The analysis of nutritional value, total phenolic and flavonoid contents, and antioxidant activities from the ethanolic extracts of the roasted broken brown rice powder

Abstract

The objective of this study was to determine the nutritional value, total phenolic and flavonoid contents, and antioxidant activities of the roasted broken brown rice powder. The roasted broken brown rice powder was dried at 60 °C for 3 h in a hot air oven and extracted with absolute ethanol by using ultrasonic technique. Then, the sample was filtered to separate the residue and mixture solution and dried to remove the solvent by rotary evaporator for obtaining the ethanolic crude extract. Finally, the crude extract was collected and determined proximate composition, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant capacity. The results revealed that the percentage crude extract of the extraction yield was 0.47% by weight with crude carbohydrate (74.47% w w−1), crude protein (8.11% w w−1), and fat (0.05% w w−1), respectively. The TPC and TFC were found at an average of 20.40 ± 0.37 mg GAE g−1 crude extract and 4.58 ± 0.19 mg QE g−1 crude extract, respectively. Moreover, the sample has highly efficient antioxidants activity similar to a standard Trolox solution. Therefore, it was reasonably concluded that the roasted broken brown rice powder product was rich in beneficial nutrients for the health effects and represented adding value to a by–product of rice production.

Evaluation of the Nutritional, Minerals, and Antioxidant Potential of Roselle (Hibiscus sabdariffa Linn.) Seeds from Roi Et Province in the Northeastern Region of Thailand

“…While antioxidant compounds generally contain a phenolic group, it was typically analyzed with the Folin-Ciocalteu reagent and used gallic acid as a reference standard. This method uses the UV-vis technique to analyze the simple, convenient, economical, highly accurate, and transparent results of the experiment [21][22][23][24].…”

“…This phenomenon can explain that various factors might strongly influence the antioxidant activities of roselle seeds crude extract, such as antioxidant compound concentration in the example, temperature, pH value, and plant growth process in different areas. All these possible reasons directly affected on synthesis process of important plant substrates, especially bioactive compounds [5,20,22,25]. For this reason, roselle seeds were another whole cereal source rich in beneficial nutrients and high in bioactive compounds, especially antioxidants that were important for consumers.…”