The History and Development of Silk and Natural Silk
(I)Natural Silk——Oldest Pride of Chinese
All Chinese know the Silk Road in history and most people know the natural silk is originated from China, fostered and enhanced in Europe and America. It is even regarded as valuable treasure by Japanese in modern times. But now few people know why the natural silk is the oldest pride of the Chinese. Dating back to the ancient Chinese goddess who started to feed the silkworm, the Chinese has a close connection with the silk- the Bo in the Zhou and Qin dynasty, Hui in the Han dynasty, silk in the Tang dynasty and the Hangzhou silk and Sichuan figured satin in nowadays. In the development history of human civilization, the silk products have always been closely linked up with human life.
(II) Silk–The Unique Product of China
Before the opening of the Silk Road in 206BC, there was no silk in other places except China. The Silk Road was built in the Han dynasty (139 BC). It started as the emperor sent Zhang Qian to Yuezhi in the western regions. And it slowly spread to the west till 105 BC. It took a whole year for the silk to leave China and finally be sold in Rome after a 9600-kilometer journey. The silk transported to Rome through the Silk Road had the same value of gold, while the women in Rome still raced to wear it as a fashion. Chinese exported silk without telling the process of producing, which made a famous writer from Rome, Virgil, always believe that silk grew on trees in 100 BC.
China’s secrets of silkworm breeding and silk weaving had been kept for 3000 years. It was not until 522 AD, when two Nestorians from Rome stole 550 silkworm eggs from China to win the reward offered by the emperor Justinian and incubated them on the silkworm trees in Constantinople until them cocooning, that the westerners began to know the secrets of silk.
(III) Silk– The fiber nearest to human skin in the world
The conformation and feature of silk:
Silkworm is a kind of insect belonging to the order Lepidoptera. After peeling off their skin four times, the larva of silkworm would eject silk from mouth and fix it on the ground before put up the false work, which was used as the framework of cocoons, and the project of making cocoons need two to three days. Each mature silkworm has a pair of silk gland which consists of more than 900 gland cells.
At first, the silk protein which was secreted by the silk gland was liquid, and then hardens to silk fiber as soon as it exposes to air from the silk tube.
The silk fiber consist of inside and outside organizations–fibroin (about 75%)and sericin ( about 25%).
The fibroin itself still possesses 35% interval from the volume and the sericin outside also has the Amino Acids that is a hydrophil lateral chain, which make silk has a great function of absorption of moisture and still keep its comfort and coolness in spite of torridness.
Silk fiber can bear 35-44Kg/cm² pulling force in a unit of cross-sectional area and it can still restitute after elongating the 1/7 length of itself, which has excellent flexibility and is light, soft and fluffy.
Structure of Silk Protein
Silk is the continuous long fiber consists of two fibroins and the sericin covering outside.
The general composition of silk fiber:
Fibroin 70-80%
Sericin 20-30%
Lipid 0.4-0.8%
Hydrocarbon 1.2-1.6%
Pigment approximately 0.2%
Ash content approximately 0.7%
Utilization of Silk Protein
Silk Essence (Silk Amino Acids) Silk Peptide Silk Powder |
Sericin | |
Apply to functional nutritional health products, beauty and skincare products, hair care products and paints etc. | It is applied to the beauty cosmetics, fabrics, coatings of skin-friendly products, surfactants and food antioxidants, etc. |
The amino acid composition of fibroin (g/100g ):
Name of Amino Acid | Fibroin | Sericin | Structural Features |
△Aspartic Acid ASP | 2.60 | 17.35 | Acidic Amino Acid Polarity Side Chain |
*△ Threonine THR | 1.23 | 8.75 | Neutral Amino Acid Polarity Side Chain |
△ Serine SER | 13.74 | 30.14 | Neutral Amino Acid Polarity Side Chain |
Glycine GLY | 40.55 | 8.15 | Neutral Amino cid |
Alanine ALA | 32.52 | 3.06 | Neutral Amino Acid |
△ Glutamic Acid GLU | 2.32 | 5.55 | Acidic Amino Acid Polarity Side Chain |
*Valine VAL | 3.33 | 3.08 | Neutral Amino Acid |
*Isoleucine ILE | 0.92 | 0.67 | Neutral Amino Acid |
* Leucine LEU | 0.68 | 1.37 | Neutral Amino Acid |
yrosine TYR | 11.78 | 4.85 | Neutral Amino Acid |
*Phenylalanine(PHE) | 1.41 | 0.43 | Neutral Amino Acid |
*△Lysine LYS | 0.57 | 3.29 | Polarity side chains of Alkaline amino acid |
△Histidine HIS | 0.38 | 1.54 | Polarity side chains of Alkaline amino acid |
△Arginine ARG | 0.9 | 4.61 | Polarity side chains of Alkaline amino acid |
Proline PRO | 0.41 | 0.44 | Neutral Amino Acid |
Cystine CYS | 0.26 | 0.39 | Neutral Amino Acid |
*Methionine MET | 0.15 | 0.08 | Neutral Amino Acid |
*Tryptophan TRP | 0.41 | 0.56 | Neutral Amino Acid |
Recovery rate of amino acids (total) | 113.96 | 94.41 | |
Notes | * means essential amino acid for human body △ meanspolarity side-chain amino acid |
The Development of Silk Protein
Early in the medical monographs like Sun Simiao’s Valuable Prescriptions for Emergencies in the Tang Dynasty, Wang Huaiyin’s Peaceful Saint Benefit Prescription in the Song Dynasty and Li Shizhen’s Compendium of Materia Medica in the Ming Dynasty, there were records stating that silk has a very apparent skin-friendly ability. According to modern searches, the silk contains various amino acids and proteins. The proteins it contains are much more than pearl, and nitrogen of it is dozens of times higher than pearl’s, also it’s main amino acids contents are more than 10 times higher than pearl’s. So natural silk can be processed and refined into the hydrolysate of the natural silk protein. The silk protein hydrolyzate have a powerful penetration ability, which can be absorbed by skin dermis to act its moisturizing effects in 10 seconds, and can penetrate stratum corneum and combine with the skin epidermal cells, get absorbed by them as nutrition, participating and promoting cellular metabolism, so as to provide necessary nutrients for the metabolism, as well as to repair damaged skin and encourage skin cell regeneration.
Fibroin also has rapid development in the food industry. Japan began the research of turning silk into food as early as 1983. The earliest product was silk jelly, but such kind of gel’s fibroin molecules are jointed by thousands of amino acids and has relatively large molecular weight, which is difficult for the intestinal wall to absorb. In recent years, Japan has done a lot of research work to turn fibroin into food, and has developed a series of products with it, such as fibroin cakes, biscuits, noodles, soba, fruit juice gel, ice creams, candies, porridge, drinks, soy sauces and fibroin components-contained mushrooms, teas, capsules, tablets and so on, a variety of them have already been produced and attracted many consumers’ attention with their unique quality. They’ve become a new generation health food and nutriment of Japan. According to Rhee’s research, when the silk fibroin after hydrolysis with concentration of 0.3%, 0.6%, 0.9% respectively, added to the spicy pickled cabbage, it can inhibit the growth of lactic acid bacteria obviously. In 2004, the United States Dean food company exit milk products for students which is called “Silk”, and is popular in Colleges and Universities
Huzhou Xintiansi Bio-tech Co, Ltd. is the earliest and unique scientific and technological enterprise in Chine specializing in researching and developing the silk proteins and silkworm chrysalis proteins, based on which it has formed industrialization. 70% of our products are exported to the countries and regions as Japan, Korea, EU, U.S.A., Taiwan, etc. We have been the long-term supplier of lots of famous cosmetics and food companies both at home and abroad. The company selected the best silkworm cocoons in Huzhou, which was credited as the “capital of silk”, as raw materials, and originated the technologies like high pressure degumming and biological enzyme, dissociating the silk protein mildly in order to control the molecular weight effectively, which keeps the bio active of silk protein. After years of research: it invented the membrane separation technology and applied it to the selection and control of silk protein’s molecular weight as well as the separation between ashes and heavy metals, which ensures to produce the silk polypeptide with high-purity and high-activity and silk amino acids. Thus perfectly achieve the effects of nourishing, skin moisturizing, hair caring, moisture preserving and conditioning.
Efficacy of Fibroin
I.The skin care effect of Fibroin
(1) It has the functions of natural moisturizing and skin nourishing
(2) Possessing the action of inhibiting melanin production,
(3) Promoting the regeneration of skin tissue, guard against chapping and chemical damage
(4) Inhibiting the skin cancer
(5) Silk protein also possesses the function of antioxidant
(6) Silk protein also possesses the function of antioxidant
II. The hair-caring, hair-nourishing and hairdressing functions of silk protein.
Silk protein’s hair-caring function depends on the absorbency, absorptivity, film-forming ability and moisturizing type it received by hair. Compared with other protolysates (collagen, bone collagen, glutin and so on), the biggest feature of fibroin is that it is easy to be absorbed by the hair.
III. The Nutritional Function of Fibroin Food
Silk protein contains 18 types of amino acid, over 90 percent of which can be absorbed by human body. Its percentage of amino acids which are necessary to human body reaches more than 17 percent, higher than normal food. Therefore, it is a very good way of amino acid supplements to add the fibroin into the food. Japan began the research of turning silk into food as early as 1983. Like silk cake, biscuits, noodles, soba noodles, jelly glues, ice cream, candies, porridge, drink, soy and other kinds which contain components of silk, such as mushroom, tea, capsule, tablets and so on, they have appeared in the market, and are very popular among customers, which become the new generation of healthy food and nourishment in Japan.
IV. Medical functions of silk protein
a.The function of lowering blood pressure and cholesterol levels
b. Anticoagulant and anti-HIV activity
c. Anti-inflammatory effects of silk protein
d. Cancer prevention ability of silk protein
V. The Applications of Fibroin in Functional Materials, Fibers and Textiles
A.New electronic materials
B. Degradable biological materials
C. Synthetic macromolecule materials and products
D. Functional biological membranes
E. Functional fibers and textiles
Technological Process
XI’AN AOGU BIOTECH CO.,LTD is devoted into the research and innovation in natural nutritional supplements ingredients. Our own factory and lab with the strict quality control system to ensure quality stability and real price of silk protein. At the same time, we have our own source for the raw material to make sure the production ability.