":42,"seoDescription":42,"author":89,"createdDate":194,"lastUpdatedDate":45,"draft":46,"category":47,"image":42,"faq":195,"tags":211},"amies-transport-medium","Amies Transport Medium: Composition, Uses, and Why It Replaced Stuart's Medium","Why a fragile gonococcus swab can die before it ever reaches the lab, the design fix that made Amies better than Stuart's medium, and when to choose the charcoal-free version instead.","2019-12-03",[196,199,202,205,208],{"question":197,"answer":198},"What is Amies transport medium used for?","Preserving swab specimens, such as throat, wound, vaginal, and genital swabs, in a stable, non-multiplying state during transport to the microbiology laboratory.",{"question":200,"answer":201},"Why did Amies medium replace Stuart's medium?","Stuart's medium used glycerophosphate as a buffer, but some organisms could use it as a carbon source and keep multiplying during transport. Amies replaced it with an inorganic phosphate buffer to remove that problem.",{"question":203,"answer":204},"When should Amies without charcoal be used instead of the charcoal version?","Specifically for Mycoplasma and Ureaplasma recovery, since charcoal, helpful for most other fastidious organisms, actually inhibits recovery of these two.",{"question":206,"answer":207},"Can Amies transport medium be frozen for longer storage?","No. Freezing causes ice crystals to rupture bacterial cells, killing the organism. Refrigeration, not freezing, is the correct way to slow deterioration during transport.",{"question":209,"answer":210},"How long can a specimen sit in Amies medium before processing?","Ideally within 6 hours, and no later than 24 hours, maintaining a cold chain throughout.",[60],{"enabled":213,"threads":214,"total":215},true,[],0,[217,223,230,237,243,248,254,259,265,268,274],{"slug":218,"name":43,"description":219,"image":220,"body":221,"postCount":222},"acharya-tankeshwar","Editor-in-chief","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Ftankeshwar-acharya-author-microbeonline.jpg","***Tankeshwar Acharya, MSc (Medical Microbiology)***\n\n*Tankeshwar Acharya is an Assistant Professor in the Department of Microbiology at Patan Academy of Health Sciences (PAHS), Nepal, where he has been teaching and practicing clinical microbiology for over 14 years. He is the founder of Microbe Online, one of the leading free microbiology education resources on the web, covering bacteriology, mycology, parasitology, immunology, and clinical laboratory diagnostics written from direct experience in both the classroom and the diagnostic laboratory.*",480,{"slug":224,"name":225,"description":226,"image":227,"body":228,"postCount":229},"ashma-shrestha","Ashma Shrestha","SEO Copywriter and Science Communicator\nKathmandu, Nepal","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fashma-shrestha.png","Ashma Shrestha holds a Master of Science in Medical Microbiology from the Institute of Science and Technology (IOST), Tribhuvan University, Nepal, where she developed a strong foundation in virology, molecular biology, and diagnostic microbiology.\n\nShe now works as an SEO Copywriter at Resolution Digital, where she combines her scientific training with research-driven content strategy. She is certified in Google Analytics and Google Business Profile (GBP), and brings a data-informed approach to science communication writing content that is not only accurate but structured to reach and serve the students who need it most.\n\nAt microbeonline, Ashma contributes articles primarily in virology and molecular biology, areas she finds most compelling for their mechanistic depth and their growing clinical relevance. Her writing reflects the same standard the site is built on: factual rigor, clear explanation of the *why* behind microbiology concepts, and content that helps students move from memorization to genuine understanding.\n\nShe is passionate about making complex microbiological concepts accessible without sacrificing accuracy; a skill that sits at the intersection of her scientific training and her professional work in content and SEO.",79,{"slug":231,"name":232,"description":233,"image":234,"body":235,"postCount":236},"sushmita-baniya","Sushmita Baniya","Author \u002F Contributor","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fsushmita-baniya-1.png","Sushmita Baniya holds an M.Sc. in Medical Microbiology from Tribhuvan University (National College), with a research focus in Genetics and Molecular Biology. She is actively involved in teaching and research in the field of microbiology.",26,{"slug":238,"name":239,"description":233,"image":240,"body":241,"postCount":242},"samikshya-acharya","Samikshya Acharya","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fsamikshya-acharya.jpeg","Samikshya Sharma completed her postgraduate studies in Medical Microbiology at the Central Department of Microbiology, Tribhuvan University, Nepal. She contributes to Microbeonline with the goal of making foundational and clinical microbiology concepts clear and useful for students in medical, laboratory science, and allied health programs.",20,{"slug":244,"name":245,"description":233,"image":42,"body":246,"postCount":247},"alisha-tripathi","Alisha Tripathi","Alisha Tripathi holds an M.Sc. in Medical Microbiology from National College, Tribhuvan University. With over a year of teaching experience, her academic interests span Molecular Biology, Immunology, and Genetics.",6,{"slug":249,"name":250,"description":251,"image":42,"body":252,"postCount":253},"aastha-shrestha","Aastha Shrestha"," Author \u002F Contributor","Aastha Shrestha is a Biotechnology graduate with an M.Sc. from National College, Tribhuvan University. Her academic interests center on Molecular Biology and Immunology; two fields that are increasingly converging in modern diagnostic and clinical microbiology. \n\nShe contributes to Microbeonline with the goal of making complex concepts in these areas approachable and exam-relevant for students across medical, biotechnology, and laboratory science programs.",9,{"slug":255,"name":256,"description":257,"image":42,"body":42,"postCount":258},"guest-author","Guest Author","Guest Author \u002F Contributor",1,{"slug":260,"name":261,"description":233,"image":262,"body":263,"postCount":264},"srijana-khanal","Srijana Khanal","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fsrijana-khanal-1.png","Srijana Khanal is a microbiology educator with nearly a decade of teaching experience, including her role as faculty in the Microbiology Department at National College, NIST. \n\nHer time in the classroom has given her a clear sense of where students struggle and what explanations actually work, a perspective that directly shapes how she writes.\n\nHer academic interests span Immunology, Genetics, Basic Sciences, and Research Methodology, and she brings the same rigor to her writing that she brought to teaching. Alongside academic writing, she has a passion for creative writing -- an instinct that shows in her ability to make dense scientific material readable without sacrificing accuracy.\n\nShe contributes to Microbeonline to extend her teaching reach beyond the classroom, helping medical and laboratory science students across the region build a stronger foundation in microbiology.",15,{"slug":266,"name":267,"description":257,"image":42,"body":42,"postCount":258},"dr-poonam-acharya","Dr. Poonam Acharya",{"slug":269,"name":89,"description":270,"image":271,"body":272,"postCount":273},"nisha-rijal","Microbiologist and AMR Specialist Kathmandu, Nepal","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fnisha-rijal-1.png","Nisha Rijal is a microbiologist with nearly 15 years of frontline diagnostic and surveillance experience at the National Public Health Laboratory (NPHL), national reference laboratory under the Department of Health Services, Nepal. She currently works as an AMR Support Officer at the World Health Organization (WHO), Nepal, where her work focuses on strengthening antimicrobial resistance surveillance systems and translating AMR data into actionable public health response.\n\nHer research, published in peer-reviewed journals and cited over 220 times, spans some of the most clinically significant infectious disease challenges in Nepal and South Asia: antimicrobial resistance trends in *Vibrio cholerae* across an 11-year national surveillance dataset, sero-epidemiology of scrub typhus in patients with acute febrile illness, lower respiratory tract infections in HIV-positive patients, and gonococcal resistance surveillance. She was a contributor to Nepal's National Antimicrobial Resistance Containment Action Plan, a foundational policy document for AMR governance in Nepal. You can find list of [Nisha Rijal's article here in Google Scholar.](https:\u002F\u002Fscholar.google.com\u002Fcitations?user=N-Ruq54AAAAJ&hl=en)\n\nThis depth of experience is visible in her writing at Microbeonline. Her 53 published articles cover bacteriology, parasitology, mycology, immunology, and laboratory techniques, and are consistently among the most detailed and clinically grounded content on the site. She brings to every article the same standard that national reference laboratory work demands: methodological precision, awareness of real diagnostic constraints, and an understanding of what results actually mean for patient care in resource-limited settings.\n\nHer areas of particular expertise include antimicrobial susceptibility testing and resistance mechanism detection, quality assurance in clinical microbiology, and laboratory-based infectious disease surveillance.\n\n---\n\n*Nisha Rijal contributes to Microbeonline in a personal capacity. Her views and writing do not represent the positions of the World Health Organization or any other institution.*",54,{"slug":275,"name":276,"description":277,"image":278,"body":279,"postCount":258},"padma-shrestha","Padma Shrestha","Author","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fpadma-shrestha.png","Padma Shrestha is from Kathmandu, Nepal. She has completed Masters degree in Medical microbiology from Tribhuvan University. She has great interest in Microbiology and Molecular Biology.",[281,288,294,299,303,308,312,316,320,325,329,334,338,342,346,350,354,358,363,368,372,376,380,385,389,393,397,401,406,411,415,419,423,428,432,435,439,443,447,451,455,459,463,467,471,475,479,483,487,491,495,499,503,507,511,515,519,523,527,531,535,539,543,547,551,555,559,563,566,570,573,576,579,582,585,588,591,594,597],{"slug":282,"name":283,"description":284,"image":285,"body":286,"postCount":287},"gram-negative-cocci","Gram-Negative Cocci and Coccobacilli","Neisseria, Moraxella, Haemophilus and related gram-negative coccal organisms","https:\u002F\u002Fassets.microbeonline.com\u002Ftags\u002Fgram-negative-cocci.png","# Gram Negative Cocci\n\nNeisseria gonorrhoeae, Neisseria meningitides, Moraxella catarrhalis, and other Neisseria spp. are clinically relevant gram-negative cocci.\n\nN. gonorrhoeae is the leading cause of sexually transmitted disease whereas N. meningitides is a leading cause of fatal bacterial meningitis.",14,{"slug":289,"name":290,"description":291,"image":42,"body":292,"postCount":293},"microscopy","Microscopy","Microscope types, components, and microscopy techniques","These are list of blog posts related to microscopy. ",12,{"slug":295,"name":296,"description":297,"image":42,"body":42,"postCount":298},"gram-positive-cocci","Gram-Positive Cocci","Staphylococcus, Streptococcus, Enterococcus, Micrococcus — organisms, diseases, and identification tests",11,{"slug":83,"name":300,"description":301,"image":42,"body":42,"postCount":302},"Gram-Negative Rods (Other than Enterobacteriaceae)","\u003Cp>Gram negative rods other than members of Enterobacteriaceae family such as  Pseudomonas, Acinetobacter and related organisms\u003C\u002Fp>",5,{"slug":304,"name":305,"description":306,"image":42,"body":42,"postCount":307},"gram-positive-rods","Gram-Positive Rods","Bacillus, Clostridium, Listeria, Corynebacterium, Actinomyces and related organisms",8,{"slug":309,"name":310,"description":311,"image":42,"body":42,"postCount":298},"mycobacteria","Mycobacteria","Mycobacterium tuberculosis, leprosy, atypical mycobacteria, and acid-fast organism diagnosis",{"slug":313,"name":314,"description":315,"image":42,"body":42,"postCount":298},"anaerobic-bacteriology","Anaerobic Bacteriology","Anaerobic organisms, anaerobic culture methods, and anaerobic infection diagnosis",{"slug":317,"name":318,"description":319,"image":42,"body":42,"postCount":293},"enterobacteriaceae","Enterobacteriaceae","Identification, differentiation, and clinical significance of Enterobacteriaceae family members",{"slug":321,"name":322,"description":323,"image":42,"body":42,"postCount":324},"spirochetes","Spirochetes","Treponema, Leptospira, Borrelia and spirochetal infections",7,{"slug":326,"name":327,"description":328,"image":42,"body":42,"postCount":264},"food-microbiology","Food Microbiology","Food-borne pathogens, food safety, spoilage, and preservation",{"slug":330,"name":331,"description":332,"image":42,"body":42,"postCount":333},"antimicrobial-susceptibility-testing","Antimicrobial Susceptibility Testing","Methods for testing antibiotic susceptibility in clinical microbiology",21,{"slug":335,"name":336,"description":337,"image":42,"body":42,"postCount":293},"antimicrobials-moa-amr","Antimicrobials (MOA & AMR)","Mechanisms, detection, and clinical significance of antimicrobial resistance",{"slug":119,"name":339,"description":340,"image":42,"body":42,"postCount":341},"Sterilization and Disinfection","Methods of sterilization and disinfection in healthcare and laboratory settings",10,{"slug":60,"name":343,"description":344,"image":42,"body":42,"postCount":345},"Specimen Collection and Transport","Collection, handling, and transport of clinical specimens for microbiological testing",27,{"slug":347,"name":348,"description":349,"image":42,"body":42,"postCount":333},"bacterial-structure-physiology","Bacterial Structure and Physiology","Bacterial cell structure, growth, physiology, and environmental factors affecting growth",{"slug":351,"name":352,"description":42,"image":42,"body":353,"postCount":247},"horizontal-gene-transfer","Horizontal Gene Transfer","Articles related to **Horizontal Gene Transfer**",{"slug":355,"name":356,"description":42,"image":42,"body":357,"postCount":341},"chromatography","Chromatography","Information about chromatographic techniques.",{"slug":359,"name":360,"description":361,"image":42,"body":362,"postCount":324},"electrophoresis","Electrophoresis","Information about Electrophoresis Techniques ","Detailed information  about Electrophoresis Techniques ",{"slug":364,"name":365,"description":366,"image":42,"body":367,"postCount":247},"pcr-techniques","PCR Techniques","Information about various types of Polymerase Chain Reaction Techniques ","More detailed information about various types of Polymerase Chain Reaction Techniques ",{"slug":369,"name":370,"description":371,"image":42,"body":42,"postCount":247},"bacteriophage","Bacteriophage","Description about Bacteriophage.",{"slug":373,"name":374,"description":375,"image":42,"body":42,"postCount":247},"malaria","Malaria","It is the collections of articles regarding malarial disease. ",{"slug":377,"name":378,"description":379,"image":42,"body":42,"postCount":247},"anaerobic-culture-techniques","Anaerobic Culture Techniques","Posts related with Anaerobic Culture Techniques.",{"slug":381,"name":382,"description":383,"image":42,"body":42,"postCount":384},"immunoassays","Immunoassays","You will get information about all the diagnostic tests that rely on the specific binding between an antigen and an antibody to detect or quantify a substance.",19,{"slug":386,"name":387,"description":388,"image":42,"body":42,"postCount":324},"biosafety-levels","Biosafety levels ","Articles related to Biosafety Levels",{"slug":390,"name":391,"description":392,"image":42,"body":42,"postCount":302},"environmental-factors","Environmental Factors ","In this case we are talking about growth requirements of microorganisms with deep dive in environmental factors that affect the growth. ",{"slug":394,"name":395,"description":396,"image":42,"body":42,"postCount":247},"pipette","Pipette","Posts related with Pipette. ",{"slug":398,"name":399,"description":400,"image":42,"body":42,"postCount":307},"bacteriology-mcqs","Bacteriology MCQs","This sections lists MCQs in Bacteriology.",{"slug":402,"name":403,"description":404,"image":42,"body":42,"postCount":405},"parasitology-mcqs","Parasitology MCQs","This section lists MCQs in Parasitology.",2,{"slug":407,"name":408,"description":409,"image":42,"body":42,"postCount":410},"virology-mcqs","Virology MCQs","This is the collections of Multiple Choice Questions in Virology.",4,{"slug":412,"name":413,"description":414,"image":42,"body":42,"postCount":302},"mcqs-in-microbiology","MCQs in Microbiology","This section lists the collections of Multiple Choice Questions in General Microbiology Topics. ",{"slug":416,"name":417,"description":418,"image":42,"body":42,"postCount":307},"immunology-mcqs","Immunology MCQs","In this section; we are posting collections of Multiple Choice Questions about Immunology. ",{"slug":420,"name":421,"description":422,"image":42,"body":42,"postCount":253},"microbial-curiosities","Microbial Curiosities","In this clusters, we are posting interesting and unique information about Microorganisms. ",{"slug":424,"name":425,"description":426,"image":42,"body":42,"postCount":427},"bacterial-culture-media","Bacterial Culture Media","Posts related to Bacterial Culture Media. ",23,{"slug":429,"name":430,"description":431,"image":42,"body":42,"postCount":247},"fungal-culture-media","Fungal Culture Media","Posts related to Fungal Culture Media.",{"slug":154,"name":433,"description":434,"image":42,"body":42,"postCount":302},"Motility Test","This lists the procedure regarding various tests methods for bacterial motility.",{"slug":436,"name":437,"description":438,"image":42,"body":42,"postCount":341},"bacterial-enumeration","Bacterial enumeration","These posts are related to isolation and enumeration of bacteria. ",{"slug":440,"name":441,"description":442,"image":42,"body":42,"postCount":405},"gram-positive-coccobacillus","Gram-positive coccobacillus","List of Gram Positive Coccobacilli",{"slug":444,"name":445,"description":446,"image":42,"body":42,"postCount":410},"dimorphic-fungi","Dimorphic Fungi","This is about various dimorphic fungi. ",{"slug":448,"name":449,"description":450,"image":42,"body":42,"postCount":324},"bacterial-classification","Bacterial Classification","These posts are related with various approaches used for the classification of Bacteria. ",{"slug":452,"name":453,"description":454,"image":42,"body":42,"postCount":302},"immunofluorescence","Immunofluorescence ","Various Tests related to Immunofluorescence ",{"slug":456,"name":457,"description":458,"image":42,"body":42,"postCount":253},"antibody-mediated-immunity","Antibody-mediated Immunity","This clusters links the articles that are sharing insights about Antibody-mediated immunity. ",{"slug":460,"name":461,"description":462,"image":42,"body":42,"postCount":324},"hypersensitivity","Hypersensitivity","Articles related to Hypersensitivity.",{"slug":464,"name":465,"description":42,"image":42,"body":42,"postCount":466},"haemophilus","Haemophilus",3,{"slug":468,"name":469,"description":470,"image":42,"body":42,"postCount":410},"sexually-transmitted-infections-stis","Sexually transmitted infections (STIs)","This is the clusters of infections that are transmitted sexually. ",{"slug":472,"name":473,"description":474,"image":42,"body":42,"postCount":293},"adaptive-immunity","Adaptive Immunity","Blog posts related to B Cell Immunity and T Cell Immunity.",{"slug":476,"name":477,"description":478,"image":42,"body":42,"postCount":287},"fungal-diagnostics","Fungal Diagnostics","Various methods used for the Diagnosis of Fungal Infections. ",{"slug":480,"name":481,"description":482,"image":42,"body":42,"postCount":302},"laboratory-storage-and-preservation","Laboratory Storage and Preservation","Articles about Laboratory Storage of Antimicrobial Disk, Test organisms and Equipment used for this process. ",{"slug":120,"name":484,"description":485,"image":42,"body":486,"postCount":247},"Laboratory Heating Equipment","A guide to laboratory heating equipment, including hot plates, water baths, Bunsen burners, incubators, and dry baths, and how to choose the right one for each task.","Laboratory heating equipment covers the instruments that warm, melt, incubate, or sterilize samples and media in a microbiology laboratory. Each one delivers heat differently. \n\nA hot plate gives high, direct, dry heat; a water bath gives gentle, even, wet heat up to about 100°C; a Bunsen burner gives an open flame for rapid, very high heat; an incubator holds cultures at a steady temperature over hours or days; and a dry bath heats small tubes without water. Choosing the right one depends on the temperature you need, how precise it must be, and whether the sample can tolerate direct or open-flame heat.\n\nThe articles below cover each piece of heating equipment in detail, including its parts, working principle, uses, and the mistakes that most often go wrong at the bench.",{"slug":488,"name":489,"description":490,"image":42,"body":42,"postCount":253},"laboratory-glassware","Laboratory Glassware","Posts about Laboratory Glassware. ",{"slug":492,"name":493,"description":494,"image":42,"body":42,"postCount":247},"helminths","Helminths","In this section, we are covering properties, life cycle, pathogenesis and laboratory diagnosis of Helminths\u002FHelminthic infestations. ",{"slug":496,"name":497,"description":498,"image":42,"body":42,"postCount":324},"protozoan-parasite","Protozoan Parasite","In this cluster, we are covering protozoan parasites. ",{"slug":500,"name":501,"description":502,"image":42,"body":42,"postCount":258},"tests-for-gram-positive-cocci","Biochemical Tests for Gram Positive Cocci","This is the lists of Biochemical Tests that are used for Gram Positive Cocci. ",{"slug":504,"name":505,"description":506,"image":42,"body":42,"postCount":341},"bacterial-staining-technique","Bacterial Staining Technique","Lists of various staining techniques that are used to stain bacteria. ",{"slug":508,"name":509,"description":510,"image":42,"body":42,"postCount":333},"enzyme-tests","Enzyme Tests","\u003Cp>Various Biochemical Test that are based on enzymatic activity of the microorganisms. \u003C\u002Fp>",{"slug":512,"name":513,"description":514,"image":42,"body":42,"postCount":298},"carbohydrate-utilization","Carbohydrate Utilization","\u003Cp>Various biochemical tests which are related to Carbohydrate fermentation or Utilization\u003C\u002Fp>",{"slug":516,"name":517,"description":518,"image":42,"body":42,"postCount":302},"susceptibility-based-id","Susceptibility-based ID","\u003Cp>These are susceptibility based identification test such as optochin sensitivity, bacitracin sensitivity etc. \u003C\u002Fp>",{"slug":520,"name":521,"description":522,"image":42,"body":42,"postCount":410},"microbial-metabolism","Microbial Metabolism","\u003Cp>Tests about Microbial Metabolism. \u003C\u002Fp>",{"slug":524,"name":525,"description":526,"image":42,"body":42,"postCount":307},"substrate-utilization","Substrate Utilization","\u003Cp>The test in which a non-sugar carbon\u002Fnitrogen source is used or degraded (citrate, malonate, decarboxylases, indole, PAD).\u003C\u002Fp>",{"slug":528,"name":529,"description":530,"image":42,"body":42,"postCount":466},"atypical-pneumonia","Atypical Pneumonia","\u003Cp>Organisms responsible for Atypical Pneumonia. \u003C\u002Fp>",{"slug":532,"name":533,"description":534,"image":42,"body":42,"postCount":302},"antigen","Antigen","\u003Cp>Various articles related to Antigens.\u003C\u002Fp>",{"slug":536,"name":537,"description":538,"image":42,"body":42,"postCount":324},"innate-immunity","Innate Immunity","\u003Cp>Articles related to Innate Immunity. \u003C\u002Fp>",{"slug":540,"name":541,"description":542,"image":42,"body":42,"postCount":410},"respiratory-tract-infection","Respiratory Tract Infection","\u003Cp>In this cluster, you can see various etiological agents that causes respiratory tract infection. \u003C\u002Fp>",{"slug":544,"name":545,"description":546,"image":42,"body":42,"postCount":302},"torch-infection","TORCH Infection","\u003Cp>In this section; you can find articles related with TOCH infection. \u003C\u002Fp>",{"slug":548,"name":549,"description":550,"image":42,"body":42,"postCount":324},"microbiology-for-beginners","Microbiology for Beginners","\u003Cp>These articles are very basic articles, which will share general concepts in Microbiology. \u003C\u002Fp>",{"slug":552,"name":553,"description":554,"image":42,"body":42,"postCount":247},"dna-replication","DNA Replication","\u003Cp>Articles related to DNA and Replication of DNA. \u003C\u002Fp>",{"slug":556,"name":557,"description":558,"image":42,"body":42,"postCount":324},"genetic-code","Genetic Code","\u003Cp>Articles related to Genetic Code.\u003C\u002Fp>",{"slug":560,"name":561,"description":562,"image":42,"body":42,"postCount":302},"molecular-technique","Molecular Technique","\u003Cp>Posts related to Molecular Techniques. \u003C\u002Fp>",{"slug":564,"name":565,"description":42,"image":42,"body":42,"postCount":258},"colorimetric-assay","Colorimetric Assay ",{"slug":567,"name":568,"description":569,"image":42,"body":42,"postCount":302},"pharmaceutical-microbiology","Pharmaceutical Microbiology","\u003Cp>Various articles related to Pharmaceutical Microbiology\u003C\u002Fp>",{"slug":571,"name":572,"description":42,"image":42,"body":42,"postCount":466},"blood-and-immune-cells","Blood and Immune Cells",{"slug":574,"name":575,"description":42,"image":42,"body":42,"postCount":302},"host-pathogen-interaction","Host Pathogen Interaction",{"slug":577,"name":578,"description":42,"image":42,"body":42,"postCount":410},"blood-culture","Blood Culture",{"slug":580,"name":581,"description":42,"image":42,"body":42,"postCount":410},"environmental-microbiology","Environmental microbiology ",{"slug":583,"name":584,"description":42,"image":42,"body":42,"postCount":247},"copromicroscopic-technique","Copromicroscopic Technique",{"slug":586,"name":587,"description":42,"image":42,"body":42,"postCount":466},"quality-control","Quality Control",{"slug":589,"name":590,"description":42,"image":42,"body":42,"postCount":410},"dermatophytes","Dermatophytes",{"slug":592,"name":593,"description":42,"image":42,"body":42,"postCount":466},"viral-hemorrhagic-fevers","Viral Hemorrhagic Fevers",{"slug":595,"name":596,"description":42,"image":42,"body":42,"postCount":410},"h2s-production","H2S Production",{"slug":598,"name":599,"description":42,"image":42,"body":42,"postCount":405},"water-quality-testing","Water Quality Testing"]