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Lawsone
Lawsone (2-hydroxy-1,4-naphthoquinone), also known as hennotannic acid, is a red-orange dye present in the leaves of the henna plant (''Lawsonia inermis''), for which it is named, as well as in the flower of water hyacinth ('' Eichhornia crassipes''). Humans have used henna extracts containing lawsone as hair and skin dyes for more than 5,000 years. Lawsone reacts chemically with the protein keratin in skin and hair via Michael addition, resulting in a strong permanent stain that lasts until the skin or hair is shed. The darker colored ink is due to more lawsone-keratin interactions occurring, which evidently break down as the concentration of lawsone decreases and the tattoo fades. Lawsone strongly absorbs UV light, and aqueous extracts can be effective sunless tanning and sunscreens. Lawsone is a 1,4-naphthoquinone derivative. Lawsone isolation from ''Lawsonia Inermis'' can be difficult due to its easily biodegradable nature. Isolation involves four steps: # extraction with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawsone Methyl Ether
Lawsone (2-hydroxy-1,4-naphthoquinone), also known as hennotannic acid, is a red-orange dye present in the leaves of the henna plant (''Lawsonia inermis''), for which it is named, as well as in the flower of water hyacinth (''Eichhornia crassipes''). Humans have used henna extracts containing lawsone as hair and skin dyes for more than 5,000 years. Lawsone reacts chemically with the protein keratin in skin and hair via Michael addition, resulting in a strong permanent stain that lasts until the skin or hair is shed. The darker colored ink is due to more lawsone-keratin interactions occurring, which evidently break down as the concentration of lawsone decreases and the tattoo fades. Lawsone strongly absorbs UV light, and aqueous extracts can be effective sunless tanning and sunscreens. Lawsone is a 1,4-naphthoquinone derivative. Lawsone isolation from ''Lawsonia Inermis'' can be difficult due to its easily biodegradable nature. Isolation involves four steps: # extraction with an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henna
Henna is a dye prepared from the plant ''Lawsonia inermis'', also known as the henna tree, the mignonette tree, and the Egyptian privet, the sole species of the genus ''Lawsonia''. ''Henna'' can also refer to the temporary body art resulting from the staining of the skin from the dyes. After henna stains reach their peak color, they hold for a few days, then gradually wear off by way of Exfoliation (cosmetology), exfoliation, typically within one to three weeks. Henna has been used since antiquity in ancient Egypt and Indian subcontinent to dye skin, hair and fingernails, as well as fabrics including silk, wool, and leather. Historically, henna was used in West Asia including the Arabian Peninsula and in Carthage, other parts of North Africa, West Africa, Central Africa, the Horn of Africa and the Indian subcontinent. The name "henna" is used in other skin and hair dyes, such as ''black henna'' and ''neutral henna'', neither of which is derived from the henna plant. Etymology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impatiens Balsamina
''Impatiens balsamina'', commonly known as balsam, garden balsam, rose balsam, touch-me-not or spotted snapweed, is a species of plant native to India and Myanmar. It is an annual plant growing to 20–75 cm tall, with a thick, but soft stem. The leaves are spirally-arranged, 2.5–9 cm long and 1–2.5 cm broad, with a deeply toothed margin. The flowers are pink, red, mauve, purple, lilac, or white, and 2.5–5 cm diameter; they are pollinated by bees and other insects, and also by nectar-feeding birds.Huxley, A., ed. (1992). ''New RHS Dictionary of Gardening''. Macmillan . The ripe seed capsules undergo explosive dehiscence. This species has been used as indigenous traditional medicine in Asia for rheumatism, fractures, and other ailments. In Korean folk medicine, this impatiens species is used as a medicine called ''bongseonhwa dae'' (봉선화대) for the treatment of constipation and gastritis. Chinese people used the plant to treat those bitten by snakes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juglone
Juglone, also called 5-hydroxy-1,4-naphthalenedione (IUPAC) is an organic compound with the molecular formula C10H6O3. In the food industry, juglone is also known as C.I. Natural Brown 7 and C.I. 75500. It is insoluble in benzene but soluble in dioxane, from which it crystallizes as yellow needles. It is an isomer of lawsone, which is the staining compound in the henna leaf. Juglone occurs naturally in the leaves, roots, husks, fruit ( the epicarp), and bark of plants in the Juglandaceae family, particularly the black walnut (''Juglans nigra''), and is toxic or growth-stunting to many types of plants. It is sometimes used as an herbicide, as a dye for cloth and inks, and as a coloring agent for foods and cosmetics. History The harmful effects of walnut trees on other plants have been observed for at least two millennia. The ancient civilizations of Greece and Rome used the walnut for its cytotoxic properties as did residents of the American South for easily gathering fish w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Oxford
, mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor = The Lord Patten of Barnes , vice_chancellor = Louise Richardson , students = 24,515 (2019) , undergrad = 11,955 , postgrad = 12,010 , other = 541 (2017) , city = Oxford , country = England , coordinates = , campus_type = University town , athletics_affiliations = Blue (university sport) , logo_size = 250px , website = , logo = University of Oxford.svg , colours = Oxford Blue , faculty = 6,995 (2020) , academic_affiliations = , The University of Oxford is a collegiate research university in Oxf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunscreen
Sunscreen, also known as sunblock or sun cream, is a photoprotective topical product for the skin that mainly absorbs, or to a much lesser extent reflects, some of the sun's ultraviolet (UV) radiation and thus helps protect against sunburn and most importantly prevent skin cancer. Sunscreens come as lotions, sprays, gels, foams (such as an expanded foam lotion or whipped lotion), sticks, powders and other topical products. Sunscreens are common supplements to clothing, particularly sunglasses, sunhats and special sun protective clothing, and other forms of photoprotection (such as umbrellas). The first sunscreen in the world was invented in Australia, by chemist H.A. Milton Blake, in 1932 formulating with the UV filter 'salol' ( phenyl salicylate) at a concentration of 10%. Its protection was verified by the University of Adelaide and it was also produced commercially by Blake's company, Hamilton Laboratories. Despite sunscreen being relatively new, sun protection pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Dyes
Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources—roots, berries, bark, leaves, and wood—and other biological sources such as fungi. Archaeologists have found evidence of textile dyeing dating back to the Neolithic period. In China, dyeing with plants, barks and insects has been traced back more than 5,000 years.Goodwin (1982), p. 11. The essential process of dyeing changed little over time. Typically, the dye material is put in a pot of water and heated to extract the dye compounds into solution with the water. Then the textiles to be dyed are added to the pot, and held at heat until the desired color is achieved. Textile fibre may be dyed before spinning or weaving ("dyed in the wool"), after spinning ("yarn-dyed") or after weaving ("piece-dyed"). Many natural dyes require the use of substances called mordants to bind the dye to the textile fibres. Mordants (from the Latin verb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genipin
Genipin is a chemical compound found in '' Genipa americana'' fruit extract. It is an aglycone derived from an iridoid glycoside called geniposide which is also present in fruit of ''Gardenia jasminoides''. Genipin is an excellent natural cross-linker for proteins, collagen, gelatin, and chitosan cross-linking. It has a low acute toxicity, with i.v. 382 mg/kg in mice, therefore, much less toxic than glutaraldehyde and many other commonly used synthetic cross-linking reagents. Furthermore, genipin can be used as a regulating agent for drug delivery, as the raw material for gardenia blue pigment preparation, and as the intermediate for alkaloid syntheses. The blue color of genipin is stabilized in milk due to the natural pH of milk ''In vitro'' experiments have shown that genipin blocks the action of the transporter uncoupling protein 2 Mitochondrial uncoupling protein 2 is a protein that in humans is encoded by the ''UCP2'' gene. Mitochondrial uncoupling proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ninhydrin
Ninhydrin (2,2-dihydroxyindane-1,3-dione) is an organic compound with the formula C6H4(CO)2C(OH)2. It is used to detect ammonia and amines. Upon reaction with these amines, ninhydrin gets converted into deep blue or purple derivatives, which are called Ruhemann's purple. Ninhydrin is most commonly used to detect fingerprints, as the terminal amines of lysine residues in peptides and proteins sloughed off in fingerprints react with ninhydrin. Ninhydrin is a white solid that is soluble in ethanol and acetone. Ninhydrin can be considered as the hydrate of indane-1,2,3-trione. History Ninhydrin was discovered in 1910 by the German-English chemist Siegfried Ruhemann (1859–1943). In the same year, Ruhemann observed ninhydrin's reaction with amino acids. In 1954, Swedish investigators Oden and von Hofsten proposed that ninhydrin could be used to develop latent fingerprints. Uses Ninhydrin can also be used to monitor deprotection in solid phase peptide synthesis (Kaiser test). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UV Light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contact. For ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
