Background. Dental/oral diseases are one of the significant public health problems globally. Herbal medicines for managing oral diseases are considered an effective alternative to synthetic compounds due to their lower side effect. Azadirachta indica, Terminalia chebula, Camellia sinensis, and Piper nigrum are used to control and prevent oral inflammations in dentistry. In this study, we have evaluated the protease inhibition activity of these plant extracts, and further, the binding mode of the active ingredient of these plants with trypsin was studied using molecular docking. Methods. In this study, protease inhibition activity was carried out using aqueous extracts of the plant parts such as Azadirachta indica (neem) twig, Terminalia chebula (Haritaki) fruit, Camellia sinensis (green tea) powder, and Piper nigrum (kali miri) seed. Next, to explore the binding mode of active ingredients azadirachtin, chebuligenic acid, catechin, and piperine with trypsin, we employed a molecular docking study using AutoDock4.2. Results. The results revealed that the Azadirachta indica plant extract showed an IC50 value of 96.19 μg mL-1, Camellia sinensis IC50 value of 188.50 μg mL-1, Piper nigrum IC50 value of 371.20 μg mL-1, and Terminalia chebula IC50 value of 639.48 μg mL-1, when compared with standard drug diclofenac sodium, had IC50 value 93.00 μg mL-1. Further, the docking result reveals that all the main active ingredients of these plants have significant binding affinity and prefer the same binding pocket of trypsin. Conclusion. Hence, our results show the importance of traditional plants Azadirachta indica, Terminalia chebula, green tea, and Piper nigrum to control oral disease conditions. As they show significant protease inhibition activity, hence, the active ingredient could act as a potential anti-inflammatory agent and further help to prevent or control oral disease conditions such as gingivitis and periodontitis.
