The optimal conditions were obtained by the Circumscribed Central Composite design method using the Modde software. Optimal values for this process were found at pH9, ratio of material to buffer 1:9 (wmaterial/vbuffer), temperature oC, and time within minute. After ultrasound treatment, hydrolysis using the enzyme Alcalase was performed under the following conditions: ratio enzyme to substrate 4 % (v/w), temperature 55 oC, and time 60 minutes. | Vietnam Journal of Science and Technology 56 (4A) (2018) 127-137 EXTRACTION OF CHONDROITIN SULFATE FROM CHICKEN KEEL CARTILAGE BY COMBINED APPLICATIONOF ULTRASOUND TREATMENT AND ALCALASE HYDROLYSIS Truong Ngoc Thao*, Vu Nguyen To Nhu, Nguyen Thi Nguyen, Dong Thi Anh Dao* Dept. Food Technology, Ho Chi Minh city University of Technology, 268 Ly Thuong Kiet, 10 District, Ho Chi Minh City * Email: dtanhdao@; truongngocthao1995@ Received: 13 July 2018; Accepted for publication: 9 October 2018 ABSTRACT Chondroitin sulfate (CS) is a glycosaminoglycan composed of N-acetyl-D-galactosamine and D-glucuronic acid sulfated at positions 4 or 6. Chondroitin sulfate is used in functional food for supporting treatment of arthritis. Chicken keel cartilages, a by-product of the poultry slaughter industry, can be used as a source for CS production. Our study was undertaken to extract CS from chicken keel cartilages by the combined application of ultrasound treatment and Alcalase hydrolysis. The variables of the ultrasound treatment process, such as ratio of material and buffer, pH, temperature, and time were investigated. The optimal conditions were obtained by the Circumscribed Central Composite design method using the Modde software. Optimal values for this process were found at pH9, ratio of material to buffer 1:9 (wmaterial/vbuffer), temperature oC, and time within minute. After ultrasound treatment, hydrolysis using the enzyme Alcalase was performed under the following conditions: ratio enzyme to substrate 4 % (v/w), temperature 55 oC, and time 60 minutes. HPLC analysis showed that the powder product contained % CS with an average molecular weight of kDa (determined by GPC). The overall yield of CS was % of the absolute dry weight, and % of the total carbohydrate content of the starting material. Keywords: glycosaminoglycans, chondroitin sulfate, alcalasehydrolysis, chicken keel cartilage, ultrasound treatment. 1. .
