In silico evaluation of the potential for the rational use of garlic and onion crop residue extracts in cosmetics

The crop residue after harvesting onion (Allium cepa) and garlic (Allium sativum) is significant and it has a great potential for use in developing value-added products due to presence of a range of bioactive compounds. A potential of compounds found in the crop residue extracts to be used in cosmetics was evaluated using a range of in silico approaches, including evaluation of their interactions with selected skin target proteins (SIRT1, TGF-beta and elastase). Molecular docking results obtained using AutoDockVina revealed that the strongest interaction between small molecules in garlic/onion extracts was observed with TGF-beta protein (-10.8 Kcal/mol – rutin; -9.5 Kcal/mol - procyanidin A2; -9.2 Kcal/mol – quercetin, kaempferol, epigallocatechin, epicatechin and catechin). SIRT1 protein showed the best interaction with quercetin (-8.9 Kcal/mol) and kaempferol (-8.8 Kcal/mol), while the elastase interacted favorably only with procyanidin A2 (-8.3 Kcal/mol) and rutin (-7.9 Kcal/mol). Potential side effects on the skin of an individual molecules in extracts of garlic and onion were predicted using regulated databases for skin sensitization tests (Ambit, SkinSensDB, Danish QSAR Database, SkinDoctorCP). By screening the most active molecules through the mentioned skin sensitization tests, it was confirmed that rutin and procyanidin A2 are not irritating or corrosive to the skin, while SkinSensDB and SkinDoctorCP test reported quercetin, epicatechin and catechin as non-sensitizer. The obtained results indicate a significant potential for the use of crop residue extracts in the development of skincare products from the sustainable resources while addressing the issues of waste.