[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-398684-105":59,"doc-detail-398684-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","lab-10-biochemical-tests-procedure","Lab 10 (Biochemical Tests) - Procedure","","Lab 10 covers biochemical tests used for identifying bacterial isolates and distinguishing bacterial species based on specific enzyme activities. It explains the role of enzymes such as catalase, oxidase, coagulase, urease, and gelatinase in metabolism, oxygen tolerance, and virulence-related functions. For each test, the document presents the underlying principle and provides step-by-step procedures, including incubation conditions, reagent addition, observation criteria (color change, gas bubbles, clouding/clots, liquefaction), and result recording for presumptive identification.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":20,"@type":76,"position":81},"https://docshare.wps.com/document/exam/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/lab-10-biochemical-tests-procedure/398684/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/lab-10-biochemical-tests-procedure/398684.png","ImageObject",300,407,{"name":92,"@type":93},"Chumphorn","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-31","2026-09-27",true,{"@type":102,"interactionType":103,"userInteractionCount":34},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What is the purpose of biochemical tests in bacterial identification?","Question",{"text":112,"@type":113},"Biochemical reactions are important for identifying bacterial isolates and differentiating bacterial species. They rely on enzyme presence and activity produced by bacteria.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How do you interpret a positive catalase test?",{"text":117,"@type":113},"Mixing H2O2 with the tested bacteria produces gas bubbles of O2 for a positive catalase test. No bubbles indicate a negative result.",{"name":119,"@type":110,"acceptedAnswer":120},"What determines whether gelatin is liquefied in the gelatinase test?",{"text":121,"@type":113},"After incubation and refrigeration, hydrolyzed gelatin remains liquid, while non-hydrolyzed gelatin re-solidifies. This difference is used to record the results.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},398684,1790805443,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":19,"category_name":20,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":34,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":41,"preview_page_count":4},2336475401981,"https://ap-avatar.wpscdn.com/avatar/22000c94efd8d5204d?x-image-process=image/resize,m_fixed,w_180,h_180&k=1786935347598174694","Lab 10 (Biochemical Tests)  \nBiochemical Tests:  \n• Biochemical reactions are very important in the identification of bacterial isolates and in the identification of different bacterial species.  \n• These tests depend on the presence of certain enzymes, such as catalase, oxidase, urease, gelatinase, etc., produced by the bacteria.  \n• Different bacteria produce varying spectra of enzymes. For example, some enzymes are necessary for the bacterium’s individual metabolism, and some facilitate the bacterium’s ability to compete with other bacteria or establish an infection.  \n• Tests that measure single bacterial enzymes are simple, rapid, and generally easy to interpret.  \n• They can be performed on organisms already grown in culture and often provide presumptive identification.  \nCatalase Test:  \n• Some bacteria contain flavoproteins that reduce O2 resulting in the production of hydrogen peroxide (H2O2) or superoxide (O2) . These are toxic for obligate aerobes and facultative anaerobes.  \n• Many bacteria produce enzymes to protect them self against superoxide (O2), these enzymes are catalase, peroxidase or superoxide dismutase , which catalyze the destruction of H2O2 or O2 as follows :  \n• Catalase production can be noted by mixing H2O2 with the tested bacteria. Bubbles of O2 represent a positive catalase test, and the absence of bubbles represent a negative catalase test.  \n• Most strict anaerobes lack both enzymes and cannot tolerate O2  \nProcedure  \n1. Label two nutrient broths or nutrient agar slants.  \n2. Using aseptic technique, inoculate one agar slant or broth with staphylococcus and the other tube with streptococcus.  \n3. Incubate all the cultures at 37ºC for 18 to 24 hours.  \n4. Add few drops of 3% H2O2 over the growth of the slants or broths and observe the appearance of gas bubbles.  \n5. Record the results.  \nOxidase Test:  \n• Oxidase enzymes have an important role in the electron transport system during aerobic respiration.  \n• This test is used to identify bacteria that produce cytochrome c oxidase, an enzyme of the bacterial electron transport chain.  \n• All bacteria that are oxidase positive are aerobic, and can use oxygen as a terminal electron acceptor in respiration.  \n• This test is used in the differentiation between the oxidase positive bacteria (Neisseria, Pseudomonas and Vibrio) and the other gram-negative bacteria.  \n• The oxidase reagent that used is tetramethyl-p-phenylenediamine dihydrochloride (TMPD) .  \n• The test principle is simplified as follows:  \nProcedure method:  \n1. Divide the agar plate in two parts by wax pencil.  \n2. Using a septic technique, streak one part with Neisseria or Pseudomonas, and streak the other part with E. coli.  \n3. Incubate the plate in an inverted position for 18 to 24 hours at 37ºC.  \n4. Add 2 to 3 drops ofthe oxidase reagent to the surface of the growth, on each part.  \n5. Observe the presence (oxidase +) or absence (oxidase-) of color change of colony from pink to purple and finally to dark purple. Color change will occur within 20 to 30 seconds.  \n6. Record the results.  \nSecond method  \n1. Transfer bacterial growth to filter paper.  \n2. Add few drops of oxidase reagent on the bacterial growth.  \n3. Observe the color change after 20 to 30 seconds.  \nCoagulase Activity Test:  \n• The coagulase test is used to differentiate strains of Staphylococcus aureus from S. epidermidis and other coagulase-negative species.  \n• Coagulase is enzyme produced by pathogenic Staphylococci that clot blood plasma.  \n• Citrate is usually added to act as anticoagulant and prevent false positive results, however; S. aureus strains are usually capable of coagulating EDTA-treated plasma in the tube test andwill produce clumps of cells in the slide test.  \nProcedure  \n1. Add 0.5 ml of citrated rabbit plasma to two small test tubes, label the tubes with name of bacteria.  \n2. Add 0.5 ml broth culture ofS. aureus to one tube and 0.5 ml broth culture ofS. epidermis to the other tube.  \n3. Incuba","cbCairFVDL5pance","https://ap.wps.com/l/cbCairFVDL5pance","pdf",1347498,12,"English","# Biochemical Tests (Lab 10)\n## Catalase Test\n## Oxidase Test\n## Coagulase Activity Test\n## Urease Test\n## Gelatinase Hydrolysis (Gelatin Liquefaction) Test","[{\"question\":\"What is the purpose of biochemical tests in bacterial identification?\",\"answer\":\"Biochemical reactions are important for identifying bacterial isolates and differentiating bacterial species. They rely on enzyme presence and activity produced by bacteria.\"},{\"question\":\"How do you interpret a positive catalase test?\",\"answer\":\"Mixing H2O2 with the tested bacteria produces gas bubbles of O2 for a positive catalase test. No bubbles indicate a negative result.\"},{\"question\":\"What determines whether gelatin is liquefied in the gelatinase test?\",\"answer\":\"After incubation and refrigeration, hydrolyzed gelatin remains liquid, while non-hydrolyzed gelatin re-solidifies. This difference is used to record the results.\"}]","Lab 10 (Biochemical Tests) - Procedure | PDF",1790488052]