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The antioxidant activities with respect to the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH)‐radical scavenging activity and reducing activity were assessed and compared for seven edible leafy vegetables (Enhydra fluctuans, Glinus oppositifolius, Amaranthus sp.1, Amaranthus sp.2, Amaranthus spinosus, Ipomoea aquatica and Corchorus sp.) widely consumed in India, especially West Bengal state. Phytochemical analysis of these vegetables revealed the presence of phenolics (gallic acid equivalents 2.87–61.85 mg/g), flavonoids (quercetin equivalents 2.75–406.98 mg/g) and tannins (tannic acid equivalents 7.39–32.52 mg/g). Two of the samples, E. fluctuans and Corchorus sp. exhibited remarkable DPPH radical scavenging activities (>70%) with significant IC50 values of 65.04 and 128.95 μg/mL, respectively. Extracts of these two species were also found to possess significant Fe3+‐reducing activities. The constituents of the extracts were separated by thin layer chromatography (TLC) and the positions of the antioxidative active fractions were determined using TLC bioautography followed by spraying with DPPH solution. The study suggested E. fluctuans and Corchorus sp. to be potential sources of antioxidative compounds. Practical Applications Concerns regarding the use of synthetic antioxidants as preservatives in the food industry, because of their toxicity and harmful health hazards, have resulted in the limitation of their usage in the food industry. This has necessitated urgent search for novel antioxidative compounds of natural origin for use as food supplements as well as preservatives in the food industry. Many of the fruits and vegetables consumed daily possess significant antioxidant activities and are good sources of natural antioxidative compounds. The selected seven leafy vegetables, all of which are widely consumed in India, were studied with respect to their relative antioxidative potentials. Accordingly, E. fluctuans followed by Corchorus sp. were found to have the best potential as sources of natural antioxidative compounds for uses in nutraceutical and food industry.

This review represents the studies performed on some beneficial mangrove plants such as Ceriops decandra, Xylocarpus granatum, Xylocarpus moluccensis, Excoecaria agallocha, Sarcolobus globosus, Sonneratia caseolaris and Acanthus ilicifolius from the Sundarban estuary spanning India and Bangladesh with regard to their biological activities and chemical investigations till date. Sundarban is the largest single chunk of mangrove forest in the world. The forest is a source of livelihood to numerous people of the region. Several of its plant species have very large applications in the traditional folk medicine; various parts of these plants are used by the local people as cure for various ailments. Despite such enormous potential, remarkably few reports are available on these species regarding their biological activities and the active principles responsible for such activities. Though some chemical studies have been made on the mangrove plants of this estuary, reports pertaining to their activity-structure relationship are few in number. An attempt has been made in this review to increase the awareness for the medicinal significance as well as conservation and utilization of these mangrove species as natural rich sources of novel bioactive agents.