Phytosterols extraction from hickory (Carya cathayensis Sarg.) husk with a green direct citric acid hydrolysis extraction method. (15th June 2020)

• Record Type: Journal Article
• Authors: Feng, Simin; Wang, Lei; Belwal, Tarun; Li, Li; Luo, Zisheng
• Is Part Of: Food chemistry. Volume 315(2020)
• Publication Date: 2020-06-15
• Subjects: Critic acid -- Phytosterols -- Hickory -- Response surface methodology; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.126217
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Citric acid, an organic acid, was used in direct hydrolysis extraction method. Both free and conjugated PSs were recovered from hickory husk by the new method. Conductivity could be a good index to indicate the extraction rate of PSs. Four PSs and one triterpenoid were firstly identified from hickory husk. The new method was more effective than traditional solvent extraction. Abstract: This study investigated the direct citric acid hydrolysis extraction method to optimize phytosterols extraction from hickory husk. Single factor experiments followed by a three-level three-factor Box-Behnken experiments were performed. The optimal extraction parameters were determined as: pH of 2.0, liquid-to-solid ratio of 17.12: 1 mL/g, and temperature of 55.81 °C. Practical experiments were carried out in triplicate, and subsequently yielded phytosterols of 912.452 ± 17.452 μg/g DW, in good consistence with the predicted extraction yield of 902.874 μg/g DW. The conductivity of the extract was also found to play effective role under direct citric acid hydrolysis and recorded 36.30 ± 1.08 μs/cm at optimum extraction condition. β-Sitosterol stigmasterol, campsterol, ergosterol and lupeol were detected as main PSs and triterpenoids in hickory husk using UPLC-Triple-TOF/MS. Finally, the comparison between direct hydrolysis extraction and traditional solvent extraction showed that this new method was more effective and eco-friendlier to extract both free and conjugated phytosterols.