Microwave-assisted vs. conventional hydrodistillation of Corchorus olitorius: a chemical and enzyme inhibition study

Abstract

Background: Corchorus olitorius L. (Malvaceae) is a green leafy vegetable widely consumed in the Middle East and valued for its rich nutritional content. Its essential oils, an important class of secondary metabolites, are of growing interest for potential use in cosmetics and fragrance industries due to their bioactive properties. Methods: Leaves of C. olitorius cultivated in Egypt were extracted using microwave-assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD). The oils were analyzed by gas chromatography-mass spectrometry (GC-MS) to characterize their chemical profiles. In vitro assays were conducted to evaluate their anti-elastase and anti-collagenase activities, and in silico studies were performed to predict the pharmacokinetic and pharmacodynamic properties of major constituents. Results: GC-MS analysis showed that aldehydes, alkanes, fatty alcohols, fatty acids, and their derivatives were the predominant compound classes in both oils. Notably, oxygenated diterpenes (11.22%) were present exclusively in the MAHD oil, while triterpenoids (16.37%) were found only in the HD oil. The MAHD oil demonstrated stronger In vitro anti-elastase (IC<inf>50</inf> = 42.5 μg/mL) and anti-collagenase (IC<inf>50</inf> = 131.5 μg/mL) activities compared to the HD oil (IC<inf>50</inf> = 66.7 and 206.8 μg/mL, respectively), reflecting an approximate 36.3% improvement in elastase inhibition and 36.4% improvement in collagenase inhibition. In silico docking indicated that the triterpenoid β-amyrin acetate showed the highest predicted binding affinity for porcine pancreatic elastase (PDB ID: 6QEO, ∆G = −8.1 kcal/mol) and collagenase (PDB ID: 456C, ∆G = −9.1 kcal/mol) among the major compounds analyzed. Conclusion: These findings demonstrate that MAHD is a greener and more efficient extraction method, yielding oil with enhanced enzyme inhibitory activity compared to conventional HD. The promising anti-elastase and anti-collagenase properties suggest that C. olitorius MAHD oil could serve as a potential candidate for anti-aging cosmetic formulations, following further validation.