Exploring the Cytotoxic Effects of the Extracts and Bioactive Triterpenoids from Dillenia indica against Oral Squamous Cell Carcinoma: A Scientific Interpretation and Validation of Indigenous Knowledge.

Triterpenoids are ubiquitously distributed secondary metabolites, primarily scrutinized as a source of medication and preventive measures for various chronic diseases. The ease of isolation and excellent pharmacological properties of triterpenoids are notable reasons behind the exponential rise of extensive research on the bioactive triterpenoids over the past few decades. Herein, we attempted to explore the anticancer potential of the fruit extract of the ethnomedicinal plant Dillenia indica against oral squamous cell carcinoma (OSCC) and have exclusively attributed the efficacy of the extracts to the presence of two triterpenoids, namely, betulinic acid (BA) and koetjapic acid (KA). Preliminary in vitro screening of both BA and KA unveiled that the entities could impart cytotoxicity and induce apoptosis in OSCC cell lines, which were further well-supported by virtual screening based on ligand binding affinity and molecular dynamic simulations. Additionally, the aforementioned metabolites could significantly modulate the critical players such as Akt/mTOR, NF-κB, and JAK/STAT3 signaling pathways involved in the regulation of important hallmarks of cancer like cell survival, proliferation, invasion, angiogenesis, and metastasis. The present findings provide insight and immense scientific support and integrity to a piece of indigenous knowledge. However, in vivo validation is a requisite for moving to clinical trials and developing it as a commercial drug.

Antifungal activity of violacein purified from a novel strain of Chromobacterium sp. NIIST (MTCC 5522).

A novel strain of Chromobacterium sp. NIIST (MTCC 5522) producing high level of purple blue bioactive compound violacein was isolated from clay mine acidic sediment. During 24 h aerobic incubation in modified Luria Bertani medium, around 0.6 g crude violacein was produced per gram of dry weight biomass. An inexpensive method for preparing crystalline, pure violacein from crude pigment was developed (12.8 mg violacein/L) and the pure compound was characterized by different spectrometric methods. The violacein prepared was found effective against a number of plant and human pathogenic fungi and yeast species such as Cryptococcus gastricus, Trichophyton rubrum, Fusarium oxysporum, Rhizoctonia solani, Aspergillus flavus, Penicillium expansum, and Candida albicans. The best activity was recorded against Trichophyton rubrum (2 -g/ml), a human pathogen responsible for causing athlete-s foot infection. This is the first report of antifungal activity of purified violacein against pathogenic fungi and yeast.