Statistical Optimization of α-Amylase Production from Novel Local Isolated Bacillus spp. NRC1 and Its Textile Applications

By employing Plackett–Burman design (PBD) to investigate the qualitative interactions between eleven parameters [potato shell weight, incubation time, glucose, lactose, baker's yeast, peptone, (NH₄)₂SO₄, CuSO₄, FeSO₄, CaCl₂, KCl], and central composite design (CCD), the production of α-amylase by a local bacterial isolate Bacillus spp. NRC1 using agro-industrial wastes was improved. Using a variety of waste materials, including corn cobs (CC), onion peels (OP), rice straw (RS), potato shells (PS), Molokhia stem (MS), okra suppression (OS), lemon peels (LP), and pea peels (PP), Bacillus spp. NRC1 was tested in the production of amylase. Out of the eight agro-industrial wastes tried, the highest amylase yield (6.99 U/ml) was reached using potato peels. The statistical optimization of enzyme production was carried out using PBD followed by CCD design, causing 2.06-fold and 1.51-fold increase, respectively. The overall increase was 3.11-fold. In PBD design, potato peels, peptone and (NH₄)₂SO₄ were positive factors for amylase production. The crude enzyme was tested for its ability to desize cotton fabric and subsequently studying its effect on fabric dyeability. The produced amylase proved its potentials in textile industry.