The comparison of krill oil extracted through ethanol–hexane method and subcritical method

Abstract

This study aimed to develop a safe method EH (ethanol–hexane) to extract two kinds of krill oil (KO) simultaneously and analyze their composition. Meanwhile, subcritical butane and subcritical butane‐dimethyl ether extraction were used to extract KO for analysis comparison. Folch method was used to extract total lipids. When the volume ratio of ethanol to hexane is 4:6, the separation effect of ethanol layer and hexane layer is best. At this condition, the EH method yielded similar amount of lipids (up to 97. 72% of total lipids) with subcritical butane extraction method (97.60%). The recovery rate of ethanol and hexane was 83.6% and 86.86%, respectively. KO in hexane layer and extracted by the subcritical butane method are abundant in astaxanthin (910 and 940 mg/kg respectively), while KO in the ethanol layer had the highest phospholipid (PL) content (47.34%), n−3 polyunsaturated fatty acids (PUFA) content (45.51%), and the lowest fluorine content (11.17 μg/g), making it a potential candidate in the nutraceutical and antioxidant industry.

Comparison of different solvents for extraction of oils from by‐products of shrimps Penaeus vannamei and Procambarus clarkia

“…Therefore, this combination solvent was a suitable solvent for simultaneous extraction of polar and nonpolar lipids from shrimp by-products. Likewise, the above finding was also confirmed by other studies (Sun et al, 2019;Yin et al, 2016). For example, Yin et al, (2018) reported that, compared with krill oils extracted with hexane, oils extracted with the mixed solvent of ethanol and n-hexane…”

“…Yin et al, (2018) also reported that krill oils recovered by ethanol and mixed solvents of ethanol and hexane contained a larger proportion of PUFA than that extracted by hexane. It has been widely accepted that the PL fraction contained more PUFAs than TAG fraction in krill oils (Gigliotti et al, 2011;Sun et al, 2019;Xie et al, 2019). The results of phospholipid class composition indicated that, compared with oils extracted with hexane and acetone, those extracted with the mixture of ethanol and hexane (4:1, v/v) and ethanol contained more PL fraction (Table 1), which maybe lead to the higher PUFA levels.…”

“…For the two raw materials, compared with oils recovered using hexane, those recovered using ethanol and mixed solvents of ethanol and n-hexane (4:1, v:v) contained relatively higher amount of PUFA, such as DHA and EPA. Sun et al, (2019) reported that PUFA content in krill oil extracted with ethanol was significantly higher than that extracted with hexane. Yin et al, (2018) also reported that krill oils recovered by ethanol and mixed solvents of ethanol and hexane contained a larger proportion of PUFA than that extracted by hexane.…”

Chemical Composition and Evaluation of the α‐Glucosidase Inhibitory and Cytotoxic Properties of Marine Algae Ulva intestinalis, Halimeda macroloba, and Sargassum ilicifolium

“…Lipid extraction was performed on the finely powdered seaweed samples according to slight modifications to the method adopted by Sun et al 2019 [ 17 ]. Briefly, approximately 0.5 g of freeze-dried seaweed powder was homogenised (Branson CPX2800H Ultrasonic Cleaner, USA) with 20 mL of chloroform: methanol (2 : 1 v/v) for 5 min.…”

Advances in Technologies for Highly Active Omega-3 Fatty Acids from Krill Oil: Clinical Applications

“…This compound is responsible for the typical dark red color of krill oil and is endowed with potent antioxidant properties, even more than other carotenoids such as zeaxanthin, lutein, canthaxanthin, β-carotene and α-tocopherol [37]. Generally, the amount of astaxanthin in krill oil ranges from 40 to 5000 mg/kg and depends on intrinsic features of krill (for example raw material, krill species) or can vary due to extraction and analysis methods [38]. Indeed, as reported in the below section, a high concentration of astaxanthin can be achieved by using acetone as the extraction solvent [39].…”