Hyaluronic acid HA also called
Hyaluronic PS-1145 (HA), also called hyaluronan is widely distributed in Extra Cellular Matrix of soft connective tissues including skin, umbilical cord and synofial fluid (Hanamura et al., 2008). Hyaluronic acid has a unique ability to hold 6000mL of water in 1mg of HA and plays an important role in reducing wrinkles, wound healing and keeping the skin smooth and hydrated (Necas et al., 2008, Jegasothy et al., 2014). Enzyme hyaluronidase breakdown HA in to small oligosaccharide molecules by cleaving the N-acetylglucosamidic bonds via a β-elimination process. By catalyzing the hydrolysis of HA, hyaluronidase decreases the viscosity of body fluids and increases the permeability of connective tissues (Stern and Jedrzejas, 2006, Necas et al., 2008). Hyaluronidase inhibitors are therefore effective regulating agents, that maintain the balance between the anabolism and catabolism of HA, and this keep skin moist as well as smooth.
Pollutants, UV radiation, smoke and xenobiotics generate exogenous ROS inside the human body. Reactive oxygen species restrains antioxidant defense mechanisms, resulting severe oxidative stress and contribute to aging, carcinogenesis, inflammation, and cell proliferation etc. Beside these ROS leads to overproduction of elastases, reduction and degeneration of collagen, deposition of glycosaminoglycans, induces melanin biosynthesis, and may induce proliferation of melanocytes (Fisher et al., 2002, Moon et al., 2010, Inomata et al., 2003). These observations suggest that the antioxidants play a vital role by neutralizing ROS in the management of oxidative stress.
Medicinal plants have been extensively used as active ingredients in cosmetics and therapeutics, as beautifying agents and also a remedy for dermatological disorders such as eczema, acne, hyperpigmentation, and photoaging for centuries. These provide a largely unexplored source for the potential development of active ingredients for cosmetic formulations. Hence cosmeceuticals is a growing market segment, driven by the rising desire of people to maintain healthy skin without using chemicals. Sri Lanka holds a treasure of high biodiversity, which has potential applications for use in cosmetic industry (Perera et al., 2016, Samaradivakara et al., 2016). As part of the effort to find new functional ingredients for skin-whitening and anti-aging preparations, 15 less exploited plants grown in Sri Lanka, were investigated evaluating their in-vitro anti-tyrosinase, anti-hyaluronidase anti-elastase enzyme inhibitory, and anti oxidant activities, Total Phenolic Content (TPC) and Total Flavanoid Content (TFC).
Results and discussion New and emerging trends of natural cosmetic products encourage researchers to find new cosmeceuticals. According to Persistence Market Research and Grand View Research, current global natural and organic personal care products market is valued about US$ 11 billion and expected to reach US$ 22 billion by 2022. Hence, Plant extracts have an increase global demand that can be used for de-pigmenting, anti-wrinkle, and other cosmeceutical purposes because of low incidence of side effects and compatible with all skin types (Ashawat et al., 2008). In the current investigation tyrosinase, elastase, hyaluronidase inhibitory and antioxidant activities of Sri Lankan medicinal plants were evaluated for their use in skin whitening, aging and skin health.
Conclusion From all these results, it is evident that ethanolic extracts of barks A. nobilis, A. heterophyllus, and A. altilis are rich sources of tyrosinase inhibitory bio active compounds due to its ability to inhibit tyrosinase enzyme. These extracts are also good sources of hyaluronidase inhibitors and as well as anti-oxidants. Artocarpus nobilis, A. altilis showed better tyrosinase inhibitory activity compared to the positive control kojic acid. Eleocarpus serratus bark showed highest elastase inhibitory activity and DPPH free radical scavenging activities. Ethanolic extract of C. aromatica rhizomes was found to be more active against hyaluronidase compared to other tested plant extracts. The bioactivities, exhibited by these plant extracts reflect the use of extracts as active agents in cosmeceuticals which might used to treat various skin disorders such as hyper-pigmentation, to obtain lighter skin complexion, wrinkling, pre-mature aging, and biological aging.