Antimicrobial resistance of bacterial strains isolated from orange juice products

Forty samples of twenty brands of sachet orange juice products were examined microbiologically. All the products were contaminated with bacteria and yeasts. The organisms encountered include Saccharomyces cerevisiae, Saccharomyces sp, Rhodotorula sp, Bacillus cereus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes and Micrococcus sp. The resistances of thirty bacterial strains isolated from orange juice products to the commonly used antibiotics were studied. About 66.67% of the isolates were resistant to augmentin and amoxycillin; 63.33% to cotrimoxazole, 56% to cloxacillin, and 23.33% to tetracycline. Resistances of 10, 6.67, and 3.33% were obtained for gentamicin, erythromycin and chloramphenicol respectively. Among the eight antibiotics tested, seven patterns of drug resistance were obtained. Six out of these are multiple-drug resistance with number of antibiotics ranging between 2 to 8. While MIC of amoxycillin ranged between 10-25mg/ml for the strains of E. coli, MIC of 10-20mg/ml was obtained for the strains of S. aureus. The MIC for cloxacillin was 0.1-1.0mg/ml for E. coli strains, and 0.01-1.0mg/ml for S. aureus strains. In all, ten strains of the bacterial isolates had evidence for the production of β-lactamases. Key words: Orange juice, antibiotics, resistance pattern, β-lactamase, microbiological standard. African Journal of Biotechnology Vol.3(6) 2004: 334-33

ASPECTS OF THE ISOLATION AND CHARACTERIZATON OF THERMOSTABLE &alpha -AMYLASE FROM Alternaria alternata.

A local isolate of Alternaria alternata isolated from soil under the decaying cassava peels heap was screened for the production of a-amylase and hydrolysis of starch. The maximal dextrinizing amylolytic activity of the partially purified enzyme was obtained at temperature of 600C and pH 7.0. Apart from glucose, sucrose and maltose, several other unknown products of cassava starch hydrolysis were obtained at elevated temperatures (60 – 900C). The thermostable property of the enzyme is discussed in relation to its potential in improving the nutritional quality of starchy foods and industrial usefulness in the future. KEY WORDS: Thermostable &alpha - amylase; Starch hydrolysis products; Alternaria; Starchy foods; Thin Layer Chromatography. Global Jnl Pure & Applied Sciences Vol.10(1) 2004: 75-7