Nisin Peptide as Promising Natural Food Preservative for Food (Published)
Sodium Nitrite has been widely use as preservative for meats and fish Products, but in recent years there has been considerable interest for searching about natural Food preservatives like Nisin peptide. The aim of this study was to compare the inhibitory effect of two preservatives were Sodium Nitrite and Nisin peptide separately against Staphylococcus Aureus (Staph. A), Escherichia coli (E. coli), and Candida Albicans (C. Albicans) in Mueller Hinton Broth (MHB) at three different pH (7.0- 6.0- 5.5). After that the combination effect between Sodium Nitrite and Nisin was studied in MHB at optimum pH that was concluded from the previous stage. Minimal Inhibitory Concentrations (MIC) and Minimal Bactericidal Concentrations (MBC) of both preservatives were evaluated. FIC values (Fractional Inhibitory Concentration) were calculated after combination between them. The results showed that MIC values of Sodium Nitrite against S. Aureus, E. coli and C. albicans at pH 5.5 were (500- 200- 500) ppm respectively and MIC values of Nisin were (100- 350- 500) ppm respectively, while MIC values of the combination (Sodium Nitrite+ Nisin) against S. A, E. coli and C. albicans were (50- 25- 100) ppm respectively and FIC values of them were (0.39- 0.15- 0.30). On the other hand The results showed that simultaneous use of Nisin with sodium nitrite reduced MIC and MBC of this compound against bacteria and fungi Significantly consequently, this synergistic effect of Nisin could promote in the Future to reduce of the using of Sodium Nitrite in food industry.
Keywords: Bacteria, FIC., MIC, Nisin, Synergism
MICROBIOLOGICAL AND PHYSICOCHEMICAL STUDIES OF TWO NIGERIAN FERMENTED ALCOHOLIC DRINKS (PALMWINE AND BURUKUTU) IN EKITI STATE, NIGERIA. (Published)
Palm wine samples were collected from five (5) different towns in Ekiti State while burukutu were also collected from three different towns in Ekiti State. The pH of the palm wine ranged from 4.49 in sample PWB (Are- Ekiti) to 5.23 in PWD (Ikere-Ekiti). In the chemical analysis, total alkalinity ranged from 0.03% in PWA (Ado-Ekiti), PWD and PWE (Ikole-Ekiti) to 0.06 in PWB. Total solids ranged from 10.670 Brix in PWA to 16.57 in sample PWC (Ifaki-Ekiti). Total reducing sugar ranged from 10.81% in sample PWA to 18.94% in PWC while protein ranged from 0.31mg/l in PWE to 0.34mg/l in PWB and PWC. In the total bacteria count (TBC), it ranged from 0.9 X 105 cfu/ml in PWC to 2.3 X 105 cfu/ml in PWA. TBC in burukutu has the highest value of 8 in sample BK (Ado -Ekiti) and lowest of 4.9 in sample BM (Ikere-Ekiti). Total yeast count, ranged from 1 in PWB to 6 in PWD. For the burukutu sample, it ranged from 4 in sample BL (Ikole-Ekiti) to 88 in BK. In all, 2.9 x 10 microorganisms were isolated from the palm wine samples with 1.2 x 10 yeast cells and 1.7 x 10 bacteria cells. From the microbial load on the samples, 5 bacteria genera were isolated. Consumption of these alcoholic beverages are therefore not safe, as contaminants have been observed in the drinks and these contaminants and pathogens are dangerous as consumption can result to health hazard
Keywords: Alcoholic Beverages, Bacteria, Burukutu, Palmwine, Yeast