• Journal of Sericultural and Entomological Science
• /
• v.41 no.1
• /
• pp.54-60
• /
• 1999

Antheraea pernyi silk powder was prepared by treatment with HCl and NaOH. The degree of hydrolysis of Antheraea pernyi silk fiber was examined. The morphology and structural characteristics of Antheraea pernyi silk powder were investigated by using SEM, FTIR and X-ray diffractometer. As the concentration of HCl and NaOH and tratment temperature increased, in general, the degree of hydrolysis of Antheraea pernyi silk fiber increased. On the other hand, the degree of hydrolysis of Antheraea pernyi treated with 3 N NaOH at 120$^{\circ}C$ for 24 hr was 70 wt%, which was lower than that of 90$^{\circ}C$(83 wt%). The morphology of acid/alkali resistance fraction of Antheraea pernyi silk fibroin was transformed from fiber form to powered one with an increase of hydrolysis. The conformation of Antheraea pernyi silk powder characterized by FT-IR spectrometer and X-ray diffractometer ${\beta}$-sheet and ${\alpha}$-helix structure.

• Food Science and Industry
• /
• v.55 no.2
• /
• pp.154-165
• /
• 2022

Humans have been breeding the mulberry silkworm for the long period of time to obtain silk fabric and nutrient-rich pupae. Currently, silkworm larvae, pupae, and silk-Fibroin hydrolysates are registered as food raw materials, while silkworm feces and Bombyx batryticatus are registered as Korean traditional medicines. Among sericulture products, individually recognized health functional food ingredients include silk-protein acid-hydrolysates for immunity enhancement, Fibroin-hydrolysates for memory improvement, and freeze-dried 5^th instar and 3^rd-day-silkworm powder for lowering-blood sugar. Recently, HongJam produced by steaming and freeze-drying mature silkworms were reported to have various health-promoting effects such as preventing the onset of Alzheimer's disease and Parkinson's disease, enhancing gastro-intestinal functions, improving skin-whitening and hair growth, and extending healthspan. By consuming silkworm products with various health-promoting effects, it is possible to increase the healthspan of human beings, thereby reducing personal and national medical expenses, resulting in increasing the individual's happiness.

• Journal of Life Science
• /
• v.10 no.5
• /
• pp.511-518
• /
• 2000

This study was designed to investigate the effects of silk fibroin powder (SFP : Mw 500) on oxidative stress and membrane fluidity in brain membranes of rats. Sprague-Dawley (SD) male rats (160$\pm$10 g) were fed basic diet (control group), and experimental diets (SFP-2.5 and SFP-5.0 groups) added 2.5 and 5.0 g/kg BW/day for 6 weeks. Cholesterol level was significantly decreased about 8.0% in brain microsomes of SFP-5.0 group only compared with control group. Membrane fluidities were significantly increased (12.9% and 15.2%, respectively) in brain microsomes of SFP-2.5 and SFP-5.0 groups, but significant difference between in brain mitochondria of these two groups could be not obtained. Basal oxygen radicals (BOR) in brain mitochondria and microsomes were significantly ingibited (10.4%, and 24.0%, 7.9% and 14.9%, respectively) by SFP-2.5 and SFP-5.0 groups compared with control group. Induced oxygen radicals (IOR) in brain mitochondria and microsomes were significantly inhibited (11.8% and 14.1%, respectively) by SFP-5.0 groups compared with control group compared with control group. Lipid peroxide (LPO) levels were dose-dependently decreased (12.9% and 21.9%, 13.2% and 22.5%, respectively) in brain mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group. Oxidized protein (OP) levels were significantly decreased (15.7% and 17.1%, 16.7% and 15.7%, respectively) in brain mitochondria and microsomes of SFP-2.5 and SFP-2.5 and SFP-5.0 groups compared with control group. These results suggest that administration of SFP may play an effective role in a attenuating a oxidative stress and increasing a membrane fluidity in brain membranes.

• Journal of Sericultural and Entomological Science
• /
• v.42 no.1
• /
• pp.58-64
• /
• 2000

This study was designed to investigate the effects of silk fibroin powder (Mw 500) on oxidative stress and membrane fluidity in liver membranes of rats. Sprague-Dawley (SD) male rats (160$\pm$10g) were fed basic diet (control group), and experimental diets (SEP-2.5 and SFP-5.0 groups) added 2.5 and 5.0 g/kg BW/day for 6 weeks. Cholesterol levels resulted in a significant decrease (12.1% and 9.0%, respectively) in the liver mitochondria and microsomes of SEP-5.0 group compared with control group. Membrane fluidity as significantly increased (16.1% and 16.5%, 5.8% and 17.4%) in the liver mitochondria and microsomes were significantly inhibited (16.1% and 18.3%, 8.1% and 15.1%, respectively) at the SFP-2.5 and SEP-5.0 groups compared with control group. Induced oxygen radicals (BOR) in liver mitochondria and microsomes were significantly inhibited (16.1% and 18.3%, 8.1% and 15.1%, respectively) at the SFP-2.5 and SEP-5.0 groups compared with control group. Induced oxygen radicals (IOR) in liver microsomes were significantly inhibited (17.0% and 26.6%, respectively) at the SFP-2.5 and SFP-5.0 groups compared with control group, but IOR in liver mitochondria was significantly inhibited about 12.3% at the SWP-400 group only compared with control group. Lipid peroxide (LPO) levels were significantly decreased (8.3% and 18.0%, 13.4% and 18.4%, respectively) in the liver mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group. Oxidized protein (OP) levels were dose-dependently decreased (5.4% and 11.6%, 19.0% and 24.4%, respaectively) in the iver mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group. These results suggest that administration of SFP may play an effective role in attenuating an oxidative stress and increasing a membrane fluidity in liver membranes.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.34 no.2
• /
• pp.17-22
• /
• 2017

Cooked mature silkworms have received increasing attention as a new source of income for sericultural farms. Quality improvement of these worms as the end-product requires prevention of the following: inclusion of unfertilized silkworm eggs, mixing with impurities, producing undercooked or overcooked mature larvae, and mixing spewed silk substance. Preventing unfertilized eggs and impurities and reducing undercooked or overcooked mature larvae can be achieved by sericultural farms. However, the prevention of spewed silk substance requires the development of new techniques. This study developed new techniques for optimum cold storage temperature, soaking, and hydro-thermal treatment to minimize the spewing of mature larvae prior to steaming: when larvae mature after 7 days on the $5^{th}$ instar, they should be soaked in water at room temperature of $25^{\circ}C$ immediately upon collection and stored at $8^{\circ}C$ for less than 3 days. They should be soaked in boiling water for approximately 10 s immediately before steaming to kill the larvae and cooked with steam. This method allows for the production of high-quality mature larvae without spewed silk substance. These new techniques will considerably improve the production of well-cooked quality mature larvae by minimizing silk substance spewed out from the larvae.

• Analytical Science and Technology
• /
• v.12 no.4
• /
• pp.306-311
• /
• 1999

Changes of silk protein compositions of average molecular weight (Mw) and free amino acid composition to different solubility conditions were studied by SDS-polyacrylamide electropholesis, gel permeation chromatography (GPC), and free amino acid analysis method. We can not detected average molecular weight distribution of different hydrochloric acid (HCl) conditions as SDS-polyacrylamide method, but as using GPC method, molecular weight distribution of 2N-HCl, 1N-HCl and 0.5N-HCl (3 hrs at $110^{\circ}C$ treated) are confirmed Mw 800, 1,500 and 3,700, respectively. The average molecular weight of calcium chroride and calcium chloride-enzyme treated samples are shown Mw 46,800 and 12,500, respectively. The degree of hydrolysis and the composition of the free amino acid in the fibroin hydrolysates effected significantly composition of free amino acids of the fibroin powder. The increase of the degree of hydrolysis and ratio of free amino acids and oligopeptides were found to be directly related to the concentration of hydrochloric acid and treatment of enzyme, resulting in the increase of water solubility.