The antibacterial potential of essential oils and methanol extracts of sweet basil Ocimum basilicum L. (Lamiaceae) was evaluated for controlling the growth range of food-borne pathogenic bacteria. Essential oils extracted by hydrodistillation from the leaves and stems were analyzed by GC-MS. Fifty-seven compounds representing 94.9 and 96.1% of the total leaf and stem oils, respectively, were identified, of which methyl chavicol (36.7 and 29.9%), gitoxigenin (9.3 and 10.2%), trimethoquinol (10.3 and 8.4%), beta-guaiene (3.7 and 4.1%), aciphyllene (3.4 and 3.0%), alizarin (3.2 and 4.4%), naphthaline (2.2 and 3.8%), (-)-caryophyllene (2.0 and 1.9%), and mequinol (1.6 and 1.8%) were the major compounds. The essential oils (10 microL/disc of 1:5, v/v dilution with methanol) and methanol extracts (300 microg/disc) of O. basilicum displayed a great potential of antibacterial activity against Bacillius cereus, B. subtilis, B. megaterium, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Shigella boydii, S. dysenteriae, Vibrio parahaemolyticus, V. mimicus, and Salmonella typhi with their respective zones of inhibition of 11.2-21.1 mm and MIC values of 62.5-500 microg/mL. The results of this study suggest that the natural products derived from O. basilicum may have potential use in the food and/or pharmaceutical industries as antimicrobial agents.

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Background: Cow milk is considered as one of the responsible food sources contaminated with heavy metals. The objectives of the study were to assess the content of selected metals in cow milk and its associated human health risks in the food chain of Bangladesh. A total of 90 cow milk samples of Branded, Dairy and Domestically produced milk were collected randomly from different sources of Savar Upazila in Dhaka area. Cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), copper (Cu) and iron (Fe) contents in collected milk samples were determined using Flame Atomic Absorption Spectrometry (FAAS). To ensure quality control, one of the best quality control parameters i.e. recovery test; from eight various sample digestion methods were used. The Hazard Quotient (HQ) and Carcinogenic Risk (CR) values were also calculated. Results: From the results, it was found that, the orders of heavy metal content in brand, dairy and domestic cow milk were Cr > Fe > Cu > Mn > Cd > Pb, Cr > Fe > Mn > Cu > Cd > Pb and Fe > Cr > Mn > Cu > Cd > Pb, respectively. Among the six metals, only Cr showed to exceed the highest Estimated Daily Intake (EDI) rate (for brand cow milk: 0.413 mg/day, dairy farm cow milk: 0.243 mg/day, domestic cow milk: 0. 352 mg/day),and the comparison percentages of calculated values per permeable values were as follows; 206.5 % for brand cow milk,121.5 % for dairy farm cow milk and 176.0 % for domestic cow milk. Hazard Quotients (HQ) values and Carcinogenic Risk (CR) values were found within the acceptable level. Conclusion: Although, the metal content in sampled cow milks were within the safe limit, the potential human health risks cannot be neglected for the regular/long time consumption of heavy metal contained cow milk.

The effect of gamma radiation on the shelf life extension of Bananas was studied. Bananas were treated with three gamma radiation doses of 0.30k Gy; 0.40k Gy and 0.50k Gy for 5 mins respectively and stored in a dry place under room conditions (25±2°C/ 80± 5% RH). The physical conditions of the radiation treated and control bananas were observed at every 2 days interval for their organoleptic properties till spoilage. The control bananas ripened within 6 days while the gamma irradiated bananas ripened within 26 days, indicating that t he shelf life of banana was extended by 20 days thereby delaying banana ripening. The nutrient contents as well as some important physico-chemical parameters of the irradiated Bananas and the control Bananas were analyzed quantitatively at an interval of 2-4 days throughout the experimental period. A minor decrease in the ascorbic acid content was the only adverse effects observed in irradiated bananas and no other major changes occured in nutritional and organoleptic qualities and the chemical constituents of banana is maintained. A taste-testing panel of 16 panelists determined the acceptability of the fruit. The scores given by the panelists were statistically analyzed and the treated bananas were found to be acceptable up to 26 days at room temperature whereas in the case of control the fruits were spoiled within 6 days. Thus, radiation can be used for the shelf life extension of Bananas and is not harmful to health.

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