Bioactives from Crude Rice Bran Oils Extracted Using Green Technology

Abstract

Crude rice bran oils from different rice cultivars and extraction methods bear different contents of nutraceuticals. The health benefits of lowering cholesterol activity of rice bran oil being confirmed by many reports are partly attributed to non-nutrient nutraceuticals, especially γ-oryzanol, phytosterols, and policosanols. As the world has been facing the global warming crisis, green extraction technology is gaining attention from many sectors. The current study aims to compare the nutraceutical composition with respect to γ-oryzanol, phytosterol, and policosanol content as well as the antioxidant properties of crude rice bran oils extracted from white and red rice bran using three green technologies, comparing with conventional hexane extraction. The data show that the traditional solvent extraction gave the highest oil yield percentage (26%), but it was not significantly different from subcritical liquefied dimethyl ether extraction (24.6%). Subcritical liquefied dimethyl ether extraction gave higher oil yield than supercritical CO2 extraction (15.5–16.2%). The crude rice bran oil extracted using subcritical liquefied dimethyl ether extraction produced the highest total phenolic contents and antioxidant activities. The highest γ-oryzanol content of the crude rice bran oil was found in oil extracted by conventional cold press (1370.43 mg/100 g). The γ-oryzanol content of the oil obtained via subcritical liquefied dimethyl ether extraction was high (1213.64 mg/100 g) compared with supercritical CO2 extraction. The red rice bran yielded the crude rice bran oil with the highest total phytosterol content compared with the white bran, and the oil from red rice bran extracted with subcritical liquefied dimethyl ether generated the highest total phytosterol content (1784.17 mg/100 g). The highest policosanol content (274.40 mg/100 g) was also found in oil obtained via subcritical liquefied dimethyl ether extraction.

Encapsulation of turmeric extract and rice bran oil in alginate hydrogel microcapsules

“…Data presented in Table 1. showed that RBO contained 1.84% γ-Oryzanol, which is in the range reported by (Wongwaiwech et al, 2023 andLloyd et al, 2000), who reported that the γ-Oryzanol content of RBO ranged from 0.74 to 2.9%. Plant phenolic compounds play a major role as free radical scavengers and are essential components that contribute to functional quality, color, and flavor (Tanvir et al, 2015).…”

“…Meanwhile, the RBO content of total phenol content recorded 589.75 mg GAE/100g. Previous research illustrated that the total phenol con-tent of the RBO samples ranged between 400.39 and 663.00 mg GAE/100g (Wongwaiwech et al, 2023;Mingyai et al, 2017). The DPPH-free radicalscavenging activity of the aqueous extracts of turmeric and rice bran oil was investigated to determine their antioxidant properties.…”

Normal fat intake with high MUFA content and an appropriate SFA/MUFA/PUFA ratio improved the health of rats

“…Furthermore, the oils contain different amounts of micronutrients: red palm oil is rich in β-carotene and is the main source of β-carotene in the BO, whereas rice oil is rich in γ-oryzanol and phytosterols and is the main source of γ-oryzanol in the BO. [14,22] OO is high in polyphenols and squalene, whereas SO has the highest vitamin E content, mainly in the form of gamma-tocopherol. [23,24] Thus, these oils have unique health effects; however, the specific effects of these oils at particular intake levels remain unknown.…”

Phytosterols in rice bran and their health benefits

“…Nevertheless, traditional methods exhibit shortcomings in terms of time consumption, energy inefficiency, limited economic viability, and environmental contamination ( 32 ). Thus, researchers have reported novel techniques for extracting phytosterols, such as ultrasonication assisted extraction ( 33 ), supercritical fluid extraction (SFE) ( 34 ), subcritical extraction (SUBE) ( 35 ), and ohmic heating-aided mechanical extraction ( 36 ). The yields of γ-glutamin from rice bran obtained by SE, SFE, and SUBE and the concentrations in the extracts are presented in Table 1 .…”