Micrococcus Varians Research Articles

Bacteriological Assessment of Ready-To-Eat Foods Sold in Baze University Student Cafeteria

Although foods can be easily contaminated by naturally occurring microbes or pathogens by any means possible, safe eating is considered as a basic human right. In this study, the bacteriological quality of ready-to-eat (RTE) foods sold within the Baze University campus were assessed. Ready-to-eat food samples including spaghetti, fried rice, jollof rice, yam and moi-moi were bought from different major food vending sites to the student and staff community within the university. The Bacterial species were isolated from food samples and the isolates were identified using standard microbiological procedures. The ability of the isolates to produce hemolysins and lyse blood cells was investigated with hemolysis test and the antibiotic susceptibility pattern of the isolates was determined with the following antibiotics: Amoxicillin, Ampicillin, Tetracycline, Ciprofloxacin, Erythromycin and Gentamicin. The sensitivity and resistance of the isolates to these antibiotics were observed and recorded. A total of six (6) different bacterial species including Corynebacterium spp. (31.6%), Staphylococcus spp. (26.3%), Streptococcus (10.5%), Micrococcus spp. (10.5%), Lactobacillus spp. (15.8) and Micrococcus varians (5.3%) were isolated and identified. The isolates also showed varying reactions to hemolysis and some were highly resistant to common antibiotics, signaling their tendency to initiate foodborne illness. The study concluded that while these sites are necessary in meeting the needs of the university community, it is important that adequate safety measures be enforced to reduce the spread of pathogenic bacterial contaminants in RTE foods and enhance the wellbeing of consumers.

Identifikasi Keragaman Mikroflora dan Pengaruhnya pada Kualitas Organoleptik Tempoyak Khas Suku Dayak di Kalimantan Tengah

Tempoyak as local wisdom and national culture is poorly documented. Therefore, it is important to explore the preferences of the millennial generation regarding the organoleptic qualities of Tempoyak. The research design is a one-shot case study. The variables tested were the diversity of microflora in tempoyak, and its influence on the level of organoleptic quality and the level of preference of the millennial generation. Identification of isolates using API-50CHL, biochemical tests and physiological tests. Organoleptic quality uses the hedonic scale test. The research panelists were 120 people from the Dayak, Madura, Jawa and Banjar tribes. Data analysis uses one way Anava analysis. 15 isolates of microflora were found in Tempoyak which affected its taste and organoleptics, 8 isolates including lactic acid bacteria, including Pediococcus acidilactici, Lactobacillus curvatus, Leuconostoc mesenteroides, Lactobacillus plantarum, Streptococcus thermophiles, Lactobacillus pentosus, Enterococcus faecium, and Weissella paramesenteroides. 1 isolate of non-lactic acid bacteria that is Micrococcus varians. 2 isolates from the yeast group consisted of Saccharomyces cereviciae and Kluyveromyces marxianus, and 4 isolates included Rhizopus, Monilia sitophila, and Mucor roxii. All microflora found were capable of producing lactic acid, except Aspergillus repens. The statistical test results show the significance of its influence on the organoleptic quality of all sub-variables, including color, taste, aroma and texture of Tempoyak. The exploration results in this research indicate opportunities for Tempoyak to be more developed, innovative and contemporary, so that it is preferred by the millennial generation.

Phenotypic and Genetic Characterization of Polyhydroxyalkanoate Producing Bacterial Isolates from Hypersaline Water Body, Atlantic Ocean, Nigeria

Introduction: The importance of polyhydroxylalkanoate (PHA) producing bacteria is hinged on the basis that PHA itself possess environmentally advantages over synthetic plastics therefore, the proper identity of these bacteria is inevitable.
 Aim: To determine the bacteria identification methods of phenotypic and genetic identification for marine sourced effective polyhydroxylalkanoate (PHA) production.
 Study Design: Randomised design was employed for PHA producing bacterial isolates.
 Place and Duration of Study: Samples containing PHA-producing bacteria from the hypersaline water body of Nigerian Southern Atlantic Ocean (6.35ᴼ N 3.28ᴼ E -St1; 6.35ᴼ N 3.40ᴼ E -St2; and 6.36ᴼ N 3.47ᴼ E -St3); water depths (0.07m (top), 50m (middle) and 100m (bottom) were collected and investigated between August, 2016-September, 2019.
 Methodology: Bacterial isolates was characterized using standard microbiological and biochemical tests for the phenotypes, and 16S rDNA for the genotypes. Isolates were also screened for PHA potentials using specific primers.
 Results: Genetically identified Bacillus cereus strains LB17 and Bacillus paramycoides SA27 were phenotypically identified as Bacillus badius. Similarly, Acinetobacter calcoaceticus JL11, five strains of Alcaligenes faecalis, seven strains of Bacillus spp., Enterobacter cloacae, Falsochrobactrum ovis, Ochrobactrum ciceri, Providencia stuartii including two species of Pseudomonas and Bordetella trematum were all phenotypically identified as Corynebacterium kutsceri. Invariably, Alcaligenes faecalis (strains PSD10 and DEP8), Pseudomonas aeruginosa (H47921) and Vagococcus fluvialis (AWW1) were identified as Staphylococcus species. All 34 bacterial isolates expressed phaC genes for PHA potential, while Alcaligenes faecalis strains and Bacillus humi (NBPP9) expressed phaC1 for short PHA chain.
 Conclusion: This study established variations in the genetical identity of Corynebacterium kutsceri, Enterobacter amnigenus, Micrococcus luteus, Micrococcus varians, Staphylococcus epidermidis and Staphylococcus saprophyticus when compared with the phenotypic identification methods. But, there was synchronization in the genotypic and phenotypic identity of bacillus species. Records of varietal differences of PHA potential were also obtained from same species in this research. It is therefore pertinent to rely on the genetic identification of bacteria for the effective determination of PHA-producing character as displayed in Bacillus spp.

The dynamics of microorganisms and their association with clam in fresh water ecosystem

Clams are shelled marine or fresh water mullusks belonging to the class Bivalvia. They are invertebrates with shells divided into two pieces called valves. They are rich source of proteins and minerals especially calcium and are recommended in the diet of pregnant women and in protein deficient cases. They inhabit the bottom of fresh water bodies or slow running waters. Fresh water is one which contain less than 0.5 parts per thousand of dissolved salts or other impurities, and are found in fresh water lakes, swamps and some rivers. The deposition of litter, substrates and other faecal materials in water body results in a build-up of pathogenic microorganism (bacteria) in the water which gives high burden on the water inhabitants including clams. The concentration of the bacteria in the water body varies with the season. This research was therefore aimed at accessing the type and density of bacteria and fungi present in fresh water associated with clams, and to determine the effect of the microorganism on the nutritional value of clams over a period of ten months in a fresh water ecosystem. Samples for analysis were water from Itu river, labeled sample A, sample B was water used to rinse the clams, sample C was homogenized clam intestine while sample D was homogenized body of the clam. The microbial load was determined using serial dilution and plating methods. Characterization and identification of microbial isolates was done using different standard biochemical tests, to determine; colonial morphology, Gram staining reaction, spore stain, motility, sugar fermentation, production of indole, coagulase and catalase. The methods as outlined by Association of Official Analytical Chemistry were used for physicochemical and nutritional analysis to test for moisture content, ash content, crude protein, fibre, fats and mineral elements. Results of the various analysis showed that, the total microbial count for the four samples through the ten months sampling period was highest in February with sample C having the highest of 1.2 X 105 cfu/mL, followed by sample D 7.0 X 104 cfu / mL, sample B had 5.8 X 104 cfu / mL while sample A was the lowest with 4.4 X 104 cfu / mL. The count was lowest in the month of September with C having 3.7 X 104 cfu / mL, followed by D with 2.4 X 104 cfu / mL, B had 8.0 X 103 cfu / mL while A the lowest was 4.0 X 103 cfu / mL. Microorganisms present in the fresh water sample and clam were mostly coliform from faecal matter and include; Staphylococcus aureus, Enterobacter aerogenes, Spirosoma lingual, Bacillus cereus, Lactobacillus plantarum, Escherichia coli, Flavobacterium aquatile and Micrococcus varians. We conclude that microbial load was higher in dry season than in rainy season probably due to dilution of the water and its velocity during rainy season. Results also showed that the nutritional values of the clam varies with season and density of microbial load. We recommend proper sanitation in water where clams are harvested and proper boiling of clams and possible removal of the intestine before consumption especially during the dry season.

Isolation & Identification of Microbiota Present in Different Probiotic Samples & Test Against Commercially Available Antibiotics

Probiotic bacteria are primarily offered in fermented foods, and dairy products which plays an important role as probiotic carriers. For various reasons, functional dairy foods are highly adapted to promote probiotics' favorable health image: (i) Fermented foods, particularly dairy products, have a positive health image due to their centuries-long use; (ii) people are aware that fermented foods contain living microorganisms; and (iii) probiotics are used as a starter to combine the positive images of fermentation and probiotic cultures. Probiotics are live bacterial formulations (food or medication) that have been clinically proven to improve human health. The majority of probiotics work by regulating mucosal barrier function and immunological activity. The human digestive tract and intestinal microbiota are specialized targets and possess certain characteristics of probiotics. In this research, commercially available antibiotics and separated microorganisms from them by culturing them in various nutritional media. The antibacterial activity was then observed. Different biochemical tests have been performed on samples to identify the types of bacteria present. The bacteria identified from pickle, lassi, watermelon, soy sauce were Micrococcus varians, Pseudomonas aeruginosa, Vibrio species, Lactobacillus fermenti, respectively. The antimicrobial activity of different antibiotics was tested against the isolated microbes from which cefolac-200 shows greater zone of inhibition against Pseudomonas aeruginosa (26.75 mm) lowest zone of inhibition against Lactobacillus fermenti (11.5 mm). Azithromycin and CV-625 does not show any zone of inhibition against Micrococcus varians. Some future studies should be performed to use these isolates reliably including molecular techniques like 16S rRNA sequencing for accurate identification of lactic acid bacterial species.

Microbiological investigation of bacteria in raw eggs obtained from Obafemi Awolowo University, Nigeria

This study aimed to investigate the bacterial load and antibiotic susceptibility of bacteria isolated from uncooked eggs, with the goal of assessing potential health risks associated with their consumption. Six uncooked egg samples were collected, including samples from the eggshell, egg yolk, egg albumen, and their mixture. Bacterial enumeration was performed using the serial dilution and pour plate method on nutrient agar and MacConkey agar. Bacterial isolates were identified based on morphological and biochemical characteristics using Bergey's Manual of Determinative Bacteriology. Antibiotic susceptibility testing was conducted using the disc diffusion method on Mueller Hinton agar. The mean total bacterial load in the egg samples ranged from 3.6 x 10^4 to 5.0 x 104 CFU/ml, with coliforms ranging from 2.5 x 103 to 3.0 x 104 colony-forming unit per ml. A total of 48 isolates were obtained and identified, consisting of 13 Gram-negative and 35 Gram-positive bacteria. The identified bacteria exhibited varied susceptibility and resistance patterns to antibiotics. Gram-negative bacteria showed 100% susceptibility to gentamycin, ofloxacin, pefloxacin, and ciprofloxacin, except for Neisseria denitrificans, while demonstrating 100% resistance to nitrofurantoin, augmentin, and ceftriaxone. Most Gram-positive bacteria were susceptible to Pefloxacin and Streptomycin. Some isolates displayed resistance to multiple antibiotic classes, with Micrococcus varians and Bacillus laterosporus showing resistance to 6 and 7 different classes of antibiotics, respectively. The study findings emphasize the potential health risks associated with consuming uncooked eggs due to the presence of multiple antibiotic-resistant bacteria. These findings highlight the importance of proper cooking and handling practices for eggs to minimize the risk of foodborne infections caused by antibiotic-resistant bacteria. It underscores the need for awareness and implementation of appropriate food safety measures to safeguard public health.

Phytogenic effect of garlic (Allium sativum), ginger (Zingiber officinale) and roselle (Hibiscus sabdariffa) on the keeping quality of shredded meat

The qualities of meat during storage are deteriorated by microbial growth, oxidation and enzymatic autolysis. Garlic and ginger are recipes used in meat product preparation as antimicrobial and antioxidant substances. .A total of sixty 6-week old broiler chickens were sacrificed and meat removed from the breast muscle where meat chunks were randomly distributed into six treatments. Treatments comprised of shredded meat prepared with a standard recipe containing ginger and garlic (SR-GaG), standard recipe without ginger and garlic (mGaG), standard recipe with ginger (pGin), standard recipe with roselle (pRos), standard recipe with garlic (pGar) and standard recipe with vitamin E (pvE) replacing ginger and garlic respectively. Data were obtained for Moisture, Crude Protein, CP, Crude Fat, CF, Ash, Thiobarbituric Reactive Substances, TBARS) for 0, 7 and 14days refrigerated (4oC) storage including Total Bacterial Count (TBC), Total Fungi Count (TFC) and Total Coliform Count(TCC) for 7, 14 and 21 days refrigerated storage. Data were subjected to analysis of variance using IBM SPSS version 21.. Reduced (p < 0.05) moisture content was observed in group mGaG followed closely by pGin group over 14 days of storage. Significantly higher (p < 0.05) CP was recorded in pGin and pvE groups. Reduced (p < 0.05) CF was observed in pvE group at 7thday while pRos group showed reduced CF among the phytogenics and through the storage periods. The TBARS of pGin, pRos, and pGar reduced (p <0.05) along storage periods. The TBC, TCC, and TFC significantly reduced for shredded meat (mGaG and pGin) while elevated values were observed for other treatments across the storage periods. Listeria salivarius and Micrococcus varians were isolated in SR-GaG throughout the storage periods. Therefore, single addition of ginger and garlic to recipe of shredded meat is recommended for oxidative stability, improved meat quality and meat preservation.

Isolation and identification of microorganisms associated with Jollof rice sold at Bukateria in Obafemi Awolowo University, Ile -Ife, Osun State, Nigeria

This study assessed the microbiological quality of Jollof rice by isolating, identifying and characterizing the microorganisms associated with jollof rice. Six replicate samples were collected from different locations in Obafemi Awolowo University campus, Ile-Ife, Osun-State, Nigeria. Maconkey, Nutrient and Potatoes Dextrose agars were used for the isolation and determination of microbial load. Standard morphological and biochemical tests were carried out for the identification and characterization of isolates. A total of 10 bacteria and 10 fungal species were isolated. The total bacterial count ranged from 3.6×103cfu/g to 1.54×105cfu/g, while the total fungal count ranged from 1.04×104sfu/g to 3.0×105sfu/g. The organisms presumptively identified with the percentage occurrence include; Staphylococcus saprophiticus (20%), Proteus vulgaris (10%), Bacillus subtlis (10%), Proteus mirabilis (10%), Micrococcus varians (10%), Bacillus licheniformis (10%), Bacillus cereus (10%), Bacillus polymyxa (10%), Micrococcus luteus (10%) for bacteria isolates and Aspergillus niger (30%), Aspergillus oryzae (30%) and Aspergillus candidus (40%) for fungi isolates. Good personal hygiene, proper sanitation practice and the use of clean utensils during food preparation are recommended to avoid food poisoning and spoilage.

THE AMINO ACID COMPOSITION OF MEAT PRODUCTS TREATED WITH PREPARATIONS OF MICROBIAL ORIGIN

Fermentation in the technology of dry-cured meat products helps to create products with high sensory characteristics and an extended shelf life. The purpose of this work was to study how bacterial and enzyme preparations affected the accumulation of free amino acids in dry-cured meat products.
 The work considers how the preparation Iprovit-Lakmik based on the cultures L. plantarum, L. rhamnosus, L. casei, and Micrococcus varians acts on the accumulation of free amino acids during the ripening of dry-cured sausages, and how the bacterial preparation Iprovit-MKS based on the cultures Lactoba plantarum, L. rhamnosus, and Staphylococcus simulans and the enzyme preparation Protolad acts on proteolysis during the ripening of dry-cured whole-muscle products from pork and beef. Fermentation was carried out in a climatic chamber at a temperature required by the technological process of accelerated ripening of fermented sausages, using bacterial and enzyme preparations. The starter culture Iprovit-Lakmik was added in the amount 0.05% to the volume of the sausage mince prepared in accordance with the formulation of the dry-cured sausage Zhytomyrska. The preparations Protolad and Iprovit-MKS were added at the stage of injecting the balyk (cured fillet) Darnitsky. Samples with no preparations added were the controls. The amino acid composition of proteins was determined by ion-exchange chromatography on an automatic amino acid analyser Biotronik LC2000. The total content of free cyclic amino acids was determined by the Hull method, and that of acyclic amino acids by the Gomez method, using colourimetry.
 It has been found that after fermentation, each product had its own characteristics of the qualitative and quantitative accumulation of free amino acids. Adding the preparation Iprovit-Lakmik to raw meat allowed directed biochemical transformations with the formation of a significant amount of free amino acids, which exceeded the control by 115.86 mg/100 g of dry matter. The enzyme preparation Protolad has a positive effect on the chemical and physicochemical characteristics of salted products from pork and beef. It has been proved that its use activates the breakdown of muscle tissue proteins and increases the pool of free amino acids. In the test samples from pork and beef, the content of free amino acids increased, respectively, by 1.7 times and 3.4 times, and that of non-essential amino acids by 1.4 times and 1.3 times respectively, compared with the control. In the samples with the bacterial preparation Iprovit-MKS, the total amount of amino acids increased significantly: by 32% for beef balyk and by 20% for pork balyk.

A Treatment Option or Source of Bacterial Pathogen Transmission? The Case of Herbal Mixture in Nigeria

Herbal mixture such as agbo, has been used in recent years in Nigeria to treat various sicknesses including malaria, typhoid, dysentery and cholera. However, the bacteriological quality and safety is of paramount importance spurring the argument whether it is treatment option or sources of pathogen transmission. Hence this study was conducted to investigate the bacteriological analysis of agbo herbal preparations. Samples of herbal mixture were purchased from five different markets (Uselu, New Benin, Oba, Santana and Ogida Markets) in Benin City, Edo State, Nigeria. Bacteriological analysis was carried out using pour plate isolation method. Identification of isolated bacteria was based on their cultural, morphological, biochemical and molecular techniques. Antibiotic sensitivity pattern was carried out using disk diffusion method. The plasmid profile of multiple drug resistance bacterial genes isolated was also analyzed. Bacteriological analyses showed that the total bacterial counts (TBC) of all the test herbal samples obtained from the various markets ranged from 0.04 x 104 to 1.13 x 104cfu/ml. Eight bacterial species were identified and they include; Bacillus cereus, Bacillus subtilis, Escherichia coli, Lactobacillus casei, Serratia marcescens, Micrococcus varians, Pseudomonas aeruginosa and Staphylococcus aureus. The least occurring bacterial isolates were Serratia marcescens and Pseudomonas aeruginosa (5.26%) while the highest occurring was Bacillus cereus (21.05%). Isolated bacteria were resistant to commonly used antibiotics. Plasmid profile revealed presence of plasmid genes in the bacterial isolates. Since applications of herbal medicines for curative purposes is on the increase, there is need to monitor and ensure its bacteriological quality before distributing to final consumers.

Effects of Fizzy Drinks on Blood Sugar Level, Sputum and Enteric Bacterial Populations in Healthy Human Beings

Fizzy drinks are non-alcoholic beverages typically containing water, sweetener, carbon dioxide, acidulates, flavourings, colourings, chemical preservatives, antioxidants, and/or foaming agents. They are usually characterized by a high C/N ratio and low pH, which allows the growth of specific microbial groups while limiting others. Blood sugar level, sputum, and faecal samples were collected from twenty healthy students (pre and post-fasting) and analyzed microbiologically to determine the effect of the consumption of fizzy drinks on the body’s enteric bacteria population. Samples were processed and cultured using pour plate and streak plate techniques in three selective media consisting of Maconkey agar, Salmonella Shigella agar, and Eosin Methylene Blue agar. Differentiation and isolation of various isolates were based on gram-staining technique after culturing for 24 hours at 37ºC and biochemical reactions using MICROBACT 12A/12B and 24E identification kits. Following consumption of fizzy drinks 35cl for females and 60cl for males, results show there was no significant difference between pre and post fasting blood sugar levels (84.2 and 85.7) and (90.7 and 118.1) mg/dl in males and females respectively. In females, post-consumption blood sugar level was higher (86.6 to 82.0) mg/dl in the Bigi Lemon group compared with lower post-consumption blood sugar level (84.8 to 86.4) mg/dl in Bigi Orange group. Among males, post-consumption blood sugar level was higher in both Coke and Fanta groups (93.6 to 123.8 and 87.8 to 112.4) mg/dl respectively. The average oral microbial load from sputum samples reduced in both males and females (1.90 to 0.93× 105) and (1.52 to 0.44× 105) cfu/g respectively post consumption. Post consumption, sixty-three bacterial isolates comprising eight organisms in sputum with the following percentage prevalence were detected, namely: Micrococcus varians (18.18%), Staphylococcus saprophyticus (3.030%), Micrococcus acidophilus (21.212%), Bacillus macerans (18.18%), Bacillus cereus (9.09%), Staphylococcus aureus (9.09%), Streptococcus pyogenes (3.030%) and Bacillus subtilis (18.18%), while in faecal samples with the following bacteria with the following percentage prevalence were isolated: Staphylococcus aureus (7.94%), Escherichia coli (25.40%), Klebsiella (20.63%), Shigella (17.46%) and Salmonella (28.57%).

Microbial studies of biosurfactant producing bacteria from crude oil contaminated soil

Soils contaminated with crude oil collected from three sites in Delta State were analyzed using serial dilution and pour plate methods. The physicochemical characteristics of the soil were determined using standard methods. The mean heterotrophic bacteria count and the mean hydrocarbon utilizing bacteria count were also determined. Blood haemolysis, foaming activity, oil spreading techniques and emulsification assay was used to screen the microorganisms for biosurfactant production. The biosurfactant producing bacteria were selected and their effect on metal removal and growth kinetics was also determined. The pH of the contaminated soil samples ranged 4.82 to 5.62. The mineral elements such as potassium (k+) and sodium (Na+) ranged from 0.20 to 0.80 Meq/100g and 0.07 to 0.81 Meq/100g respectively. The heavy metal content such as zinc (Zn2+) and lead (Pb2+) ranged from 10.13 to 19.24 mg/kg and 19.24 to 49.63 mg/kg respectively. Organic carbon and THC ranged from 5.44 to 6.87 % and 2720.00 to 3110.00 mg/kg respectively. The mean heterotrophic bacteria and hydrocarbon utilizing bacteria ranges from 1.4 ± 0.4 x 106 to 1.6 ± 0.7 x 106 and 1.0 ± 0.2 x 106 to 1.2 ± 0.4 × 106 respectively in the soil samples. Bacteria isolated and identified from the three sites include Corynebacterium spp., Bacillus subtilis., Pseudomonas aeruginosa, Micrococcus varians, Streptococcus spp., Klebsiella spp. and Enterobacter spp. with Bacillus subtilis and Pseudomonas aeruginosa having the highest prevalence and among these isolates only Corynebacterium spp., Bacillus subtilis., Pseudomonas aeruginosa and Micrococcus varians showed positive result for the production of biosurfactant. Bacillus subtilis had the highest metal removal capacity of 29.44% of 100 ppm of lead. Corynebacterium spp. and Bacillus subtilis had an optimum growth at pH 8 and 7 respectively while Pseudomonas aeruginosa and Micrococcus varians has an optimum growth at pH.

Spatial Distribution and Isolation of Microbiota Associated with Spoilage of Tomatoes Sold in Selected Markets in Nasarawa State, Nigeria

Tomato (Lycopersicum spp) is widely consumed universally because of its high nutritive value, but suffers great post-harvest losses due to microbial attack. This work was carried out to investigate the causative agents of tomato spoilage and the spatial distribution of such causative agents in some selected major markets in Nasarawa State, Nigeria. Sixty tomato fruits from each of the four selected markets (total of 240 fruits) were investigated for the microorganisms responsible for tomato fruit spoilage. Eleven microorganisms, comprising of five bacterial species and six fungal species were isolated from the spoilt tomatoes. The bacterial isolates included Micrococcus varians, Lactobacillus fermenti, Escherichia coli, Salmonella sp and Klebsiella sp. The isolated fungi included Rhizopus stolonifer, Fusarium oxysporium, Aspergillus flavus, Geotrichum candidum, Mucor mucedo, and Candida tropicalis. They were all positive for the pathogenicity test. The isolated organisms were heterogeneously distributed with remarkable levels of severity across the study area. The bacterial load ranged between 2.09 X 109 and 2.56 X 109, while the fungal load ranged between 2.72 X109 and 3.97 X 10 9. The occurrence and magnitude of the spoilage, and hence economic loss due to microbial attack could be attributable to the biologic, ecologic and environmental factors of the study area. Recommendations were, therefore, made for improved personal and environmental hygiene, good agricultural practice and proper treatment of tomato fruits before consumption to avert the imminent health consequences due to the spoilage microorganisms.

Bioburden in sleeping environments from Portuguese dwellings.

A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and after sleeping and bioburden. In addition, and driven by the lack of information regarding fungi azole-resistance in Portuguese dwellings, a screening with supplemented media was also performed. The most prevalent genera of airborne bacteria identified in the indoor air of the bedrooms were Micrococcus (41%), Staphylococcus (15%) and Neisseria (9%). The major indoor bacterial species isolated in all ten studied bedrooms were Micrococcus luteus (30%), Staphylococcus aureus (13%) and Micrococcus varians (11%). Our results highlight that our bodies are the source of the majority of the bacteria found in the indoor air of our homes. Regarding air fungal contamination, Chrysosporium spp. presented the highest prevalence both in after the sleeping period (40.8%) and before the sleeping period (28.8%) followed by Penicillium spp. (23.47% morning; 23.6% night) and Chrysonilia spp. (12.4% morning; 20.3% night). Several Aspergillus sections were identified in air and EDC samples. However, none of the fungal species/strains (Aspergillus sections Fumigati, Flavi, Nidulantes and Circumdati) were amplified by qPCR in the analyzed EDC. The correlations observed suggest reduced susceptibility to antifungal drugs of some fungal species found in sleeping environments. Toxigenic fungal species and indicators of harmful fungal contamination were observed in sleeping environments.

Selling Points of Sewage Sludge as an Enhancing Agent of Bioremediation of Diesel Oil-Polluted Soil

Bioremediation employing the action of microbes alone has been shown to be inadequate. The aim of this study was to evaluate the efficacy of sewage sludge (SS) in enhancing bioremediation of diesel oil-polluted soil. Diesel oil was introduced into the soil at the concentration of 10 % (v/w) and mixed with 5%, 10% and 15% (w/w) of sewage sludge. The remediation of the oil was determined gravimetrically and spectrophotometrically using n-hexane as extractant. Effectiveness of the remediation strategy was assessed by the seed germination toxicity test At the end of forty-two days, 32.22 % oil loss was recorded in the unamended polluted soil while 58.33% oil loss was recorded in the soil amended with sewage sludge. Hydrocarbon- utilizing bacteria (HUB) counts were significantly high (P≤0.05) in the sewage sludge-amended options, ranging from 5.3 ±0.9 x 106 to 12.3±0.75 × 106CFU/g soil, as compared to the unamended control soil which gave 1.0 × 106- 3.8 × 106CFU/g of soil. The hydrocarbon- utilizing bacteria isolated from both the control and amended soils were identified tentatively as Bacillus cereus, Pseudomonas putida, Micrococcus varians, Corynebacterium spp and Staphylococcus spp based on their cultural, morphological and biochemical characteristics. The fungal counts in the SS-amendment options were also higher than was recorded in the control option ranging from 3.8 x 105 ± 0.2 to 11.6 x 105 ±0.25. Aerobic fungi isolated were Aspergillus niger, Aspergillus flavus, Fusarium sp, Cladosporium sp and Penicillium sp. The highest oil loss and germination indices were recorded in SS-amended options. There was a significant difference (P≤0.05) in oil loss and germination index between the unamended control soil and polluted soil amended with 15% SS.

INVESTIGATION OF MICROBIOLOGICAL QUALITY OF SELECTED STREET VENDED FOODS SOLD IN UYO METROPOLIS, AKWA IBOM STATE, NIGERIA

Street vended food play an important role in developing societies as they support livelihood of millions of people in the society. This study evaluated the microbial quality of selected street-vended foods in Uyo Metropolis, Akwa Ibom State, Nigeria. Popular food samples were collected from five different locations with intensive vending activities and analyzed for total bacterial count (TBC), total Salmonella (TSC), E. coli and Vibrio cholera counts (VCC). Results indicated that TBC ranged from 1.33 x 105 + 0.03 cfu/g to 6.00 x 105 + 0.03 cfu/g while TSC ranged from 1.00 x 103 + 0.02 cfu/g to 3.00 x 104 + 0.04 cfu/g. Total E.coli count ranged from 1.00 x 101 + 0.00 cfu/g to 2.09 x 103 + 0.01 cfu/g which was above WHO standard of 0 cfu/g. VCC was detected in 7 food samples with the highest count being 7.20 x 102 + 0.02 cfu/g. There were significant differences (P<0.05) in microbial counts among food samples and vending locations. Bacterial species isolated from the food samples include: Aerococcus viridans, Cornynebacterium uberis, Escherichia coli, Klebsiella species, Lactobacillus salivarius, Micrococcus luteus, Micrococcus varians, Proteus mirabilis, Pseudomonas pyogenes, Pseudomonas pyogenia, Salmonella paratyphi, Salmonella typhi, Staphylococcus albus, Staphylococcus aureus, Staphylococcus epidermidis, Vibrio cholera. Data obtained from the questionnaires showed poor handling and preparation of food by vendors, hence the need to train and educate vendors on food hygiene. Application of hazard analysis and critical control point (HACCP) is necessary to improve the safety of street foods and consequently safety of consumers.

Испытание иммобилизованных микроорганизмов-нефтедеструкторов в полевых условиях месторождения Жанаталап Атырауской области

Hydrocarbon-oxidizing microorganisms are widespread in natural ecosystems, since the ability to oxidize hydrocarbons is associated with the presence of enzymes of the oxidase group, with microorganisms using oil and oil products as the sole source of carbon and energy in the microbiological decomposition of hydrocarbons. The decomposition of oil and oil products in the soil under natural conditions is a biogeochemical process in which the functional activity of a complex of soil microorganisms that ensure the complete mineralization of oil and oil products to carbon dioxide and water is of crucial importance. The search for effective indigenous hydrocarbon-oxidizing microorganisms, the creation on their basis of a full-fledged specialized consortium of microorganisms and their introduction into the initial, cleaned environment is one of the promising methods of purification with oil pollution in the oil-producing regions of Kazakhstan. Among the new biological methods for cleaning soil from oil pollution, the most promising are the use of a consortium based on immobilized microorganisms. A correctly selected carrier capable of sorption of petroleum hydrocarbons preserves and maintains attached cells in a viable state for a long time and protects them, especially at the initial stage of introduction, from adverse environmental conditions, which increases the efficiency of oil destruction. Hydrocarbon-oxidizing microorganisms have high emulsifying activity and sorption ability for expanded clay, optimal conditions for biomass accumulation are: temperature 28-30 °С, pH = 7 and 9. It is recommended to use a consortium of oil-degrading microorganisms based on the native strains of cultures Bacillus firmus S20, Bacillus subtilis PR28, Micrococcus roseus UD6-4, Micrococcus varians PR69 to clean the soils contaminated with oil and oil products in the Zhanatalap field in the Atyrau region. It should be noted that after 8 months at the Zhanatalap field in the Atyrau region, oil destruction amounted to 94.3% in the variant with the introduction of immobilized microorganisms on zeolite and expanded clay. The results of the research are the basis for further development of technology for the restoration of oil-contaminated soils in arid conditions of Kazakhstan.

Bacterial quality assessment of drinking water for layer chicken managed under battery cage and deep litter systems from Sokoto Metropolis, Nigeria

This study assessed the bacterial quality of drinking water for layer chicken managed under battery cage (BC) and deep litter (DL) systems in Sokoto Metropolis. A total of 18 samples were collected from the two systems. Serial dilution, spread plate innoculation, colony count, subculturing, gram staining and biochemical characterization were carried out according to standard methods .The mean count concentrations in BC (1.4×10 6 , 7.2×10 6 and 3.4×10 6 ) were relatively higher than those recorded in DL (1.57×10 7 ,4.52×10 7 , and 1.2×10 6 ) .The mean count (CFU/ml)for BC was 72.11111 and that of DL was 207.4444.The bacteria determined in BC were: : Bacillus species, Micrococcus varians , Corynebacterium xerosis and Lactobacillus fermenti ; whereas, those determined in DL were Micrococcus varians , Lactobacillus fermenti , E. coli , and Corynebacterium xerosis ; thus E.coli was only recorded in DC, but the rest were found in both BC and DL. In BC, the most frequent was Corynebacterium xerosis , then Micrococcus varians , and lastly Bacillus species and Lactobacillus fermenti ; whereas, in DL Corynebacterium xerosis was also most frequent, then Micrococcus varians ,then the rests. Thus, C. xerosis was the most overall prevalent, then Micrococcus varians , then the rests. This work depicted that water used in the BC and DL systems surveyed contains a higher and diverse concentration of bacteria .This portend of contamination and unsanitary outcome is capable of harming the health, production, and ultimately the public health. More water treatment innovative methods should be use, regular and proper cleaning of farm and drinkers are needed and farmers need to be educated. Keywords: water quality, Corynebacterium xerosis , Lactobacillus fermenti , S okoto metropolis , Bacillus species

Characteristics of airborne bacteria and fungi in the atmosphere in Ho Chi Minh city, Vietnam - A case study over three years

The purpose of this study was to determine and assess airborne microbial characteristics (bacteria and fungi) in Ho Chi Minh City (HCMC), Vietnam, from 2014 to 2016, as well as identify seasonal variation trends. Airborne samples were collected passively and actively from four different environmental sites: the zoo, road, rural, and urban areas. The major bacterial genera identified were Bacillus siamensis, Staphylococcus aureus, Micrococcus varians, and Enterobacteriaceae. Some airborne fungi (Aspergillus sp., Penicillium janthinellum, and Fusarium solani) were found during the wet and dry seasons. In rural and residential areas, airborne bacterial and fungal bioaerosol levels were higher during weekends than weekdays. A linear model illustrated the significant effect of the environmental factors CO2 level, temperature (TEMP), and relative humidity (RH) on both bacterial and fungal counts. There was a positive relationship between microbial sampling types especially between microbial concentration and CO2 level and TEMP (p < 0.05). The linear models explained a certain percent of the variation in bacterial and fungal concentration in terms of CO2, TEMP, and RH on the roadside (Dien Bien Phu – Dinh Tien Hoang intersection), the zoo (Saigon Zoo and Botanical Garden), the residential area, and the rural area. These insights into bacteria and fungi levels can be used to aid future health studies, policy making, and urban planning in HCMC.

Biodegradation of Hexavalent Chromium from Paint Industry Effluent by Indigenous Bacteria

Hexavalent chromium (Cr-VI) is toxic, mutagenic and carcinogenic chemical, whereas its reduced trivalent form (Cr-III) is much less toxic. Cr-VI is widely used in paint industry, tannery industry, and so on. In the present study an attempt was made to isolate naturally occurring bacteria from paint industry effluent possessing high potentiality to reduce Cr-VI. Seven efficient chromium reducing bacterial strains were isolated as Bacillus korlensis, Bacillus subtilis, Bacillus cereus, Micrococcus luteus, Micrococcus varians, Enterobacter intermedius and Tatumella terrea. These bacteria reduced chromium in culture media at maximum 5 mM concentration within a period of 24–72 h as determined by 1, 5-diphenylcarbazide (DPC) colorimetric method. However, significant Cr-VI reduction or biodegradation was observed at 1.25 mM substrate concentration within 24 h at 37°C. The research was very promising for development of a microbiological process to be used in the removal of toxic hexavalent chromium from the environment.