Seminar khoa học của TS. Huỳnh Nguyễn Thanh Thảo,  và ThS. Ngô Văn Tài

Vào 14h00, ngày 25/10/2024 Viện IAST tổ chức buổi trao đổi học thuật tại Phòng họp Lầu 5 Thư viện với nội dung chi tiết như sau: 

TS. Huỳnh Nguyễn Thanh Thảo trình bày về "Electrochemical NaI-mediated one-pot synthesis of guanidines from isothiocyanates via tandem addition-guanylation"
Tóm tắt: 

In this study, we present an electrochemical approach for the synthesis of guanidines from isothiocyanates and amines in a single reaction vessel. This one-pot operation takes place in aqueous media, utilizing an undivided cell setup with NaI serving as both the electrolyte and mediator. The process involves the in situ generation of thiourea, followed by electrolytic guanylation with amines. Under ambient temperature conditions, we successfully demonstrated the formation of 30 different guanidine compounds, achieving yields ranging from fair to excellent. Furthermore, the synthesis method was able to carry in gram-scale experiment in good yield. This protocol stands out for its cost effectiveness, step-economical design, high tolerance towards various functional groups, and environmentally friendly reaction conditions.

ThS. Ngô Văn Tài trình bày về "Polyphenol-Modified Starches and Their Applications in the Food Industry: Recent Updates and Future Directions"
Tóm tắt:

Health problems associated with excess calories, such as diabetes and obesity, have become serious public issues worldwide. Innovative methods are needed to reduce food caloric impact without negatively affecting sensory properties. The interaction between starch and phenolic compounds has presented a positive impact on health and has been applied to various aspects of food. In particular, an interaction between polyphenols and starch is widely found in food systems and may endow foods with several unique properties and functional effects. This review summarizes knowledge of the interaction between polyphenols and starch accumulated over the past decade. It discusses changes in the physicochemical properties, in vitro digestibility, prebiotic properties, and antioxidant activity of the starch–polyphenol complex. It also reviews innovative methods of obtaining the complexes and their applications in the food industry. For a brief description, phenolic compounds interact with starch through covalent or non-covalent bonds. The smoothness of starch granules disappears after complexation, while the crystalline structure either remains unchanged or forms a new structure and/or V-type complex. Polyphenols influence starch swelling power, solubility, pasting, and thermal properties; however, research remains limited regarding their effects on oil absorption and freeze–thaw stability. The interaction between starch and polyphenolic compounds could promote health and nutritional value by reducing starch digestion rate and enhancing bioavailability; as such, this review might provide a theoretical basis for the development of novel functional foods for the prevention and control of hyperglycemia. Further establishing a comprehensive understanding of starch–polyphenol complexes could improve their application in the food industry.