Nutritional Composition and Trace Elements Contents of Unfermented and Fermented Clinacanthus nutans L. Herbal Tea

Abstract

Clinacanthus nutans L. (locally known as ‘Sabah Snake Grass’) has been used traditionally to treat chronic diseases. However, there is insufficient information regarding the nutritional quality of the herbal. This study was conducted to evaluate the nutritional properties and trace elements contents of unfermented and fermented herbal teas developed from C. nutans leaves using different drying techniques (microwave- oven dried and freeze dried) in different infusion time (1, 2, 5, 10, 15 and 20 min). The proximate analysis were conducted according to AOAC’s standard methods, while, the colorimetric color of infusions were determined using HunterLab Color Meter. The trace elements in infusions were determined using Inductively Coupled Plasma-Optical Emission Spectrophotometric (ICP-OES) analysis. Among the C. nutans herbal teas, the freeze dried of unfermented herbal tea showed high ash (12.39 ± 0.39%) and fat (2.23 ± 0.10%) content, while, protein content was showed high in freeze dried of fermented herbal tea (23.15 ± 0.51%). Carbohydrate content was showed high in microwave-oven dried of unfermented herbal tea (63.40 ± 0.53%) with 3026.24 ± 28.23 kcal/kg of Metabolizable Energy (ME). For color infusion determination, C. nutans herbal teas displayed no significant difference (P >0.05) in color darkness as compared to commercial teas (L: 3.63 to 5.77). There were no significant differences between unfermented and fermented C. nutans herbal tea for its greenish (a: -2.69 to -1.20) and yellowish (b: 3.45 to 5.59) color infusion. Sixteen elements (Al, Ba, Be, Ca, Fe, In, K, Li, Mg, Mn, Na, Zn, Se, Sr, Tl and Si) were detected in the C. nutans and commercial dried leaves. Potassium (K), calcium (Ca), magnesium (Mg) and sodium (Na) were higher in C. nutans herbal infusions as compared to commercial teas infusions. Consumption of these herbal teas as dietary intake is able to overcome nutrients and minerals deficiency.