The present study was an attempt to investigate the antiinflammatory activity of combined extracts (1:1mixture) of Syzygium cumini and Psidium guajava as well as to compare the invitro anti-inflammatory activity of them by the method of protein denaturation assay and Proteinase inhibitory activity. Both the plants selected belong to the family Myrtaceae. Ethanolic extract of shade dried leaves were used for the study. Diclofenac sodium was used as the standard drug. The result showed that at a concentration of 500 µg/ ml, the percentage inhibition of protein denaturation, by the combined ethanolic extract (1:1 mixture) of Syzygium cumini and Psidium guajava was 78.91, while for Diclofenac, the corresponding value was 89.36. The percentage inhibition of Proteinase , by the combined ethanolic extract (1:1 mixture) of Syzygium cumini and Psidium guajava at a concentration of 500 µg/ ml, was 86.46 and for Diclofenac the percentage inhibition of Proteinase was 90 .66 at the same concentration. The combined extract of the plants selected was found to be more effective than individual plant extracts against inflammation. The protein denaturation inhibition and Proteinase inhibition of the combined extract was found to be closer to that of the standard drug Diclofenac. On comparison of two plants Syzygium cumini was found to be more active against inflammation than Psidium guajava. As the 1:1 mixture of the ethanolic extract is found to be more active, the combination of the two plants can be used to formulate drugs for various inflammatory disorders.
Key words: Syzygium cumini ; Psidium guajava ; protein denaturation assay; Proteinase inhibitory activity.