Li Xiao-Jun, Guo Juan, Xu Yong-Ping, Li Shu-Ying, Li Na, Liu Qing-Ye
School of Chemistry and Chemical Engineering, North University of China, Taiyuan, China.
School of Bioengineering, Dalian University of Technology, Dalian, China.
PLoS One. 2025 May 7;20(5):e0322134. doi: 10.1371/journal.pone.0322134. eCollection 2025.
Hempseed threshing residues are rich in phytochemicals such as polyphenols and flavonoids. Phenolic and flavonoid compounds have been associated with antioxidant, antibacterial and anticancer activities. The re-use of the hempseed threshing residues as value-added materials is, not only cost-saving, but also environmentally beneficial. It is therefore important to develop an effective method for extraction of phenolic compounds and flavonoids from hempseed threshing residues.
In this investigation, the extraction of phenolic constituents and flavonoids from hempseed threshing residues using heat reflux extraction (HRE) were optimized through response surface methodology (RSM). Four HRE parameters to enhance the yield of crude extracts (CE), total phenolic content (TPC), and total flavonoids content (TFC) were evaluated. Additionally, the study evaluated the chemical compounds, antioxidant characteristics of the extracts, and the immune activity of the extracts was assessed by quantifying the levels of inflammatory cytokines, specifically IL-6, IL-10, and TNF-α.
The best extraction parameters were determined as: for the extraction time of 69.71 min, a liquid-solid proportion of 5.12:1, a particle size of 1150 µm, and an ethanol concentration of 69.60%. Under these optimized conditions, the yields for CE, TPC, and TFC were 4.74%, 27.54%, and 16.02% respectively. The data conformed well to multiple regression models, showing that these extraction parameters markedly influence the yields of CE, TPC, and TFC. Most of the compounds found may belong to the class of polyphenol and flavonoids. Cellular assays indicated that extracts from hempseed threshing residue notably reduced pro-inflammatory factors (TNF-α, IL-6) and increased anti-inflammatory factors (IL-10) in RAW 264.7 cells.
This research lays a theoretical foundation for extracting polyphenols and flavonoids from hempseed threshing residue and for the comprehensive assessment of antioxidant and immune-enhancing products. However, the antioxidant and immune activity of hempseed threshing residues extracts under physiological conditions in vivo, and the relevant mechanism should be further studied.
大麻籽脱粒残渣富含多酚和黄酮类等植物化学物质。酚类和黄酮类化合物具有抗氧化、抗菌和抗癌活性。将大麻籽脱粒残渣作为增值材料再利用，不仅节省成本，而且有利于环境。因此，开发一种从大麻籽脱粒残渣中提取酚类化合物和黄酮类化合物的有效方法具有重要意义。
在本研究中，采用响应面法（RSM）对热回流提取（HRE）大麻籽脱粒残渣中酚类成分和黄酮类化合物的工艺进行了优化。评估了四个热回流提取参数对粗提物（CE）产量、总酚含量（TPC）和总黄酮含量（TFC）的影响。此外，该研究还对提取物的化学成分、抗氧化特性进行了评估，并通过定量炎症细胞因子（特别是IL-6、IL-10和TNF-α）的水平来评估提取物的免疫活性。
确定的最佳提取参数为：提取时间69.71分钟，液固比5.12:1，粒径1150微米，乙醇浓度69.60%。在这些优化条件下，CE、TPC和TFC的产率分别为4.74%、27.54%和16.02%。数据与多元回归模型拟合良好，表明这些提取参数对CE、TPC和TFC的产率有显著影响。发现的大多数化合物可能属于多酚和黄酮类。细胞实验表明，大麻籽脱粒残渣提取物能显著降低RAW 264.7细胞中的促炎因子（TNF-α、IL-6），并增加抗炎因子（IL-10）。
本研究为从大麻籽脱粒残渣中提取多酚和黄酮类化合物以及对抗氧化和免疫增强产品进行综合评估奠定了理论基础。然而，大麻籽脱粒残渣提取物在体内生理条件下的抗氧化和免疫活性及其相关机制仍需进一步研究。
