• Food Science and Biotechnology
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• v.18 no.6
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• pp.1365-1370
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• 2009

Aspergillus kawachii extracellular pectinases were screened in liquid cultures with different carbon sources. The fungus grown on citrus pectin or lemon pomace produced at least one of these inducible pectinases: acidic polygalacturonase, pectin lyase, pectin methylesterase, $\alpha$-L-arabinofuranosidase, $\alpha$-1,5-endoarabinase, $\beta$-D-galactosidase/exogalactanase, and $\beta$-1,4-endogalactanase. The lemon-pomace filtrates also contained significant $\alpha$-L-rhamnosidase and $\beta$-D-fucosidase activities. Most of the screened pectinases were active at pH 2.0-2.5, indicating that the A. kawachii enzymes were acidophilic. Under the culture conditions employed we could not detect enzymatic degradation of soybean rhamnogalacturonan. The A. kawachii pectinase-production-related regulatory phenomena of induction-repression resemble those described for other Aspergillus sp.

• Microbiology and Biotechnology Letters
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• v.10 no.1
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• pp.45-52
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• 1982

A fungus with the highest protopectinase productivity was selected among 205 strains isolated from the soil and identified as a Verticillium sp. The Verticillium sp. was cultivated on wheat bran and the crude extruct of its culture medium showed the highest protopectinase activity on the following conditions: 3 days of cultivation time, 27$^{\circ}C$ of cultivation temperature, 1.2 $m\ell$/g wheat bran of water content, and reinforcement of ammonium nitrate and calcium chloride at the concentration of 0.5 and 0.02%, respectively. The optimum conditions for pectin production from Citrus peel pulp by the protopectinase were consequently obtained as follows: 20$m\ell$/g of liquid volume-to-pulp weight ratio, 4$0^{\circ}C$ of reaction temperature, and 4 of reaction pH. The higher the enzyme concentration, the better the yield of pectin and the shorter the reaction time. Total 45.6mg of pectin/g peel was produced by 1 hour reaction at the enzyme concentration of 10.5 units/$m\ell$. Molecular weight of the pectin produced by the enzyme was estimated to be about 62,000 by Smit and Bryant's method.

• Journal of Microbiology and Biotechnology
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• v.2 no.4
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• pp.260-267
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• 1992

Pectate lyase from alkalitolerant Bacillus sp. YA-14 is an endo-type pectate lyase which acts randomly at the $\alpha$-1, 4-galacturonan linkage, and requires calcium or strontium ions for its activity. The enzyme is active on low methyl esterified pectin, but the activity toward a high methyl esterified substrate is reduced. The apparent Km's of the enzyme toward sodium polygalacturonic acid, polygalacturonic acid, and various pectins such as apple pectin, citrus pectin, and genu pectin are 0.826 mg/ml, 0.685 mg/ml, and 1.14 mg/ml, respectively. The enzyme activity is inhibited by SDS, urea, and sodium azide, but not by various reducing reagents, such as $\beta$-mercaptoethanol, Na-thiosulfate, Na-sulfate, cystein, and L-ascorbic acid. The enzyme is inactivated by N-bromosuccinimide, $I_2, H_2O_2$. PMSF, and iodoacetate. Judging from the results of their inhibition types, we speculate that tryptophan and serine residues are directly involved in enzyme activity, while tyrosine and methionine residues are indirectly involved in its activity.

• Food Science and Preservation
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• v.15 no.1
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• pp.94-98
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• 2008

To search functional biomaterials of citrus pressed cake, the chemical constituents were analyzed Moisture content of citrus pressed cake varied slightly with sampling time. Moisture, non-nitrogen compounds, crude protein, crude fat, and ash of citrus pressed cake were 82.23% 16.94% 1.27% 2.5%, 0.58% (all w/w) on average, respectively. The chemical composition of citrus pressed cake was more similar to the peel than to the flesh of Citrus unshiu var: miyakawa. The pH, acid content, and pectin content were 3.57, 0.43% (w/w) and 1.49% (w/w), respectively. The vitamin C content of peel of Citrus unshiu var. miyakawa was 87.1mg/100g, and was higher than the 46.4mg/100g of citrus pressed cake. Total carotenoids of citrus pressed cake, and the peel and flesh of Citrus unshiu var. miyakawa, were 512.2mg/kg, 2,649.5mg/kg, and 199.4mg/kg, respectively. Therefore, citrus pressed cake may be utilized as a natural source of pectin, flavonoids and carotenoids. The major inorganic elements of citrus pressed cake were 201.3mg/100g of K, 47.9mg/100g of Ca, 19.4/100g of P, and 17.8/100g of Mg. The major free sugar contents of citrus pressed cake were 3.05% (w/w) fructose, 2.91% (w/w) glucose, and 4.94%(w/w) sucrose. Total free sugar was 9.91% (w/w), corresponding to 58.5% of 1be non-nitrogen compounds. The main flavonoids of Citrus unshiuwere narirutin, hesperidin, and rutin. Neohesperidin and hesperetin were also detected in trace amounts. Themajor flavonoids of citrus pressed cake were hesperidin and narirutin, and the content of hesperidin was 194.6mg/100g.

• Journal of Nutrition and Health
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• v.30 no.2
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• pp.210-219
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• 1997

Retarding effects of the dietary fibers from tangerine peels on glucose, bile acid and cadmium transport were evaluated by dialysis method, and were compared with those of commercial dietary fibers(citrus pection, CM-cellulose, guar gum, $\alpha$-cellulose). Yields of total (TDF), insoluble(IDF) and soluble dietary fibers(SDF) from tangerine peels on the fresh matter basis were 2.84%, 1.95% and 0.39% respectively. The amount of insoluble fibers was 5.2 times higher than that of soluble fibers. Soluble fibers(guar gum, CM-cellulose, SDF, pectin) had the retarding effect on glucose transport, while IDF, TDF and $\alpha$-cellulose did not have. Guar gum showed the greatest effect, followed by CM-cellulose, SDF and pectin. Among the extracted fibers, only SDF had the effect on glucose transport retardation. Regarding bile acid dialysis, guar gum had the greatest retarding effect, and all dietary fibers from tangerine peels, especially SDF, showed the effect of bile acid retardation. On cadmium transport retardation, CM-cellulose had the greatest effect, followed by SDF, TDF, IDF, guar gum and pectin. Among the extracted fibers, SDF had the greatest effect on Cd trasport transport retardation. The extracted dietary fibers showed higher retarding effect on Cd transport than glucose and bile acid transport, and the effect of SDF was higher than IDF.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.163-168
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• 1994

Erwinia rhapontici causes soft-rot disease in a number of plants such as rhubarb, onion, hyacinth and garlic. Pectate lyase (Pel) depolymerizes pectin and other polygalacturonates, which is though to play a role in bacterial invasion of plants. Pel activity was not detected in E. rhapontici cultured in a minimal salts medium containing glycerol, polygalacturonate, or citrus pectin as a carbon source. However, when sterilized potato tuber and Chinese cabbage slices were added to minimal salts polygalacturonate (0.5%) medium, E. rhapontici produced pectate lyase enzyme. Also Pel activity was consistently detected from macerated potato tubers, Chinese cabbage leaves, lettuce leaves and celery petioles tissue. Pel in the extract of macerated Chinese cabbage caused by E. rhapontici strain 1, resulted in electrolyte loss, tissue maceration and cell death of potato tuber tissue. These results indicate that E. rhapontici produces pectate lyase only in the presence of non-diffusible plant components, and that this enzyme probably contributes to its pathogenicity.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.1
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• pp.75-85
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• 2016

Pectin, a naturally occurring polysaccharide, has in recent years attracted considerable attention. Its benefits are increasingly appreciated by scientists and consumers due to its safety and usefulness. The chemistry and gel-forming characteristics of pectin have enabled to be used in pharmaceutical industry, health promotion and treatment. Yet, it has been rarely used in cosmetics because of its incompatibility with many cosmetic ingredients, including alcohols, and unstable viscosity of pectin gels under various pH and salt conditions. However, low-molecular-weight pectin oligomers have excellent biological activities, and depolymerization of pectin to produce cosmetic ingredients would be very useful. In this study, we attempted the development of cosmetic ingredients using pectin with an excellent effect on human skin. We developed a bio-conversion process that uses enzymatic hydrolysis to produce pectin hydrolysates containing mainly low-molecular-weight pectin oligomers. Gel permeation chromatography was used to determined the ratio of hydrolysis. The molecular weight of the pectin hydrolysates obtained varied between 200 and 2,700 Da. The two newly developed low-molecular-weight pectin hydrolysates, LMPH A and B, had higher anti-oxidative activities than pectin or D-galacturonic. Exposure to UVB radiation induces apoptotic cell death in epidermal cells. Annexin V binding and propidium iodide uptake were measured by flow cytometry to evaluate UVB-induced cell death in HaCaT cells. Both LMPH A and B reduced UVB-induced cell death and increased cell proliferation by 22% and 30% at 0.5% concentration respectively, while pectin had no significant activity. In conclusion, this study suggests that the newly developed low-molecular-weight pectin hydrolysates can be used as safe and biologically active cosmetic ingredients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.108-114
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• 2021

Green colored citrus is the immature fruit of the field citrus crop in Jeju, and its demand has been growing recently as it is known to contain a large amount of carotinoid, pectin, and vitamin C. It differs from the traditional varieties of blue tangerine, which are green in February and turn in yellow in March-April. This study analyzed the effects of the increased demand in green citrus on the field citrus industry. For our analysis, a partial equilibrium supply-demand model was established with a dynamic recursive structure using data from 1989-2017. Model calibration was also conducted to determine the best supply-demand model and then, the impacts of increasing demand for green immature citrus in Jeju for 2018-2030 was simulated. The simulation results show that there is no significant impact on the producing area prior to 2022, but there is a distinguishable increase of 18ha in 2023, 52ha in 2025, and 142ha in 2030. It was also predicted that revenue would increase by KRW 7.75 billion on average from 2021-2030.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.229-243
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• 1997

This study was performed to investigate the effects of dietary fibers from tangerine peels on lipid and cadmium metabolism. And effects were compared with those of commercial dietary fibers($\alpha$-cellulose, citrus pectin). Sixty male rats of Sprague-Dawley strain weighing 186.7$\pm$2.6g were blocked into 12 groups according to body weight, and were raised for 2 weeks. Cadmium chloride was given at the levels of 0 of 400 ppm in diet. Various dietary fibers were given at the level of 0 or 4%(w/w) of diet. The results are summarized as follow. In lipid metabolism, insoluble fibers[insoluble dietary fibers from tangerine peels(IDE), $\alpha$-celluolse] increased fecal excretion of lipids by inhcreasing feces weight, and decreased the concentrations of serum triglyceride and liver lipids. Soluble dietary fibers from tangerine peels(SDF) decreased the concentrations of serum cholesterol and liver lipids by increasing fecal lipids, too. In cadmium metabolism, soluble fivers(SDF, pectin) inhibited Cd absorption by increasing fecal Cd excretion and decreased Cd concentrations of intestion, liver and kidney. In conclusion, among the extracted fibers, SDF were more effective on lipid and Cd lowering activity and IDF had effect of increasing fecal lipid excretion. This result is useful to reduce food waste and utilize waste products.

• Applied Biological Chemistry
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• v.9
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• pp.97-104
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• 1968

A survey of the free amino acids and free sugars in the juice of fourteen citrus varieties was made by means of paper chromatography and the pectin content in the rind was detected The results of the survey are summarized as follows. 1) Sixteen aminoacids detecteu in fourteen varieties under the condition of this study were distributed with. different frequency as follow. Proline, gamma-amino-butyric acid, alanine, valine, serine, glutamic acid, aspartic acid (in 14 varieties), lysine(12), leucine threonine(11), isoleucine(10), arginine(9), glycine(6) ${\beta}-alanine$(4) asparagine(3) unknown(2). 2) Proline, gamma-amino-butyric acid were mostly abundant in all varieties and alanine was next in the amount. 3) The varieties in the decreasing order of number of amino acids container were C. grandis madow C. leiocarpa (14 acids), C. sulcata, C. hassaku. native citron, Fortunella japonica(13) C. grandis heiko, C. Tamurana iyo, C. nobilis(12) C. reticulata C. junos(11) C. natsudaidai(10) C. miyakawa unshiu, C. ohali unshiu(9). 4) The varieties which appear to contain all essential amino acids(6 acids)detected were C. grandis madow C. grandis heiko, C. sulcata, C. Tamurana iyo, C. hassaku and native citron, and C. natsudaidai, C. unshiu were the least (1-3 acids). 5) Glucose fructose, sucrose and maltose were detected in all varieties. 6) The pectin content in the rind ranged from 8.64% F.W.(C. junos) up to 17.0% for C, grandis madow and the mean was $11.63{\pm}2.69%$.