• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.3
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• pp.82-90
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• 2009

Disintegration of sewage sludge (SS) was investigated by batch experiments using mechanical pre-treatment. Mechanical disintegration of SS increased the amount of soluble chemical oxygen demand (SCOD), protein and carbohydrate due to the break-up of cell walls. The mechanical disintegration incorporated with alkaline pre-treatment demonstrated higher amount of SCOD compared with mechanical one only. In terms of anaerobic biodegradability, mechanical pretreatment enhanced the anaerobic biodegradation of SS, leading to the methane production improvement. The improvement in BMP for SS treated with mechanical and alkaline-mechanical pre-treatments were 24.1% and 44.5%, respectively. This result suggested that disintegration of SS was effective for improving anaerobic biodegradability.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.145-152
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• 2002

To compare the Carbon metabolic response to high temperature stress in Zoysiagrass [Zoysia matrella (L.) Merr.] and Creeping bentgrass (Agrostis palustris Huds) with respect to heat tolerance, C metabolites were determined from April to September. Sampling was carried out on an established golf course (Muan Country Club, Chonnam, Korea). Shoot mass(g Dry weight per hole cup) of creeping bentgrass started to decrease from June and recovered from August whereas that of zoysiagrass was less varied. Chlorophyll content in creeping bentgrass was significantly higher than zoysiagrass until July, and then decreased by 43% from July to August. Zoysiagrass contained higher soluble sugar than creeping bentgrass throughout experimental period. Soluble sugar in zoysiagrass increased about 58% from April to May, and less varied until August. Soluble sugar in creeping bentgrass slightly increased until July and sharply decreased at August. Starch concentration in zoysiagrass continuously decreased to September after a significant increase from April to May. A remarkable fluctuation in both starch and fluctuation concentration was observed between June and August showing high accumulation for June to July and high degradation for July to August. These results suggest that through creeping bentgrass suffers much severely from high temperature stress than zoysiagrass especially June to August. An active accumulation and degradation in nonstructural carbohydrate in creeping bentgrass during this period might be associated with heat stress.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.490-495
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• 1994

Enzymatic solubilization of tofu-residue was attempted using carbohydrase isolated from Aspergillus niger CF-34. Tofu-residue, by-product of tofu manufacture or soymilk processing was used as the model for plant cell wall. It was found that tofu-residue was rich in nurients: 46.7% carbohydrate, 32.8% protein, the rest being lipid and ashes. Carbohydrate component of tofu-residue consisted of 36.8% cellulose and 62.6% hemicellulose. The carbohydrase was found to consist of pectinase, xylanase, PGase, CMCase, and SFase when tofu-residue and pectin were used as the carbon source. Enzyme induction was maximum at 7days of culture. Optimum reaction pH was 4.0, temperature $50^{\circ}C$. The enzyme was stable to $50^{\circ}C$, above which the stability decreased rapidly.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.83-90
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• 2008

The ultrasonic pre-treatment of sewage sludge (SS) was investigated to increase soluble organic material and to improve anaerobic biodegradability. Ultrasonic disintegration of SS increased the amount of soluble chemical oxygen demand (SCOD), protein and carbohydrate concentrations whereas particle size decreased due to the break-up of cell walls. In terms of anaerobic biodegradability, ultrasonic pre-treatment enhanced the anaerobic biodegradation of SS, leading to the methane gas production improvement. Biochemical methane potential (BMP) of SS was 211.3 ml $CH_4/gVS$ whereas BMP after ultrasonic pre-treatment was 294.3 ml $CH_4/gVS$. The improvement in BMP for SS treated with ultrasonic disintegration was as high as 40 %. This result indicated that disintegration of SS was efficient for enhancing anaerobic biodegradability.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.9-15
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• 2019

This study aimed to examine the effects of different degrees of defoliation during harvest season on hydroponically cultured 'Seolhyang' strawberry's fruit characteristics, plant growth, and changes in nonstructural carbohydrates, and find an effective defoliation method. On November 29, 2013, some of the 'Seolhyang' leaves were non-defoliated and the others were defoliated remaining 9 and 5 leaves. The number of fruits and fruit weight were not significantly different in the first flower cluster but in the second, third, and fourth flower clusters decreased as the level of defoliation increased. The soluble solids content and acidity of fruits decreased in all the clusters as the level of defoliation increased. The leaf area and leaf dry weight of strawberry plant in all the treatment groups decreased from January to March and root dry weight sharply decreased during February. Thereafter, during April, the growth of plant increased. As defoliation increased, the dry weight of fruits, flower clusters, crowns, and roots decreased, and during late growing period, difference in dry weight according to the degree of defoliation was considerable. The content of carbohydrate was greater in the leaves than the fruits excepting January 30 and February 28, 2014 and in the case of strawberry plant that continuously produce fruits, the content of carbohydrate decreased in the leaves and roots. As defoliation increased, the content of carbohydrate in fruits, flower clusters, crowns, and roots decreased. Defoliation for strawberry plants is carefully done during harvest season. Twelve leaves during December and 14 leaves from January to March should be maintained, and in April when the number of leaves increases, old leaves should be defoliated.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.358-362
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• 1984

Soybeans were soaked in water for 3 hrs and germinated at $25^{\circ}C$ for 5 days followed by hot water extraction and boilding for 30 min. The prepared soymilk was analyzed for chemical composition, phytic acid and soluble minerals. Germination resulted in a slow decrease in total solids while protein recovery increased to a maximum of 92.5% after 2 days. Carbohydrate content was reduced to 65% by the 5th day of germination. The intial phytic acid content in soymilk of 1.26g recovered from 100g dry soybean was decreased by 41.3% while inorganic phosphorus increased more than four times from 31.3mg to 135.0mg. Total soluble minerals was also steadily increased.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.7-15
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• 1993

Nitrogenous and non structural carbohydrate compounds in the remaining tissues of 10 weeks old alfalfa (Medicago sativa L.) grown in hydroponic culture, were analysed during 24 days of regrowth following shoot removal. The dry weights of the remaining organs were not significantly changed for 10 days following shoot removal. Compared with uncut plants, defoliation drastically depressed root growth, in particular that of taproot. During 6 days of regrowth, nitrogen contents in all remaning organs significantly decreased. Nitrogen loss in this period was pronounced in root system. Nitrogen contents in each organ after 24 days of regrowth in defoliated plant were recovered completely or exceeded initial level. Amino acid-N was the most readily available form of nitrogen while protein-N was the largest storage pool. The tap root contained about 51.0% and 33.4%, respectively, of the total starch and total ethanol-soluble sugar contents. The starch content of tap roots initially exceeded 40.7 mg. plant$^{-1}$ (day 0), and then declined to the minimum level on day 14. This result clearly showed that the tap root is the major storage site for metabolizable nitrogen (protein-N and amino acid-N) and carbohydrate(starch), and that the degradation of these researves occur much actively in the early period of regrowth.

• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.93-99
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• 1987

Six rice cultivars showing various types of resistance or susceptibility to Pyricularia oryzae in the field were used to study the relationship between susceptibility and contents of carbohydrates, amino acids and phenolics at different plant maturities and leaf ages under controlled environmental conditions. No consistent differences between the susceptible cultivars and adult-plant-resistant cultivars were found in terms of the contents of individual carbohydrates, total amino acids and phenolics in rice leaves throughout the plant development. Only the adult-plant-resistant cultivar Dobong had lower contents of inositol throughout the plant development than the other cultivars. The amounts of sucrose, inositol, glucose, and fructose increased in all tested cultivars at eight leaf stage than those at five leaf stage, but slightly decreased at twelve leaf stage. In contrast, total amino acids and phenolics gradually decreased during plant development. With increasing age of rice leaves, the amounts of total soluble amino acids and phenolics gradually increased in healthy fifth leaf tissues, although there were no significant differences between the cultivars. In particular, a high level of phenolics existed in old fifth leaves of the cultivar Dobong. These results suggest that increased resistance to blast of matured rice plants and old leaves may be the two different phenomina derived from the physiological changes occurring during plant development and leaf senescence, probably functioning differently in P. oryzae development.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.404-410
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• 2014

The effects of treatment with various complex carbohydrases such as Pectinex, Celluclast, Viscozyme, and Ultraflo on the physiochemical properties, polyphenol extraction yields and antioxidant activities of pear peel and pear core were investigated. When pear peel and pear core were treated with complex carbohydrases, the soluble solid content of peel increased, whereas it did not change significantly in the case of pear core. When pear peel and pear core were treated with Pectinex, significant improvement of soluble solid content was observed along with the highest extraction yield of reducing sugar content. Total sugar content increased in most of the enzyme treatment groups. In the case of pear peel, the Viscozyme treatment group showed the highest total polyphenol contents, total flavonoid contents, DPPH radical scavenging activity, ABTS radical scavenging activity, and SOD-like activity. When the flesh and core of pear were treated with Celluclast, total polyphenol contents increased. All enzyme treatment groups except for the Ultraflo treatment group showed increases in total flavonoid contents. With regard to pear flesh, the Celluclast group showed the highest DPPH radical scavenging activity. When pear core was treated with the four complex carbohydrases, DPPH radical scavenging activity and ABTS radical scavenging activity did not increase significantly. However, the SOD-like activity of all enzyme treatment groups significantly increased. Consequently, dry matter and soluble solid contents, polyphenol content, and antioxidant activity of pear peel and core could be improved by complex carbohydrase treatment.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.698-702
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• 1993

Effect of heating temperature on elution patterns of soluble carbohydrate of legume starches and the texture of starch gels was investigated. The elution profiles of soluble carbohydrate obtained by Sepharose 2B-CL showed that the larger molecules were leached as the heating temperature increased. The elution profiles of soluble carbohydrate of cow pea and mung bean starches were similar, but those of kidney bean starch were different. The gel structures of cow pea and mung bean were stable with showing high values in hardness and cohesiveness. But red bean and kidney bean gels were weak in hardness and cohesiveness. As the heating temperature rised, hardness and cohesiveness were increased in gels prepared by heating for 15 min. However, the gels made by heating for 1 hour showed that less hard and more cohesive gels from cow pea and mung bean, while harder and more cohesive gels from red bean and kidney bean were obtained as the heating temperature increased from $85^{\circ}C\;to\;95^{\circ}C$.