Isolation and identification of phytase-producing Bacillus and Enterobacter species from Nigerian soils

The bioavailability of phosphorus and other nutrients in feed for monogastrics is restricted by the presence of phytate. Exogenous supply of phytase produced by bacteria and other microbes can enhance the bioavailability of these nutrients and reduce phosphorus pollution. The objective of the study was to isolate bacteria with phytase-producing potentials from soil; which may be employed for the bioavailability of phosphorus and other nutrients in feed for monogastrics in Nigeria. Top soil samples were collected from two dumpsites in Lagos, Nigeria and bacteria were isolated and screened for potentials to produce phytase. The isolates with phytase potential were primarily identified by their cultural and biochemical  characteristics and then confirmed using the 16S rRNA sequencing, after which their expressed phytases were quantified. A total of six isolates  belonging to three species were identified as phytase producers. Sequence data analyses revealed these to be Bacillus subtilis (2), Bacillus  amyloliquefaciens (3) and Enterobacter cloacae (1) with accession numbers MH879827 and MH879832; MH879828, MH879830 and MH879831; and MH879829 respectively. Phenotypic phytase activity was highest in E. cloacae ODS 29 (9.69 ± 0.04 U/ml) and least in B. subtilis ODS 10 (8.83 ± 0.02 U/ml). In conclusion, phytase-producing Bacillus and Enterobacter species were isolated and characterized from Nigerian soils. These bacteria species could be used in biotechnological applications. Keywords: Bacillus, Enterobacter, Monogastrics, Phylogenetic analysis, Phytas

The combined fixed-dose antituberculous drugs alter some reproductive functions with oxidative stress involvement in wistar rats

AbstractThe reproductive toxicity of combined fixed-dose first-line antituberculosis (CFDAT) regimen was assessed in rats. Thirty-two (32) Wistar rats weighing 168.1±8.0g were divided into four groups of eight rats per group. Two groups of male and female rats were administered oral distilled water (1.6ml) and CFDAT drugs containing rifampicin, isoniazid, pyrazinamide and ethambutol (RIPE, 92.5mg/m2 per body surface area) respectively for forty-five days. Serum follicle stimulating hormone, luteinizing and testosterone were reduced significantly (p<0.05) in the treated male rats. Similarly, sperm count levels were decreased by 27.3% when compared with control. RIPE elevated serum oestrogen (p<0.05), progesterone (p<0.05) as well as prolactin (p>0.05) levels in the treated females. In addition, RIPE reduced (p<0.05) total proteins levels and increased (p<0.05, 53%) catalase levels in male but not female animals. Superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, reduced glutathione levels as well as lipid peroxidation were unaltered in all rats respectively. Histopathological studies revealed congested peritesticular vessels and no changes in the ovary when compared with control. Overall, our results demonstrate reproductive toxicity potentials of RIPE in the rat, thus, suggesting that these reproductive parameters be monitored during antituberculous chemotherapy

The combined fixed-dose antituberculous drugs alter some reproductive functions with oxidative stress involvement in wistar rats

The reproductive toxicity of combined fixed-dose first-line antituberculosis (CFDAT) regimen was assessed in rats. Thirty-two (32) Wistar rats weighing 168.1 ± 8.0 g were divided into four groups of eight rats per group. Two groups of male and female rats were administered oral distilled water (1.6 ml) and CFDAT drugs containing rifampicin, isoniazid, pyrazinamide and ethambutol (RIPE, 92.5 mg/m2 per body surface area) respectively for forty-five days. Serum follicle stimulating hormone, luteinizing and testosterone were reduced significantly (p  0.05) levels in the treated females. In addition, RIPE reduced (p < 0.05) total proteins levels and increased (p < 0.05, 53%) catalase levels in male but not female animals. Superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, reduced glutathione levels as well as lipid peroxidation were unaltered in all rats respectively. Histopathological studies revealed congested peritesticular vessels and no changes in the ovary when compared with control. Overall, our results demonstrate reproductive toxicity potentials of RIPE in the rat, thus, suggesting that these reproductive parameters be monitored during antituberculous chemotherapy. Keywords: Fixed dose combined antituberculous drugs, Sub-chronic study, Reproductive toxicity, Rat