A novel process for the aqueous extraction of oil from <i>Camellia oleifera</i> seed and its antioxidant activity

Abstract

Aqueous extraction is a promising green alternative to hexane extraction. This study used a salt effect-aided aqueous extraction process (AEP-SE) for extracting <i>Camellia oleifera</i> seed oil (COSO) to improve oil extractability and avoid emulsification in the aqueous system. The highest oil extractability rate of 88.8% was obtained under 1.48 mol L^–1 sodium carbonate, a solution-to-flour ratio of 3.85, and 3.23h of extraction time with the quality of the aqueous system-extracted oil being similar to those of a commercial sample of COSO and hexane-extracted oil in terms of color, iodine value and saponifcation value, although its moisture content was higher. Furthermore, the free fatty acid content of the aqueous system-extracted oil was lower than that of the solvent-extracted oil. The values of the inibihitory concentration at 50% of oil obtained by AEP-SE and organic solvent extraction as measured by DPPH scavenging activity essay, were 2.27 mg/mL and 3.31 mg/mL. AEP-SE is therefore a promising environmentally friendly method for the large-scale preparation of COSO.<br><br>La extracción acuosa es una alternativa verde muy prometedora a la extracción con hexano. En este estudio se utilizó como ayuda en el proceso de extracción acuosa (AEP-SE) el efecto de una sal para la extracción de aceite de semilla de <i>Camellia oleifera</i> (COSO) para mejorar la extractabilidad y evitar la formación de emulsiones en el sistema acuoso. La mayor velocidad de extracción de aceite, 88,8%, se obtuvo con una concentración de carbonato de sodio de 1,48 mol L^–1, una relación de solución a la harina de 3,85, y 3.23h de tiempo de extracción, con una calidad del aceite extraído con el sistema acuoso similares a los de una muestra comercial de COSO extraida con hexano, en términos de índice de yodo, de color, y de índice de saponificación, aunque su contenido en humedad fue mayor. Además, el contenido de acidez libre del aceite extraido con el sistema acuoso fué menor que la del aceite extraído con disolvente. Los valores de la concentración inibihitoria al 50% del aceite obtenido por el AEP-SE y extracción con disolvente orgánico, medido por el ensayo de DPPH actividad de barrido, fueron 2,27 mg mL_–1 y 3,31 mg mL_–1. Por lo tanto, AEP-SE es un método favorable al medio ambiente, prometedor para la preparación a gran escala de COSO

Physiochemical characteristics, fatty acid profile and tocopherol composition of the oil from <em>Camellia oleifera</em> Abel cultivated in Henan, China

“…The fatty acid composition of the C. oleifera oils in our study was comparable to those of the oils from the C. oleifera seeds cultivated in the other provinces of China reported by previous researchers (p<0.05) (Cao et al, 2017;Cheng et al, 2010;Jiang et al, 2010;Xi et al, 2002;Yang, 2010;Yao et al, 2011;Yu et al, 2013;Yuan et al, 2013). The oils from the C. oleifera seeds cultivated in Jinhua (Zhejiang, China) consisted of 8.10% palmitic, 0.10% palmitoleic, 1.90% stearic, 80.90% oleic, 8.10% linoleic acid, 0.30% linolenic, 0.60% eicosenoic acid, and UFAs were 90.00% (Cao et al, 2017).…”

“…oil from the seed cultivated in Hunan (China) were 180.5 mg KOH/g and 81.5 g I 2 /100g, respectively (Yun et al, 2011). The IV and SV of the C. oleifera oil from the seed cultivated in Fujian (China) were 85±2 g I 2 /100g and 195±1 mg KOH/g, respectively (Yu et al, 2013).…”

“…These oils consisted of 7.16-8.87% palmitic, 1.42-2.78% stearic, 76.72-83.18% oleic, 6.59-9.71% linoleic, 0-1.18% linolenic, and 0-0.79% arachidic (Yao et al, 2011). The fatty acid composition of the oil from the C. oleifera seeds cultivated in Fujian (China) was 10.20% palmitic, 1.70% stearic, 77.84% oleic, 8.30% linoleic, 0.37% linolenic, 0.59% arachidic (Yu et al, 2013). Yuan et al (2013) evaluated the fatty acid composition of 132 C. oleifera oils from the seeds collected from several provinces of China in 2009.…”

“…The kernel of C. oleifera seed is rich in oil/lipid and polysaccharide (Yu et al, 2013). The oil/lipid content of the C. oleifera seed and fatty acid composition of its oil are affected by the variety, cultivated soil and surrounding climate (Guo et al, 2013;Yao et al, 2011;Yu et al, 1999).…”

“…The oil/lipid content of the C. oleifera seed and fatty acid composition of its oil are affected by the variety, cultivated soil and surrounding climate (Guo et al, 2013;Yao et al, 2011;Yu et al, 1999). The research is mainly focused on the oil content of C. oleifera seeds, the iodine value, saponification value and refractive index and the fatty acid composition of the oils from these seeds cultivated in Hunan, Jiangxi, Guangxi, Zhejiang, Yunnan, Sichuan, Guizhou, Guangdong and Hubei of China have been evaluated Chen et al, 2012;Cheng et al, 2010;Dong et al, 2012;Guo et al, 2008;Guo et al, 2013;Ma et al, 2011;Xi et al, 2006;Yao et al, 2011;Yu et al, 2013;Yuan et al, 2013). Few reports on the minor components (such as Vitamin E and carotene) in C. oleifera oil are available.…”