Characterization and application of dried neem leaf powder as a bio-additive for salt less animal skin preservation for tanneries.

Sodium chloride (NaCl) is commonly used as a curing/preservative agent for raw hides and skins in tanneries and is removed through a soaking process with total dissolved solids (TDS) and other organic pollutants in effluent, causing significant pollution load to the environment. Hence, the present study evaluated to apply dried neem leaf powder (DNL) as an additive to reduce the usage of salt in skin processing and preservation. To make certain of DNL antimicrobial properties, solvent extracts were performed against proteolytic bacteria isolated from raw skins. Initial characterization of DNL revealed the presence of bioactive compounds nimbolide and dehydro salannol and acetone extract with 16.9-mm, 10-mm and 8-mm zone of inhibition against Salmonella sp., E. coli sp. and Bacillus sp. identified using phenotypic conventional biochemical screening method. Further, skin curing experiments were carried out using four different treatments of DNL (10% 15%, 20% and 25% w/w) along with 15% w/w of conventional salt to obtain an optimum concentration for pilot-scale studies. Thus, the application of optimal DNL (15%) and salt (15%) resulted in no physical changes such as smell and hair slip and was taken for further studies for hydroxyproline activity, pollution load and organoleptic properties along compared with control 40% salt. DNL-aided salt less preservation of freshly flayed goat skins at ambient condition showed no hair slip or putrefaction during the preservation period with significant reduction of TDS (86%) and chloride (71%) in soak liquors compared to conventional salt preservation and enhanced organic load requiring additional treatment. However, the application of the organoleptic, physical and hydrothermal properties of resulting leathers produced from the DNL applied skins was on par with results of leather obtained from conventional salt. Thus, our results demonstrate DNL-aided salt less preservation method is able to reduce the amount of salt for preservation of goat skins significantly, leading to reduced salinity issues during leather processing.

Vernodalin induces apoptosis through the activation of ROS/JNK pathway in human colon cancer cells.

Colorectal cancer is one of the most leading death-causing cancers in the world. Vernodalin, a cytotoxic sesquiterpene, has been reported to possess anticancer properties against human breast cancer cells. We aimed to examine the anticancer mechanism of vernodalin on human colon cancer cells. Vernodalin was used on human colon cancer cells, HT-29 and HCT116. The cytotoxicity of vernodalin on human colon cancer cells was determined through in vitro 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay. Small interfering RNA was used to analyze the cascade activation of mitogen-activated protein kinase (MAPK) pathway, c-Jun N-terminal kinase (JNK) in HT-29, and HCT116 cells against vernodalin treatment. The protein expressions of caspase 3, Bcl-2, and Bax were examined through Western blot analysis. Immunoblot analysis on the JNK, ERK, and p38 MAPK pathways showed increased activation due to vernodalin treatment. It was proven from the JNK and p38 inhibition test that both pathways are significantly activated by vernodalin to induce apoptosis. Our results, collectively, showed the apoptosis-induced anticancer mechanism of vernodalin on human colon cancer cells that was mediated through the activation of JNK pathway and apoptotic regulator proteins. These results suggest that vernodalin could be developed as a potent chemotherapeutic agent for human colorectal cancer treatment.