• Food Science and Preservation
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• v.11 no.4
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• pp.485-490
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• 2004

Crude corn oil (CCO) was obtained through the expression-extraction process from corn germ. The CCOs of final process at $90^{\circ}C,\;70^{\circ}C\;and\;50^{\circ}C$ were stored in outdoor storage tanks. From the samples, refined CCO (RCCO) were prepared with $0\%,\;10\%\;and\;20\%$ excessive of phosphoric acid, caustic solution and acidic clay were used in degumming-alkali refining-bleaching process. RCCOs were stored at room temperature in dark places. The color change was not effected by the amount of phosphoric acid, caustic solution and acidic clay, but temperature of process affects the color change. Finally, the prevention for color reversion of RCCO could be obtained by lowering the temperature of final process and optimal temperature of RCCO in summer was found about less than $50^{\circ}C$.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.2
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• pp.265-268
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• 2009

Wild silkmoths can be utilised sustainably in the production of silk as an income for resource-poor rural communities. However, attack by parasitoids and predators affect the quality of cocoons and quantity of raw silk produced. A laboratory experiment was undertaken to quantify the effect of parasitoids' (dipteran and hymenopteran) and predators' (ants) exit and ingress holes, respectively, on silk production. The mean number of shells required to produce fifty grams of raw silk was highest with cocoons parasitised by a dipteran and lowest with unattacked cocoons (but with moths already emerged). Degumming loss was highest in parasitised and lowest in unttacked cocoons, but both were not different from cocoons predated by ants. Shell weight was highest in unattacked cocoons, followed by hymenopteran-parasitised and predated cocoons, with the dipteran parasitized ones being the least. Single cocoon weight was greater in hymenopteran-parasitised and predated cocoons than the dipteran-parasitised and unattacked cocoons. Shell ratio or raw silk, floss and yarn weights were higher in unattacked than parasitised and predated cocoons. The total loss in raw silk attributable to attack by parasitoids and predators ranged between 17.4~31.2%. The results offer baseline information for assessment of economic losses in wild silk farming due to parasitoids and predators in the field.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.67-72
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• 1987

This study was carried out for the optimum predegumming in the protease degumming process of silk fabrics by ocmparing the physical properties of silk fabrics degummed with different weight losses of predegumming. 1. In twill habutai, the stiffness of fabric was reduced and the smoothness was improved with increasing weight loss of predegmming, however, the soft feeling value which means the total handle value of medium fabric for lady, was maximum at 20% of predegumming weight loss. 2. In the case of crepe de chine representing thin fabric for lady, the anti-drape stiffness was relatively increased with 22% weight loss of predegumming. However, the other physical properties, such as the flexibility with soft feeling were less related to the degrees of predegumming.

• Journal of Sericultural and Entomological Science
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• v.43 no.1
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.150-157
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• 1998

This study was carried out to define the effects of anti-juvenile hormone analogue(AJH) treatment at different silkworm larval stages on some silk filament properties. It was revealed that the treatments at the 1st and 2nd days of the 3rd instar as well as the 1st day of the 4th instar resulted to trimolters induction without lethal effect. The trimolters induced by treatment at the 1st day of the 4th instar showed the shortest larval duration and the lowest single cocoon weight, cocoon shell ratio, cocoon size, single filament length and denier of filament compared with those of the control, while the trimolters induced by the 3rd-instar treatment showed intermediate values. All treatments showed no significant differences from the aspect fo degumming ratio, elongation rate and crystallinity index of fibroin. However the silk filament obtained from the treatment at the 1st day of the 4th instar showed the highest tenacity which was revealed to be related to the better uniformity of filament by the means of microscopic photographing. FT-IR spectroscopy of the silk fibroin showed a sharp and strong peak at the position of 794.72 cm-1 in all AJH-treated samples regardless of trimolters induction, which was absent in control.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.63-71
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• 2012

The objectives of this study were to investigate the antioxidant activity of Schizandra chinensis seed oil and its active ingredients. Schizandra chinensis seed oil content extracted with hexane was 36.06%. Schizandra chinensis seed oil extracted with hexane was purified during 20 min at $85^{\circ}C$ with phosphoric acid 0.15% for degumming and 20 min at $80^{\circ}C$ with 3 M NaOH 1% for deaciding. The purified oil consisted of unsaturated fatty acid (88.7%), fatty acid (9.97%), and so on. The major unsaturated fatty acids of purified oil were linoleic acid (71.1%) followed by oleic acid (15.7%), while the main saturated fatty acid was palmitic acid (6.56%). The purified oil was found that contents of phenolic compounds, vitamin A, and E were 1.45 g/100 g, 1494.86 RE/100 g, and 0.58 mg ${\alpha}$-TE/100 g, respectively. Schizandra chinensis seed oil exhibited strong antioxidant activity (91.7%) as compared to grape seed oil and canola seed oil with 87.4% and 85.1% in the DPPH assays. Present results suggest that Schizandra chinensis seed oil could be potentially used as bioactive source for health and preventing numerous diseases.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.43-47
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• 1993

Using the new scouring soap made from rapeseed oil, various scouring test was done souring effects of new scouring soap were estimated. In the effects of scouring soap on the degumming ratio, OS (the soap made from oleic acid) was the most excellent and the next was RS (the soap made from rapeseed oil). Both OS and RS were more excellent than MS (the soap on the market). In a buffer power of soap solution, OS and RS were good, but MS was poor. The uneven dyeing was not observed in the silk fabric degummed by OS and RS, but observed in silk fabric degummed by MS. The value of tenacity and elongation in the silk degummed by OS and RS was higher that degummed by MS. In the crease recovery, softness and whiteness, the order of value was OS, RS, MS.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.132-139
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• 2010

Sericin pulverization process was applied by freezing-thawing of sericin protein concentration solution and physicochemical properties of sericin/chitosan blended films were investigated. In sericin pulverization process by freezing-thawing method, the refrigeration storage at $4^{\circ}C$ maximized gelling between sericin molecules, which increased 10% of recovery ratio from sericin concentration solution that using ultrafiltration procedure. In physicochemical properties of sericin/chitosan blended films, the maximum load of chitosan (6.7kgf) had higher than that of sericin (1.2kgf), and the elongation of sericin and chitosan had 96% and 34%, respectively. Also FT-IR analysis of sericin/chitosan blended films showed that both sericin and chitosan films had amide I peak (N-H bond) in $1,521cm^{-1}$ and amide II peak (C=O bond) in $1,630cm^{-1}$. In addition, it could confirm compatibility between both materials as indicated by the decrease in the amide I peak's absorption value as chitosan content increases.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.15-20
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• 1997

Changes in antioxidative substances-sesamol, sesamin and sesamolin - and mineral contents of sesame oil during refining processes have been studied to investigate the oxidative stability of oils during the storage at $70^{\circ}C$. Fe, Cu, Mg and Zn were nearly removed from the oil by the degumming process. During storage, the changes of total volatile contents in crude and degummed sesame oil were not noticeable but those in alkali-refined and deodorized sesame oil were increased at early period of the storage. The increases of hexanal and pentanal were most noticeable and their concentration was increased markedly in alkali-refined, bleached and deodorized sesame oil at early period of the storage. During refining processes and storage, sesamin was relatively stable but the content of sesamolin was decreased. The content of sesamol was decreased until alkali-refining process but increased during a bleaching process. The content of sesamolin tended to decrease with increasing of sesamol during storage.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1244-1251
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• 2020

Phospholipase A₂ (PLA₂) from Streptomyces violaceoruber is a lipolytic enzyme used in a wide range of industrial applications including production of lysolecithins and enzymatic degumming of edible oils. We have therefore investigated expression and secretion of PLA₂ in two workhorse microbes, Pichia pastoris and Escherichia coli. The PLA₂ was produced to an activity of 0.517 ± 0.012 U/ml in the culture broth of the recombinant P. pastoris. On the other hand, recombinant E. coli BL21 star (DE3), overexpressing the authentic PLA₂ (P-PLA₂), showed activity of 17.0 ± 1.3 U/ml in the intracellular fraction and 21.7 ± 0.7 U/ml in the culture broth. The extracellular PLA2 activity obtained with the recombinant E. coli system was 3.2-fold higher than the corresponding value reached in a previous study, which employed recombinant E. coli BL21 (DE3) overexpressing codon-optimized PLA₂. Finally, we observed that the extracellular PLA₂ from the recombinant E. coli P-PLA₂ culture was able to hydrolyze 31.1 g/l of crude soybean lecithin, an industrial substrate, to a conversion yield of approximately 95%. The newly developed E. coli-based PLA₂ expression system led to extracellular production of PLA₂ to a productivity of 678 U/l·h, corresponding to 157-fold higher than that obtained with the P. pastoris-based system. This study will contribute to the extracellular production of a catalytically active PLA₂.