Two important biologically active compounds were isolated from Mallotus philippensis. The isolated compounds were characterized using spectroanalytical techniques and found to be bergenin (1) and 11-O-galloylbergenin (2). The in vitro antioxidant and antiplasmodial activities of the isolated compounds were determined. For the antioxidant potential, three standard analytical protocols, namely, DPPH radical scavenging activity (RSA), reducing power assay (RPA), and total antioxidant capacity (TAC) assay, were adopted. The results showed that compound 2 was found to be more potent antioxidant as compared to 1. Fascinatingly, compound 2 displayed better EC50 results as compared to α-tocopherol while being comparable with ascorbic acid. The antiplasmodial assay data showed that both the compound exhibited good activity against chloroquine sensitive strain of Plasmodium falciparum (D10) and IC50 values were found to be less than 8 μM. The in silico molecular docking analyses were also performed for the determination of binding affinity of the isolated compounds using P. falciparum proteins PfLDH and Pfg27. The results showed that compound 2 has high docking score and binding affinity to both protein receptors as compared to compound 1. The demonstrated biological potentials declared that compound 2 could be the better natural antioxidant and antiplasmodial candidate.

Phenolic compounds were extracted from Mallotus philippinensis bark using methanol. Six fractions (I-VI) were separated from the extract on a Sephadex LH-20 column using ethanol and acetone-water as the mobile phases and were evaluated for their total antioxidant activity, antiradical activity against DPPH• (2,2-diphenyl-1-picrylhydrazyl radical), and reducing power. The total phenolics and tannin contents in the fractions were determined. The content of total phenolics in the fractions ranged from 54 mg/g (fraction I) to 927 mg/g (fraction VI). Condensed tannins were detected in fractions II-VI. Total antioxidant activity (TAA) of phenolic fractions of Mallotus philipinensis bark extract ranged from 0.58 mmol Trolox/g (fraction I) to 6.82 mmol Trolox/g (fraction IV). Fraction IV also showed the strongest antiradical activity against DPPH • and reducing power. Several phenolic constituents in the fractions were detected by RP-HPLC using a gradient solvent system with UV-DAD detection.

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Several extracts from Mallotus philippinensis fruits and bark were prepared and evaluated for their total antioxidant activity (TAA), antiradical activity against DPPH· (2,2‐diphenyl‐1‐picrylhydrazyl radical) and reducing power. The total phenolics and tannin contents in extracts were determined. The extract of the bark showed the strongest antiradical activity and reduction power; its TAA was 5.27 mmol Trolox equivalents/g. The TAA of other extracts ranged from 0.05 to 1.79 mmol Trolox equivalents/g extract. The content of total phenolics in the bark extract was 541 mg/g. The content of tannins in MP‐4, expressed as absorbance units per mg at 500 nm, was found to be 0.412. Several phenolic constituents in the extracts were detected by reverse‐phase high‐performance liquid chromatography using a gradient solvent system with UV‐DAD detection. Acetone was a suitable solvent for extraction of natural antioxidants from M. philippinensis fruits. PRACTICAL APPLICATIONS An acetonic and methanolic extraction of Mallotus philippinensis fruit and bark affords extracts that have been characterized as possessing strong antioxidant activities; this may open new avenues for the utilization of these extract as nutraceuticals. The biological activity of compounds present in the extracts has been well documented in many studies published in scientific journals. We want to emphasize that a procyanidin‐rich extract from pine (Pinus maritime) bark was patented under the trade name of Pycnogenol (PYC) and is utilized throughout the world as a nutritional supplement and as a phytochemical remedy for various diseases ranging from chronic inflammation to circulatory dysfunction (Packer et al. 1999).

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