• Journal of the Korean Society of Food Culture
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• v.11 no.5
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• pp.683-687
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• 1996

Jujube paste was prepared by autoclaving the fresh jujube at 1.2 atm and $120^{\circ}C$ for 30 min and removing the skin and cores. In order to increase the juice yield, the paste was treated with pectinase, cellulase and their combinations. The soluble fractions of enzymatically treated jujube paste were characterized in terms of yield, pH, titratable acidity, color, Bx, transmittance and sugar compositions. The original paste exhibited the water soluble fraction of 57.3%. Of various quality factors, the clarity was the most significantly distinguished between pectinase and cellulase treatments. The cellulase treatment produced the cloudy juice with the yield of 83.60%. On the other hand, the clear juice was produced by the pectinase and combined treatments due to degradation of pectins, whose yields were 79.47% and 85.39%, respectively. The results clearly demonstrated that the pectinase treatments improved the solubilization efficiency and clarity.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.59-68
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• 2013

The cotton contains various impurities such as protein, wax, pectins, coloring matter, even though cotton has been a major source of pure cellulose. The purification processes have been commonly applied to obtain the pure cellulose. However the excessive purification treatments could lead to the damage in the cellulose structure which could result in the degradation of cellulose and the limited application of cotton cellulose. In this study, the changes in cellulose structural properties such as crystallinity and DP(degree of polymerization) by the various conditions of the purification processes were investigated. The less toxic agents such as hydrogen peroxide and sodium silicate were applied for the purification treatment in this study. The increase in the process times, the temperature and the applied amount of chemical agents resulted in the more purified cellulose. The DP of cotton cellulose was increased at the first weak conditions by the reduction of small molecules such as pectin, wax, and so on. Especially the 2 % addition amount of $H_2O_2$ with $Na_2SiO_3$ resulted in the higher value in the DP and the brightness compared to the 1.5 % addition amount of $H_2O_2$. However, the 4 % addition amount of $H_2O_2$ with $Na_2SiO_3$ showed the decreased value because of excessive treatment. In case of the changes in the crystallinity (Gjk), the highest value of the crystallinity was obtained by the 2% addition amount of $H_2O_2$ on the cotton cellulose, which showed similar with the change in the DP.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.153-156
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• 2000

Xylan, the major hemicellulose component of many plants, occurs naturally in a partially acetylated form and lignin, the most resistant component in plant cell wall degradation, is also attached to ${\beta}-1,4-linked-D-xylose$ backbone through the ester linkage. Esterases are required to release the esterified substituent and acetyl esterases are important in the complete degradation of acetylated polysaccharides, like pectins and xylans. The gene(Axe) encoding acetyl xylan estarase(AXE) was isolated from genomic ${\lambda}$ library from Aspergillus ficuum. Nucleotide sequencing of the Axe gene indicated that the gene was separated with two intervening sequences and the amino acid sequence comparison revealed that it was closely related to that from A. awamori with the 92 % indentity. Heterologous expression of AXE was conducted by using YEp352 and Saccharomyces cerevisae 2805 as a vector and host expression system, respectively. The Axe gene was placed between GAL1 promoter and GAL7 terminator and then this recombinant vector was used to transform S. cerevisiae 2805 strain. Culture filtrate of the transformed yeast was assayed for the presence of AXE activity by spectrophotometry and, comparing with the host strain, four to five times of enzyme activity was detected in culture filtrate of transformed yeast.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.420-427
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• 1991

The structure of fresh, salted and heated petiole tissue from Chinese cabbage was examined with optical microscope, and the pectin of the tissues was fractionated by successive extraction. The pectin in Chinese cabbage consisted mainly of high methoxyl pectin(pA) and low methoxyl pectin(pB). The pA content was converted to pB markedly by salting and heating at $60{\sim}70^{\circ}C$ for 30 min while heating the cabbage above 80 decreased pB content. The firmness of heated tissue was highly correlated with pB content(r=0.996). Cytorrhysis test showed that pore size of the tissue became smaller by salting and heating at temperature below $80^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.15 no.1
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• pp.57-66
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• 2010

Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.68-73
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• 1999

In order to overcome same disadvantages of acidic solubilization of pectin from apple pomace, enzymatic selective solubilization with exo-polygalacturonase was developed. According to analyses of the effects of temperature, pH and reaction time on extraction yield, the maximum yield by the enzymatic method, shown under the extraction condition of $45^{\circ}C$, pH 7 and 60 hours, was 31.0%, whereas the yield from an acidic method was 8%. Also the quality of pectin extracted by the enzymatic method was to that from acidic solubilization. The purity and methoxyl content of enzyme-extracted pectin were 80.1% and 6.36%, respectively, which were higher than 75.7% and 2.44% of acid-solubilized pectin. Viscosity average molecular weights of enzymic extracted and acid solubilized pectins were $1.50{\times}10^4\;and\;7.66{\times}10^4$, respectively.

• Korean Journal of Agricultural Science
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• v.41 no.1
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• pp.9-16
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• 2014

This experiment was conducted to examine the effects of a short-term treatment of high pressure $CO_2$ on shelf-life of strawberry fruit. A short-term treatment (12 hr) of 100% $CO_2$ resulted in the increase of fruit firmness up to 71.9% compared to that at harvest. The firmness of $CO_2$ treated fruit remained a significantly higher than that of control (air) up to 15 days. The alteration of pectic polymers was observed by $CO_2$ treatment such as an increase of EDTA soluble pectins and decrease of water soluble ones. The $CO_2$ treatment resulted in the increase of total amount of wall bound calcium. Pectate lyase activity, an important agent of strawberry fruit softening, was also significantly reduced by $CO_2$ treatment. Contents of soluble solids and acids of $CO_2$ treated fruit were higher than those of control fruit. Short-term treatment of high pressure $CO_2$ affected shelf-life through firmness increase whereas the visual quality and decay incidence of strawberry fruit were not affected.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.254-258
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• 1999

The distribution of anionic groups in the fibers, the fines, the colloidal fraction and the dissolved fraction, respectively, of thermomechanical pulp (TMP) suspensions was determined and peroxide bleaching of spruce TMP were also studied. Spruce TMP was extracted with hexane, treated with alkali, or bleached with peroxide. Suspensions made at pH 5.5 were fractionated into long fibres, large fines, small fines, a colloidal fraction and a dissolved fraction. The charge of the fractions was determined using polyelectrolyte titration. To determined the origin of the charges, the contents of fatty acids, resin acids and acidic units in hemicelluloses in the different fractions were determined by has chromatography. Extraction of TMP with hexane prior to fractionation increased the measured charge of the fibres. The removal of the wood resin probably uncovered some carboxyl groups on the fibre surfaces, or improved th e penetration of polybrene into the pores of the fibres. The charge of the fines and the colloidal fraction was lower when the wood resin had been removed. Alkaline treatment of the TMP increased the charge of the fibres and fines, mainly because of demethylation of pectins. Alkaline treatment increased the charge also of the dissolved fraction, because of the release the charge also of the dissolved fraction, because of the release of pectic acids into the water phase. Alkaline peroxide bleaching further increased the charge of fibres and the dissolved fraction, most likely because of lignin oxidation. The charge of the colloidal fraction, consisting mainly of wood resin, was only slightly affected by alkaline treatment and peroxide bleaching. The anionic groups in TMP suspensions were mainly free uronic acids in the hemicelluloses. The contribution from the fatty and resin acids was substantial only for the colloidal fraction.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1386-1398
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• 2010

Soybean contains a high concentration of carbohydrates that consist mainly of non-starch polysaccharides (NSP) and oligosaccharides. The NSP can be divided into insoluble NSP (mainly cellulose) and soluble NSP (composed mainly of pectic polymers, which are partially soluble in water). Monogastric animals do not have the enzymes to hydrolyze these carbohydrates, and thus their digestion occurs by means of bacterial fermentation. The fermentation of soybean carbohydrates produces short chain fatty acids that can be used as an energy source by animals. The utilization efficiency of the carbohydrates is related to the chemical structure, the level of inclusion in the diet, species and age of the animal. In poultry, soluble NSP can increase digesta viscosity, reduce the digestibility of nutrients and depress growth performance. In growing pigs, these effects, in particular the effect on gut viscosity, are often not so obvious. However, in weaning piglets, it is reported that soy oligosaccharides and soluble NSP can cause detrimental effects on intestinal health. In monogastrics, consideration must be given to the anti-nutritive effect of the NSP on nutrient digestion and absorption on one hand, as well as the potential benefits or detriments of intestinal fermentation products to the host. This mirrors the needs for i) increasing efficiency of utilization of fibrous materials in monogastrics, and ii) the maintenance and improvement of animal health in antibiotic-free production systems, on the other hand. For example, ethanol/water extraction removes the low molecular weight carbohydrate fractions, such as the oligosaccharides and part of the soluble pectins, leaving behind the insoluble fraction of the NSP, which is devoid of anti-nutritive activities. The resultant product is a high quality soy protein concentrate. This paper presents the composition and chemical structures of carbohydrates present in soybeans and discusses their nutritive and anti-nutritive effects on digestion and absorption of nutrients in pigs and poultry.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5265-5271
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• 2015

Background: The effects of plant products on cancer cells has become a field of major importance. Many substancesmay induce apoptosis in anti-cancer treatment. Pectins, a family of complex polysaccharides, and their degradation products may for exasmple exert apoptotic effects in cancer cells. Apples and citrus fruits are the main sources of pectin which can be applied for anti-cancer research. The present study concerned an intact form of pectic-oligoshaccharide named pectic acid (poly galactronic acid). Materials and Methods: Inhibition of cell proliferation assays (MTT), light microscopy, fluorescence microscopy (acridin orange/ethidium bromide), DNA fragmentation tests, cell cycle analysis, annexin PI and Western blotting methods were applied to evaluate apoptosis. Results: The results indicated that pectic acid inhibited cell growth and reduced cell attachment after 24h incubation. This did not appear to be due to necrosis, since morphological features of apoptosis were detected with AO/EB staining and cell cycling was blocked in the sub-G1 phase. Annexin/PI and DNA fragmentation findings indicated that apoptosis frequency increased after 24h incubation with pectic acid. In addition, the data showed pectic acid induced caspase-dependent apoptosis. Conclusions: These data indicate that apple pectic acid without any modification could trigger apoptosis in MDA-MB-231 human breast cancer cells and has potential to improve cancer treatment as a natural product.