Showing papers on "Agar plate published in 2008"
TL;DR: The aim of broth and agar dilution methods is to determine the lowest concentration of the assayed antimicrobial agent (minimal inhibitory concentration, MIC) that, under defined test conditions, inhibits the visible growth of the bacterium being investigated.
Abstract: The aim of broth and agar dilution methods is to determine the lowest concentration of the assayed antimicrobial agent (minimal inhibitory concentration, MIC) that, under defined test conditions, inhibits the visible growth of the bacterium being investigated. MIC values are used to determine susceptibilities of bacteria to drugs and also to evaluate the activity of new antimicrobial agents. Agar dilution involves the incorporation of different concentrations of the antimicrobial substance into a nutrient agar medium followed by the application of a standardized number of cells to the surface of the agar plate. For broth dilution, often determined in 96-well microtiter plate format, bacteria are inoculated into a liquid growth medium in the presence of different concentrations of an antimicrobial agent. Growth is assessed after incubation for a defined period of time (16-20 h) and the MIC value is read. This protocol applies only to aerobic bacteria and can be completed in 3 d.
4,223 citations
TL;DR: This is the first report on the use of Gram’s iodine for the detection of cellulase production by microorganisms using plate assay, which is rapid and efficient and can be easily performed for screening large numbers of microbial cultures of both bacteria and fungi.
Abstract: Screening for cellulase-producing microorganisms is routinely done on carboxymethylcellulose (CMC) plates. The culture plates are flooded either with 1% hexadecyltrimethyl ammonium bromide or with 0.1% Congo red followed by 1 M NaCl. In both cases, it takes a minimum of 30 to 40 minutes to obtain the zone of hydrolysis after flooding, and the hydrolyzed area is not sharply discernible. An improved method is reported herein for the detection of extracellular cellulase production by microorganisms by way of plate assay. In this method, CMC plates were flooded with Gram’s iodine instead of the reagents just mentioned. Gram’s iodine formed a bluish-black complex with cellulose but not with hydrolyzed cellulose, giving a sharp and distinct zone around the cellulase-producing microbial colonies within 3 to 5 minutes. The new method is rapid and efficient; therefore, it can be easily performed for screening large numbers of microbial cultures of both bacteria and fungi. This is the first report on the use of Gram’s iodine for the detection of cellulase production by microorganisms using plate assay.
689 citations
TL;DR: The traditional use of this plant is justified for the treatment of stomach discomfort, diarrhea, dysentery and as a remedy for wound healing whose causative agents are some of the organisms used in this study.
Abstract: The methanolic leaf extract of Newbouldia laevis was subjected to preliminary phytochemical screening and in-vitro antimicrobial tests. The extract revealed the presence of flavonoids, tannins, terpenes, steroidal and cardiac glycosides. The antimicrobial activity of the plant extract was assayed by the agar plate disc diffusion and nutrient broth dilution techniques. Test microorganisms were Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Klebsiella spp. and Candida albicans; all the organisms were laboratory isolates. The extract inhibited the growth of all the test organisms especially against Klebsiella spp. and S. aureus which had mean inhibition zone of 42.3±1.5 and 32.3±1.5 mm respectively. The results showed minimum inhibitory concentration (MIC) of 1.563 mg/ml against Escherichia coli and Klebsiella spp. and 3.125 mg/ml against Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhi. The minimal bactericidal concentration (MBC) against Escherichia coli and Staphylococcus aureus was 0.39 mg/ml. This study has justified the traditional use of this plant for the treatment of stomach discomfort, diarrhea, dysentery and as a remedy for wound healing whose causative agents are some of the organisms used in this study.
130 citations
TL;DR: Lactic acid bacteria were isolated from four different sourdough bread cultures previously investigated for antifungal activity and the most inhibitory isolate obtained was identified by API 50 CHL and 16s ribosomal RNA genotyping and found to be Lactobacillus paracasei ssp.
122 citations
TL;DR: The result showed that the A3-15 amylase enzyme was both, highly thermostable-alkaline, thermophile and chelator resistant and may be suitable in liquefaction of starch in high temperature, in detergent and textile industries and in other industrial applications.
119 citations
TL;DR: The antibacterial effect of suspended miswak pieces suggests the presence of volatile active antibacterial compounds in the region of periodontitis and caries.
Abstract: BACKGROUND: The chewing stick (miswak) is used for oral hygiene in many parts of the world. In addition to the mechanical removal of plaque, an antibacterial effect has been postulated; however, tests of miswak extract from Salvadora persica (Arak) disclosed only low to moderate antibacterial effects. This may be attributable to the extraction process. Our aim was to test in vitro the antibacterial effect of miswak pieces, without extraction, on bacteria implicated in the etiology of periodontitis and caries. METHODS: Miswak pieces were standardized by size and weight (0.07 and 0.14 g) and tested against Streptococcus mutans, Lactobacillus acidophilus, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and, as a reference, Haemophilus influenzae. The miswak pieces were tested in two ways: embedded in the agar plate or suspended above the agar plate. RESULTS: The inhibitory effect was most pronounced on P. gingivalis, A. actinomycetemcomitans, and H. influenzae, less on S. mutans, and least on L. acidophilus. Suspended miswak had comparable or stronger effects than miswak embedded in agar. The 0.14-g suspended miswak exhibited significantly greater inhibition on A. actinomycetemcomitans and H. influenzae than the 0.14-g miswak embedded in agar (P<0.01 and P<0.001, respectively). CONCLUSIONS: Miswak embedded in agar or suspended above the agar plate had strong antibacterial effects against all bacteria tested. The antibacterial effect of suspended miswak pieces suggests the presence of volatile active antibacterial compounds.
112 citations
Journal Article•
TL;DR: The results show that rhizospheric phosphate utilizing bacteria could be a promising source for plant growth promoting agent in agriculture.
Abstract: Rhizospheric bacteria are known to influence plant growth by direct and indirect mechanisms. A total of 220 phosphate solubilizing bacteria were isolated from different rhizosphere soil in Northern part of Thailand. These isolates were screened for their plant growth promoting factors like production of ammonia, siderophore and cell wall degrading enzyme activities; cellulase, chitinase and proteolytic enzyme. More than 64% of the isolates produced ammonia and 23% produced siderophore on chrome azurole S agar plates. Moreover, test isolates produced cell wall degrading enzyme; cellulose (6%), chitinase (6%) and proteolytic enzyme (5%) on agar plate method. The results show that rhizospheric phosphate utilizing bacteria could be a promising source for plant growth promoting agent in agriculture.
107 citations
TL;DR: Both cellulolytic Streptomyces isolates gave almost equal quantity of enzyme in all trials, however the effect of medium ingredients on endoglucanase induction diverged with strains in some extent.
101 citations
TL;DR: The chromogenic agar medium chromID ESBL (bioMerieux) was compared with BLSE agar Medium (AES) for selective isolation and presumptive identification of extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae from clinical samples as mentioned in this paper.
Abstract: The chromogenic agar medium chromID ESBL (bioMerieux) was compared with BLSE agar medium (AES) for selective isolation and presumptive identification of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae from clinical samples. A total of 765 samples (468 rectal swabs, 255 urine samples and 42 pulmonary aspirations) obtained from 547 patients was processed. All bacterial strains isolated on either medium were further characterized using biochemical tests, and ESBL producers were confirmed by synergy testing. Genetic characterization of ESBL genes was determined by PCR. A total of 33 ESBL-producing Enterobacteriaceae strains [Escherichia coli (n=16), Klebsiella pneumoniae (n=8), Enterobacter spp. (n=3), Citrobacter spp. (n=5) and Proteus mirabilis (n=1)] was recovered. The sensitivity after 24 h incubation was 88 % for chromID ESBL and 85 % for BLSE agar. At 48 h, the sensitivity of chromID ESBL increased to 94 % and was higher than that obtained with BLSE agar. The positive predictive value at 24 h for chromID ESBL was 38.7 % [95 % confidence interval (95 % CI) 28.3 -50.2 %)], which was significantly higher than that for BLSE agar [15.4 %, 95 % CI 10.1 -21.5 %]. On both media, false-positive results were mostly due to Pseudomonas aeruginosa and to Enterobacteriaceae overproducing chromosomal cephalosporinase (Enterobacter spp.) or a chromosomal penicillinase (Klebsiella oxytoca). This study showed that chromID ESBL, a ready-to-use chromogenic selective medium, is sensitive and specific for rapid, presumptive identification of ESBL-producing Enterobacteriaceae. Its chromogenic properties and its selectivity are particularly useful in specimens containing resident associated flora.
87 citations
TL;DR: The draft of the horizontal method for the detection of Salmonella species from human food and animal feed was compared to the European gold standard and no significant difference was obtained by comparing the ISO 6579:2002 draft to the gold standard.
84 citations
TL;DR: Based on the pathogenicity, isolates of A. solani were rated as virulent or less virulent based on percentage disease incidence data, and most efficient amplification and polymorphism of DNA was found with random primer 5′-CGCGTTCCTG-3′.
Abstract: Early blight (Alternaria solani) is an important disease causing severe damage in tomato. The eleven isolates of A. solani designated as So, Dh, Sh, Va-5, Ka, Ma, Hy, Ba-1, My, Va-3 and Mi were collected from different agroclimatic conditions and these isolates were characterized for cultural, morphological, pathogenic and molecular variations. The pigmentation varied from yellow, brown, black, brownish to greenish black in isolates of A. solani on potato dextrose agar medium. In general, radial growth of all isolates ranged between 14.9 mm and 32.2 mm on PDA and 24.3 mm to 53.7 mm on three selective media i.e., ASM, V-8 juice agar and V-8 juice agar (synthetic) on the fourth day. The fastest radial growth was recorded in the So isolate and slowest in the Ka isolate on PDA, while isolates Dh, Ba-1 and Va-3 were recorded to be faster in growth on ASM, V-8 juice agar and V-8 juice agar (synthetic) medium. The thickness of conidiogenous hyphae varied between 1.17 μ and 9.56 μ, with maximum in the Va-5 and Ma isolates. Most of the isolates showed smooth mycelial growth with circular and irregular margin and without concentric zonation. Sporulation was not found in any of the isolates on four different nutrient media, whereas conidiogenous hyphal length was observed in V-8 juice agar medium only. Based on the pathogenicity, isolates of A. solani were rated as virulent or less virulent based on percentage disease incidence data. Molecular variability studies were also done to find out the best annealing temperature and eighty-six primers were screened to select for maximum polymorphism of DNA. The best annealing temperature was recorded between 32.5 °C and 34.0 °C for the pathogen, and most efficient amplification and polymorphism of DNA was found with random primer 5′-CGCGTTCCTG-3′.
TL;DR: Effects of volatile organic compounds produced during interspecific mycelial interactions were examined by measuring extension rate of ‘target’ fungi growing in agar plates taped above two interacting mycelia – Bjerkandera adusta, Hypholoma fasciculare, Stereum gausapatum and Trametes versicolor in all combinations.
TL;DR: A gradual decline in resistance to infection among patients in the age group 51 and above could be responsible for the high prevalence rate observed in this study.
Abstract: The aim of the study was to isolate aerobic bacteria and Candida albicans from post-operative wounds, establish the antimicrobial susceptibility pattern of isolated bacterial agents and proffer ways and means for the prevention of post-operative wound infections. A total of 350 swab specimens from post-operative wounds of consenting patients in Central Hospital, Benin City, were screened for the presence of aerobic pathogens and C. albicans using standard bacteriological methods. The samples were collected using sterile Evepon swab sticks and inoculated onto Blood Agar, MacConkey Agar and Sabouraud Dextrose Agar plates. The 348 specimens (96.4%) yielded pathogens in the following order:Staphylococcus aureus (35.0%), Pseudomonas aeruginosa (26.0%), Escherichia coli (13.0%), C. albicans (9.3%), Klebsiella aerogenes (7.4%), Proteus spp. (7.4%) and Streptococcus spp. (1.9%). The highest infection was seen in the age group 51 years and above, followed by 41 - 50, 21 - 30 and 11 - 20, while 0 - 10 years gave the lowest incidence. A gradual decline in resistance to infection among patients in the age group 51 and above could be responsible for the high prevalence rate (100%) observed in this study. The anti-microbial susceptibility test indicated that there were differences in the sensitivity and resistance patterns of the isolates.
Key words: Aerobes, Candida albicans, post-operative wounds, infections.
TL;DR: The objective of this study was to evaluate the effects of naringin on the growth of periodontal pathogens such as A. actinomycetemcomitans and P. gingivalis in vitro.
Abstract: Naringin is a flavonoid that is commonly found in grapefruits. The objective of this study was to evaluate the effects of naringin on the growth of periodontal pathogens such as A. actinomycetemcomitans and P. gingivalis in vitro. For comparison, the effects of naringin on several oral microbes were also studied. Different concentrations of naringin solution were added to calibrated suspensions of A. actinomycetemcomitans and P. gingivalis. All the suspensions were incubated for 3, 6 and 24 h in an anaerobic chamber at 37 degrees C. At each time point, selected dilutions from each culture broth were plated on blood agar plates. Colonies recovered on blood agar were visually counted on days 3 and 5, respectively. A. actinomycetemcomitans showed a significant decrease (p < 0.05) in viable counts after 3 h when naringin was added at baseline. P. gingivalis also showed a marked growth reduction in the presence of naringin, and no colony forming units could be observed after 24 h. Naringin also had an inhibitory effect against all bacteria and yeasts tested. The results suggest that naringin possesses significant antimicrobial properties on periodontal pathogens in vitro. It also has an inhibitory effect on some common oral microorganisms in low concentrations.
TL;DR: Hewitt et al. as discussed by the authors determined the optimal conditions of media required to selectively detect marine bacteria and applied the technique to drowned cadavers and found that the results indicated that the presence of marine bacteria could be a marker of drowning in seawater.
TL;DR: This study proposes the use of an agar medium that contains cellobiose as the fermentable sugar, a chromogenic substrate and selective inhibitors for suppression of colony formation by many competing bacteria, YeCM, for isolation of potentially virulent Y. enterocolitica.
TL;DR: The use of lidocaine gel before application of povidone–iodine 5% resulted in decreased effectiveness of antisepsis and increased microbial survivability, which may increase the risk for postoperative infection in ocular surgery performed under topical anesthesia.
Abstract: PURPOSE: To determine whether the use of lidocaine gel prior to povidone-iodine antisepsis is associated with increased microbial survival. SETTING: Ophthalmology Department, Madigan Army Medical Center, Fort Lewis, Washington, USA. METHODS: A standardized suspension of Staphylococcus epidermidis was used to inoculate 5 blood agar plates that served as a control. A second group of 5 blood agar plates was inoculated, and then lidocaine gel was applied to the plates. A third group of 5 blood agar plates was inoculated, lidocaine gel was applied, and then povidone-iodine 5% was applied and allowed to cover the plates. A fourth group of 5 blood agar plates was inoculated, and then povidone-iodine 5% was allowed to cover the plates. Cultures of Staphylococcus aureus, Pseudomonas aeruginosa, and Haemophilus influenza were tested in a similar fashion. Microbial growth was evaluated after 24 hours. RESULTS: The number of colony forming units (CFUs) was similar in the control group and the S epidermidis, S aureus, and P aeruginosa lidocaine only and lidocaine with povidone-iodine groups. In these groups, each plate grew between 200 CFUs and 300 CFUs. In the Haemophilus influenza series, the lidocaine with povidone-iodine group had fewer CFUs than the control group. In all 4 series, the povidone-iodine only group had the least amount of CFUs, ranging from 0 to 6. CONCLUSIONS: The use of lidocaine gel before application of povidone-iodine 5% resulted in decreased effectiveness of antisepsis and increased microbial survivability. The increase in microbial survivability may increase the risk for postoperative infection in ocular surgery performed under topical anesthesia.
TL;DR: Wholesale cuts of fresh beef were vacuum packaged at low, intermediate or high degrees of vacuum and stored at l-3°C for 7, 14, 21, 28 or 35 days, with largest increases in bacterial counts occurred between 14 and 21 days of storage.
Abstract: Wholesale cuts of fresh beef were vacuum packaged at low, intermediate or high degrees of vacuum and stored at l-3°C for 7, 14, 21, 28 or 35 days. Bacterial counts of samples after 7 and 14 days of storage were low [mean count < 104 per in.2 (6.45 cm2)] irrespective of degree of vacuum. Lactobacilli and anaerobic agar plate counts of cuts stored under high vacuum for 21-35 days tended to be lower than those of comparable cuts stored under low or intermediate vacuum. This was also true, but much less frequently, for the psychrotrophic and mesophilic counts. Largest increases in bacterial counts occurred between 14 and 21 days of storage. Fluorescent pseudomonads represented only a small percentage of the total microbial population of vacuum packaged beef cuts. Lactobacilli and anaerobic plate counts of vacuum-packaged cuts were very similar. The psychrotrophic bacterial population of cuts stored for 28 days consisted primarily of Lactobacillus sp., while Pseudomonas sp. and Enterobacteriaceae represented only a small percentage of the psychrotrophic microflora at that time.
TL;DR: Polymixin B, gentamicin or ciprofloxacin topical preparations should be used as first line treatment of otitis externa and resistance to penicillin and amoxicillin is observed.
TL;DR: Larger zones of inhibition were consistently observed for higher concentrations of calcium hydroxide with statistical significance among the bacteria, particularly between 40% and 60%.
TL;DR: Two types of selective media were tested and compared to blood agar plates for screening of Group B streptococcus vaginal colonization in pregnant women and all tested media were comparable in terms of sensitivity; their use in routine laboratories may markedly facilitate the rapid detection of GBS in vaginal samples.
Journal Article•
TL;DR: The antibacterial resistant pattern of aerobic bacteria, isolate from burn patients admitted in plastic surgery & general surgery wards of Chhatrapati Shahuji Maharaj Medical Uni-versity, Lucknow were studied and pesu-domonas which was the commonest isolate was most resistant to Ceftazidime followed by Cefotaxime.
Abstract: The antibacterial resistant pattern of aerobic bacteria, isolate from burn patients admitted in plastic surgery & general surgery wards of Chhatrapati Shahuji Maharaj Medical Uni-versity, Lucknow (a tertiary care hospital) were studied. 100 patients were enrolled from plastic surgery & general surgery wards and 200 samples were collected which comprised of 100 burn wound swabs & 100 biopsies of same patients. All samples were cultured on Nutrient agar, Mac conkey agar and Blood agar at 37oc for 24 hrs. The isolates were identified by culture, staining and biochemical tests including oxidase, lactose and maltose fermentation, catalase and their antibiotic sensitivity determined using Kirby Bauer disc diffusion technique. The most common isolate was Pseudomonas aeruginosa-55.0%, followed by Staphylococcus aureus-19.29%, Klebsiella spp.-11.43%, Acinetobacter spps-7.14%. Proteus spp 4.29%, Es-cherichia coli-2.85%. Resistance of S.aureus was 40% observed with Oxacillin & 84% to Erythromycin whereas all strains were susceptible to Vancomycin. We analyzed that pesu-domonas which was the commonest isolate was most resistant to Ceftazidime (70%) followed by Cefotaxime. Ciprofloxacin (55.5%) & Amikacin (54.0%) were found to be most effective antimicrobial agent (7, 11). Other Gram-negative organisms were highly resistant to Cefo-taxime (66.0%) followed by Gentamycin (60.0%).). Imipenem was found to be less resistant (26%) against Pseudomonas.
TL;DR: Screening medicinal plants widely used in Thailand as possible sources of medicines that can be used to treat H. pylori infection found that P. granatum and Q. infectoria exhibited the greatest inhibitory potencies.
Abstract: Multiple antibiotic-resistant Helicobacter pylori (H. pylori), one of the major causes of gastric cancer, is now increasingly reported. The aim of this study was to screen medicinal plants widely used in Thailand as possible sources of medicines that can be used to treat H. pylori infection. Twenty-four extracts from 13 kinds of Thai herbs were tested for their antibacterial activity against 20 strains of antibioticresistant H. pylori .I nhibition of growth was tested by the paper disc agar diffusion method. Most strains of H. pylori examined were proved to be susceptible to seven medicinal plants; i.e., Peltophorum pterocarpum, Piper betle, Punica granatum (P. granatum), Quercus infectoria (Q. infectoria), Tamarindus indica, Uncaria gambir ,a ndWalsura robusta. Among these extracts, P. granatumand Q. infectoriaexhibited the greatest inhibitory potencies. Minimal inhibitory concentrations (MIC) were determined by the agar dilution method in Petri dishes with a Millipore filter membrane, and minimal bactericidal concentrations (MBC) were assessed with the extract that gave as ignificant MIC value against each bacterial strain by placing the Millipore filter membrane onto a fresh Isosensitest agar plate. Ethanolic extracts of P. granatum andQ. infectoriasignificantly reduced the growth of all strains of H. pylori ,w ith thebest MIC values at 0.8 and 3.1mg/ml, and the best MBC values at 3.1 and 6.2mg/ml, respectively. Effective fractions par
TL;DR: UPA, CMDA, BCP-MS-G, LJA, and BHIA may be used as common mycological agars in routine practice and a special algorithm containing the various test procedures employed in these studies is presented which was found to be useful in the differentiation of T. rubrum strains from T. mentagrophytes complex.
Abstract: The two most frequently encountered dermatophyte etiologic agents of glabrous skin and nail dermatophytoses are Trichophyton rubrum and T. mentagrophytes. This study was aimed to discuss the efficacy of morphological, physiological and biochemical diagnostic tests commonly used in the identification of T. rubrum and members of the T. mentagrophytes complex. In this study, we evaluated; hydrolysis of urea in broth and on urea agar slants and Petri plates incubated at 22 degrees C, 28 degrees C and 37 degrees C, in vitro hair perforation (blond child, sheep and goat hair), pigment production on cornmeal dextrose agar (CMDA) and bromcresol purple-milk solids-glucose agar (BCP-MS-G), Tween opacity, sorbitol assimilation, and salt tolerance. Additionally, the production of micro- and macroconidia was investigated by using brain heart infusion agar (BHIA), Christensen's urea agar in Petri plates (UPA), CMDA, Lowenstein-Jensen agar (LJA), malt extract agar, oatmeal agar, Oxoid chromogenic Candida agar, and potato dextrose agar. All cultures were incubated at 28 degrees C, and conidial production was compared on days 5, 10 and 15. It was found that the urea hydrolysis test yielded more rapid and significant results when urea medium was prepared in Petri plates and incubated at 28 degrees C (P<0.01). LJA supported the highest production of microconidia after 15 days (P<0.001). Additionally, it was found that T. rubrum strains produced red pigment on CMDA (P<0.01) and BCP-MS-G, while strains of the T. mentagrophytes species complex did not. A special algorithm containing the various test procedures employed in these studies is presented which was found to be useful in the differentiation of T. rubrum strains from T. mentagrophytes complex. Our results revealed that UPA, CMDA, BCP-MS-G, LJA, and BHIA may be used as common mycological agars in routine practice.
01 Jan 2008
TL;DR: This study surveyed bacteria disease infected in freshwater imported ornamental fish in Kuala Terengganu, Malaysia and determined bacteria of the present study were opportunistic and temperature, which are common problem for the suspected single and pure bacterial colony.
Abstract: instance, the study of Dixon and Contreras [1] showed the A survey of bacteria disease infected in freshwater imported ornamental fish. Furthermore, the imported ornamental fish in retail pet shop in Kuala Terengganu, gourami from Asia was found infected by Yersinia Terenggganu, Malaysia was conducted from July to ruckeri, a causative agent of enteric red mouth September, 2007. The collected diseased fish were disease. Therefore, this study was conducted to Dwarf Gourami (Colisa lalia), Discus (Symphysodon survey bacterial disease infected in ornamental fish aequifasciatus), Discus Cichlids (Symphysodon spp.), in Kuala Terengganu, Malaysia and antibiogram of Black Tetra (Gymnocorymbus ternetzi), Swordtail isolated bacteria. Approximately fifty diseased freshwater (Xiphophorus helleri), Platy (Xiphophorus maculates), ornamental fish were collected from an aquarium shop in Variegated platy (Xiphophorus variatus), Black Ruby Kuala Terengganu, Terengganu, Malaysia. They were Barb (Barbus nigrofasciatus), Tiger Barb (Barbus brought back to laboratory using plastic bag filled with pentazona hexazona), Sumatra Barb (Barbus tetrazona), provided aquarium water from pet aquarium shop. Fighting Fish (Betta splendens), Guppy (Poecilia Externally, cotton bud was used to swab onto the lesion reticulata), Mollies (Poecillia spp.) and Silver Catfish while internally intraperitoneal fluid of the diseased fish (Pangasuis sutchi). The bacteria were isolated using was swabbed aseptically and spread on blood agar plate, blood agar plate, cytophaga agar plate, GSP agar plate, cytophaga agar plate, glutamate starch phenol red (GSP) XLD agar plate and MacConkey agar without crystal agar (Merck, Germany) plate, Xylose Lysine Deoxycholate violet plate. The isolated bacteria were identified using (XLD) agar (Merck, Germany) plate and MacConkey agar commercial identification kit. Antibiogram of the isolated without crystal violet (Difco, USA) plate, separately. After bacteria of the present study were also determined. incubation for 24 h, the inoculated plates were examined Nowadays, bacterial disease is a common problem for the suspected single and pure bacterial colony. The faced by ornamental fish industry. Bacterial Gram bacteria were then kept in Trypticase Soy Agar (TSA) negative is recognized as causative agent of many (Merck, Germany) deep tube for identification purpose. bacterial diseases attacking ornamental fish. The identification of the suspected bacteria was done Aeromonas, Citrobacter, Flavobacterium, Edwardsiella, using commercial identification kit (BBL Crystal, USA). Mycobacterium, Pseudomonas and Vibrio are Gram The identified bacterial were cultured in Trypticase negative bacteria usually isolated from the diseased Soy Broth (TSB) (Merck, Germany) for 24 h at room ornamental fish. These bacteria were opportunistic and temperature. The bacterial suspensions were adjusted ubiquitous in the aquatic environment. Many factors into 10 CFU/ml and spread on Mueller Hinton agar could contribute to bacterial infection in ornamental fish (Oxoid, England). Antibiotic disks were then placed on the namely poor water quality, crowding, transportation and MH agar plate and incubated for 24 h at room temperature. inadequate nutrition. Many cases of bacterial infections The diameter of inhibition zones of the each tested in ornamental fish have been reported worldwide. For antibiotic disk was measured and interpreted as sensitive presence of multi drug resistant Edwardsiella tarda in the
TL;DR: In the present study three mesophilic Bacillus isolates were analyzed for their α-amylase activity in shakeflask cultures and it was found that B. subtilis was the best producer of the enzyme, which was followed by the newly isolated Bacillus sp.
Abstract: In the present study three mesophilic Bacillus isolates were analyzed for their α-amylase activity in shakeflask cultures. The organisms were capable to produce hydrolysis zone around their colonies on starch agar medium. The effect of various fermentation conditions on α-amylase production was investigated, and in every case it was found that B. subtilis was the best producer of the enzyme, which was followed by the newly isolated Bacillus sp. and B. amyloliquefaciens. The synthesis of extracellular α-amylase by the bacteria was repressed by the presence of readily metabolizable carbon source like glucose in the culture medium. Maximum α-amylase activity by the Bacillus isolates was obtained at 37°C with an initial medium pH 7.0 under agitation at 160-180 rpm for 72 h of growth. Keywords: Bacillus species, α-Amylase, Enzyme production, Shake-flask cultureDOI: http://dx.doi.org/10.3329/bjm.v24i2.1257 Bangladesh J Microbiol, Volume 24, Number 2, December 2007, pp 129-132
TL;DR: The recovery of hydrogen peroxide-producing lactobacilli decreases with the increasing pregnant age and time.
TL;DR: A preliminary assessment of a new instrument designed for the inoculation and spreading of specimens for microbiological analysis onto agar plates found that the instrument was able to select full or biplates from a number of input cassettes, each containing different agar types.
Abstract: The findings from a preliminary assessment of a new instrument designed for the inoculation and spreading of specimens for microbiological analysis onto agar plates are described. The study found that the instrument was able to select full or biplates from a number of input cassettes, each containing different agar types. Samples were then inoculated by the instrument onto the agar surfaces and spread by a novel plastic applicator. Following this, the instrument labeled the plates and sorted them into a number of specified output stations. It was found that the instrument was able to inoculate and spread samples over a greater proportion of the agar plate surface than the manual loop-to-plate method. As a consequence, up to 44% more usable colonies were produced per plate from clinical specimens and standard cultures. Viable counts showed that the instrument was able to detect as few as 10 2 CFU/ml in fluids and also facilitated the enumeration of organisms, particularly in specimens such as urine.
TL;DR: Surface motility of the polycyclic aromatic hydrocarbon (PAH)-degrading Mycobacterium gilvum VM552 was tested on agar and agarose plates prepared with varying amounts of gelling agents in the presence and absence of phenanthrene and it was suggested that formation of branches was the combined effect of cell division and growth at the tip of a branch and propulsion of cells from the mature basal parts of a Branch towards the tip.
TL;DR: The purpose of this study was to determine the effectiveness of several different procedures in detecting β‐d‐glucuronidase activity and hence in detecting E. coli.
Abstract: Aims: Testing for b-d-glucuronidase activity has become the basis of many methods for the detection of Escherichia coli in both food and water. Used in combination with tests for the presence of b-d-glucuronidase, these tests offer a simple method for simultaneously detecting coliforms and E. coli. The purpose of this study was to determine the effectiveness of several different procedures in detecting b-d-glucuronidase activity and hence in detecting E. coli. Methods and Results: The ability of membrane lactose glucuronide agar