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Background: Free radical stress leads to tissue injury and progression of disease conditions such as arthritis, hemorrhagic shock, atherosclerosis, diabetes, hepatic injury, aging and ischemia, reperfusion injury of many tissues, gastritis, tumor promotion, neurodegenerative diseases, and carcinogenesis. Safer antioxidants suitable for long term use are needed to prevent or stop the progression of free radical mediated disorders. Viscum articulatum is traditionally used for various oxidative stress induced disorders including liver disorders. Aims: The present study investigated antioxidant activities of the methanolic extract of Viscum articulatum in in vivo and in vitro models to provide scientific basis for the traditional usage of this plant. Materials and Methods: The in vitro antioxidant activity was evaluated by determining the ability of the extract to scavenge 2, 2-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide, 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), and hydrogen peroxide (H 2 O 2 ) which were assessed using spectroscopic methods. Results:The extract showed promising dose dependant free radical scavenging property in all the methods used. The extract effectively increased the superoxide dismutase and catalase activity and decreased lipid peroxidation in the treated groups indicating in vivo antioxidant activity. The extract also effectively decreased the serum levels of SGOT, SGPT, SALP, and total protein levels compared to toxicant control rats. Conclusion:The results obtained from this study indicate that Viscum articulatum is a potential source of antioxidant which would help in preventing many free radical mediated diseases.

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A serious consequence of marine biofouling on metallic structures is the insidious localized corrosion at the attachment sites of fouling organisms, such as barnacles. Albeit known, this phenomenon is poorly understood and currently mitigated using cost- and labor-intensive methods. In this work, we study the contribution to biofouling corrosion by a protein contained in the adhesive cement that barnacles secrete to attach to immersed substrates. We synthesize a specific cement protein of 20 kDa (CP20) from the barnacle Megabalanus rosa and study its corrosion behavior independently of the animal. Our results show that CP20 accelerates the corrosion rate of a marine-grade, mild steel from 0.7 to 1.6 mm year−1. Through chemical analysis of the corrosion products, protein adsorption studies on the metal surface, and cyclic voltammetry, we elucidate an intricate corrosion mechanism that relies on the strong adhesive properties of CP20 and its electrochemically active disulfide groups. Our results have far-reaching implications on the prediction and mitigation of biocorrosion in marine applications. Moreover, the protein-induced corrosion mechanism unveiled in our study may be extended to other scenarios to understand the degradation of metal alloys used in food storage and biomedical implants.