Mulberry leaves

Sir Joseph Swan, as a result of his quest for carbon fiber for lamp filaments (2), learned how to denitrate nitrocellulose using ammonium sulfide. In 1885 he exhibited the first textiles made from this new artificial sHk, but with carbon fiber being his main theme he failed to foUow up on the textile possibihties. Meanwhile Count Hilaire de Chardoimet (3) was researching the nitrocellulose route and had perfected his first fibers and textiles in time for the Paris Exhibition in 1889. There he got the necessary financial backing for the first Chardoimet silk factory in Besancon in 1890. His process involved treating mulberry leaves with nitric and sulfuric acids to form cellulose nitrate which could be dissolved in ether and alcohol. This collodion solution could be extmded through holes in a spinneret into warm air where solvent evaporation led to the formation of soHd cellulose nitrate filaments. 

Examine the page before you Not the words, but the material itself, paper. We often take this product for granted, but paper-making is one of the most important developments in the advance of civilization. According to legend, the first sheets of paper were made from mulberry leaves in China in AD 105. For many centuries paper was made in individual sheets, so it was a rare and expensive commodity. Paper-making machines were first developed in the early years of the nineteenth century. The development of machinery that allowed high-speed paper production was partially responsible for the increase in literacy and education of people around the world. 

The feeling of a spider web may be unsettling, but a similar natural material has been used for centuries to make silk fabric that is prized for its smooth texture. Silkworms produce the silk fibers used to make clothing. They feast on mulberry leaves and convert the molecules from these leaves into silk, from which they spin cocoons. 

FIGURE 24.1 The pathway of carotenoid transport in the silkworm. Carotenoids are absorbed from dietary mulberry leaves into the intestinal mucosa, transferred to the hemolymph (1), transported in the hemolymph by plasma lipoproteins (2), and accumulated in the silk gland (3). 

Sugimura Y, Mori T, Nitta I, Kotani E, Furusawa T, Tatsumi M, Kusakari S-I, Wada M, Morita Y. Calcium deposition in idioblasts of mulberry leaves. Ann Bot 1999 ... 

Matsuyama, S., Kuwahara, Y., and Suzuki, T., A new 2-arylbenzofuran, w-hydroxymoracin N, from mulberry leaves. Agricultural and Biological Chemistry, 55, 1409, 1991. 

Rayon is made from cellulose. Count Chardonnet made the synthetic fibre from mulberry leaves. Chardonnet was studying the diseases of the silkworms. He was inspired by the silkworm spinning silk to find a way to make artificial silk. He made artificial silk from the cellulose he obtained from mulberry leaves by a complex process. 

There are all sorts of silk that are found in nature. The stuff that is usually found in textiles comes from silkworms (Bombyx mori). They are not really worms, but the larvae of moths. They emerge from very small eggs with an incredible lust for mulberry leaves, which they consume until they are ready to. pupate and weave a cocoon around themselves. Unlike spiders, which spin silk from their rear end, silkworm silk is actually hardened saliva, which comes out of the mouth. The larva has a small spinneret on its lip, through which the silk emerges. The cocoon is formed from a single strand of silk that... 

Butylamine occurs naturally in some foods. These include kale (7ppm) pickles cucumbers in aromatic vinegar (0.6 ppm) cucumbers pickled with mustard (5.3 ppm) Tilsiter cheese (3.7ppm) brown bread (1.1 ppm) mulberry leaves fish and seafood. n-Butylamine has been identified as a volatile component of boiled beef. Butylamines have been reported to be a component of animal waste, perhaps from decomposition of manure. 

Mulberroside F (also known as 3 -di-0-P-D-glucopyra-noside and moracin M-6), extracted from mulberry leaves, inhibits tyrosinase activity, in the conversion of dopa (3,4-dihydroxy-P-phenylalanine) into dopachrome (dopa oxidase activity). This tyrosinase-inhibiting activity has been measured as 4.5 times more powerful than that of kojic acid. Mulberroside F also has an antioxidant activity on the superoxide anion. 

This is the term applied to the cultivation of silkworms. The first essential for success is a good stock of mulberry trees. The eggs are hatched in incubating rooms which are maintained between 20° and 25°C (68° and 77°F). As the worms hatch they are transferred to frames where they are fed on chopped mulberry leaves. Plenty of fresh air and cleanliness are essential for the well-being of the worms because they are subject to many diseases, these being one of the great hazards of sericulture. Pasteur studied the causes of sickness in silkworms, and this particular work was a part of... 

Silks derived from moths other than Botnhyx viori, which do not feed on mulberry leaves, are classified as Wild silks. There arc many wild silks in existence but only a few have found limited commercial use. In Japan a species known as Antheraea yama-mai feeds on oak leaves and produces a thread which, in the past, found some uses. In India, Antheraea myiitia also finds nourishment from oak leaves, and Atlaais ricini thrives on the foliage of the castor-oil plant. 

The life eycle of B. mori is summarized in Fig. 23.1 [21]. In about 50 days it eompletes its life cycle of four different metamorphosing phases egg or embryo, larva, pupa and adult (moth). Of the life cycle, about half is the larval stage, the only stage at which they consume food, mulberry leaves. Pupation occurs at the end of spinning (or cocoon formation) the latter takes... 

The silkworm, which feeds on ascorbic acid-rich mulberry leaves, was reported to require ascorbic acid (L6). 

Natural fibers These fibers come directly from plants or animals. They Include wool, cotton, linen, hemp, and silk (from the cocoons of silkmoth caterpillars that feed on mulberry leaves). 

Mention should also be made of the report by Vasantharajan and Bhat (1968) to the effect that mulberry leaves harbor populations of microorganisms, including Azoto-bacter and Beijerinckia. Plants grown under aseptic conditions showed increased growth and nitrogen content following inoculation of the leaf or root with Azotobacter. Further research is needed before proper evaluation of this work can be made. 

Once more, we look to Louis Pasteur. In 1862, French silk industry representatives prevailed upon him to save them from a potentially catastrophic epidemic that was afflicting silkworms. Pasteur traced the problem to a tiny parasite that infected the worms and the mulberry leaves upon which they fed. Upon his recommendation, the worms and their food supply were destroyed. After getting off to a fresh start with healthy new worms, the silk industry flourished once more. Through a peculiar sequence of events, this scientific rescue led to the development of silk s first real commercial competitor rayon. 

Suntornsuk, L., Kasemsook, S., and Wongyai, S., Quantitative analysis of aglycone quercetin in mulberry leaves (Moms alba L.) by capillary zone electrophoresis. Electrophoresis, 24, 1236, 2003. 

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