ปริมาณสารโพลีฟีนอลและฤทธิ์การต้านออกซิเดชั่นโดยรวม ของใบหม่อนและชาใบหม่อนจากบางแหล่งในประเทศไทย / รัตติยา สำราญสกุล = Total polyphenol content and antioxidant activity of mulberry leaves and mulberry tea from some sourecs in Thailand / Rattiya Samransakul
Leaves collected as tip, young and old ages of four varieties of mulberry namely Nakhonratchasima 60, Burirum 60, Khunpai and Noi were analyzed for flavonol, total polyphenol and total antioxidant activity. Each variety was grown in Nakhonratchasima, Udonthanee, Tak and Prae. Source, age and variety of mulberry leaves were the factors that have significant difference (p<=0.05) interaction for content of quercetin, kaempferol and total polyphenol. From Udonthani, the tip of Nakhonratchasima 60 had the highest content of quercetin and kaempferol (2,069.75 and 869.44 mg/100 g, respectively). And the tip of Burirum 60 variety had the highest content of total polyphenol (6,301.03 mg/100 g, gallic acid equivalents). In 5 types of mulberry tea, mulberry green tea by industrial process had the highest content of quercetin, kaempferol and total polyphenol. Quercetin and kaempferol contents in brew tea at 6 and 60 minute were significant difference (p<=0.05), whereas total polyphenol in extraction at 6, 12, 30 and 60 minute was no significant difference (p>=0.05). Total antioxidant activity in hot water extraction of mulberry green tea by industrial process had the highest values among the same tea but did not extracted with hot water before extraction in the same process and higher than the tip young and old ages of dry mulberry leaves with the same variety. These results confirm that mulberry leaves and mulberry tea are the good sources of quercetin, kaempferol and total polyphenol that have role of antioxidant and beneficial effects to preventive chronic disease in human health