Plant in vitro culture has emerged as a biotechnological approach for the sustainable production of high-value secondary metabolites. Despite advances in plant tissue culture and phytochemical research, converting biologically productive in vitro systems into reliable production platforms remains a major challenge because metabolite production alone does not necessarily reflect technological maturity. This review evaluates plant in vitro production platforms for secondary metabolites in tropical and subtropical plant species by distinguishing validated, partially validated, and emerging platforms according to their level of technological development. To support this assessment, we propose a technological validation framework based on complementary experimental evidence that distinguishes species-level scientific knowledge from platform-level technological validation. The analysis reveals substantial differences in platform development and identifies production reliability as the principal limitation preventing many systems from reaching more advanced stages of technological maturity. These findings indicate that technological maturity should be understood as a progressive process driven by the accumulation of complementary experimental evidence rather than isolated experimental achievements. Future advances in plant in vitro production will depend on integrating mechanistic understanding of secondary metabolite biosynthesis with process engineering approaches to develop robust, reproducible, and scalable production platforms, thereby facilitating the sustainable biotechnological exploitation of tropical and subtropical plant biodiversity.

The production and isolation of secondary metabolites through in vitro plant culture techniques represent a sustainable and versatile alternative to traditional cultivation. This review provides an integrative overview of the principles, methods, and advances in in vitro systems—such as callus and suspension cell cultures, hairy root cultures, micropropagation, somatic embryogenesis, and protoplast culture—highlighting their ability to exploit plant cell totipotency for the controlled synthesis of bioactive compounds with pharmaceutical, nutraceutical, and cosmetic value. These systems enable scalable, reproducible, and environmentally responsible production, supported by innovations in elicitation, metabolic engineering, and omics technologies that enhance yield and stability. Despite challenges such as high establishment costs and species-specific requirements, in vitro approaches ensure continuous metabolite production independent of climatic or ecological factors. Moreover, these biotechnological strategies open new opportunities to explore and preserve global plant biodiversity—particularly in regions rich in endemic flora, such as Ecuador—while promoting equitable access to scientific and industrial applications. Ultimately, in vitro plant culture serves as both a platform for secondary metabolite discovery and a pathway toward sustainable, inclusive, and socially impactful biotechnological development.