Objective: To evaluate methanolic, ethanolic, acetone and aqueous extracts from different parts of Eurycoma longifolia (E. longifolia) (leave, stem, and root) for antibacterial activity against Gram-positive and Gram-negative bacteria and to utilize the leaves and stem parts rather than the root, which is already used for male sexual enhancement in Malaysia.
Methods: The study took place in the Laboratory of Molecular Biology of Biotechnology Engineering Department, Malaysia between January 2005 and June 2006. Methanolic, ethanolic, acetone and aqueous extracts of leaves, stems and roots of E. longifolia were investigated for their antibacterial properties using Agar-well diffusion method.
Results: The alcoholic and acetone extracts of the leaves and stem extracts were active on both Gram-positive and Gram-negative bacteria except against 2 strains of Gram-negative bacteria (Escherichia coli and Salmonella typhi). The root extracts had no antibacterial activity against Gram-positive and Gram-negative bacteria tested. Aqueous leaves extract showed antibacterial activity against Staphylococcus aureus and Serratia marscesens.
Conclusion: The alcoholic and acetone extracts from leaves and stems of E. longifolia contain potent antibacterial agent(s). This plant can serve as a potential source of antibacterial compounds.
Table eggs are an affordable yet nutritious protein source for humans. Unfortunately, eggs are a vector for bacteria that could cause foodborne illness. This study aimed to investigate the effectiveness of a quaternary ammonium compound (quat) sanitizer against aerobic mesophilic bacteria, yeast, and mold load on the eggshell surface of free-range and commercial farms and the post-treatment effect on microbial load during storage. Total aerobic mesophilic bacteria, yeast, and molds were enumerated using plate count techniques. The efficacy of the quaternary ammonium sanitizer (quat) was tested using two levels: full factorial with two replicates for corner points, factor A (maximum: 200 ppm, minimum: 100 ppm) and factor B (maximum: 15 min, minimum: 5 min). Quat sanitizer significantly (p < 0.05) reduced approximately 4 log10 CFU/cm2 of the aerobic mesophilic bacteria, 1.5 to 2.5 log10 CFU/cm2 of the mold population, and 1.5 to 2 log10 CFU/cm2 of the yeast population. However, there was no significant (p ≥ 0.05) response observed between individual factor levels (maximum and minimum), and two-way interaction terms were also not statistically significant (p ≥ 0.05). A low (<1 log10 CFU/cm2) aerobic mesophilic bacteria trend was observed when shell eggs were stored in a cold environment up to the production expiry date. No internal microbial load was observed; thus, it was postulated that washing with quat sanitizer discreetly (without physically damaging the eggshell) does not facilitate microbial penetration during storage at either room temperature or cold storage. Current study findings demonstrated that the quat sanitizer effectively reduced the microbial population on eggshells without promoting internal microbial growth.
Over two hundred bacteria were isolated from the halosphere, rhizosphere and endophyte of Malaysian maize plantation and screened for phytases activity. Thirty isolates with high detectable phytase activity were chosen for media optimization study and species identification. Ten types of bacterial phytase producers have been discovered in this study, which provides opportunity for characterization of new phytase(s) and various commercial and environmental applications. The majority of the bacterial isolates with high detectable phytase activity were of endophyte origin and 1.6% of the total isolates showed phytase activity of more than 1 U/ml. Most of the strains produced extra-cellular phytase and Staphylococcus lentus ASUIA 279 showed the highest phytase activity of 1.913 U/ml. All 30 species used in media optimization study exhibit favorable enzyme production when 1% rice bran was included in the growth media.