• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.88-88
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• 2018

Coffee is one of the most popular drinks in the world. Roasting process of coffee bean is one of major steps to make coffee, however, there are few studies which analyzed chemical compounds in intermediate state of roasting coffee beans due to technical limitations to get coffee beans with the same roasting condition. We utilized Stronghold S7 pro roasting machine which guarantees the saming roasting conditions repletively with the aid of precise computer to control heat sources to get 20 steps (every 30 seconds) of roasted coffee beans during roasting process (10 min in total). Along with roasting process, phenolic compounds were decreased, which can be explained that roasting process cause phenolic compounds degradation. Caffeine is almost constant during roasting, reflecting that caffeine is not affected in roasting process. These samples presents that organic acids significantly increase along with the roasting process by HPLC analysis. With additional analysis of coffee beans, such as moisture contents, pH, as well as coffee tastes, our analysis will show detailed process of chemical compounds of coffee beans during roasting process.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.33-40
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• 1998

The phenolic acids in needles of five pine species such as Pinus densiflora, P. thunbergii. P. virginiana. P. rigida. and P. koraiensis were analyzed seasionally (March, June, September and December) in order to investigate the resistant factors against pine gall-midge(Thecodiplosis japonensis Uchida et Inouye). The interrelation of resistance to pine gall-midge and the content of phenolic acids in pine needles was investigated in the artificial hybride pine species. The contents of salicylic acid in susceptible species (P. densiflora and P. thunbergii) to pine gall-midge which watered with salicylic acid solution in a pot was determined. The results can be concluded as follows, 1. There was a little change in total phenolic constituents of resistant and susceptible pines seasonally. The each content of benzoic acid, salicylic acid and p-hydroxybenzoic acid in June was the highest through four seasons. 2. In June, resistant species showed higher content of salicylic acid than susceptible species, while the content of gallic acid was the highest in December. 3. Among the 21 artificial hybrids(P. densiflora ${\times}$ P. virginiana. P. thunbergii ${\times}$ P. virginiana), the hybrides of the higher salicylic acid content showed the lower rate of pine gall formation. 4. Pine gall formation of the susceptible species which were watered with salicylic acid solution remarkably decreased.

• Journal of Korea Foresty Energy
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• v.22 no.3
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• pp.11-19
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• 2003

Allelopathic effects of black locust(Robinia pseudoacacia L.) was evaluated through germination tests using 13 different species including R. pseudoacacia itself. The water extract from leaf or root of R. pseudoacacia was separately tested. Seed germination of several species was inhibited in the presence of leaf or root extract, although the level of germination was in a wide range depending on the species. Seed germination of R. pseudoacacia was suppressed by 30 % in its leaf extract. Among tested tree species, Hibiscus syriacus and Alnus frma showed significantly inhibited germination in the root extracts whereas Thuja orientalis exhibited germination inhibition in the leaf extract. HPLC was carried out to identify allelochemicals in extracts of leaf and root using eight authentic phenolic compounds that are known to be responsible for allelopathy. The major phenolic compounds occupying about 40 % of total phenolic acids were gentisic acid in leaves and vanillic acid and syringic acid in roots. The leaves contained 7 times more phenolic acids than the roots. Among 8 tested phenolic compounds vanillin was detected only in roots and coumaric acid in leaves. Consequently, 3 out of 13 species showed significantly inhibited germination due to leaf or root extract. This germination test indicates that the inhibitory allelopathic effect by R. pseudoacacia is caused by chemical interaction not by nutritional competition and that the allelochermicals of black locust act species-specifically. No specific influence of the total amount of phenolic compounds on the allelopathic inhibitory germination and the synergic effect by each phenolic compound may play a role for the allelopathic effect by R. pseudoacacia.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.144-155
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• 1987

Water extracts of polygonum hydropiper and Polygonum aviculare completely inhibited the germination of lettuce seeds. Methanol extracts from these two species also inhibited the seed germination of lettuce (Lactuca sativa) and Oenothera odorata. Fifteen phenolic acids in total were identified by GLC from P. hydropiper and eighteen from P. aviculare. The most common phenolic acids identified from P. hydropiper were sinapic, salicylic+vanillic and ferulic acid presented in all the fractions. In addition, salicylic+vanillic, tannic+gallic, sinapic, ferulic and p-coumaric acid seemed to be important phenolic compounds in terms of quantity. However, salicylic+vanillic acids were the unique phenolic acids occurred in all the fractions of P. aviculare. The others such as tannic+gallic, sinapic, ferulic, p-coumaric acid, p-cresol and catechol present in large amount appeared also the important phenolic substances influencing allelopathic effects of P. aviculare. Linolenic acid and oxalic acid were the major fatty and organic acids in both plant species, presented in 2.38mg/g and 20.588mg/g in P. hydropiper, 3.70mg/g and 14.288mg/g in P. aviculare, respectively, which seem to be exhibiting allelopathic effects of these plants. Total alkaloids were presented in low amount such as 0.20% in P. hydropiper arid 0.22% in P. aviculare which may not be important elements. Pet. ether extracts were 2.42% in P. hydropiper and 1.65% in P. aviculare, which exhibit another potential for allelopathic effects that need further investigation. Various authentic phenolic compounds at different concentrations inhibited the germination of lettuce seed, indicating that the phenolic substances identified here may be directly related to biologically active substance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.137-142
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• 2007

This study was carried out to observe the antioxidant and angiotensin converting enzyme (ACE) inhibitory activity of susijang (Korean traditional fermented soy food). The antioxidant activity of susijang was measured by using TEAC (trolox equivalent antioxidant capacity) assay. In addition contents of isoflavones, phenolic acids and amino acids were determined. TEAC values of chungkukjang and susijang were significantly higher than those of yellow soybean (p<0.05). The contents of isoflavones (genistein, daidzein) were found to be significantly higher in chungkukjang and susijang than yellow soybean. The susijang showed high content of free amino acids and phenolic acids. ACE inhibitory activity of susijang was significantly higher than those of chungkukjang and yellow soybean, particularly of 70% ethanol extract.

• Food Science and Preservation
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• v.21 no.2
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• pp.206-214
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• 2014

In this study, the characteristics of alcohol fermentation using Elaeagnus multiflora juice were studied under static fermentation condition in an effort to develop new types of functional wine. After 9 days of fermentation at $25^{\circ}C$, the pH, soluble solids, reducing sugar, viable cell numbers, and alcohol contents were shown to be 3.32~3.33, $7.8{\sim}9.0^{\circ}C$, 29.84~31.05 g/L, 7.26~8.73 cfu/mL, and 11.0%, respectively. The heat treated juice exhibited significantly higher antioxidant activity than untreated juice while the soluble phenolic and flavonoid contents became higher. Also, the fermented wine after the heat treated at $120^{\circ}C$ for 30 min contained free sugar such as fructose (0.42 g/L) and glucose (0.09 g/L), major organic acids such as lactic acid (7.32 g/L), malic acid (2.59 g/L), succinic acid (2.16 g/L), and oxalic acid (3.08 g/L), and major flavanols and phenolic acids such as catechin (99.45 mg/L), epicatechin (264.55 mg/L), epigallocatechin (82.19 mg/L), gallic acid (6.44 mg/L), and salicylic acid (60.53 mg/L). In addition, DPPH radical and ABTS radical scavenging activities and FRAP assay results were 70.47%,, 65.93%, and 1.254, respectively. These results suggest that it is possible to produced a new type of wine using Elaeagnus multiflora fruits.

• Korean Journal Plant Pathology
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• v.3 no.1
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• pp.3-7
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• 1987

Ethanol-soluble amino acids and phenolics in healthy and blast-infected leaves of the susceptible rice cultivar Nakdong and adult-plant-resistant cultivar Dobong were quantitatively analyzed, At the 3 days after inoculation, the levels of soluble amino acids and phenolics in the infected fifth and eighth leaves of the two cultivars ere similar to those of comparable healthy controls. As blast lesions appeared on the leaves at the 5 days after inoculation, the soluble amino acids and phenolics began to increase. At the 7 days after inoculation, the levels of amino acids and phenolics were about 1.5-3 times more than those in healthy controls at the five-and eight leaf stages. The adult-plant-resistant cultivar Dobong showed higher amounts of soluble amino acids and phenolics in both healthy and infected fifth and eighth leaves than did the susceptible cultivar Nakdong, although Dobong was less infected by Pyricularia oryzae than Nakdong, The pronounced increases in amino acids and phenolics in rice leaves of the cultivar Dobong during the blast infection may play an important role in the expression of adult-plant resistance to blast.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.792-798
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• 1994

In order to investigate the antioxidant activity of phenolic compounds contained in domestic Meju and Doenjang , the methanolic extract from defatted Meju and Doenjang was fractionated into the phenolic acid and the isoflavone fractions by alumina column and polyamide-6 column chromatography, respectively. Both phenolic acid and isoflavone fractions exhibited an identical antioxidative effect against the oxidation of linoleic acid. GC analysis revealed that the phenolic acid fractio contained vanillic , chlorogenic ,p-coumalic , ferulic, and caffeine acid. The content of caffic acid was greater than 70% in the phenolic acid fraction and the content of vanillic and chlorogenic acids were disappeared during fermentation, and thus, the facts are thought to be reasons for the low antioxidant activity of the phenolic aicd fraction from Doenjang. Similarly, the isoflavone fraction cotained daidzin, glycitin-65-0 glucosider and genistin and their aglycons such as daidzein, glyciten and genistein. The content of daidzin and genistin in Meju dramatically decreased at the early stage of fermentation ,whereas the content of daidzein an dgenistein rather increased ; however, these change in isoflavone contents did not affect the antioxidant activity of isoflavone fractions.

• Journal of Ginseng Research
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• v.24 no.2
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• pp.64-67
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• 2000

This study was carried out to investigate the possible determination of total phenolic compounds by Folin-Denis method from Panax ginseng C.A. Meyer and their extraction conditions. It was possible to apply the method for determination of total phenolic compounds from Korean red ginseng. But 3 kinds of amino acids such as tyrosine, cystein and tryptophan, and 3 kinds of vitamins such as ascorbic acid, pyridoxin HCI and thiamine HCI affected strongly the colorization by the method. Effective alcoholic solvent for the extraction was 60% ethanol, appropriate extraction temperature, time and times were 40-80。C, 1-2 hours and 3 times, respectively.

• Food Science and Preservation
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• v.7 no.3
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• pp.331-336
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• 2000

The phenolic compounds of Korean sweet potatoes, Mokpo 18 and Yulmi, were extracted by using 70%-methanol and the extracts(ME) were fractionated and obtained three fractions such as free phenolic acid(FPAF), soluble phenolic acid ester(SPAF) and insoluble bound phenolic acid(BPAF) fractions. The antioxidative activities(AA) was represented as the peroxide values(POVs). The POVs were calculated by measuring the oxidation of linoleic acid and lard emulsions at $60^{\circ}C$. AA of FPAF has shown the most effective. AA of FPAF were more effective than those of ME in both Yulmi and Mokpo 18. AA of the ME of Mokpo 18 were more effective than those of Yulmi, however, those of FPAF in Ulmi were more effective than in Mokpo 18. The POVs of ME and FPAF of the peel part in both sweet potatoes were more effective than those of peeled part. The qualitative and quantitative analysis of the phenolic compounds in both sweet-potatoes were performed by using high performance liquid chromatography(HPLC) and the major phenolic compounds were identified as chlorogenic acid and caffeic acid. The contents of caffeic acid were 0.684mg/g in the peel part and 0.028mg/g in the peeled part of Yulmi and 0.472mg/g in the peel part and 0.046mg/g in the peeled part of Mokpo 18 and those of chlorogenic acid was 0.674mg/g, 0.926mg/g, and 0.012mg/g, respectively. In comparative test of antioxidative activities between a standard chlorogenic acid and caffeic acid, AA of caffeic acid were more effective than those of chlorogenic acid.