Kaulath, a new fungal fermented food from horse gram.

Horse gram (Macrotyloma uniflorum) is used in the traditional method for treatmentof several health complications. It is also known that fermentation of such substrates yields a number of compounds that enhance the overall activities against several disease states. Solid state fermentation of horse gram using Penicillium camemberti showed an inhibition of pancreatic lipase and alpha glucosidase activities. The fermented material, termed Kaulath, showed 60 % increase in fat content. A reduction in sodium and increased levels of potassium and calcium was observed in Kaulath. In addition, a higher free radical scavenging activity was noted in this product compared to unfermented horse gram. Anti-nutritional factors, such as phytic acid and trypsin inhibitors showed a reduction in Kaulath. Furthermore, Kaulath, upto 1 g per kg body weight, did not exhibit any mortality or toxic effects in experimental rats after 14 days of administration. The hematological and clinical parameters were within safe limits between the groups, supported by the histopathology of liver and kidney. These results indicate potential food use of Kaulath in diets and as functional ingredients in formulated foods.

Sclerotiorin is non-mutagenic and inhibits human PMNL 5-lipoxygenase and platelet aggregation.

Sclerotiorin, isolated from the fermented broth of Penicillium frequentans, exhibited potent inhibition against human polymorphonuclear leukocytes 5-lipoxygenase and human platelet aggregation with a half maximal value 36 µM and 250 µM, respectively. Further, the Ames test has demonstrated the sclerotiorin to be non-mutagenic.

A tyrosinase inhibitor from Aspergillus niger.

Tyrosinase, in the presence of oxygen, is the main culprit in post harvest browning of food products, resulting in the drop in its commercial value. In an effort to seek natural tyrosinase inhibitors for food applications, a screening programme was undertaken. Of the 26 fungal cultures isolated from soil samples of Agumbe forest, India, one isolate S16, identified as Aspergillus niger, gave an inhibition of 84 % against the enzyme. The inhibitor was isolated by following an enzyme inhibition assay guided purification protocol. The structure of the inhibitor was elucidated and found to be kojic acid. The IC50 of the Competitive inhibitor was found to be 8.8 µg with a Ki of 0.085 mM.

Rapid screening of enzyme inhibitors using profiling of enzyme-metabolite assay by HPLC (PREMA-HPLC).

A number of isolates from different ecosystems were screened for their ability to inhibit tyrosinase resulting in the selection of isolate CFR 101, which showed an inhibition of 72%. The metabolites present in the crude extract of the selected isolate was profiled through high-performance liquid chromatography (HPLC) before the enzyme inhibition assay to reveal a 66% decrease in area of the peak at room temperature for 13.9 min, after the assay. Upon purification, this peak was identified as kojic acid, a known inhibitor of tyrosinase. This unique technique of combining a reaction assay mixture with HPLC profile wherein inhibitors can be rapidly pinpointed in crude extracts addresses the drawback of rapid chemical high-throughput screening (HTS) systems, which is limited to the chemical nature of metabolites without any evidence of their biological activities.