The principal component analysis of antioxidant activities of Songgak, a traditional herbal drink in West Nusa Tenggara, Indonesia

Songgak is a traditional herbal tea of the Sasak Tribe in Lombok Island, Indonesia,-formulated to strengthen people's stamina. Songgak is composed of seven kinds of roasted-spices: Piper nigrum L., Coriandrum sativum L., Piper retrofractum Vahl, Myristica-fragrans Houtt, Syzygium aromaticum, Elaeocarpus grandiflorus, and Helicteres isora. This study aimed to assess the benefits of Songgak and its constituent spices by evaluating-their antioxidant activities, total phenolic content (TPC) and flavonoid content (TPC). Antioxidant activity tests were performed on the water extract of Songgak, ethanolic-extract of Songgak, and ethanolic extract of seven spices of Songgak including 2,2′diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, Trolox equivalent antioxidant-capacity (TEAC), and ferric reducing antioxidant power (FRAP) assay. The antioxidant-activity using DPPH method showed that the water extract of Songgak has a strong-categorisation of antioxidant activity with DPPH IC50 value of 63.78±4.29 µg/mL. The-constituent species of Songgak with the strongest antioxidant activity was S. aromaticum. Total phenolic content (TPC) and total flavonoid content (TFC) of Songgak tea were-26.85±4.29 mg GAE/g and 6.99±0.29 mg RE/gram, respectively. The correlation between-TPC, TFC, and antioxidant activities was determined using principal component analysis-(PCA). The loading plot showed that TPC and TFC were strongly correlated with the-antioxidant activity (FRAP method) of Songgak tea and its constituent spices. These-results revealed that the presence of flavonoid and phenolic compounds in the seven-herbal medicinal plants were responsible for the antioxidant properties of Songgak as a-healthy herbal drink. Therefore, consuming Songgak every day can be beneficial for-preventing various diseases involving free radicals.