In vitro biological investigations on syzygium polyanthum cultivars

Syzygium polyanthum (Wight) popularly known as Serai Kayu and Serai Kayu Hutan is consumed in Peninsular Malaysia as Ulam and as a remedy to hypertension, diabetes, endometriosis, cancer and postpartum. The medicinal property of Serai Kayu and Serai Kayu Hutan was highlighted by the local traditional healers but not yet ascertained scientifically. Radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), α-glucosidase inhibition and antimicrobial assays were used to evaluates their biological activity. The ethanolic leaves extract of Serai Kayu Hutan showed a high antioxidant activity in terms of radical scavenging activities, reducing power and alpha-glucosidase inhibition activity at 2.34 μg/mL, 37.32 mmol/g and 19.6 μg/mL, respectively. All the tested parts of Serai Kayu and Serai Kayu Hutan exhibited activity against all the tested microorganisms with a moderate of zone inhibition of (4-28 mm) similar to the ampicillin used excepts in Listeria monocytogen no inhibition. Both the Serai Kayu and Serai Kayu Hutan exhibited the potentials to be utilized in the pharmaceutical and food industries and proved claim of traditional medical practitioners.