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Endophyte is a broad term for microorganisms that colonize asymptomatically inside the healthy tissue of a host plant and maintain mutualistic association for the whole or part of their lifecycle. Many reports are found in the current literature on endophyte-mediated secondary metabolite production in diverse plant species. Piper is a genus belonging to family Piperaceae; it is commonly known as “Paan” and is cultivated extensively in Sri Lanka, India, Thailand, Taiwan, and other Southeast Asian countries. The parts of Piper utilized are leaves, roots, stems, stalks, and fruits. The plant has a large number of biomolecules that show diverse pharmacological activity. The leaves of Piper possess bioactivities with antitumor, antimutagenic, and antihelminthic properties. Piperine and piperidine are two such alkaloids found as the active compounds in the Piper. Few endophytes producing these compounds in Piper as secondary metabolites are reported and detailed in some existing literature. Further investigation needs to be undertaken for the identification of more such piperidine and piperine-producing fungi and survey on any bacterial endophytes. A survey of more such endophytes can assist in the commercial enrichment of these bioactive molecules and can limit the overuse of respective medicinal plant materials. The present review focuses on the utilization, extraction, and shortcomings of endophyte-mediated natural product biosynthesis in the major genera of Piper with a note on future perspectives.

Endophyte is a broad term covering a variety of microscopic organisms found within the living plant cells. Commonly they are different types of fungi and bacteria engaged in interactions with the plant host varying from symbiotic to pathogenic at various instances. Secondary metabolites are the diverse array of organic compounds produced by the plants or at times by some associated microorganisms essentially involved in a variety of defense-related activities of the plants. Several plant species have been reported with endophyte-mediated secondary metabolite production. A detailed examination and study of such secondary metabolites produced by the endophytic colonizers is helping to stress the medicinal properties of such products and ultimately to focus on unlocking new drug molecules. Asiaticoside and madecassoside are two such triterpenoid molecules of plant-origin found as the active compounds chiefly in the plant Centella asiatica. Few of the endophytes producing asiaticoside and madecassoside as secondary metabolites are being explored and are reported in different existing literatures. Different standardized protocols can be employed for the purpose of specific endophyte isolation and metabolite extraction. Further investigation needs to be undertaken for the identification of more asiaticoside and madecassoside producing fungi and also any bacterial endophytes. Industrial fermentation techniques can help in mass production of the compounds. Commercial enrichment of these bioactive molecules will help in curbing the overuse of the respective medicinal plant resources. Holistic knowledge about the wider distribution of endophytic microbial counterparts depending on various conditions of plant tissues can help in consistent grasping of the role of these organisms in synthesis of the bioactive metabolites.