Microsoft Word LA 07 06 docx 89 CHƯƠNG 4 KẾT LUẬN VÀ KIẾN NGHỊ 4 1 Kết luận Về mặt khoa học Luận án đã rút ra được những kết luận mới sau Bốn loại enzyme lipase được sử dụng để khảo sát quá trình thủy phân dầu dừa VCO là chế phẩm enzyme PPL, enzyme Lypozyme TL 100L, enzyme Lypozyme TL IM, đều đặc hiệu vị trí xúc tác sn 1,3 trên mạch triglyceride và chế phẩm enzyme CRL không đặc hiệu vị trí xúc tác Kết quả là, enzyme CRL xúc tác phản ứng thủy phân dầu VCO có giá trị Km nhỏ nhất và vận tốc phản ứn.
CHƯƠNG KẾT LUẬN VÀ KIẾN NGHỊ 4.1 Kết luận Về mặt khoa học Luận án rút kết luận sau: - Bốn loại enzyme lipase sử dụng để khảo sát trình thủy phân dầu dừa VCO chế phẩm enzyme PPL, enzyme Lypozyme TL 100L, enzyme Lypozyme TL IM, đặc hiệu vị trí xúc tác sn-1,3 mạch triglyceride chế phẩm enzyme CRL khơng đặc hiệu vị trí xúc tác Kết là, enzyme CRL xúc tác phản ứng thủy phân dầu VCO có giá trị Km nhỏ vận tốc phản ứng cực đại (Vmax) cao bốn loại enzyme lipase khảo sát - Hỗn hợp acid béo tự (FFA tổng) thu từ trình thủy phân dầu VCO có hoạt tính kháng khuẩn lên bốn loại vi khuẩn gồm Salmonella enteritidis (ATCC 13076), Staphylococcus aureus (ATCC 25923), Bacillus subtilis (ATCC 11774) Escherichia coli (ATCC 25922) Sau tách phân đoạn hỗn hợp FFA tổng khả kháng khuẩn phân đoạn khơng giống nhau, thể theo mức độ tăng dần sau: FFA tổng < FFA2 < FFA1 Riêng FFA3 hoạt tính kháng khuẩn lên bốn loại vi khuẩn - Các phân đoạn acid béo có ảnh hưởng khác đến trọng lượng số cholesterol chuột giống Wistar cho ăn chế độ giàu béo HFD sau: + FFA1 giúp giảm trọng lượng giảm số cholesterol tổng chuột ăn chế độ HFD + FFA2 giúp giảm trọng lượng tăng số cholesterol tốt (HDL-cholesterol) + FFA3 làm tăng trọng lượng chuột mà gây viêm gan Tuy nhiên, số cholesterol máu giảm tương đương với chuột đối chứng không bệnh 89 Về mặt ứng dụng Luận án xác định được: - Đã chọn enzyme CRL thủy phân dầu VCO với tỉ lệ dầu/đệm: 1/5 (w/w), tỉ lệ E/S: 5310U/g, pH nhiệt độ 40oC, sau 16 xúc tác đạt mức độ thủy phân lên đến 79,64% hàm lượng MCFA giải phóng đến 61,37% - Ở nhiệt độ 145 – 150oC áp suất 7,5mmHg, hỗn hợp acid béo tự FFA1 chứa chủ yếu MCFA 97,31% thu nhận FFA2 thu nhận áp suất với nhiệt độ cao 160 – 165oC, thành phần chủ yếu C12 chiếm tỉ lệ cao hỗn hợp 76,49% Phần cịn lại bình cầu FFA3 chứa chủ yếu acid béo tự mạch dài LCFA 85,86% 4.2 Kiến nghị Cần có nghiên cứu để: - Xác định chế kháng khuẩn MCFA thu nhận từ dầu VCO - Xác định liều lượng sử dụng MCFA để tránh tượng “gan thối hóa mỡ mức độ vừa” đảm bảo giảm trọng lượng giảm số cholesterol chuột 90 DANH MỤC CƠNG TRÌNH ĐÃ CƠNG BỐ Tạp chí quốc tế Van T.A Nguyen, Truong D Le, Hoa N Phan, and Lam B Tran, “Antibacterial Activity of Free Fatty Acids from Hydrolyzed Virgin Coconut Oil Using Lipase from Candida rugosa,” J Lipids, vol 2017, pp 1–7, 2017 (Scopus) Van T.A Nguyen, Truong D Le, Hoa N Phan, and Lam B Tran, “Hydrolysis Activity of Virgin Coconut Oil Using Lipase from Different Sources,” Scientifica, vol 2018, pp 1–7, 2018 (Scopus) Van T A Nguyen, Truong D Le, Hoa N Phan, and Lam B Tran, “Isolating free fatty acid from virgin coconut oil using lipase from different sources,” Jurnal Teknologi, vol 3, pp 55–59, 2018 (Scopus) Tạp chí nước Van T.A Nguyen, Tuan M Pham, Duy H Truong, and Hoa N Phan, “Antibacterial activity of hydrolyzed virgin coconut oil by immobilized lipase,” Journal of Science and Technology, vol 54, 2016 Kỷ yếu hội nghị quốc tế Van T A Nguyen, Hoa N Phan, and Lam B Tran, "Enzymatic hydrolysis of coconut oil using lipases from Candida rugosa and porcine pancreas", The 2nd International Conference on Chemical Engineering, Food and Biotechnology 2015, ISBN: 978-604-63-1598-8 Van T A Nguyen, Hoa N Phan, and Lam B Tran, "Hydrolysis of virgin coconut oil using free and immobilized lipase from Apergillus Oryzae" proceeding of the 2016 International Conference on Advanced Technology and Sustainable Development, ISBN: 978-604-920-040-3 91 TÀI LIỆU THAM KHẢO [1] A M Marina, Y B Che Man, S A H Nazimah, and I Amin, “Chemical properties of virgin coconut oil,” JAOCS, J Am Oil Chem Soc., vol 86, no 4, pp 301–307, 2009 [2] F M Dayrit, O E Buenafe, E T Chainani, and I M De Vera, “Analysis of Monoglycerides, Diglycerides, Sterols, and Free Fatty Acids in Coconut (Cocos nucifera L.) 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FFA3 chứa chủ yếu acid béo tự mạch dài LCFA 85,86% 4.2 Kiến nghị Cần có nghiên cứu để: - Xác định chế kháng khuẩn MCFA thu nhận từ dầu VCO - Xác định liều lượng sử dụng MCFA để tránh tượng “gan... phóng đến 61,37% - Ở nhiệt độ 145 – 150oC áp suất 7,5mmHg, hỗn hợp acid béo tự FFA1 chứa chủ yếu MCFA 97,31% thu nhận FFA2 thu nhận áp suất với nhiệt độ cao 160 – 165oC, thành phần chủ yếu C12... án xác định được: - Đã chọn enzyme CRL thủy phân dầu VCO với tỉ lệ dầu/ đệm: 1/5 (w/w), tỉ lệ E/S: 5310U/g, pH nhiệt độ 40oC, sau 16 xúc tác đạt mức độ thủy phân lên đến 79,64% hàm lượng MCFA giải