Research Projects

Piperine is an economically important plant alkaloid that is used in pharmaceutical, food, nutraceutical, and pesticide industries. It is traditionally obtained from dried spikes and/or roots of Piper spp., mainly Piper nigrum and P. longum. The plant-based extraction of piperine is limited by its low abundance, destructive harvesting of roots, risky extraction procedures, and dependency on season and development stage. Considering the rising demand of piperine, which is estimated to reach ~$8.8 billion by the year 2028 (https://www.expertmarketresearch.com/reports/piperine-market), there is a need to find an alternative source of piperine. Therefore, to resolve this issue, we adopted a microbiome approach involving characterization of P. longum endophytes using culture-dependent (Mintoo et al., 2019; Phurailatpam et al., 2022, 2024) and metagenomic approaches (Mishra et al., 2021, Mishra and Sharma, 2023). Out of the 96 bacterial and 26 fungal endophytes isolated from different surface-sterilized plant parts, we found three endophytic fungi (namely R5, Sp4 and S8) with the ability to produce piperine in the cell-free supernatant fraction of the cultures grown under stationary conditions for 21 days at 28 °C. The in vitro fungal cultures have been found to produce piperine (even after more than 10 rounds of subculturing/passaging), as confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed study aims to understand the mode of fungal piperine production, i.e. whether horizontal gene transfer (between the plant and endophytic fungi) or evolution of an independent biosynthetic pathway in the fungal strains is responsible for endophyte-mediated piperine production. Further, the objective is to delineate the fungal biosynthetic gene clusters (BGCs) involved in piperine production in the three strains. Finally, a piperine biosynthetic gene identified from the BGCs will be functionally characterized in the model system, yeast. Overall, the rationale behind the proposed study is to provide a proof-of-concept for the occurrence of plant metabolite biosynthetic pathway in microbial endophytes, which could be targeted for sustainable production of rare, high-value phytochemicals. Engineering of fungal piperine biosynthetic genes is a more feasible approach for obtaining secondary metabolites efficiently and sustainably. Besides, the work will also enable the detection of silent BGCs in the fungal genomes which could be activated to derive a diverse array of bioactive compounds.