Yeasts are the most used microorganisms for biotechnological purposes. Although they have been mainly recognized for their application in the beverage and bioethanol industries, these microorganisms can be efficiently employed in pharmaceutical and food production companies. In these industrial sectors, yeasts are highly desirable for their capacity to produce bioactive compounds from simple substrates, including wastes. In this review, we present the state of the art of bioactive compound production in microbial cell factories and analyze the avenues to increase the productivity of these molecules, which benefit human and environmental health. The article addresses their vast biological activities, from preventing to treating human diseases and from pre to postharvest control on agroindustrial streams. Furthermore, different yeast species, genetically engineered or not, are herein presented not only as biofactories of the referred to compounds but also as their targets. This comprehensive analysis of the literature points out the significant roles of biodiversity, bioprospection, and genome editing tools on the microbial production of bioactive compounds and reveals the value of these approaches from the one health perspective.

Synthetic herbicides such as glyphosate and 2,4-D are widely used in agriculture but can negatively impact non-target organisms, including microorganisms essential for ecological balance. Yeasts associated with pollinating insects play crucial roles in plant–insect interactions, yet their responses to herbicides remain understudied. This study aimed to evaluate the capacity of yeasts isolated from bees and beetles to produce indole-3-acetic acid (IAA), a plant-growth-promoting hormone, as well as their ability to tolerate or degrade glyphosate (in the commercial herbicide Zapp QI 620^®) and 2,4-D (in the commercial Aminol 806^®). Seven yeast strains were isolated from insects, identified via ITS sequencing, and assessed for IAA production in YPD medium. Growth assays were conducted under varying herbicide concentrations, and 2,4-D degradation was analyzed using high-performance liquid chromatography. All strains produced IAA, with Papiliotrema siamensis CHAP-239 exhibiting the highest yield (4.17 mg/L). Glyphosate completely inhibited growth in all strains, while 2,4-D showed dose-dependent effects, with four strains tolerating lower concentrations. Notably, Meyerozyma caribbica CHAP-248 degraded up to 46% of 2,4-D at 6.045 g/L. These findings highlight the ecological risks herbicides pose to beneficial yeasts and suggest the potential of certain strains for bioremediation in herbicide-contaminated environments. Overall, the study underscores the importance of preserving microbial biodiversity in the context of sustainable agriculture.