Optimization of the pulse electric field assisted extraction of black rice grain for antioxidant and sirtuin1 enzyme stimulation activities

Abstract

Cyanidin-3-glucoside (C3G) and peonidin-3-glucoside (P3G) in black rice grain (BRG) demonstrate many beneficial health effects, including antioxidant and anti-aging properties. This research aimed to study on pulsed electric field assisted water extraction (PEF-AWE) on BRG using pre-treatment technique, which was determined for enhanced yields of C3G and P3G, antioxidant and sirtuin1 enzyme stimulation activities. The effects of operating parameters for PEF-AWE (intensity of electric field, X1: 3–5 kV/cm, number of pulse, X2: 1000–3000 pulse and BRG/water ratio, X3: 0.1–0.5 g/mL) were determined using regression analysis and optimized PEF-AWE condition using the response surface methodology. Regression models showed the intensity of electric field and BRG/water ratio were the strong influence parameters significantly on C3G (p < 0.01). The results highlighted optimized conditions of PEF-AWE followed by 5 kV/cm, 3000 pulse and 0.5 g/mL leading to achieve higher C3G (92.59 ± 4.79 mg/g) and P3G (4.59 ± 0.27 mg/g) than no pre-treatment by PEF process, approximately 60%. Additionally, PEF extracts of BRG can modulate the ability of surtuin1 enzyme to deacetylate substrate proteins (26.78 ± 0.50 FIR). Thus, PEF-AWE can be applied to produce BRG extract as natural antioxidant compound and functional ingredient.

Pulsed electric field‐assisted extraction of mushroom ß‐glucan from Pleurotus pulmonarius by‐product and study of prebiotic properties

“…The PEF machine used in this study was similar to that used in research of Salee et al . (2022). The extraction chamber had a rectangular shape of 4 × 13 cm, with electrodes spaced 2 cm apart.…”

“…In comparison, hot water extraction was performed by mixing the powder with distilled water at a ratio of 1:30 and subsequent heating at 100 °C for 6 h (Smiderle et al, 2013). The PEF machine used in this study was similar to that used in research of Salee et al (2022). The extraction chamber had a rectangular shape of 4 × 13 cm, with electrodes spaced 2 cm apart.…”

Comparison of pulse electric field, microwave and ultrasonic pretreatment prior to black rice extraction on antioxidant and sirtuin1 enzyme stimulating activities

“…The surtuin1 Activity Assa Kit (Fluorometric) of Abcam (ab156065) was used to evaluate the surtuin1 enzyme-stimulating activity of extract in accordance with the instructions from manufacturer. The in vitro assay of surtuin1 enzyme-stimulating activity of extract was examined according to Salee et al (2022). The mixture solution of water HPLC-grade (25 µL), surtuin1 assay buffer (5 µL), fluoro-substrate peptide (5 µL) and NAD (+)-dependent histone deacetylase (5 µL) was added and mixed gently to the wells of a microtiter plate.…”

“…Black rice (Oryza sativa L.) is a type of pigmented rice that contains significant amounts of anthocyanins in the bran layer, and is regarded as an effective health-promoting functional food. Anthocyanin from black rice was identified by cyanidin-3-glucoside (C3G) and peonidin-3-glucoside (P3G) (Salee et al, 2022) which demonstrated scientifically proven health benefits, as well as promoted immune responses in leukemia (Fan et al, 2017), anti-diabetes and hyperlipidemia (Yang et al, 2011;Zhang et al, 2013) and cholesterol and lipid metabolism. Colored rice could affect the expansion of life-span by reducing the reactive oxygen species (ROS) via Sir2-dependent signaling pathways, with human homologs of NAD-dependent deacetylase sirtuin-1 (surtuin1) (Sunthonkun et al, 2019).…”

“…As a result of their lower toxicity compared to that of methanol and hydrochloric acid, ethanol and water acidified with acetic acid and organic acids were extensively used as solvents for anthocyanins and other bioactive chemicals extraction from black rice (Escribano-Bailón et al, 2004). In addition, water was considered as an optional new and environmentally friendly solvent for the extraction of bioactive compounds, as well as anthocyanins from black rice (He et al, 2017;Prommachart et al, 2020;Salee et al, 2022). Furthermore, extraction procedures that use water as a solvent were linked to an increase in environmental and health concerns (Carpentieri et al, 2021).…”