Number Of Bacterial Populations Research Articles

Supplementation of date palm (Phoenix dactylifera L.) residue for growth and lactic acid production of probiotic bacterial Lactobacillus spp.

Date palm is an age-old cultivated plant that thrives in tropical and subtropical regions. The date palm is a bountiful source of carbohydrates, encompassing sucrose, glucose, and fructose and proteins. The date industry generates a significant volume of unused by-products. Dates offer a diverse range of by-products beyond the agri-food sector. LAB have garnered extensive utilisation across diverse food sectors, spanning meat, vegetables, beverages, dairy products, and other fermented foods. In the quest for establishing a new large-scale fermentation process for lactic acid there has been a concerted effort to utilise more cost-effective medium components. In the present work, date palm residue (DPR) derived from date palm fruit, after sugar extraction, was incorporated into MRS. The fermentation process was executed through two distinct fermentation systems. Initially, experiments were conducted in flasks. Afterward, the optimal conditions for bacterial growth were determined, and the experiment was carried out using a bioreactor. DPR supported the probiotic Lactobacillus spp. growth especially after 48 h incubation. The prebiotic effect of DPR on Lactobacillus spp. was reported. An increase in the total number of bacterial populations was observed in response to the addition the DPR until 48 h. Specifically, the supplementing DPR at a concentration of 1.5% in batch fermentation enhanced the growth and lactic acid production of Lactobacillus casei. This study suggests that DPR could potentially function as an economical prebiotic source and could be seamlessly incorporated as a functional food ingredient, thereby transforming a waste product into an economically sustainable food substrate.

PREVALENCE OF ESCHERICHIA COLI, COLIFORM AND NON-COLIFORM BACTERIA IN MUD BUFFALO IN RANGGAGATA AND SERAGE VILLAGES, SOUTHWEST PRAYA SUBDISTRICT, DISTRICT OF CENTRAL LOMBOK, WEST NUSA TENGGARA

Escherichia coli (E. coli) is a common bacterium that inhabits the intestines of humans and animals with hundreds of different strains, both harmful and harmless. One of the diseases that can be caused by E. coli is diarrhea. Diarrhea is a disease in the form of increased frequency of defecation, thinner stool consistency and increased intestinal peristalsis. This study aims to determine the number of E. coli, coliform and non-coliform bacteria in mud buffaloes in Ranggagata and Serage Villages, Southwest Praya Subdistrict, Central Lombok Regency, West Nusa Tenggara with samples used are fresh feces samples, a total of 14 samples. Sample cultivation was carried out on Eosin methyleneblue agar (EMBA) media then samples suspected of E. coli colonies were Gram stained, and biochemical tests on Triple Sugar Iron Agar (TSIA) media, Sulfide Indole Motility (SIM), Methyl red-Voges Proskauer (MR-VP) media, Simmons Citrate and catalase tests. The results showed the number of bacterial populations varied depending on the age of the buffalo with an average number of E. coli bacteria 162.143 ± 196.476, average coliform 272.000± 328.307 and average non-coliform 110.714 ± 201.855. Based on the results of the study it can be concluded that there is an increase in the number of E. coli, coliform and non-coliform as the age of buffalo increases, namely for E. coli is Y = 2.527+0.009x, coliform is Y = 2.525+0.05x and non-coliform bacteria is Y = 3.199+0.007x. Further tests need to be conducted related to other strains or species of E. coli, coliform and non-coliform bacteria in mud buffalo feces.

Keragaman dan Resistensi Antibiotik Isolat Bakteri Tanah di Dalam dan Luar TPU Bonoloyo, Surakarta Jawa Tengah

A cemetery acts as an active decomposition site and contains bacteria which most likely have antibiotic resistance. However, related data to the phenomenon is limited. This study aimed to compare the diversity of bacteria inside and outside the cemetery and examine bacterial antibiotic resistance. First, samples were collected from three different spots inside and outside the Bonoloyo public cemetery in Surakarta, Central Java. Then, the bacteria were isolated by spread plate method on NA medium and were observed using Gram staining after 48 hours of incubation. Also, bacterial resistance against cefepime, bacitracine, and ampicilin were examined. As the results, bacterial populations inside and outside the cemetery area are 3.4x106 and 4.6x106 CFU/gram, respectively, with a diversity of 38% and 34%, while 28% of isolates are collected from both areas. The result of morphological observation showed that 15 and 21 isolates are respectively round and irregular, white to yellow colour with raised (16 isolates) and flat (19 isolates) elevation. Gram staining showed 48 isolates are coccus and 2 are bacilli, with 23 isolates of Gram negative and 27 isolates of Gram positive. Bacterial isolates showed resistance against cefepime (50%-50%) and against bacitracine (52%-43%) each from both areas of the cemetery, while resistance against ampicilin was relatively low (33%-21%). The number of bacterial populations and bacterial diversity inside and outside the cemetery area are not significantly different. In fact, the resistance of the soil bacteria population collected from cemetery soil are higher than that collected from soil outside the cemetery.

Soil Bacterial Community Structure and Function under the Substitution of Chemical Fertilizer with Maize Straw

The long-term extensive application of chemical fertilizers wreaks havoc on soil bacterial structure and function. To reduce the damage caused by chemical fertilizers, a six-year experiment was performed to study the effects of replacing 0% (CK), 25% (S25), 50% (S50), 75% (S75), and 100% (S100) of 225 kg ha−1 mineral nitrogen fertilizer with an equivalent amount of nitrogen from maize straw on the soil bacterial community structure, diversity, and function. The results showed that Proteobacteria, Acidobacteria, and Gemmatimonadetes were the dominant soil bacterial phyla after the replacement treatments. Replacing mineral nitrogen fertilizer with an equivalent amount of nitrogen from maize straw significantly reduced the number of Photobacterium and bacterial populations involved in genetic information processing in soil, but significantly increased the number of bacterial populations involved in organismal systems, human diseases, and environmental information processing. Compared with other treatments, the relative abundance of TK10 significantly increased by 33.52–76.36% in S25. The number of subgroup 6, Gram-negative, biofilm-forming, potentially pathogenic, and anaerobic bacteria significantly increased, whereas that of Chloroflexi and Blastocatellia subgroup 4 significantly decreased in S50 and S75 compared with CK. The number of TK10 and Blastocatellia subgroup 4 in S50 and S100, respectively, was significantly lower than that in CK. Bacterial species were significantly more present in S25 than in S75. The diversity of bacterial species in S75 was significantly lower than that in CK. S25 and S100 were more favorable to increasing the number of Gram-positive, aerobic, mobile-element containing, and stress-tolerant bacteria. Rhodobacteraceae, Pyrinomonadaceae, Xanthobacteraceae, Nocardioidaceae, and Vulgatibacteraceae with statistical differences in CK, S25, S50, S75, and S100, respectively, could be used as biomarkers. Chloroflexi, Acidobacteria, and Nitrospirae could be used as the main basis for the bacterial classification of soil samples in the equivalent substitution of nitrogen chemical fertilizer with maize straw. S25 is ideal for increasing soil bacterial species richness and abundance.

Viability Test of Hydrocarbonoclastic Bacteria Consortium Entrapted on Sawdust Material

Oil spills in the sea are generally prevented in various ways, one of them is the bioaugmentation method through bacterial entrapment on sawdust carriers. The entrapment of bacteria is one of the bacterial immobilization techniques. The potential of bacterial consortium on sawdust is still not widely used, especially in long-term storage. The purpose of this study was to obtain the viability of hydrocarbonoclastic bacterial consortium on sawdust after 0, 7, and 41 days of storage. The bacterial consortium consists of Bacillus aquimaris, B. megaterium, B. pumilus, Halobacillus trueperi, and Rhodobacteraceae bacterium. The samples were tested by culturing the immobilized bacterial consortium of 0, 7, and 41 days on falcon tubes containing crude oil and seawater. The viability of the immobilized bacterial consortium was tested for 28 days (days 0, 7, 14, 21, and 28) by enriched the bacterial populations periodically. The viability test was also supported by the measurement of environmental parameters on the 1 st day and the 28 th day such as DO, pH, salinity and, temperature. The results show that bacterial consortium in all storage periods was viable on sawdust carriers which related to the high number of bacterial populations on the 28 th day. The most viable bacterial consortium on sawdust was the 0-day storage (9.59 x 10 8 CFU/ml) which was indicated by the increases phase at the end of the day. It was proved that the bacteria are still productive and could degrade petroleum hydrocarbons.

Assessment of silver release and biocidal capacity from silver nanocomposite food packaging materials

In this study, silver release from commercially available food-contact materials in food simulants (water, acetic acid, ethanol-water and olive oil) and meats (tuna, ham, and turkey) was assessed. Additionally, the antimicrobial capacity of migrated silver was examined in meats. Largest silver release was observed in simulants from food touch papers (25 ± 11 mg/kg) as compared to bag, cutting board and containers. Silver ion and silver nanoparticles were released from food touch paper in food simulants. Food touch paper released the highest amount of silver in tuna (0.5 ± 0.02 mg/kg) than ham (0.2 ± 0.08 mg/kg) or turkey (0.3 ± 0.08 mg/kg) in the same conditions. Tuna exhibited the lowest pH and higher number of bacterial populations on day 0 compared with other foods. Nonetheless, a significant antibacterial capacity of released silver was noticed predominantly in turkey for Gram-negative bacteria.Our study suggests silver released in food simulants indicate an overestimation of silver migration; thus, precaution should be maintained when extrapolating such findings to “real” food. Moreover, further investigations are needed to determine if the amount of silver released from food touch paper in certain foods (for example turkey in the present study) possess any risk to human health.

Use of Probiotics to Fight Bacterial Populations of Vibrio sp. on Vaname Shrimp Cultivation (Litopenaeus vannamei)

The consequence of super intensive shrimp farming is an increase in aquaculture waste and disease transmission. Vibrio sp. Bacteria is a disease-causing agent in shrimp larvae when the shrimp is in a state of stress and weakness, and can cause death. The application of probiotics, namely beneficial microorganisms can degrade organic matter, reduce disease, and help accelerate the process of nutrient cycles as a consequence of super intensive shrimp farming. Commercial probiotics currently available are a mixture of several types of beneficial microorganisms, namely Bacillus sp., Pseudomonas sp., Nitrosomonas sp., Aerobacter sp., and Nitrobacter sp. The purpose of this study was to evaluate the use of probiotics with different time intervals to produce a decrease in the population of Vibrio sp. The research method applied was the treatment of commercial probiotics at different intervals of three, five, and seven days and without the administration of probiotics as controls. Furthermore, the bacterial population was calculated by total plate count (TPC). The results showed that the administration of probiotics had a significant effect on the decrease in the population of Vibrio sp. Provision of probiotics three days apart showed a decrease in the number of bacterial populations that were significantly different from the controls, but the same as the administration of intervals of five and seven days. The decrease in the number of bacterial populations in the treatment interval of three, five, and seven days in a row is 0.05 x , 0.41 x , and 0.61 x CFU / ml. This study recommends that the use of commercial probiotics intervals of seven days for super intensive vaname shrimp farming. The use of probiotics for three days indicates an impact on the increase in expenditure costs for probiotics. Commercial probiotic studies modified with natural microorganisms are thought to be able to streamline the operational costs of shrimp farming.Keywords: Vibrio sp. bacteria, probiotics, vaname shrimp, super intensive cultivation

EFFECT OF PRE HARVEST APPLICATION OF BIOFORMULATIONS ON THE ANTHRACNOSE DISEASE INCIDENCE AND BIOMETRICS OF MANGO

ABSTRACT The effect of pre harvest application of bioformulations on the disease incidence of leaves, inflorescence, fruits and biometrics of mango was tested in this study. Foliar spraying of Pseudomonas fluorescens (BIB2) + Bacillus subtilis (BIL8) + chitin on 20 days before flowering, flowering stage, 20 and 60 days after flowering plus Carbendazim (0.1%) at 40 days after flowering recorded the minimum incidence of leaf anthracnose at pre flowering, flowering, fruit set and fruit maturity stages viz., 8.67, 12.33, 13.00 and 13.00 per cent, respectively. Similarly nil infection on inflorescence and fruit was recorded in above treatment. The same treatment recorded maximum number of panicle/tree (142.00), fruits/tree (748.67), fruit weight (221.76g/fruit) and fruit yield/tree (166.02 kg). P. fluorescens (BIB2) + B. subtilis (BIL8) + chitin recorded highest number of bacterial population (16.67 ×104 cfu g-1 of leaf) at 16 days after spray.

COUNTING TOTAL BACTERIA IN LAND ORGANIC WASTE HOUSEHOLD AND LAND INORGANIC WITH TOTAL PLATE COUNT METHOD (TPC)

The soil fertility aspect is characterized by the good biological properties of the soil. One important element of the soil biological properties is the bacterial population present in it. This research was conducted in the laboratory of Microbiology University of Malikussaleh in the May until June 2016. This study aims to determine the number of bacterial populations in soil organic and inorganic so that can be used as an indicator to know the level of soil fertility. Data analysis was done by T-Test that is by comparing the mean of observation parameter to each soil sample. The sampling method used is a composite method, which combines 9 of soil samples taken from 9 sample points on the same plot diagonally both on organic soil and inorganic soil. The results showed the highest bacterial population was found in total organic soil cfu 180500000 and total inorganic soil cfu 62.500.000

ENUMERASI DAN ANALISIS BAKTERI TANAH DI HUTAN LARANGAN ADAT RUMBIO (Enumeration And Bacteria Analysis of Soil on The Larangan Adat Rumbio Forest)

One of indicator of soil fertility is the population level of microbial in the soil. This research aims to determine the number of bacterial populations in the soil on yhe Larangan Adat Rumbi Forest with different levels of depth. This research has been carried out on January-February 2015 in the Laboratory of Pathology, Entomology and Microbiology, Faculty of Agriculture and Animal Sciences of State Islamic University of Sultan Syarif Kasim Riau. The method that was used namely observation method by taking soil samples on the Larangan Adat Rumbio Forest then calculated the number of colonies of bacteria and analyze the morphology of the bacteria that was obtained macroscopically and microscopically. Parameters measured were pH of soil, the population of bacteria, bacterial morphology, gram stain, and bacterial cell shape based on soil depth of 0-10 cm, 11-20 cm, 21-30 cm. Observations carried out two stages macroscopic and microscopic observation. The results showed the soil pH on the Larangan Adat Rumbio Forest was 4,11. Total population of bacteria at depth of 0-10 cm namely 3,0 x 109 CFU, then at a depth of 11-20 cm namely of 2,2 x 109 CFU and at depth of 21-30 cm namely 1,6 x 108 CFU. The Results of purification of culture was obtained six isolat two coccus and four bacil consisting of five gram negative bacteria and one gram positive. Need to do further research on bacteria identification to genus or species level.

Uji Biologis Konsumsi Pakan, Populasi Bakteri Rumen dan pH Pellet Complete Calf Starter pada Pedet Friesian Holstein Pra Sapih

(Biological test feed intake, population rumen bacteria and ph pellet complete calf starter friesian holstein on pre weaning calf) ABSTRACT. The study aims to assess the quality of the formula Complete Calf Starter (CCS) with 5% molasses instead of milk to the development of rumen microbial calf Holstein Friesian (HF) pre-weaning. The material used is 20 head calf FH pre weaning age of 2 weeks. Feed intake data taken from 20 respondents consisted of 16 females and 4 calf tail male calf. Data rumen bacterial populations and pH were taken from 5 head of cattle slaughtered at the age of 2 weeks (one tail), 4 weeks (2-tailed) and 6 weeks (2-tailed). The study was designed as a descriptive non-parametric. Parameters measured were rumen bacterial populations, pH and feed intake. The results showed the average consumption of dry matter (DM) and CCS calf milk FH ages 2, 4, 6 weeks respectively at 506, 517, 528 grams. Rumen bacterial populations in calves aged 2, 4, and 6 weeks of 80x106, 45x106 and 19x106 kol/m. ruminal pH in calves aged 2, 4 and 6 weeks was 5.71, 5.36 and 5.55. Biological test showed that the use of complete calf starter (CCS) in the form of pellets FH calves at the age of 2 weeks to stimulate the development of the rumen (feed intake, the population of bacteria and pH) but not in calves aged 4 and 6 weeks. This is because the number of bacterial populations declined due to impaired absorption is impaired absorption of VFA marked low rumen pH.

The Utilization of Natural Reservoir Brine in an Enrichment Culture Medium: An Alternative Approach for Isolation of Anaerobic Bacteria from an Oil Reservoir

This study aims to suggest the new approaches of enrichment cultures using natural reservoir brine for enrichment culture medium in order to increase the bacterial population in the enrichment cultures and isolate novel thermophilic anaerobic bacteria from an oil reservoir. The results suggest that the brine-based culture medium should be sterilized by filtration to increase the number of bacterial population and CO2 should be supplied to culture medium to increase the possibility of isolating novel bacteria from oil reservoirs. One of the specific bacteria isolated under the presence of CO2 was a strain AR80 representing a novel bacterium within the genus Petrotoga on the basis of the phylogenetic analysis.

Isolation and Identification of Uterine Microorganisms in Postpartum Dairy Cows

The aim of this study was to isolate and identify uterine microorganisms in postpartum cows and to observe the occurrence of uterine infection in crossbred and local cows. One hundred and nine samples, from both crossbred and local dairy cows were collected from Chittagong area. They were inseminated artificially (n=89) and naturally (n=20). Samples were collected at least 3 months after calving. Among the selected cows, 33 had different reproductive diseases and the rest were from apparently healthy cows. The crossbred dairy cows were more susceptible to reproductive diseases (19.27%) than the local ones. Uterine infection was higher (52%) in cows inseminated artificially than that of natural ones (21.21%). Nineteen different types of bacteria were isolated from both diseased and healthy animals, except Clostridium spp and Nocardia spp which were not found in diseased animal. Likewise, Bacillus spp and Salmonella spp were absent in healthy animals. Most prevalent bacteria in diseased animal were Staphylococcus spp and Streptococcus spp found in 33% and 27.3% of the cases respectively. In non-diseased cases, the highest number of samples was positive for Bacteroied spp (13.2%) followed by Streptococcus spp (10.4%). On average, the highest number of bacterial population was isolated from diseased samples and most of those bacteria are pathogenic. DOI: http://dx.doi.org/10.3329/bjm.v28i1.11804 Bangladesh J Microbiol, Volume 28, Number 1, June 2011, pp 19-23

The type and quantity of dietary fat and carbohydrate alter faecal microbiome and short-chain fatty acid excretion in a metabolic syndrome ‘at-risk’ population

An obese-type human microbiota with an increased Firmicutes:Bacteroidetes ratio has been described that may link the gut microbiome with obesity and metabolic syndrome (MetS) development. Dietary fat and carbohydrate are modifiable risk factors that may impact on MetS by altering the human microbiome composition. We determined the effect of the amount and type of dietary fat and carbohydrate on faecal bacteria and short chain fatty acid (SCFA) concentrations in people 'at risk' of MetS. A total of 88 subjects at increased MetS risk were fed a high saturated fat diet (HS) for 4 weeks (baseline), then randomised onto one of the five experimental diets for 24 weeks: HS; high monounsaturated fat (MUFA)/high glycemic index (GI) (HM/HGI); high MUFA/low GI (HM/LGI); high carbohydrate (CHO)/high GI (HC/HGI); and high CHO/low GI (HC/LGI). Dietary intakes, MetS biomarkers, faecal bacteriology and SCFA concentrations were monitored. High MUFA diets did not affect individual bacterial population numbers but reduced total bacteria and plasma total and LDL-cholesterol. The low fat, HC diets increased faecal Bifidobacterium (P=0.005, for HC/HGI; P=0.052, for HC/LGI) and reduced fasting glucose and cholesterol compared to baseline. HC/HGI also increased faecal Bacteroides (P=0.038), whereas HC/LGI and HS increased Faecalibacterium prausnitzii (P=0.022 for HC/HGI and P=0.018, for HS). Importantly, changes in faecal Bacteroides numbers correlated inversely with body weight (r=-0.64). A total bacteria reduction was observed for high fat diets HM/HGI and HM/LGI (P=0.023 and P=0.005, respectively) and HS increased faecal SCFA concentrations (P<0.01). This study provides new evidence from a large-scale dietary intervention study that HC diets, irrespective of GI, can modulate human faecal saccharolytic bacteria, including bacteroides and bifidobacteria. Conversely, high fat diets reduced bacterial numbers, and in the HS diet, increased excretion of SCFA, which may suggest a compensatory mechanism to eliminate excess dietary energy.

Soybean Response to 1-Aminocyclopropane-1-Carboxylate Deaminase-Producing &lt;i&gt;Pseudomonas&lt;/i&gt; under Field Soil Conditions

Problem Statement: 1-Aminocyclopropane-1-Carboxylate (ACC) deaminase-producing bacteria have been known to promote plant growth by decreasing ethylene inhibition of various plant processes. However, their efficacy under field soil conditions may vary depending on the range and variability of the environmental factors. This study examined the ability of eight promising isolates of ACC deaminase-producing Pseudomonas to enhance soybean growth under acidic and low fertility status of field soil conditions. Approach: The bacteria were formulated into peat-based carrier and used to inoculate soybean seeds. Cell viability in the carrier was evaluated periodically. The number of bacterial population at the time of seed inoculation was above 107 cell g-1. Treated and untreated seeds were grown in plots (5×4 m2) and set in a randomized complete block design with 3 replicates. Observations were made at 30 d after planting for shoot height and weight, number of nodules and at harvesting for number of pods and yield. Results: Three out of eight isolates significantly increased soybean growth exhibited by higher number of nodules and pod filling and higher seed dry weight than those of untreated control. Those five remaining bacteria, on the contrary, inhibited soybean growth indicating that other unknown external factors influenced or covered the beneficial trait of ACC deaminase. Conclusion: Bacteria having ACC deaminase activities could be truly plant growth promoting bacteria providing that their beneficial effects are consistent at a wide range of environmental conditions.

Zeta-Proteobacteria Dominate the Colonization and Formation of Microbial Mats in Low-Temperature Hydrothermal Vents at Loihi Seamount, Hawaii

In situ colonization experiments were performed to study the pioneer populations of bacteria at Loihi Seamount, Hawaii. Over a ten-year sampling period, 41 microbial growth chambers (MGCs) were deployed and recovered in Pele's Pit and the surrounding area after short-term (4–10 days) and long-term (∼1–6 years) incubations in the flow of hydrothermal effluent. Terminal-restriction fragment length polymorphism (T-RFLP) analysis of the small subunit rRNA gene (SSU rDNA) revealed that the short-term MGC communities exhibited a low number of represented populations when compared to the long-term MGC communities and naturally occurring microbial mats. Cluster analysis of T-RFLP fingerprints showed the short-term MGC communities all had similar richness but were separated into three distinct groups with different arrays of colonizing populations. Clone library analysis showed that cooler vents (T ave = 40°C) were primarily colonized by Mariprofundus ferrooxydans, a neutrophilic Fe-oxidizing ζ −Proteobacteria while warmer vents (T ave = 71°C) were colonized by Sulfurimonas spp. and other sulfur-cycling members of the ϵ −Proteobacteria. Vents with an intermediate temperature (T ave = 51°C) were colonized by representatives of both ζ -Proteobacteria and ϵ -Proteobacteria. Long-term MGC communities did not cluster with any of the short-term communities and exhibited higher richness, indicating a greater number of bacterial populations were able to colonize and grow in the long-term growth chambers.

Some aspects of forest soil and litter ecology in the Dawyck Cryptogamic Sanctuary with a particular reference to fungi

Here we report on ecology and biodiversity of fungi in a unique mycological sanctuary in Britain, where data on species composition have been collected since 1994. To complement the biodiversity data by the information on the fungal ecological interactions and their role in the overall ecosystem functioning, soil properties and the composition of forest litter and field layer, bacterial population numbers and fungal biomass (in terms of ergosterol) were measured in 8 plots covered with different vegetations (beech, birch, birch-oak-beech, grass) over a May–Aug. period, and the results were analysed by correlation analysis and stepwise regression modelling together with data on protozoa and nematodes available from parallel research. The results highlighted the complexity of factors influencing temporal dynamics and spatial variability of fungal biomass in soil and forest litter. Most of the registered interactions appeared to be transient, and this should be taken into account while interpreting environmental observations. Interpretation of the specific relationships is given and implications for further research and overall ecosystem functioning are discussed.

Influence of Transgenic Corn on the In vitro Rumen Microbial Fermentation

In this study, the comparative effects of transgenic corn (Mon 810 and Event 176) and isogenic corn (DK729) were investigated for their influence on in vitro rumen fermentation. This study consisted of three treatments with 0.25 g rice straw. 0.25 g of corn (Mon810/Eventl76/DK 729) mixed with 30 ml rumen fluid-basal medium in a serum bottle. They were prepared in oxygen free conditions and incubated at 39°C in a shaking incubator. The influence of transgenic corn on the number of bacterial population, F. succinogenes (cellulolytic) and S. bovis (amylolytic), was quantified using RT-PCR. Fermentative parameters were measured at 0, 2, 4, 8, 12 and 24 h and substrate digestibility was measured at 12 and 24 h. No significant differences were observed in digestibility of dry matter, NDF, ADF at 12 and 24 h for both transgenic and isogenic form of corns (p>0.05) as well as in fermentative parameters. Fluid pH remained unaffected by hybrid trait and decreased with VFA accumulation as incubation time progressed. No influence of corn trait itself was seen on concentration of total VFA, acetic, propionic, butyric and valeric acids. There were no significant differences (p<0.05) in total gas production, composition of gas (methane and hydrogen) at all times of sampling, as well as in NH 3 -N production. Bacterial quantification using RT-PCR showed that the population number was not affected by transgenic corn. From this study it is concluded that transgenic corn (Mon810 and Event 176) had no adverse effects on rumen fermentation and digestibility compared to isogenic corn. However, regular monitoring of these transgenic feeds is needed by present day researchers to enable consumers with the option to select their preferred food source for animal or human consumption.

Fungal and bacterial enzyme activities in Alnus nepalensis D. Don

Fungal and bacterial numbers and their enzymes activities in terms of enzymes, namely cellulase, amylase and invertase were estimated in two forest stands of alder (open and closed forest). The fungal and bacterial population numbers were higher in the closed forest than in the open ones. Consequently, the different enzyme activities were also greater in the closed forest. A correlation coefficient was calculated between fungal population numbers, bacterial population numbers, moisture content, pH, total nitrogen, weight loss, cellulose and total sugars and the enzymes activities. Invertase activity showed a positive correlation ( P < 0.05) with litter soluble sugars and total nitrogen but negatively with weight loss. Amylase and cellulase activities were correlated significantly with fungi and bacteria and moisture content of litter. Cellulase also correlated significantly but negatively with the cellulose ( P < 0.01). The results of the investigation indicated that changes in forest canopy has an effect on fungal and bacterial population numbers and microbial enzymes activities.

Bioremediation of oil sludge-contaminated soil

Bioremediation has become an important method for the restoration of oil-polluted environments by the use of indigenous or selected microbial flora. Several factors such as aeration, use of inorganic nutrients or fertilizers and the type of microbial species play a major role in the remediation of oil-contaminated sites. Experiments were undertaken for bioremediation of oil sludge-contaminated soil in the presence of a bacterial consortium, inorganic nutrients, compost and a bulking agent (wheat bran). Experiments were conducted in glass troughs for the 90-day period. Bulked soil showed more rapid degradation of oil compared to all other amendments. During the experimental period, wheat bran-amended soil showed 76% hydrocarbon removal compared to 66% in the case of inorganic nutrients-amended soil. A corresponding increase in the number of bacterial populations was also noticed. Addition of the bacterial consortium in different amendments significantly enhanced the removal of oil from the petroleum sludge from different treatment units.