In this study, an efficient and eco-friendly method was developed for continuous liquid–liquid extraction of lutein from microalgaeChlorella vulgaris. By employing a limonene-based biphasic liquid system, high-purity lutein was successfully obtained from the crude extract in a single run via centrifugal partition chromatography (CPC). Evaluation and optimization results demonstrated that limonene could effectively serve as a replacement forn-hexane as the solvent system for lutein extraction, exhibiting natural renewability and minimal environmental impact. Furthermore, the elution–extrusion operation mode was employed to fully exploit the liquid nature of the stationary phase in the extraction process, allowing for continuous sampling and separation without interruption. This proposed protocol offers a sustainable and environmentally friendly alternative for extracting valuable ingredients from microalgae biomass, demonstrating its potential as a scalable solution for producing lutein-enriched ingredients applicable to functional foods and nutraceuticals.
Orange peel waste (OPW) and sewage sludge (SS) valorization for volatile fatty acids (VFAs) production from anaerobic co-fermentation are attractive and feasible. The highest VFAs reached 11996.3 mg COD/L within 10 d at the mass ratio (TS/TS) of 1:1, which was approximately 30-fold of that in sole SS fermentation. The OPW provided plenty of organic substrates and facilitated the fermentation processes by disintegrating SS structure and inhibiting methanogenesis due to the abundant limonene. Also, the OPW feeds reshaped the microbial community and enriched fermentative bacteria, especially those saccharolytic ones ( i.e. Prevotella-7 ). The key genes involved in membrane transport ( i.e. ptsG ), glycolysis ( i.e. pgk ), pyruvate metabolism ( i.e. ace ), and fatty acid biosynthesis ( i.e. accA ), which are associated with VFAs biosynthesis, were up-regulated in OPW/SS reactors. Overall, it was the increase in bioavailable organic matter and functional microorganisms, and the simultaneous enhancement of metabolic activity that improved the efficient VFAs production.
Jiahuan Xu,Lijin Peng,Jianbo Chu,Jing Shi,Qinmin Cui,Qiyuan Shi
This work aims to resolve the environmental pollution caused by petroleum ether in the production of pure nuciferine from lotus leaf by applying bio-based solvent (D-limonene) and green solvent (ethyl acetate). Some obvious advantages were observed, over 97% of nuciferine could be extracted by vortex assisted two-phase solvent extraction based on multi-stage strategy (MS-VTSE), over 90% of nuciferine could be recovered by solid phase extraction (SPE), and over 97% of nuciferine could be obtained by pH-dependent liquid-liquid extraction (pH-LLE). It follows that the newly developed method can not only avoid the use of petroleum ether, but also increase the yield of the whole process by 14% (57%) in comparing with the result of the original one (50%) reported in our previous study. As D-limonene could by recycled conveniently, solvents replacement has little effect on the cost of production. In a word, the newly proposed method has advantages in environmental protection and solvent saving, thus, is fitting for the green and low-cost production of pure nuciferine from lotus leaf.