Valorization of biowastes as fermentative substrate for production of Exiguobacterium sp. GM010 pigment and toxicity effect in rats.

Bioconversion of biowastes chicken feather (CF), prawn carapace (PC), fish scale (FS), and corncob (CC) were
used for Exiguobacterium sp. GM010 pigment production to reduce environmental pollution. Maximum pigment
was produced in 4 % PC hydrolysate medium at pH 8 and 30 ◦C (0.831 Absorption Unit-AUmL− 1
) compared to
other hydrolysate. Biomass (1061.19 ± 26.14 mg/100 mL) and pigment yield (34.26 ± 0.62 mg/100 mL) were
higher in PC medium. In CF + PC hydrolysate combination, biomass and pigment yield was 890.58 ± 11.5 mg/
100 mL and 13.94 ± 0.17 mg/100 mL, respectively. Carbon and nitrogen ratio in the medium influenced
pigment production. The UV–visible spectrum showed absorption peak at 357, 466, and 491 nm. Further hue
angle (77–72) and chroma values (8.68–11.38) distributed over yellowish-orange region of CIELAB spectrum
indicated carotenoid like characteristics. Wistar rats fed with pigment (2000 mg/kg bw) did not show sign of
toxicity in haematological, biochemical and histopathological analysis. Therefore, pigment produced by recy�cling the biowastes promotes sustainable bioprocess and circular bioeconomy