1 23 Applied Biochemistry and Biotechnology Part A: Enzyme Engineering and Biotechnology ISSN 0273-2289 Appl Biochem Biotechnol DOI 10.1007/s12010-013-0164-8 Chemical Modification of Saccharomycopsis fibuligera R64 α- Amylase to Improve its Stability Against Thermal, Chelator, and Proteolytic Inactivation Wangsa Tirta Ismaya, Khomaini Hasan, Idar Kardi, Amalia Zainuri, Rinrin Irma Rahmawaty, Satyawisnu Permanahadi, Baiq Vera El Viera, et al.