Evaluation of antioxidant capacity of Aidia borneensis leaf infusion, an endemic plant in Brunei Darussalam

Abstract

We investigated the total antioxidant capacity of Aidia borneensis leaf infusion, a Bornean endemic plant, which is traditionally consumed as a home-remedy beverage in Brunei Darussalam. The antioxidant capacity of the infusion of A. borneensis leaves was evaluated by 2,2-diphenyl-1-picryhydrazyl (DPPH) radical-scavenging ability. We found that the infusion shows a relatively high antioxidant capacity, and it was attributed to its high phenolic, flavonoid, and flavanol contents which were evaluated by Folin-Ciocalteu reagent, colorimetric assay, and aluminum chloride colorimetric method, respectively. By comparing its total antioxidant capacity, we estimated that the infusion of A. borneensis leaves is in the middle rank among twelve different commercially available Camellia sinensis teas. Our findings would have significant implications on A. borneensis products from Brunei Darussalam and on the feasibility of establishing this new beverage among the commercially available conventional C. sinensis and herbal teas.

The total antioxidant capacity and fluorescence imaging of selected plant leaves commonly consumed in Brunei Darussalam

“…This indicates that leaves of the plants in this study, particularly A. borneensis and A. occidentale are potential sources of natural antioxidants. We should note that the total antioxidant capacity of the infusions of the C. asiatica, A. borneensis, and A. occidentale leaves is abruptly increased either with higher brewing temperature or longer brewing time [23]. Similar tendency has also been observed for C. sinensis black and green teas [24].…”

“…Similar tendency has also been observed for C. sinensis black and green teas [24]. However, in our previous study, we have demonstrated that more than 90% of the total antioxidant capacity was achieved at brewing temperature of 60°C, for the first 3 min infusion time [23]. The total antioxidant capacity was slowly increased with infusion time [23].…”

“…As shown in Figure 1, the IC50 of C. asiatica, A. borneensis, and A. occidentale dried young and matured leaves (0.5 g) infused in 25 ml water-methanol (20:80) was measured to be within 65 to 890 ppm, equivalent to 310 to 4124 mg gallic acid per 100 g dry sample. As for comparison, we have reported that IC50 of commercial teas from different brands was in the range of 143 to 4078 ppm [23]. This indicates that leaves of the plants in this study, particularly A. borneensis and A. occidentale are potential sources of natural antioxidants.…”

“…However, in our previous study, we have demonstrated that more than 90% of the total antioxidant capacity was achieved at brewing temperature of 60°C, for the first 3 min infusion time [23]. The total antioxidant capacity was slowly increased with infusion time [23]. Efficient releases and diffusions of the phytochemicals and polyphenols from the leaves into the brewing solution due most probably to openings, interstices, denaturation, or disruption of the plant cells.…”

Phytochemical analysis, antimicrobial and antioxidant activities of Aidia borneensis leaf extracts

“…To the best of our knowledge, the scientific evaluation of the pharmacological properties of this plant has not been reported yet, except for its antioxidant property. It was found that the leaf infusion of this plant showed a relatively high antioxidant activity, which could be attributed to its high phenolic, flavonoid, and flavanol contents [5].…”