In vivo studies on the prebiotic effects of Vernonia amygdalina leaf extracts

No Abstract

Correlations between antibiotic intake and resistance of some enteric gram negative bacilli to antibiotics

Some enteric Gram negative bacteria were isolated over a three – year (2006 – 2008) period from two human populations designated as population on therapy (OD) and population not on therapy (ND). Isolates were analyzed forsusceptibility to a panel of ten antibacterial agents. Results showed that OD isolates were generally more resistant to test drugs than ND isolates but the differences were not significant at both 0.01 and 0.05 levels. Pearson correlation analysis showed that the correlation in resistances among the OD and ND isolates was systematic and significant at both 0.01 and 0.05 levels, suggesting that resistance emergence and sustenance may not be an exclusive consequence of intake and misuse of antibiotics

Incidence and pathogenicity profile of Listeria sp. isolated from food and environmental samples in Nsukka, Nigeria

Samples of beef, pork, goat meat, poultry, fish and vegetables purchased from a local market located in Nsukka, Enugu State, Nigeria were examined for the presence of Listeria species. Surface swab samples taken from butchers’ tables as well as soil samples from the field where cows and pigs were kept before slaughter were examined. Listeria species were isolated from all samples except the pork and goat meat samples. The highest incidence (100%) was observed in the soil and surface swabsamples, respectively, followed by the vegetable samples (85%) and the beef samples (80%). Only Listeria monocytogenes and Listeria ivanovii were pathogenic to test animals causing death within five days. L. monocytogenes induced pathological changes characterized by abscesses in the liver, pericarditis and frank haemorrhage in the kidneys. The most notable change was the accumulation of mononuclear cells in the loose connective tissue surrounding the bile ducts. This study shows thatthere is a high incidence of listerial organisms in various key elements of the Nigerian environment, including soil and foods of both animal and plant origin, which may pose a health risk for high-risk individuals. The study goes further to establish the major target organs of attack of the pathogenic Listeria species

Production of Escherichia coli heat – Labile Enterotoxin (LT) in some artificial media and commercially available baby foods

The production of thermolabile (LT) enterotoxin on some artificial media and commercially available baby foods was studied. Staples medium, Casamino-acids-yeast extract (CA-YE) medium, Tryticase soy broth (TSB) and Syncase medium were evaluated for their ability to support the production of LT toxin. Also, nine commercially available baby foods were evaluated as substrate for LT – toxin production. Rabbit toxicity indices (RTI) showed that the staples medium served as the best artificial medium for toxin production (RTI=1.9) followed by CA-YE (RTI=1.2). Three (NA, CER and BOC), out of nine baby food brands examined supported LT-toxin production with NA giving the highest yield of toxin (RTI=2.2) determination of the electrolyte content of aspirated diarrhoeal fluid showed significant secretion of sodium (Na +) and potassium (K +) electrolytes into the fluid. These results suggest that some baby foods, when prepared and stored under non-hygienic conditions could permit growth of, as well as toxin production by toxin production bacteria and pose a health hazard for the infant population. Bio-Research Vol. 3(1) 2005: 56-6

Preliminary studies on the endo-xylanase and acetyl esterase of Clostridium thermohydrosulfuricum (JW 102)

Clostridium thermohydrosulfuricum (JW102) produced low levels of xylanase in mineral medium containing yeast extract and beechwood xylan. Production of xylanase was highest at growth temperatures of 62 – 64oC. Both xylan and xylose supported acetyl esterase production. Xylose, as sole carbon source, supported the production of slightly more acetyl esterase than xylan, while enzyme produced in the presence of xylan was relatively more stable in the fermentation medium, maintaining over 80% of peak activity after 20 hours. Acetyl esterase activity was highest at assay pH of 6.5. At pH 5.5 and 6.0, enzyme activity was, respectively, 5% and 22% of that recorded at pH 6.5. Key Words: Hemicellulases, Clostridium thermohydrosulfuricum, xylanase, acetyl esterase, beeechwood xylan. Bio-Research Vol.1(2) 2003: 1-