C.B. Chikere

Bio: C.B. Chikere is an academic researcher. The author has contributed to research in topics: Incubation & Plate count agar. The author has an hindex of 1, co-authored 1 publications receiving 5 citations.

Effect of Growth Media and Incubation Time on the Culturability of Soil Bacteria

Abstract: The effect of growth medium and incubation time were investigated by determining the number of colonies that were visible on triplicate plates of three different media on daily intervals. The viable counts were significantly different between the three different media even after the first day and this continued for seven days. Colony counts on the three media reached their maximum on the third day of incubation. The use of Nutrient agar (NA) and Plate count agar (PCA) resulted in increasing counts with increasing incubation time respectively. Counts obtained from the Nutrient agar were higher than that of Plate count agar followed by the soil extract agar (SEA) which had the lowest count and a longer bacteria lag phase due to the low nutrient content in the soil extract agar. The Plate count agar formed more distinct colonies than the Nutrient agar and Soil extract agar. During the incubation period, colonies appeared on the Nutrient agar even on the seventh day. These characteristics of the Nutrient agar to support a higher number of colonies for a long period of time could be attributed to its nutrient composition. The colony counts upon incubation for seven days ranged from a mean of 3.0x10 5 cfu/g on Soil extract agar, 6.1x10 5 cfu/g on Plate count agar and 7.6x10 5 cfu/g on Nutrient agar for example A which was a cultivated loamy soil and 1.3x10 5 cfu/g also on Soil extract agar, 3.9x10 5 cfu/g on Plate agar and 5.6x10 5 cfu/g Nutrient agar for soil sample B which was a non-cultivated sandy soil. Longer incubation time increased colony count on the different growth media because it was so obvious on the Soil extract agar. No visible colonies were observed from the first to the third day on the Soil extract agar, visible colonies appeared on the fourth day of incubation. Also in the other growth media, there was an increase in colony count on the third day upon incubation.

The role of bacteria in the mineralization of diesel-base engine oil

Abstract: The mineralization of diesel-based engine oils produced by African Petroleum (AP) was investigated for a period of twenty-eight (28) days. Two different samples of AP engine oils, Heavy Duty Visco SAE40 (H40) and Diesel Motor Oil SAE 40 (D40) were investigated. Soil from a mechanic workshop at Irediawa Junction, along Ekenwan Road, Benin City, Edo State, Nigeria served as seed for the mineralization. The study was carried out at room temperature (27-290C). The pH of the test systems ranged from 6.5 to 7.3. The counts on the first day were 2.52x104 and 2.71 x104 for H40 and D40 respectively. Whereas the corresponding counts in 28th day were 2.04 x105 and 2.03 x105 in colony forming unit per milliliters (cfu/ml). The hydrocarbon utilizing bacteria (HUB) isolated include Alcaligene, Bacillus, Citrobacter, Micrococcus, Proteus, Pseudomonas, and Vibrio. The physicochemical analysis showed that nitrate, phosphate, sulphate, biochemical oxygen demand, (BOD), oil and grease content and total organic carbon (TOC) decreased with time. The rate mineralization between the two engine oils was in accordance with the normal growth rate for a close system. There was no significant difference between the rates of mineralization of the two engine oils.

Mineralization Of Diesel-Base Engine Oil By Fungi Isolated From Selected Workshops In Benin City, Nigeria

Abstract: The mineralization of diesel-based engine oils produced by African Petroleum (AP) was investigated for a period of twenty-eight (28) days. Two different samples of AP engine oils, Heavy Duty Visco SAE40 (H40) and Diesel Motor Oil SAE 40 (D40) were investigated. Soil from a mechanic workshop at Irediawa Junction, along Ekenwan Road, Benin City, Edo State, Nigeria served as seed for the mineralization. The study was carried out at room temperature (27-290C). The pH of the test systems ranged from 6.6 to 4.8 where the count in first day were 2.56x102 and 4.46 x105, for H40 and D40 respectively whereas the corresponding count on day 28 were 2.32 x104 and 3.85 x104 in colony forming unit per milliliters (cfu/ml). The hydrocarbon utilizing fungal isolates were identified as Aspergillus, Fusarium, Mucor, Penicillium Rhizopus, and Saccharomyces. The physicochemical analysis showed that nitrate, phosphate, sulphate, biochemical oxygen demand, (BOD), oil and grease content and total organic carbon (TOC) decreased with time. The rate mineralization between the two engine oils was in accordance with the normal growth rate for a close system. There was no significant difference between the rates of mineralization of the two engine oils.

Growth and virulence of Bacillus thuringiensis on cereals

Abstract: Five Bacillus thuringiensis isolates including two procured isolates (B. thuringiensis MTCC 868 and MTCC 4715) and three native isolates (Bt-4, Bt-10 and PAU Bt) were evaluated on different cereal based medium, their effect of incubation time, pH and various additives on the persistence of bacteria and its virulence against Spodoptera litura. Among various cereals based liquid media, wheat recorded maximum spore count (28.07×10 CFU/ ml) and was significantly better than maize, rice and sorghum. The growth parameters viz incubation time and pH were recorded and was found that maximum spore count (27.87×10 CFU/ ml) was recorded after 72 hours of incubation which was at par with 96 and 120 hours. The maximum spore count (27.73×10 CFU/ ml) was recorded at pH 7.5 and was at par with spore count (25.60×10 CFU/ ml) at pH 7.2. Influence of different additives viz carboxymethyl cellulose, triton x 100, boric acid, methyl-p-hydroxybenzoate and glycerol on the persistence of B. thuringiensis isolates was studied. It was found that the spore count varied with the different concentrations of additives. The maximum spore count 26.33×10, 24.80×10, 23.93×10, 23.20×10 and 20.53×10 CFU/ ml were recorded at 0.1 per cent concentration of triton x 100 and one per cent concentration of glycerol, methyl-phydroxybenzoate, boric acid and carboxymethyl cellulose respectively. Laboratory bioassay studies were conducted against the second instar larvae of S litura along with one commercial formulation of B. thuringiensis var. kurstaki (DELFIN WG) and untreated control. It was found that among all Bacillus isolates maximum mortality (76.67%) was recorded in MTCC 868 at higher concentration (2.0%) after ten days of treatment. However, DELFIN WG formulation recorded maximum mortality of 99.98 per cent mortality against the second instar larvae of S. litura after seven days of treatment at all concentrations.

The production of anaerobic bacteria and biogas from dairy cattle waste in various growth mediums

Abstract: The growth of anaerobic bacteria except the ruminal fluid quailty is strongly influenced by the media formulations. Previous researchers have set a standard media formulation for anaerobic bacteria from rumen, however the use of standard media formulations require chemicals with high cost. Moreover, other constraint of using standard media formulations is requires large quantities of media for anaerobic bacteria to grow. Therefore, it is necessary to find media with a new culture media formulation. Media used in this research were minimalist media consist of Nutrient Agar (NA), Lactose broth and rumen fluid; enriched media Rumen Fluid-Glucose-Agar (RGCA); and enriched media 98-5. The dairy cattle waste is utilized as source of anaerobic bacteria. The obtained data was analyzed by descriptive approach. The results showed that minimalist media produced anaerobic bacteria 2148 × 104 cfu/ml and biogas production: 1.06% CH4, 9.893% CO2; enriched media Rumen Fluid-Glucose-Agar (RGCA) produced anaerobic bacteria...

Natural Medium for Growing of Endophytic Bacteria from Solanaceae in Malang-Indonesia

Abstract: Endophytic bacteria are important microorganisms having potential as biocontrol agents for many pathogens. Until now, the growth of it always uses semi-synthetic or synthetic medium so it was difficult to be used by farmers in the field and it was expensive to have its propagation as biocontrol agents. Based on the problem, this research will study the natural medium as propagation medium of Endophytic bacteria. It had natural ingredients such as soybean, chicken broth, egg, worms, snail, sorghum and they were easy to get by farmers. This study used endophytic bacteria from Solanaceae in Malang- Indonesia. Four isolates of endophytic bacteria were grown in agar and liquid medium with ingredients of corn flour, soybean flour, sorghum flour, snail flour, and worm flour. There is no difference in the incubation period, color, shape, and surface colony. The population in medium with snail flour ingredients at a concentration of 10 7 cfu/ml is the highest and snail flour is the best medium for growing endophytic bacteria.