Unraveling the Role of Lac Insects in Providing Natural Industrial Products

SIMPLE SUMMARY: Since ancient times, people have used insects, such as scale insects (lac dye, resin, and wax), honey bees (honey and wax), and silkworms (silk), to make natural products in many ways. Lac is the only natural raw material derived from insects, being obtained from several species of the genus Kerria. Lac is commercially cultivated in southeastern Asian countries, including China (Kerria yunnanensis), India (K. lacca), Thailand (K. chinensis), and Myanmar (K. nepalensis). It is non-toxic, insulating, moisture-resistant, adhesive, tasteless, and has a smooth texture. Lac has been historically employed to finish a small number of products, but it is currently used in various fields. In this review, we mainly focus on the importance of lac genes that are responsible for lac secretion. In addition, information gaps, potential future research directions, and areas that require further research are highlighted. ABSTRACT: In the current era, products made from organic materials enjoy a privileged position because of their inherent safety. The eco-friendly properties of natural lac resins have increased their demand in many industries. It is secreted by sucking insects (Hemiptera, Kerriidae) and comprises three major components, viz., resin, dye, and wax. Lac insects are generally bivoltine in nature and are distributed in tropical and sub-tropical regions with complex multi-trophic habitats. Because of their sedentary habits, lac insects are more vulnerable to predators, parasitoids, squirrels, and rats, leading to a more than 50% reduction in production yield. To increase lac production, advanced-level molecular research is required to figure out the mechanism behind lac synthesis and secretion to improve lac yield and quality. The present review highlights metamorphosis, sexual dimorphism, multi-trophic habitat, host plants, and natural enemies of lac insects, lac composition, and applications, emphasizing the role of microbes, potential lac genes, and lac synthesis mechanisms in enhancing lac quality and production. The information provided here might be useful for lac researchers and for stakeholders aiming to make their products more eco-friendly.