In recent years, increasing consumption of herbal tea is a worldwide trend because of their refreshing taste, positive potential health effect, convenience, abundant resources and also cheaper in price. However, different maturity stages of plants being used as raw material could affect the antioxidant activity, colour and mineral content in herbal tea. Thus, this present study was aimed at determining antioxidant activity, colour and mineral content of herbal tea prepared from Cosmos caudatus (C. caudatus) leaves at three different maturity stages namely young, mature and old. All prepared herbal tea were analysed for total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), 2-2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, colour and mineral content. The results demonstrated that herbal tea prepared from young leaves had strong (p< 0.05) antioxidant activity compared to mature and old leaves for all assays tested. Pearson's correlation coefficient also revealed that TPC and TFC exhibited a strong positive correlation with reducing power but negatively correlated with DPPH scavenging activity indicating that these compounds are major contributors to the antioxidant activity. In fact, the darker (p< 0.05) colour of C. caudatus herbal tea prepared from young leaves relates to their higher antioxidant activity as compared to mature and old leaves. However, C. caudatus herbal tea prepared from old leaves showed significantly higher in mineral content compared to mature and young leaves. Hence, it can be concluded that, as maturity increased, antioxidant activity and colour in C. caudatus herbal tea decreased and vice-versa for mineral content.Keywords: herbal tea, Cosmos caudatus, maturity, antioxidant activity, colour, mineral content Abstrak Pada masa kini, peningkatan pengambilan teh herba menjadi ikutan terkini di seluruh dunia kerana rasa yang menyegarkan, mempunyai potensi yang positif terhadap kesihatan, sumber yang mudah didapati dan harga yang murah. Walaubagaimanapun, penggunaan sumber bahan mentah daripada tumbuh-tumbuhan pada peringkat kematangan yang berbeza mempengaruhi aktiviti antioksida, warna dan kandungan mineral di dalam teh herba. Oleh itu, kajian ini bertujuan untuk menentukan aktiviti antioksida, warna dan kandungan mineral di dalam teh herba yang dihasilkan daripada daun Cosmos caudatus (C. caudatus) pada tiga peringkat kematangan iaitu daun muda, matang dan tua. Semua sampel teh herba telah dianalisa untuk menentukan jumlah kandungan fenol (TPC), jumlah kandungan flavonoid (TFC), ujian penurunan ferik (FRAP), pemerangkapan radikal bebas 2-2-difenil-1-1pikrilhidrazil (DPPH), warna dan kandungan mineral. Keputusan menunjukkan bahawa, teh herba dihasilkan daripada daun muda mempunyai aktiviti antioksida yang tinggi (p< 0.05) berbanding dengan daun matang dan tua untuk semua asai diuji.
ISSN
-2506Dian Nashiela et al: ANTIOXIDANT ACTIVITY, COLOUR AND MINERAL CONTENT OF HERBAL TEA PREPARED FROM Cosmos caudatus LEAVES AT DIFFERENT M...