RESEARCH ARTICLE Production of α-1,4-glucosidase from Bacillus licheniformis KIBGE-IB4 by utilizing sweet potato peel Muhammad Asif Nawaz 1,2 & Zainab Bibi 3 & Asad Karim 4 & Haneef Ur Rehman 5 & Muhsin Jamal 6 & Tour Jan 7 & Afsheen Aman 2 & Shah Ali Ul Qader 2 Received: 20 June 2016 /Accepted: 28 November 2016 # Springer-Verlag Berlin Heidelberg 2016 Abstract In the current study, sweet potato peel (Ipomoea batatas) was observed as the most favorable substrate for the maximum synthesis of α-1,4-glucosidase among various agro-industrial residues. Bacillus licheniformis KIBGE-IB4 produced 6533.0 U ml -1 of α-1,4-glucosidase when growth medium was supplemented with 1% dried and crushed sweet potato peel. It was evident from the results that bacterial iso- late secreted 6539.0 U ml -1 of α-1,4-glucosidase in the pres- ence of 0.4% peptone and meat extract with 0.1% yeast ex- tract. B. licheniformis KIBGE-IB4 released 6739.0 and 7190.0 U ml -1 of enzyme at 40 °C and pH 7.0, respectively. An improved and cost-effective growth medium design result- ed 8590.0 U ml -1 of α-1,4-glucosidase with 1.3-fold increase as compared to initial amount from B. licheniformis KIBGE- IB4. This enzyme can be used to fulfill the accelerating de- mand of food and pharmaceutical industries. Further purifica- tion and immobilization of this enzyme can also enhance its utility for various commercial applications. Keywords Biodegradation . Agro-industrial waste . Maltase . Fermentation . Industrial applications Introduction α-1,4-Glucosidase [EC 3.2.1.20, maltase] is an amylolytic enzyme that accelerates the hydrolytic process of maltose by cleaving α-1 → 4 glucosidic linkages and releases α-D-glu- Highlights • Various agro-industrial wastes and pure substrates were evaluated as feedstock for α-1,4-glucosidase production. • α-1,4-Glucosidase production was optimized using sweet potato peel as a sole carbon source. • Incorporation of organic nitrogen sources in growth medium promoted the enzyme synthesis. • Broad thermal and pH stability profile indicated its utility in various industrial bioprocesses. Responsible editor: Philippe Garrigues * Muhammad Asif Nawaz asif_biotech33@sbbu.edu.pk * Zainab Bibi zainabb.bibi@gmail.com 1 Department of Biotechnology, Shaheed Benazir Bhutto University, Sheringal, Dir Upper, KPK, Pakistan 2 The Karachi Institute of Biotechnology and Genetic Engineering (KIBGE), University of Karachi, Karachi 75270, Pakistan 3 Department of Biotechnology, Federal Urdu University of Arts, Science, and Technology, Karachi, Pakistan 4 National Institute of Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan 5 Department of Chemistry, University of Turbat, Kech, Balochistan, Pakistan 6 Department of Microbiology, Abdul Wali Khan University, Garden Campus, Mardan, Pakistan 7 Department of Botany, University of Malakand, Chaldara, KPK, Pakistan Environ Sci Pollut Res DOI 10.1007/s11356-016-8168-x