Cannabis sativa L. is a controversial crop due to its high tetrahydrocannabinol content varieties; however, the hemp varieties get an increased interest. This paper describes (i) the main categories of phenolic compounds (flavonoids, stilbenoids and lignans) and terpenes (monoterpenes and sesquiterpenes) from C. sativa by-products and their biological activities and (ii) the main extraction techniques for their recovery. It includes not only common techniques such as conventional solvent extraction, and hydrodistillation, but also intensification and emerging techniques such as ultrasound-assisted extraction or supercritical CO2 extraction. The effect of the operating conditions on the yield and composition of these categories of phenolic compounds and terpenes was discussed. A thorough investigation of innovative extraction techniques is indeed crucial for the extraction of phenolic compounds and terpenes from cannabis toward a sustainable industrial valorization of the whole plant.
Chlorogenic acids are major phenolic constituents in many herbal medicines and exhibit various bioactivities that explain the growing interest in extracting chlorogenic acids from biomass. In this context, the present study aims to maximize 3-O-Caffeoylquinic acid (3-CQA) and 3,5-O-di-caffeoylquinic acid (3,5-diCQA) contents from forced witloof chicory roots and to analyze the extraction kinetic modelling. First, the solid–liquid ratio, ethanol concentration, extraction time and temperature were studied. The extraction conditions were optimized to maximize the extraction of these compounds. The maximum yields reached 5 ± 0.11 and 5.97 ± 0.30 mg/g dry matter (DM) for 3-O-Caffeoylquinic acid and 3,5-O-di-caffeoylquinic acid, respectively, in less than 6 min at 70 °C. Extraction with water as a solvent was assessed with the aim of proposing a second greener and less-expensive solvent. This extraction is very fast from 90 °C, with a maximum of 6.22 ± 0.18 mg/gDM of 3-O-Caffeoylquinic acid, and instantaneous for 3,5-O-di-caffeoylquinic acid with a maximum of 6.44 ± 0.59 mg/gDM. In the second step, response surface methodology was employed to optimize the ultrasound-assisted extraction of antioxidants. The higher antioxidant activities were found at temperatures from 40 °C and at percentages of ethanol in the range of 35–70%.
1 November 2021 in Food and Bioproducts Processing
Botrytis cinerea and Plasmopara viticola, the causal agents of grey mold and downy mildew, respectively, are two major grapevine pathogens whose control largely relies on synthetic fungicides, raising environmental and health concerns. Plant-derived secondary metabolites, particularly flavonoids involved in plant defense, represent promising sustainable alternatives. Among them, sakuranetin, a flavanone aglycone known for its antifungal activity in rice, remains poorly explored for grapevine protection. In this study, sakuranetin was purified from cherry branches (48 mg) and structurally characterized using UHPLC-ESI-QTOF-MS and NMR analyses. Its antifungal activity against B. cinerea and P. viticola was evaluated through in vitro, in vivo and in planta assays. For B. cinerea, our results showed a significant in vitro inhibition of mycelium growth, with EC50 values of 16.43 mg·L−1, while no protection of detached berries was observed. Against P. viticola, sakuranetin has no effect on the release of zoospores, but there is a total inhibition of spore germination at 1 mg·L−1 in vitro, confirmed in vivo on a foliar disc. In planta, no significant protection is observed at 25 mg·L−1, even if some targeted defense genes are induced. Further studies are needed to determine the best concentration of sakuranetin to use to manage B. cinerea and P. viticola in planta.
20 December 2025 in Food and Bioproducts Processing