Violet Red Bile Agar Research Articles

Monitoring Multi-Drug Resistant Klebsiella pneumoniae in Kitagata Hot Spring, Southwestern Uganda: A Public Health Implication.

The concerning frequency of K. pneumoniae in various recreational settings, is noteworthy, especially regarding multi-drug resistant (MDR) strains. This superbug is linked to the rapid spread of plasmids carrying these resistance genes. The objective of this study was to evaluate the spatiotemporal prevalence of MDR-K. pneumoniae in the Kitagata hot spring, Southwestern Uganda. A laboratory-based descriptive longitudinal study was conducted between May and July 2023. During rainy and dry seasons, we collected eighty water samples in the morning and evening from the hot spring. The temperature at each point was measured prior to sample collection, and two samples were obtained at varying depths. 5 mL of each homogenized sample were pre-enriched in brain heart infusion broth, and subsequently in both blood and violet red bile agar. The Kirby-Bauer disk diffusion method was performed, followed by the detection of carbapenemase (CR) and extended-spectrum β-lactamase (ESBL) production. Polymerase chain reaction showed resistance genes viz. bla TEM, bla CTX-M and bla KPC. Data were analyzed using SPSS-20 to obtain chi-square tests and regression analysis. K. pneumoniae accounted for 30.0% of isolates obtained from Kitagata hot springs, with all isolates classified as multi-drug resistant. All isolates were resistant to ampicillin, rifampicin, ceftazidime, and azithromycin (79.2%). Additionally, 95.8% of isolates harbored bla TEM gene alone and both bla TEM and bla CTX genes, followed by bla KPC alone (33.3%), with 25% harboring all three resistance genes. During the dry season, K. pneumoniae had a higher prevalence (35.0%) compared to the wet season (25.0%). The prevalence of MDR-K. pneumoniae significantly increased over the course of the study. The presence of the three studied resistance genes in the isolates showed a positive correlation with the second phase of sample collection and the dry season but exhibited a negative correlation with temperature, except for isolates harboring either bla TEM alone or bla TEM+KPC+CTX genes. Kitagata hot spring serves as a hotspot for continuous dissemination and acquisition of MDR-K. pneumoniae harboring resistance genes that encode for ESBL and CR production. The healthcare sector ought to implement an ongoing monitoring and surveillance system as well as robust antimicrobial resistance stewardship programs aimed at delivering health education to the community.

Antimicrobial susceptibility profile of Klebsiella pneumoniae isolated from some dairy products in Libya as a foodborne pathogen.

Klebsiella pneumoniae is one of the most common causes of clinical and asymptomatic mastitis in dairy cattle, as well as in milk and dairy products that affect milk quality. Mastitis caused by K. pneumoniae is even more serious due to its poor response to antibiotic therapy. The aim of this study was to detect and identify the presence of K. pneumoniae in milk and dairy products produced in Libya. A total of 234 samples were randomly collected from various locations in Libya. Samples were examined for the presence of K. pneumoniae using conventional cultural techniques, including cultivation in violet red bile agar plus 4-methylumbelliferyl-ß-D-glucuronide broth and CHROM agar, followed by polymerase chain reaction identification and partial sequencing of 16S rRNA. Of the 234 samples of milk and dairy products collected, 16 (6.8%) isolates revealed mucoid colonies on agar media that were phenotypically suggested to be K. pneumoniae. Identification of isolates was confirmed using molecular techniques (16S rRNA). Among the examined samples, K. pneumoniae was recovered from camel's milk, raw cow's milk, raw fermented milk, Maasora cheese, Ricotta cheese, soft cheese, full cream milk powder, milk powder infant formula, cereal baby food, and growing-up formula. Antibiotic susceptibility testing was performed on 12 of the 16 K. pneumoniae isolates, and the results showed that K. pneumoniae isolates were resistant to more than eight antibiotics; interestingly, two isolates showed metallo-beta-lactamase (MBL) production. K. pneumoniae is considered a risk to human health because many of these products do not comply with the microbiological criteria of international and/or Libyan standards. This study emphasized the relationship between K. pneumoniae and raw milk, cheese, milk powder, and infant milk retailed in Libya. There is a need to take the necessary measures to ensure effective hygiene practices during production in dairy factories, handling, and distribution on the market, in particular at a small local production scale.

Microbiological quality of water samples obtained from water sources in Ishaka, Uganda.

This study aimed to evaluate the microbiological quality of water sources in Ishaka division, Bushenyi district. Water from taps, wells and springs were sampled for the cross-sectional investigation. The enumeration and identification of microbes (Escherichia coli, Salmonella, Shigella, Proteus, Staphylococcus aureus and total coliforms) in water samples were carried out using a variety of methods. Escherichia coli was enumerated using the membrane filtration method; Salmonella, Shigella and Proteus using a two-step enrichment method; Staphylococcus aureus using the surface spread method and total coliforms using the most probable number technique. Mannitol salt agar was used for enumeration of Staphylococcus Aureus and violet red bile agar was used for enumeration of total coliforms and Escherichia coli; xylose lysine deoxycholate agar was used for both Salmonella spp. and Shigella spp. API-20E was used to phenotypically identify the Enterobacteriaceae contaminants in water. These included Escherichia coli, Proteus mirabilis, Proteus vulgaris, Salmonella spp. and Staphylococcus aureus. Escherichia coli counts in the water from springs and wells ranged from 0 to 314 cfu/mL (p = 0.173) and 0 to 3 cfu/mL (p = 0.269), respectively, while tap water had no incidence of Escherichia coli. Highest level of bacterial contamination in water sources, beyond acceptable WHO (0 cfu/100 mL) limits for drinking water, was reported: Proteus spp., 34 (54.8%), followed by total coliforms, 24 (38.7%), Shigella spp., 22 (35.5%) and least were Salmonella spp. (8.1%) and Staphylococcus aureus spp. (8.1%). It is therefore concluded that spring and well community water sources in Ishaka division, Uganda, are significantly contaminated with pathogenic bacteria and thus unsafe for drinking without adequate water treatment (disinfection and filtration).

Tea contamination by mycotoxins and azole-resistant mycobiota – The need of a One Health approach to tackle exposures

Despite tea beneficial health effects, there is a substantial risk of tea contamination by harmful pathogens and mycotoxins. A total of 40 tea samples (17 green (raw) tea; 13 black (fermented) tea; 10 herbal infusions or white tea) were purchased from different markets located in Lisbon district during 2020. All products were directly available to consumers either in bulk (13) and or in individual packages (27). Bacterial analysis was performed by inoculating 150 μL of samples extracts in tryptic soy agar (TSA) supplemented with 0.2 % nystatin medium for mesophilic bacteria, and in Violet Red bile agar (VRBA) medium for coliforms (Gram-negative bacteria). Fungal research was performed by spreading 150 μL of samples in malt extract agar (MEA) supplemented with 0.05 % chloramphenicol and in dichloran-glycerol agar (DG18) media. The molecular detection of the Aspergillus sections Fumigati, Nidulantes, Circumdati and Flavi was carried out by Real Time PCR (qPCR). Detection of mycotoxins was performed using high performance liquid chromatograph (HPLC) with a mass spectrometry detector. Azole resistance screening was achieved following the EUCAST guidelines. The highest counts of total bacteria (TSA) were obtained in green raw tea (81.6 %), while for coliform counts (VRBA) were found in samples from black raw tea (96.2 %). The highest fungal counts were obtained in green raw tea (87.7 % MEA; 69.6 % DG18). Aspergillus sp. was the most prevalent genus in all samples on MEA (54.3 %) and on DG18 (56.2 %). In the raw tea 23 of the samples (57.5 %) presented contamination by one to five mycotoxins in the same sample. One Aspergillus section Fumigati isolate from green tea beverage recovered form itraconazole-Sabouraud dextrose agar (SDA) medium, presented itraconazole and posaconazole E-test MICs above MIC90 values. Our findings open further discussion regarding the One-Health approach and the necessary investment in researching biological hazards and azole-resistance associated with the production and consumption of tea (in particular green tea).

Transmission pathway of Enterobacteriaceae from reared fish and surrounding environment to water body in Batang Ai reservoir, Sarawak, Borneo

This study was aimed to determine the genetic distribution and characteristics of the bacterial family in the Batang Ai reservoir and their possible sources of transmission into the lake water. Surface water samples were collected from twenty-seven sampling points scattered around the Batang Ai reservoir and four fish samples were obtained from an aquaculture farm located within the water reservoir. The samples were plated on Violet Red Bile Agar (VRBA) plates for the isolation of Enterobacteriaceae. A total of 141 bacterial colonies were isolated from the culture plates and subjected to (GTG)5 PCR analysis to determine the genetic similarities among the isolates. A dendrogram was plotted based on the (GTG)5 PCR patterns and the representative isolates were selected for identity confirmation using 16S rRNA sequencing. Based on the sequencing, five genera of Enterobacteriaceae were identified as Enterobacter, Escherichia, Shigella, Klebsiella and Pseudocitrobacter, consisting of 12 identified species, namely Enterobacter hormaechei, E. hormaechei subsp. xiangfangensis, E. cloacae, E. cloacae subsp. dissolvens, E. kobei, E. tabaci, Shigella boydii, S. flexneri, Pseudocitrobacter faecalis, Escherichia fergusonii, E. coli and Klebsiella pneumoniae. A total of 14 antibiotics from seven anti-microbial classes including penicillins, cephems, monobactams, aminoglycosides, tetracyclines, quinolones and fluoroquinolones, and phenicols were tested against the isolates. A total of seven species within the isolates were found to have multiple antibiotic resistance (MAR) index below 0.2, suggesting those isolates were derived from low risk of antibiotics contamination sources. With the exception of ampicillin and tetracycline, all antibiotics have 25% or less bacterial species displaying resistance. Most (70%) of the bacterial species showed resistance toward ampicillin. The fish isolates demonstrated multiple antibiotic resistance indexes ranging from 0.214 to 0.5. The presence of multiple antibiotic-resistant bacteria in the water reservoir may pose the risk of antibiotic-resistant bacterial infections through water-related activities and consumption of fish harbouring antimicrobial resistance bacterial species. It was proven that Enterobacteriaceae were transmitted from the activities and surrounding environments to the water reservoir, thus it is proposed that a guideline for activities to be carried out in the water reservoir is created and imposed.

Frozen-Phase High-Pressure Destruction Kinetics of Escherichia coli as Influenced by Application Mode, Substrate, and Enrichment Medium.

The synergistic effect of frozen-phase high pressure (HP) on the inactivation of E. coli ATCC 25922 cultures in suspension medium, Chinese bayberry juice (pH 3.0), and carrot juice (pH 6.5) was evaluated. The survivor count of E. coli remained at 3.36 log CFU/mL on a nonselective brain heart infusion (BHIA) medium, while no survivor was detected on a selective violet red bile agar (VRBA) medium after a 5 min hold pressure at 250 MPa in a frozen culture suspension. BHIA was suitable for safe testing of the injured E coli cells after HP treatment in frozen state. Frozen Chinese bayberry juice showed higher sensitivity to HP treatment for its matrix property with high sterilizing efficiency at 170 MPa. Two pulses exhibited a significant inactivation effect in frozen samples compared with one pulse, especially for the Chinese bayberry juice with different pressure levels. The destruction kinetics of HP pulse mode followed the first-order rate kinetics with a Zp value of 267 MPa in frozen carrot juice. Our results evaluated the influenced factors of frozen HP destruction effects, including the medium, substrate, and application mode. The frozen HP destruction kinetics of pulses afford us better understanding of the technology application in the food industry.

Loading Rates of Dust and Bioburden in Dwellings in an Inland City of Southern Europe

Sampling campaigns indoors have shown that occupants exposed to contaminated air generally exhibit diverse health outcomes. This study intends to assess the deposition rates of total settleable dust and bioburden in the indoor air of dwellings onto quartz fiber filters and electrostatic dust collectors (EDCs), respectively. EDC extracts were inoculated onto malt extract agar (MEA) and dichloran glycerol (DG18) agar-based media used for fungal contamination characterization, while tryptic soy agar (TSA) was applied for total bacteria assessment, and violet red bile agar (VRBA) for Gram-negative bacteria. Azole-resistance screening and molecular detection by qPCR was also performed. Dust loading rates ranged from 0.111 to 3.52, averaging 0.675 μg cm−2 day−1. Bacterial counts ranged from undetectable to 16.3 colony-forming units (CFU) m−2 day−1 and to 2.95 CFU m−2 day−1 in TSA and VRBA, respectively. Fungal contamination ranged from 1.97 to 35.4 CFU m−2 day−1 in MEA, and from undetectable to 48.8 CFU m−2 day−1 in DG18. Penicillium sp. presented the highest prevalence in MEA media (36.2%) and Cladosporium sp. in DG18 (39.2%). It was possible to observe: (a) settleable dust loadings and fungal contamination higher in dwellings with pets; (b) fungal species considered indicators of harmful fungal contamination; (c) Aspergillus section Candidi identified in supplemented media with voriconazole and posaconazole; (d) specific housing typologies and (e) specific housing characteristics influencing the microbial contamination.

Microbial analysis and factors associated with contamination of ready-to-eat chili pepper sauce in Buea municipality, Cameroon

Chili peppers sauce is a dietary complement largely consumed in Cameroon. It is consumed in a powder or wet (pepper sauce) form or directly introduced into cooked food. In this study, the microbiological quality of chili pepper sauce used as food complement in the Buea municipality was assessed. The study was an observational and cross-sectional study involving 70 chili pepper sauce samples from food vendors. The samples were cultured on Salmonella-Shigella agar, violet red bile agar, plate count agar and the colonies isolated were enumerated and identified using the Enterosystem 18R. Factors associated with microbial count were identified using a multiple linear regression model. Bacteria isolate from chili pepper sauce were mainly Entrobacter cloacae (31.57%), Citrobacter freundii (15.78%) and Klebsiella pneumonia (15.78%) and other Enterococcal species. Factors associated with bacteria count were: age of the vendor, number of customers served, types of food and food storage conditions (covering, heating, type of storage containers). Chili pepper sauce used as food complement in Buea Municipality were contaminated with Enteric microorganisms and may represents a potential public health hazard to consumers. The presence of these microorganisms from chilli pepper sauce could result from poor handling. Key words: Chili pepper sauce, contamination, enteric bacteria, health hazard.

Environmental and Sex Effects on Bacterial Carriage by Adult House Flies (Musca domestica L.).

Adult house flies frequent microbe-rich sites such as urban dumpsters and animal facilities, and encounter and ingest bacteria during feeding and reproductive activities. Due to unique nutritional and reproductive needs, male and female flies demonstrate different interactions with microbe-rich substrates and therefore dissemination potential. We investigated culturable aerobic bacteria and coliform abundance in male and female flies (n = 107) collected from urban (restaurant dumpsters) and agricultural (dairy farm) sites. Whole-fly homogenate was aerobically cultured and enumerated on nonselective (tryptic soy agar; culturable bacteria) and selective (violet-red bile agar, VRBA; coliforms) media. Unique morphotypes from VRBA cultures of agricultural flies were identified and tested for susceptibility to 14 antimicrobials. Female flies harbored more bacteria than males and there was a sex by site interaction with sex effects on bacterial abundance at the urban site. Coliform abundance did not differ by sex, site or sex within site. Both male and female flies carried antimicrobial-resistant (AMR) bacteria: 36/38 isolates (95%) were resistant to ≥1 antimicrobial, 33/38 were multidrug-resistant (≥2), and 24/38 isolates were resistant to ≥4 antimicrobials. Our results emphasize the role of house flies in harboring bacteria including AMR strains that pose a risk to human and animal health.

Effects of Ozonated Water on Microbial Growth, Quality Retention and Pesticide Residue Removal of Fresh-cut Onions

ABSTRACT The native microflora survival and quality retention of fresh-cut onions treated by ozonated water (OW) with ozone concentration of 1.4 mg L−1, for 1, 3, and 5 min during storage at 4°C for 14 days were investigated. The pesticide residue removal effect of OW treatment for 5 min was also determined. The results show that all OW treatments significantly inhibited the growth of aerobic bacteria, coliforms, and yeasts during storage, with the OW treatment for 5 min allowing the lowest growth rates. OW treatment for 1 min significantly reduced the weight loss of fresh-cut onions during a longer storage time (8–14 d). All OW treatments reduced the respiration rate and the softening of fresh-cut onions, exhibiting better overall quality retention than the control samples. In addition, OW treatment for 5 min significantly reduced the residual levels of five tested pesticides (dimethyl dichlorovinyl phosphate, cypermethrin, chlorpyrifos, methomyl, and omethoate) compared with water treatment. These results indicate that treatment with OW is a promising strategy to control the microbial growth, preserve the quality and reduce pesticide residual of fresh-cut onions. Abbreviations OW: ozonated water; PCA: plate count agar; VRBA: violet red bile agar; PDA: potato dextrose agar; DDVP: dimethyl dichlorovinyl phosphate

Bacterial content and associated risk factors influencing the quality of bulk tank milk collected from dairy cattle farms in Mandalay Region.

To investigate the bacterial content and risk factors associated with the hygienic quality of raw milk, a cross‐sectional study was conducted in four townships of Mandalay Region, Myanmar. From April to October 2017, bulk tank milk samples (n = 233) were collected from 233 dairy cattle farms located in Tada‐U, Pyin Oo Lwin, Meiktila, and Patheingyi Townships. From each farm, approximately 100 ml of bulk tank milk was collected and examined for bacterial content. Total bacterial count (TBC) and coliform count (CC) in milk samples were determined using milk agar and violet red bile agar. Of 233 milk samples, 68.2% (159/233) showed TBC higher than 1.0 × 105 cfu/ml, and 78.4% (183/233) showed CC higher than 100 cfu/ml. The mean value of TBC among 233 farms was 2.55 × 107 cfu/ml, ranging from 6.0 × 103 to 3.0 × 109 cfu/ml, whereas the mean value of CC was 1.59 × 105 cfu/ml, ranging from 10 to 8.4 × 106 cfu/ml. TBC tended to increase as CC increased in milk samples. The number of precautionary measures for milking operation, choice of cleaning materials, training experience of the farmers, cleanliness score of milking cows, and CMT scores of milk were significantly associated (p < 0.05) with TBC in bulk tank milk. Similarly, the number of precautionary measures for milking operation, choice of cleaning materials, training experience of the farmers, cleanliness scores of milking cows, CMT scores of milk samples, herd size, and type of milking practice showed significant association (p < 0.05) with CC in bulk tank milk. The effects of these potential risk factors should be minimized, farmers should be trained properly, and technical support should be provided, so that the quality of raw milk produced in Myanmar can be improved.

Evaluation of Antibiotic Resistance in Escherichia coli Strains Isolated from Pastry Cream in Hamadan, Iran

Background: Escherichia coli is one of the most important intestinal pathogens, which is transmitted to humans through food and has significant effects on the quality of food products, including pastry cream. Its presence in food is considered an indicator of fecal contamination. Objectives: This study aimed to determine the prevalence and pattern of antibiotic resistance of Escherichia coli in pastry cream prepared in Hamadan, Iran. Methods: The pastry cream samples (n, 350) were randomly purchased from confectionery suppliers, located in different districts of Hamadan. Forty-seven out of 350 samples contained E. coli. The bacteria were identified after culturing the samples in a nutrient-broth-enriched medium and solid media, such as violet red bile agar (VRBA), eosin methylene blue (EMB), and nutrient agar (NA), to identify bacteria isolated by the linear method. The samples were then incubated at 37°C for 24 to 48 hours. Results: The results of antibiotic tests showed the highest resistance to tetracycline, vancomycin, oxacillin (100%), and penicillin (72.34%) and the highest sensitivity to chloramphenicol (78.23%), ciprofloxacin (76.59%), and nalidixic acid (61.70%). Conclusions: According to the present findings and similar research from Iran, the rate of E. coli resistance to antibiotics is high. To avoid the contamination of pastry cream by these bacteria, some techniques, including cold chain management, employee personal hygiene, use of healthy raw materials, and proper thermal processes, should be adopted.

Occupational exposure to bioburden in Portuguese bakeries: an approach to sampling viable microbial load.

In bakeries, a number of operations such as mixing are associated with exposure to air-suspended flour dust and related bioburden. The aim of this study was to find the best active sampling approach to the assessment of occupational exposure to bioburden in Portuguese bakeries based on the data obtained with the use of specific impaction and impinger devices. We used impaction to collect fungal particles from 100 L air samples onto malt extract agar (MEA) supplemented with chloramphenicol (0.05 %). For growing fungi we also used dichloran glycerol (DG18) agar-based media and for mesophilic bacteria we used tryptic soy agar (TSA) supplemented with nystatin (0.2 %). For Enterobacteriaceae we used violet red bile agar (VRBA). With impingers we also collected 300 L air samples at the 300 L/min airflow rate, inoculated onto the same culture media. The two methods, impaction and impinger, showed statistically significant differences in the following counts: fungal on MEA (z=-2.721, p=0.007), fungal on DG18 (z=-4.830, p=0.000), total bacteria (z=-5.435, p=0.000), and Gram-negative coliforms (z=-3.716, p=0.000). In all cases the impaction method detected significantly higher concentrations than the impinger method. Fungal and bacterial loads were higher in the production unit and lower in the shop. The fungal load obtained with impaction varied between 10 and 5140 CFU m-3, and total bacterial counts ranged between 10 and 4120 CFU m-3. This study has shown that the impaction method is the best active sampling approach to assessing viable bioburden in this specific occupational environment, but a multi-faceted approach to sampling and analyses combining methods and media enables a more refined risk characterisation and, consequently, better tailored risk control measures to reduce adverse health outcomes in workers.

English

Fresh and unpasteurized fruit juice is common in restaurants, cafeteria, hotels and juice house of Ethiopian cities. Most fruit juices contain sufficient nutrients that could support microbial growth. The current investigation was carried out to investigate the microbiological quality and processing conditions of fruit juice vended in Shewarobit town. Purposive sampling technique was employed to collect sixteen fruit juice samples comprising of eight avocado and eight papaya from five cafeterias and three restaurants of Shewarobit town from November 2017 to January 2018. A wide mouth sterile bottle was used to collect fruit juice. Collected samples were diluted and 0.1 mL inoculated on plate count agar to determine total viable count, on violet red bile agar to determine total coliform count, on mannitol salt agar to determine total Staphylococcal count and on Sabouraud’s dextrose agar for count of yeast and molds. Questionnaires were delivered for juice vendors to obtain information on demographic characteristics and conditions for processing. There is no significant statistical difference between numbers of microbial count (p> 0.05). The total viable count was found in the range of 1.3 × 105 to 2.9 ×105 cfu/ mL. The total coliform count was found to be between 0.1 × 105 and 2.4 × 105 cfu/mL. Staphylococci count was between 0.2 × 105 and 1.7 × 105 cfu/mL. The total yeast and mould counts for all fruit juice were in the range of 1.4 × 105 to 2.7 × 105 cfu/mL. Microbiological quality of most of the fruit juices were found to be not satisfactory when compared with Gulf region standard. Therefore, regular supervision and training about safe processing and handling is very crucial for juice vendors to improve microbiological quality of fruit juice. Key words: Fruit juice, microbial count, microbial safety.

Antimicrobial resistance of Escherichia coli found in intestinal tract of Oreochromis niloticus

Antimicrobial resistance (AMR) is an emerging public health problem worldwide. Agricultural practices have been suggested as one of the main contributors to the emergence and transmission of AMR worldwide. Aquatic animals like fish have an important role to play in the emergence and transmission of AMR strains. Escherichia coli is commensal in gastrointestinal tracts of many animals including fish, and is an indicator organism and opportunistic pathogen. It has been listed as one of the important bacteria involved in the emergence and spread of antimicrobial resistance factors. The objective of this study was to investigate the AMR patterns of E. coli isolated from the intestinal tract of fish within the Lake Victoria basin. A total of 60 Oreochromis niloticus fish were sampled from cages, wild and earthen ponds. Distal gastrointestinal tract was recovered, crushed and streaked on violet red bile agar, incubated at 37 OC for 24 hours. The isolates confirmed biochemically as E. coli were screened for antibiotic susceptibility against 10 commonly used antibiotics using disc diffusion method. Eighty three percent of the sampled fish were positive for E. coli. Generally, isolates were susceptible to ciprofloxacin, gentamicin, cephalexin, ceftriaxone and nitrofurantoin (100%); tetracycline, sulfamethoxazole-trimethoprim (81.8%) and nalidixic acid (72.7%). However, most of them were resistant to ampicillin and erythromycin (72.7%). The results show that fish are reservoirs of E. coli, which is resistant to some antibiotics. The factors responsible for the observed resistance patterns need to be followed up with more research. Good aquaculture practices, surveillance and monitoring of resistant bacteria will help in understanding the problem of AMR.Key words: Antibiotics, antimicrobial resistance, Escherichia coli, fish

Effectiveness of a wool based packaging system on the abundance of surface spoilage microorganisms on fresh meat

The present study assessed the microbiological quality of meat packaged and stored at room temperature for 40 h in conventional EPS (expanded polystyrene) boxes and cardboard boxes lined with wool using standard, approved culturing techniques. Swabs were taken from a number of areas within the boxes, including the surface of the boxes (at the top, middle and bottom), within the Woolcool® felt fibres, and from condensed liquid found on the surface of meat packs. A lamb breast joint from each box was sampled directly. Plate Count Agar, violet red bile agar, malt extra agar and brilliance E. coli/coliform agar were used to assay bacteria numbers found on the different surfaces. The findings suggest that the wool may have potential market value as packaging liners for transporting meat, and possibly other food products. Further research is needed to allow better characterisation to real-world conditions, and understanding of how wool used as a packaging liner could help maintain food quality on a larger scale.

SCREENING OF COMMERCIAL ENRICHMENT MEDIUM FOR SELECTIVE GROWTH OF E. COLI

Different selective enrichment media like Violet Red Bile agar (VRBA), Eosin Methylene Blue (EMB), Tergitol-7 (T-7), Difco MI broth and MacConkey Broth were evaluated for recovery of different strains of E. coli (25922, 11229 and 14948) with the other organisms of the enterobacteriaceae family when spiked in broth as well as in milk. The efficacy of T-7 medium was determined as a better enrichment medium for growth of pathogenic/non-pathogenic E. coli over medium like Violet Red Bile Broth (VRBB), Eosin Methylene Blue (EMB) and MacConkey Broth as compared with the growth of other organisms like S. abony NCTC 6017 , S. flexneri ATCC 12022 , Y. enterocolitica ATCC 23715 and S. marcescens 13880. E. coli was used as indicator organism and other organisms were treated as background microflora (contaminants) and growth pattern study were conducted by enumerating cell count after every 6.0 h of interval on their respective selective media. Growth pattern study reveals that T-7 broth could inhibit the background microflora to a more extent and simultaneously showed good recovery of target organism i.e. E. coli . The selective agents already present in the T-7 broth could be optimized and some new selective agents should be tried for better recovery regarding pathogenic/non-pathogenic E. coli and more inhibition towards background microflora.

&lt;span lang="EN-GB" style="font-size: 12.0pt; font-family: Times New Roman"&gt; The Survey of Microbial Quality of the Dry Sample, Extract and Brewing of some Medicinal Plants &lt;/span&gt;&lt;/p&gt;

Medicinal plants may be exposed to a wide range of microbial contamination during pre- and post- harvest stages and they can present high microbial counts. In this study, the microbial quality of 44 samples of dry herbs namely: mint (Menthaspp.), lemon balm (Melissa officinalis), summer savory (Satureja hortensis), zataria (Zataria multiflora), Indian valerian (Valeriana wallichii), their brewing and extracts were analyzed. Total count using plate count agar medium (PCA), coliform count by Violet Red Bile Agar (VRBL), Enterobacteriacea by Violet Red Bile Glucose (VRBG) were evaluated. Medium Baird-Parker agar (BP) medium and Tryptone Bile X-Gluc (TBX) medium were used for the isolation and enumeration of Staphylococcus aurous and E. coli spp. respectively. Furthermore, Xylose Lysine Deoxycholate agar medium (XLD) and Bismuth Sulfite Agar medium(BSA) were used for detection of Salmonella spp. Fungal and mold contamination was assessed using yeast extract glucose chloramphenicol agar. The results showed that the contamination of the samples with total count (100%) and Enterobacteriaceae (85%), total coliform (83%), mold and yeast (98%) and E. coli ssp. (2.27) were detected, including in the study samples the absence of pathogenic bacteria like Staphylococcus aurous, Salmonella spp. Moreover, the extract had a lower microbial load in comparison to dry herb samples. Also, the lowest and the highest of contamination rates were observed for Indian valerian and zataria, respectively. According to the results, there is a need to control the environmental conditions and improve hygiene in the production process; even more, it is recommended to choose a suitable decontamination method for disinfection during packing medicinal plants and during post-packing manipulation and transport.

&lt;span lang="EN-GB" style="font-size: 12.0pt; font-family: Times New Roman"&gt; The Survey of Microbial Quality of the Dry Sample, Extract and Brewing of some Medicinal Plants &lt;/span&gt;&lt;/p&gt;

Medicinal plants may be exposed to a wide range of microbial contamination during pre- and post- harvest stages and they can present high microbial counts. In this study, the microbial quality of 44 samples of dry herbs namely: mint (Menthaspp.), lemon balm (Melissa officinalis), summer savory (Satureja hortensis), zataria (Zataria multiflora), Indian valerian (Valeriana wallichii), their brewing and extracts were analyzed. Total count using plate count agar medium (PCA), coliform count by Violet Red Bile Agar (VRBL), Enterobacteriacea by Violet Red Bile Glucose (VRBG) were evaluated. Medium Baird-Parker agar (BP) medium and Tryptone Bile X-Gluc (TBX) medium were used for the isolation and enumeration of Staphylococcus aurous and E. coli spp. respectively. Furthermore, Xylose Lysine Deoxycholate agar medium (XLD) and Bismuth Sulfite Agar medium (BSA) were used for detection of Salmonella spp. Fungal and mold contamination was assessed using yeast extract glucose chloramphenicol agar. The results showed that the contamination of the samples with total count (100%) and Enterobacteriaceae (85%), total coliform (83%), mold and yeast (98%) and E. coli ssp. (2.27) were detected, including in the study samples the absence of pathogenic bacteria like Staphylococcus aurous, Salmonella spp. Moreover, the extract had a lower microbial load in comparison to dry herb samples. Also, the lowest and the highest of contamination rates were observed for Indian valerian and zataria, respectively. According to the results, there is a need to control the environmental conditions and improve hygiene in the production process; even more, it is recommended to choose a suitable decontamination method for disinfection during packing medicinal plants and during post-packing manipulation and transport.

The Possibility of Using Fibers as a Prebiotic in Making of Probiotic Based On-Some Dairy Products

Probiotic microorganisms were found to affect the host health beneficially when found in an a certain count not less than 106 CFU/g (Colony-forming unit / gram), and they have some benefits as protection from cancer, relief of lactose intolerance, reduce the risk from diarrhea, normalize the bowel movement, and enhance the immune functions, reduce cholesterol level and reduce the risk of eczema. This study was carried out to examine some of fibers and polysaccharide for their assimilation by some lactic acid bacterial strain specially known for their probiotic effect. It was concluded from the present study the following: studying the capability of Esherichia coli (E. coli), bifidobacteria and 9 strains related to lactic acid bacteria included in assimilating 7 different (polysaccharides, fibers and other materials) included (Polydextrose, Maltodextrine, inulin, prolia, resistant starch, wheat fiber and gumarabic) when substituted with dextrose inde Man, Rogosa and Sharpe (MRS) broth and incubated at their optimal temperature. The results revealed that the examined culture were varied in their assimilation of the 2% polysaccharides tested, furthermore maltodextrin, showed a good assimilation by Bifidobacterium longum ATCC 15707 (B. longum) and Lactobacillus acidophilus NRRLB1910 (L. acidophilus). The effect of certain concentrations (2, 3and 4%) of the selected (polysaccharides, fibers and other materials) on the growth activity of the lactic acid bacterial cultures tested in addition to E. coli (as a representative for coliform bacteria). The results revealed that upon increasing Original Research Article British Microbiology Research Journal, 4(6): 678-697, 2014 679 the concentration of the selected polysaccharides there was a remarkable decrease in pH compared to E. coli which showed contrast outcomes on which its pH were significantly higher than the tested bifidobacteria and lactic acid bacteria. Studying the effect of incubation duration and it’s relation on the selected (polysaccharides, fibers and other materials) assimilation by the tested lactic acid bacterial cultures. Results revealed that there is a direct proportion relation between long incubation timing and polysaccharide assimilation (indicated by decrease in pH). This decrease was very clear at 24 hours of incubation at the optimum temperature for each strain. Upon studying the antagonistic effect between E. coli with B. longum ATCC 15707, L. acidophilus NRRLB 1910 and Lactobacillus reuteri B 14171 (L. reuteri) grown on modified MRS with 3% of each polysaccharide (polydextrose, maltodextrin and inulin). The change in the growth of these cultures combinations were determined by counting on MRS and Violet red bile agar (VRBA). It was shown that these (polysaccharides/fibers) challenged the growth of the probiotic bacteria and the count of E. coli (wild) E.W was lowered significantly due to the inhabitation effect of the used probiotic bacteria. It was concluded that good results was shown from using the three polysaccharides/fibers (maltodextrin, inulin andpolydextrose) that was elected to base the rest of work on.