Isolation, Identification, and Application of Pigment-Producing Actinobacteria from Stingless Bee Hives for Handicraft Production

Abstract

Actinobacteria are distributed in natural habitats and produce a vast variety of natural pigments that are different in colour shades and applied in textile industry and others. The extracted actinobacterial pigments are used as eco-friendly natural dyes and colour and non-toxic to living organisms and environments compared with chemical or synthetic colours. In order to produce actinobacterial pigments for handicraft making, eight strains of the pigmented producing actinobacteria were isolated from stingless bee (Tetragonilla collina Smith, 1857) hives. Based on deep colour shades presented, 4 actinobacterial strains were chosen to prepare various colour for handicrafts, including yellow, violet, green, and pink. To identify actinobacterial strains selected, phylogenetic identification was carried out. The phylogenetic results indicated that strain C2 phylogenetically shared the 16S rDNA sequence 99.6 % similarity with its closest species, namely Streptomyces cellulosae. Strain C4 had the phylogenetic relationship close to Streptomyces californicus (99.9% similarity of 16S rDNA). Strain E1 was a closest member belonged to Streptomyces chartreusis (99.9% 16S rDNA sequence similarity), and strain E2 was phylogenetically closely related to Streptomyces aureoversilis with 99.2% 16S rDNA sequence similarity. To produce the handicraft colour, we cultivated four actinobacterial strains on broken-milled rice, and actinobacterial pigments were extracted using ethyl acetate. The crude extracts obtained were mixed with white flower clay that was used for handicraft making, and the artificial clay flowers were made. This study is the first to report the use of natural colours obtained from pigment-producing actinobacteria in handicrafts in Thailand and other countries. Future research will explore the application of actinobacterial pigments in various fields, including fine arts, the ceramic industry, and others.