Aflatoxin Contamination in Agricultural Commodities.

Aflatoxin is a naturally occurring Mycotoxin produced by Aspergillus flavus and Aspergillus parasiticus. Aspergillus flavus is common and widespread in nature and is most often found when certain grains are grown under stressful conditions such as draught. The mold occurs in soil, decaying vegetation, hay and grains undergoing microbiological deterioration and invades all types of organic substrates whenever and wherever the conditions are favourable for its growth. Favourable conditions include high moisture content and high temperature.The aflatoxin group is comprised of aflatoxin B1,B2,G1 and G2. In addition , aflatoxin M1 (AFM1), a hydroxylated metabolite of AFB1, is excreted in the milk of dairy cows consuming an AFB1-contaminated ration. Aflatoxin B1 a prototype of the aflatoxins, is widely recognized as the most potent hepato carcinogenic compound and along with other certain members of the group, possess additional toxic properties including mutagenicity, tetrogenicity, acute cellular toxicity and it suppresses the immune system. Aflatoxin contamination of food and feed has gained global significance as a result of its deleterious effects on human as well as animal health. The marketability of food products is adversely affected by aflatoxin contamination.

Isolation and Quantification of Aflatoxin from Aspergillus flavus Infected Stored Peanuts.

Isolates of Aspergillus infected Peanuts were separately grown on modified Czapek’s medium at 280 C and the metabolites were tested for aflatoxin by HPLC. Naturally infected peanuts collected from trader’s godown were tested for aflatoxins. Aflatoxins are considered to be one of the most dangerous contaminants in food and feeds. Aflatoxins are a special group of naturally occurring metabolites produced by the fungi aflatoxins B1, B2, G1 and G2 which contaminate a variety of agricultural food and feed products .Naturally infected peanuts from Aspergillus flavus stored at trader’s godown, after several months’ storage, were found to be contaminated with aflatoxin B1.

Antimicrobial activity and Characterization of Marine bacteria.

Marine bacteria were isolated from seawater was collected from different coastal areas of the Tamilnadu Sea. The antimicrobial activities of these bacteria were investigated. Ethyl acetate extracts of marine bacterial fermentation were screened for antimicrobial activities using the method of agar diffusion. The results showed that 25 strains of the isolates have antimicrobial activity. The proportion of active bacteria associated with isolated from seawater. The active marine bacteria were assigned to the genera Alteromonas, Pseudomonas, Bacillus and Marinobacter. The TLC autobiographic overlay assay implied that the antimicrobial metabolites produced by four strains with wide antimicrobial spectrum were different. These marine bacteria were expected to be potential resources of natural antibiotic products. It can be concluded that isolation of Marine bacterial samples can offer a numbers of microbial strains for sources of new biomolecules from Marine sources.

Evaluation of Phytochemical Constituents of Indian Medicinal Plant Hydnocarpus alpina WIGHT.

Hydnocarpus alpina WIGHT. is a evergreen forest plant. It is an endemic plant to western ghats of India. Several local names are available based on distribution among the state in india that is Torathi (kanada), Maravetti (Malayalam), attuchankalai (tamil), kastel (hindi). This tree has very appreciated value in the aspect of medicine. It has anti-larvicidal, anti-feedant, anti-microbial and etc. It has the medicinal properties due to the presence of its significant chemical constituents. In this paper revealed that the IR spectrum and chemical constituents which are present in different solvents (chloroform, pet.ether, ethanol, water).

Effect of systemically administered nitric oxide donor, sodium nitroprusside on picrotoxin-induced convulsions in rats.

Nitric oxide (NO), the gaseous neurotransmitter has been reported to have an endogenous anticonvulsant property. This has prompted proposals to develop NO donors as anticonvulsant drugs. In the present study, the effect of NO donor, sodium nitroprusside (SNP) on picrotoxin (PCT)-induced convulsions was investigated. A convulsant dose of PCT (5 mg/kg) was administered 5, 10, 15 and 30 min after intraperitoneal injection of graded doses (0.7, 1.25 and 2.5 mg/kg) of SNP. SNP at doses 0.7 and 1.25 mg/kg increased dose dependently the severity of PCT-induced convulsions. But, pretreatment with the higher dose (2.5 mg/kg) of SNP was protective against PCT-induced convulsions. However, post treatment (5 and 10 min) with the same dose exacerbated convulsions and caused death of the animals. These results indicate that the vasodilator effect of SNP and an increased perfusion of PCT into brain may be responsible for the proconvulsant action of SNP. A decreased entry of PCT because of marked vasodilation and hypotension has been speculated for an inhibition of convulsions in animals pretreated with a higher dose of SNP. In conclusion, the results reveal the non-suitability of SNP to be developed as an anticonvulsant.