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Smart Factory of Microalgae in Environmental Biotechnology
Published in Pau Loke Show, Wai Siong Chai, Tau Chuan Ling, Microalgae for Environmental Biotechnology, 2023
Shazia Ali, Kuan Shiong Khoo, Hooi Ren Lim, Hui Suan Ng, Pau Loke Show
Due to their high protein content, microalgae are a valuable source of active ingredients for the cosmetic industry. Microalgae contain amino acids of around 5–20%; carbohydrates up to 20%; lipids; vitamins primarily B, C, and A; and traces of elements such as zinc, copper, and iron (Couteau and Coiffard 2018). Melanin, a complex polymer pigment that gives human skin its colour and also serves as a protective barrier for human skin cells, absorbs UV rays when skin is exposed to them for a prolonged period (Brenner and Hearing 2008). Skin pigmentation is caused by an excessive amount of melanin being produced, which must be controlled. Fucoxanthin, which is an algal pigment from the brown algae Macrocystis, Alaria chorda, and Laminaria japonica, can assist in inhibiting skin diseases promoters such as tyrosinase activity and melanogenesis (Foo et al. 2021). Sun protection, skincare, and hair care products contain the algae Arthrospira and Chlorella (Spolaore et al. 2006). The extract of C. vulgaris increases collagen production in the skin, resulting in the reduction of wrinkles and the formation of tissue regeneration (Thiyagarasaiyar et al. 2020).
Cellulose – A Sustainable Material for Biomedical Applications
Published in Ashwani Kumar, Mangey Ram, Yogesh Kumar Singla, Advanced Materials for Biomechanical Applications, 2022
N. Vignesh, K. Chandraraj, S.P. Suriyaraj, R. Selvakumar
Human skin is the major barrier protecting vital body functions from the external environment. The skin itself functions as a filter for maintaining the levels of water and salt, excretes toxins and shields the body from harmful ultraviolet radiation. An injury to the skin as a result of burns and cuts increases the risk of infection and forms the site for the entry of pathogens and other harmful toxins from the surrounding environment [75]. A wound dressing material ideally targets the protection of the wound site and promotes wound healing. It also forms a barrier against microbial infection and facilitates the exchange of gases and the maintenance of moisture. During the wound healing process, the regeneration of new tissue occurs in different stages such as clot formation, granulation, proliferation of endothelial and fibroblast cells and blood vessel formation (Figure 4.6a).
Biological Effects of Millimeter and Submillimeter Waves
Published in Ben Greenebaum, Frank Barnes, Biological and Medical Aspects of Electromagnetic Fields, 2018
Stanislav I. Alekseev, Marvin C. Ziskin
The human skin consists of three individual layers: the epidermis, dermis, and hypodermis. The epidermis, the outermost layer of skin, is about 0.1 mm thick but on the palms of the hands it can be 0.7 mm thick or more (Bloom and Fawcett, 1968; Odland, 1971; El Gammal et al., 1999; Welzel et al., 2004). The majority of cells in the epidermis are keratinocytes. The surface layer of the epidermis is called the SC. The SC is made up of flattened dead keratinocytes, which have lost their internal structure. The thickness of the SC in the forearm skin is about 0.012–0.018 mm (Kligman, 1964; Rajadhyaksha et al., 1999; Huzaira et al., 2001; Caspers et al., 2003; Sandby-Moller et al., 2003). The rest of the epidermis (without the SC) consisting of live cells is called the viable epidermis. The dermis is organized into a papillary (outer) and a reticular (inner) region. The distinction between the two layers is based mostly on their differences in connective tissue. Literature data of the dermis thickness depend on location and on the methods used for thickness measurements, and vary from 1.0 to 2.0 mm (Meema et al., 1964; Black, 1969; Shuster et al., 1975; Dykes and Marks, 1977; Fornage and Deshayes, 1986; Branchet et al., 1990; Gniadecka and Quistorff, 1996). The hypodermis is composed mainly of fat cells and connects the dermis to underlying tissues and muscle.
A method to predict burn injuries of firefighters considering heterogeneous skin thickness distribution based on the instrumented manikin system
Published in International Journal of Occupational Safety and Ergonomics, 2021
Epidermis, dermis and subcutaneous tissues are regarded as the three main layers of human skin. Heat transfer in the skin is a complex process including conduction combined with other physiological processes such as metabolic heat generation, blood perfusion and evaporation. Pennes bioheat transfer equation [6], based on Fourier’s law for conduction heat transfer, is frequently used to model skin heat transfer. Kumar et al. [7] dealt with the heat transfer in triple-layer skin tissue for three different types of surface heating using the time fractional bioheat model, which can describe dynamic events that occur in biological tissue. Zhai et al. [8] analyzed different mechanisms of steam diffusion through the multiple skin layers, as well as the moisture-assisted Pennes bioheat transfer. Various experiments were conducted on animals and human skin in order to investigate skin burns, which were associated with temperature evolution and exposure time [9,10]. According to the extent of burn injuries, burn wound depths are classified as first-degree, second-degree and third-degree burns. First-degree burns may be induced by sun exposure or hot liquids with low viscosity, which only involves the epidermis [1]. The dermis is involved in second-degree burns. Flame is one of the causes of third-degree burns, in which the full thickness of skin suffers thermal damage [1]. A classification of burns as superficial, superficial partial thickness, deep partial thickness and full thickness was also defined to reflect damage of the skin [11,12].
Effects of anti-wrinkle and skin-whitening fermented black ginseng on human subjects and underlying mechanism of action
Published in Journal of Toxicology and Environmental Health, Part A, 2020
Jin Ju Park, Junmin An, Jung Dae Lee, Hyang Yeon Kim, Jueng Eun Im, Eunyoung Lee, Jaehyoun Ha, Chang Hui Cho, Dong-Wan Seo, Kyu-Bong Kim
The skin is a protective outer covering extending throughout the human body which protects internal tissues and organs. Human skin is composed of three primary layers; the epidermis, dermis, and hypodermis. The epidermis, the outermost layer of the skin, functions by protecting the body and is predominantly composed of keratinocytes, melanocytes, Langerhans, and Merkel cells. Keratinocytes are the most abundant cells found in the epidermis and function as a barrier against the external environment (McGrath, Eady, and Pope 2004; Winkelmann and Breathnach 1973). Melanocytes produce the colored pigment of melanin. Melanin occurs in two forms in human skin: eumelanin and pheomelanin. Eumelanin is black and brown melanin and common throughout the body, while pheomelanin is a red or yellow melanin pigment (Wakamatsu and Ito 2002). Melanin is biosynthesized from tyrosine. Tyrosine is converted to DOPA (3,4-dihydroxy-L-phenylalanine), which is then oxidized to DOPA-quinone and subsequently converted to DOPA-chrome. Melanin is finally generated through several intermediates and a series of biochemical steps. Tyrosinase plays a key role in the melanin biosynthetic pathway by converting tyrosine to DOPA (Choi et al. 2001; D’Mello et al. 2016; Kong et al. 2000). The inhibition of tyrosinase leads to blockade of melanin production. The reaction of tyrosinase (activity or inhibition) with test material is used as a measure of efficacy of the compound. Melanin, which is synthesized and matures in the melanosome, is transferred to keratinocytes where pigmentation occurs. Skin color is determined by melanin in the melanocytes. Melanocytes function predominantly by producing melanin pigment, which protects against and absorbs harmful ultraviolet (UV) radiation (D’Mello et al. 2016).
Effects of anti-wrinkle and skin-whitening fermented black ginseng on human subjects and underlying mechanism of action
Published in Journal of Toxicology and Environmental Health, Part A, 2020
Jin Ju Park, Junmin An, Jung Dae Lee, Hyang Yeon Kim, Jueng Eun Im, Eunyoung Lee, Jaehyoun Ha, Chang Hui Cho, Dong-Wan Seo, Kyu-Bong Kim
The skin is a protective outer covering extending throughout the human body which protects internal tissues and organs. Human skin is composed of three primary layers; the epidermis, dermis, and hypodermis. The epidermis, the outermost layer of the skin, functions by protecting the body and is predominantly composed of keratinocytes, melanocytes, Langerhans, and Merkel cells. Keratinocytes are the most abundant cells found in the epidermis and function as a barrier against the external environment (McGrath, Eady, and Pope 2004; Winkelmann and Breathnach 1973). Melanocytes produce the colored pigment of melanin. Melanin occurs in two forms in human skin: eumelanin and pheomelanin. Eumelanin is black and brown melanin and common throughout the body, while pheomelanin is a red or yellow melanin pigment (Wakamatsu and Ito 2002). Melanin is biosynthesized from tyrosine. Tyrosine is converted to DOPA (3,4-dihydroxy-L-phenylalanine), which is then oxidized to DOPA-quinone and subsequently converted to DOPA-chrome. Melanin is finally generated through several intermediates and a series of biochemical steps. Tyrosinase plays a key role in the melanin biosynthetic pathway by converting tyrosine to DOPA (Choi et al. 2001; D’Mello et al. 2016; Kong et al. 2000). The inhibition of tyrosinase leads to blockade of melanin production. The reaction of tyrosinase (activity or inhibition) with test material is used as a measure of the efficacy of the compound. Melanin, which is synthesized and matures in the melanosome, is transferred to keratinocytes where pigmentation occurs. Skin color is determined by melanin in the melanocytes. Melanocytes function predominantly by producing melanin pigment, which protects against and absorbs harmful ultraviolet (UV) radiation (D’Mello et al. 2016).