Antioxidant and antibacterial effects of medicinal plants and their stick-type medicinal concentrated beverages

Abstract

Nine medicinal plants and their stick-type medicinal concentrated beverages (SMCB-I and SMCB-II) with different combination ratio were evaluated on antioxidant, nitric oxide (NO) inhibitory, and antibacterial effects against pathogenic bacteria involved in respiratory system illnesses. Antioxidant activity was high in Syzygium aromaticum, Pueraria lobata, Plantago asiatica, and Kalopanax pictus which have higher contents of total phenolics and total flavonoids. The NO inhibitory activity was high in Syzygium aromaticum, Plantago asiatica, and Glycyrrhiza uralensis. Syzygium aromaticum, Plantago asiatica, Kalopanax pictus and Glycyrrhiza uralensis showed higher antibacterial activity than the other five medicinal plants against Staphylococcus aureus, Corynebacterium diphtheriae, and Mycobacterium sp. SMCB-II exhibited higher antioxidant, NO inhibitory, and antibacterial effects than SMCB-I, since Syzygium aromaticum, Pueraria lobata, and Kalopanax pictus were only used for the production of SMCB-II. The SMCBs would be expected to contribute to an easy-to-carry, easy-to-consume, and high value-added health beverage for the modern people.

Keywords: Antibacterial; Antioxidant; Medicinal plants; Nitric oxide; Stick-type medicinal concentrated beverage.

Fig. 1

The effect of stick-type medicinal concentrated beverages and medicinal plant extracts on LPS-induced NO production in RAW 264.7 cells; (A) stick-type medicinal concentrated beverages; (B) medicinal plant extracts. ^*Significant difference between LPS and each medicinal plants (***p < 0.001; **p < 0.01; *p < 0.05). ^a–eMeans with different letters on the bars are significant different among the medicinal plants or among the medicinal concentrated extract (p < 0.05)