Asian Journal of Biotechnology and Bioresource Technology

Microorganisms underpin a large fraction of modern food processing, industrial biotechnology, biopharmaceutical production, environmental remediation and agricultural biostimulation, yet the expression 'microorganisms of technological interest' often groups together biologically dissimilar organisms on the basis of use rather than shared taxonomy. This critical narrative review examines how microbial diversity, metabolic repertoire and process phenotype jointly determine technological value. The literature was selected through live searches of multidisciplinary and field-specific scholarly sources, with emphasis on peer-reviewed work concerning industrial bacteria, yeasts, filamentous fungi, archaea, cyanobacteria and eukaryotic microalgae. The synthesis shows that no universal microbial chassis is optimal across products. Fast-growing model organisms offer mature genetic tools, whereas non-conventional hosts can provide superior secretion, redox balance, precursor supply, substrate range or stress tolerance. Primary metabolites such as organic and amino acids illustrate mature fermentation logic, while enzymes, recombinant proteins, natural products, pigments, vitamins, biosurfactants and polyhydroxyalkanoates reveal stronger dependence on host-specific physiology and downstream recovery. Food fermentations and microbiome-based processes further demonstrate that technological function may emerge from stable communities rather than single strains. Across sectors, laboratory titre or yield is an incomplete predictor of industrial success because large-scale gradients, genetic stability, morphology, contamination control, feedstock variability, product toxicity and purification costs frequently dominate process performance. The most defensible direction for the field is therefore phenotype-to-process matching: selecting or engineering microorganisms in relation to the complete manufacturing chain rather than treating strain optimisation as an isolated metabolic problem. Future progress will depend on better non-model genetic toolkits, function-resolved community design, scale-down experimentation, dynamic control, rigorous safety assessment and integrated techno-economic and environmental evaluation. The review concludes that microbial diversity is technologically valuable when converted into predictable, robust and recoverable function at relevant scale.