**a.Brown seaweeds**

The ethyl acetate fraction of brown seaweed, *Ecklonia stolonifera* has been reported to possess a strong inhibitory effect on aldose reductase enzymes due to the presence of phlorotannins such as 7-phloroeckol and 2-phloroeckol in ethyl acetate fraction [47]. Similarly, phlorofucofuroeckol-A isolated from *Eisenia bicyclis* exhibited a potent inhibitory effect of aldose reductase enzyme (IC50: 6.22 *μ*M). They also confirmed the inhibitory effect of fucosterol in the rat lens. Carotenoids isolated from *Ecklonia stolonifera* exhibited potent inhibitory activity on aldose reductase enzyme (IC50: 18.94 *μ*M) compared to the standard positive control quercetin (IC50: 1.34 *μ*M). The presence of porphyrin derivatives (pheophytin-A and pheophorbide-A) in the dichloromethane fraction of *Saccharina japonica* caused excellent inhibitory effects on aldose reductase (AR) in rat lens [48]. Moreover, fucoxanthin isolated from *Undaria pinnatifida* and *Eisenia bicyclis* reported acting as a competitive inhibitor on the aldose reductase enzyme [49].
