Document Type : Review Article
Authors
Faculty of Pharmacy Universitas Indonesia; Depok 16424 West Java, Indonesia
Abstract
Purpose: Kratom (Mitragyna speciosa) is a tropical plant native to Southeast Asia, widely used for traditional and emerging therapeutic purposes. This review investigates the environmental and physiological determinants of phytochemical variation in Mitragyna speciosa (kratom), with a focus on optimizing alkaloid yield and raw material quality. As kratom gains commercial traction, particularly in Western markets, the need for standardizing cultivation practices becomes increasingly urgent. Findings: Geographic origin significantly influences mitragynine content, with native Southeast Asian samples displaying higher and more consistent levels than those cultivated elsewhere. Environmental factors such as light exposure, temperature, soil acidity, and nutrient composition play crucial roles in modulating both plant morphology and secondary metabolite biosynthesis. Internally, leaf maturity, organ specificity, and vein color are linked to variable alkaloid profiles, reflecting genetic and developmental influences. Alkaloid biosynthesis is regulated not only by climate and geography but also at the molecular level through gene–environment interactions. Studies across continents and related species further underscore the diversity and adaptability of the genus. These findings suggest that integrated, site-specific agronomic strategies are essential to support kratom’s evolution as a standardized phytopharmaceutical. Limitations: Most existing studies are regionally constrained, lack standardized methodology, and rarely incorporate multi-site or molecular validation, limiting their broader applicability. Directions for future research: Future work should prioritize field-based, multi-environment trials to validate the effects of environmental variables on alkaloid biosynthesis and biomass traits. In addition, controlled environment experiments, genetic profiling, and enzyme-specific biosynthetic studies are essential to refine cultivation protocols and support regulatory frameworks. Integrative agronomic and phytochemical modeling is also needed to guide the development of standardized and high-quality kratom production systems.
Keywords
- Environmental factors
- Growth optimization
- Kratom (Mitragyna speciosa)
- Physiological determinants
- Phytochemical variation
Main Subjects
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