Identification of Aflatoxigenic Fungi and Detection of Their Aflatoxin in Red Chilli (<i>Capsicum annuum</i>) Samples Using Direct Cultural Method and HPLC

Aflatoxins are the potential lethal toxin produced by Aspergillus sp. important health hazard throughout the world. In this study, 26 Aspergillus sp. have been isolated from 50 samples of red chilli collected throughout the country. These 26 isolates were grown primarily on agar media to identify the aflatoxin producing species. It is possible to distinguish A. flavus strains from other Aspergillus sp. developing orange colour on the reverse of the plates. The Coconut Cream Agar (CCA) is used to detect aflatoxin producer strains having blue fluorescence when exposed to a UV-light. Several other media were used for morphological characteristics of Aspergillus sp. Out of 26 isolates, four isolates were confirmed as Aspergillus sp. These isolates were subjected to cross contamination with freshly ground, sterile maize and after 15 days of incubation the contaminated maize were analyzed by HPLC and found aflatoxin in each of the sample containing 186 ppb (max.). This study was conducted to assay the ability to produce aflatoxins by the Aspergillus spp. isolated from red chilli (Capsicum annuum L. Solanaceae) available throughout the country. The results found in the experiment are much more behind the acceptable limit according to some international standard. As red chilli is a widely used spice in Bangladesh, the proper controlling measures may be taken for controlling the surveillance of aflatoxinic fungi like as use of bio-pesticides, proper drying method and storage conditions.

Anti-ulcerogenic activity of aqueous extract of Carica papaya seed on indomethacin-induced peptic ulcer in male albino rats

OBJECTIVE： Carica papaya is an important fruit with its seeds used in the treatment of ulcer in Nigeria This study investigated the anti-ulcerogenic and antioxidant activities of aqueous extract of Carica papaya seed against indomethacin-induced peptic ulcer in male rats. METHODS： Thirty male rats were separated into 6 groups （A-F） of five rats each. For 14 d before ulcer induction with indomethacin, groups received once daily oral doses of vehicle （distilled water）, cimetidine 200 mg/kg body weight （BW）, or aqueous extract of C. papaya seed at doses of 100, 150 or 200 mg/kg BW （groups A, B, C, D, E and F, respectively）. Twenty-four hours after the last treatment, groups B, C, D, E and F were treated with 100 mg/kg BW of indomethacin to induce ulcer formation. RESULTS： Carica papaya seed extract significantly （P〈0.05） increased gastric pH and percentage of ulcer inhibition relative to indomethacin-induced ulcer rats. The extract significantly （P〈0.05） decreased gastric acidity, gastric acid output, gastric pepsin secretion, ulcer index and gastric secretion volume relative to group B. These results were similar to that achieved by pretreatment with cimetidine. Specific activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase in the extract-treated groups （D, E and F） were increased significantly over the group B （P〈0.05）. Pretreatment with the seed extract protected rats from the indomethacin-mediated decrease in enzyme function experienced by the group B. Similarly, indomethacin-mediated decrease in reduced glutathione level and indomethacin-mediated increase in malondialdehyde were reversed by Carica papaya extract. CONCLUSION： In this study, pretreatment with aqueous extract of Carica papaya seed exhibited anti- ulcerogenic and antioxidant effects, which may be due to the enhanced antioxidant enzymes.