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Introduction:The aspiration for light skin (fair complexion) is becoming pronounced in a greater number of people in the present times with natural products being more in demand than their synthetic counterparts. Research in the area of skin-lightening agents is an expanding field with the knowledge being updated regularly. In Ayurveda, varṇya, raktaprasādana, tvacya are few terms specifying skin lightening with respect to its modern counterpart i.e., Tyrosinase inhibition, the most commonly reported method of skin lightening.Aim:The present review is undertaken for screening twenty herbs from Varṇya Mahākaṣāya, Lodhrādi varṇya gaṇa, Elādi varṇa prasādana gaṇa and few varṇya formulations to evaluate their probable modes of action through which the skin lightening is effected as per both Ayurveda and biomedical concepts.Materials and Methods:Critical review of herbs to show varṇya property is compiled from various Ayurvedic texts as well as from multiple articles on the internet to justify their skin lightening property on the basis of data collected.Result and Conclusion:All the twenty herbs reviewed are found to act as varṇya directly (citation as varṇya) or indirectly (alleviation of pitta and rakta) as per Ayurveda and to interfere in melanogenesis pathway through tyrosinase inhibition as per biomedicine. This shows their potential to act as good skin whitening agents. Śuṇṭhi being a part of many varṇya formulations, is the only herb among all reviewed in the present study found to exhibit tyrosinase inhibition without any Ayurvedic citation of varṇya property.

Background:Lauha Bhasma (LB) is a complex herbomineral preparation widely used as an Ayurvedic hematinic agent. It is an effective remedy for chronic fever (jīrṇa jvara), phthisis (kṣaya), Breathlessness (śvāsa) etc., and possesses vitality enhancing (vājīkara), strength promoting and anti aging (rasāyana) properties.Objectives:The present work was conducted to establish the safety aspects of the use of Lauha bhasma.Setting and Design:LB was prepared by Ayurvedic procedures of purification (śodhana), sun drying (bhānupāka), sthālīpāka, followed by repeated calcination (māraṇa) and “nectarization” (amṛtīkaraṇa). The resultant product was subjected to acute and sub acute toxicity studies.Materials and Methods:Acute and subacute toxicity study of LB was conducted in albino rats. Criteria for assessment included ponderal changes, change in biochemical parameters viz., LFT and KFT and hematological parameters. Histopathological studies of different organs including liver, kidney, spleen, testis etc., were also conducted to observe pathological changes if any.Results:In the acute toxicity study, the animal group did not manifest any signs of toxicity and no mortality was observed up to 100 times the therapeutic dose (TD). Significant increase in blood urea (27.83%, P < 0.01), serum creatinine (30.92%, P < 0.05), Aspartate aminotransferase (15.09%, P < 0.05), and serum alkaline phosphatase (27.5%, P < 0.01) was evident in group IV (10 TD). A significant increase in serum total protein (6.04%, P < 0.05) level was observed in group III (5 TD). Histopathological examination of livers in group IV (10 TD) showed mild inflammation in terms of bile stasis, peri-portal hepatic inflammation and sinusoidal congestion; lymphocyte infiltration in kidney and intracellular deposits in the splenic tissue.Conclusion:Lauha Bhasma was found to be safe at the therapeutic dose and also at five times the therapeutic dose levels. However, alteration in some of the biochemical and haematological parameters along with histopathological findings were evident at the highest dose level.

A novel endoglucanase gene, celM, was cloned from a thermal spring metagenome. The gene was expressed in Escherichia coli, and the protein was extracted and purified. The protein catalyzed the hydrolysis of amorphous cellulose in a wide range of temperatures, 30–95°C, with optimal activity at 80°C. It was able to tolerate high temperature (80°C) with a half‐life of 8 h. Its activity was eminent in a wide pH range of 3.0–11.0, with the highest activity at pH 6.0. The enzyme was tested for halostability. Any significant loss was not recorded in the activity of CelM after the exposure to salinity (3 M NaCl) for 30 days. Furthermore, CelM displayed a substantial resistance toward metal ions, denaturant, reducing agent, organic solvent, and non‐ionic surfactants. The amorphous cellulose, treated with CelM, was randomly cleaved, generating cello‐oligosaccharides of 2–5 degree of polymerization. Furthermore, CelM was demonstrated to catalyze the hydrolysis of cellulose fraction in the delignified biomass samples, for example, sweet sorghum bagasse, rice straw, and corncob, into cello‐oligosaccharides. Given that CelM is a thermo‐halo‐tolerant GH5 endoglucanase, with resistance to detergents and organic solvent, the biocatalyst could be of potential usefulness for a variety of industrial applications.