• Food Science and Preservation
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• v.31 no.3
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• pp.374-384
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• 2024

Soybean paste is a staple food used to make doenjang (DE), cheonggukjang (CGJ), and miso (MI). In this study, solid-phase microextraction followed by gas chromatography-mass spectrometry was used to identify volatile components in DE, CGJ, and MI, and principal component analysis (PCA) was performed to determine their correlation between soybean pastes. Esters and hydrocarbons accounted for more than 55% of the total volatile components. PCA showed that esters were highly correlated with DE; pyrazines were correlated with CGJ; and alcohols were highly correlated with MI. Because DE, CGJ, and MI are made of the same material, their overall volatile content tended to be similar. However, the main volatile components and fragrances were different. These findings will be used as basic research data to promote quality improvement of soybean-based fermented foods in Korea and Japan.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.225-236
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• 2019

BACKGROUND: Hydroponics is one of the methods for evaluating plant production using the inorganic nutrient solutions, which is applied under the artificial light conditions of plant factory system. However, the application of the conventional inorganic nutrients for hydroponics caused several environmental problems: waste from culture mediums and high nitrate concentration in plants. Organic nutrients are generally irrigated as a supplementary fertilizer for plant growth promotion under field or greenhouse conditions. Hydroponic culture using organic nutrients derived from the agricultural by-products such as dumped stems, leaves or immature fruits is rarely considered in plant factory system. Effect of organic or conventional inorganic nutrient solutions on the growth and nutrient absorption pattern of green and red leaf lettuces was investigated in this experiment under fluorescent lamps (FL) and mixture Light-Emitting Diodes (LEDs). METHODS AND RESULTS: Single solution of tomatoes (TJ) and kales (K) deriving from agricultural by-products including leaves or stems and its mixed solution (mixture ration 1:1) with conventional inorganic Yamazaki (Y) were supplied for hydroponics under the plant factory system. The Yamazaki solution was considered as a control. 'Jeockchima' and 'Cheongchima' lettuce seedlings (Lactuca sativa L.) were used as plant materials. The seedlings which developed 2~3 true leaves were grown under the light qualities of FL and mixed LED lights of blue plus red plus white of 1:2:1 mixture in energy ratio for 35 days. Light intensity of the light sources was controlled at 180 μmol/㎡/s on the culture bed. The single and mixture nutrient solutions of organic and/or inorganic components which controlled at 1.5 dS/m EC and 5.8 pH were regularly irrigated by the deep flow technique (DFT) system on the culture gutters. Number of unfolded leaves of the seedlings grown under the single or mixed nutrient solutions were significantly increased compared to the conventional Y treatment. Leaf extension of 'Jeockchima' under the mixture LED radiation condition was not affected by Y and YK or YTJ mixture treatments. SPAD value in 'Jeockchima' leaves exposed by FL under the YK mixture medium was approximately 45 % higher than under conventional Y treatment. Otherwise, the maximum SPAD value in the leaves of 'Cheongchima' seedlings was shown in YK treatment under the mixture LED lights. NO₃-N contents in Y treatment treated with inorganic nutrient at the end of the experiment were up to 75% declined rather than increased over 60 % in the K and TJ organic treatment. CONCLUSION: Growth of the seedlings was affected by the mixture treatments of the organic and inorganic solutions, although similar or lower dry weight was recorded than in the inorganic treatment Y under the plant factory system. Treatment Y containing the highest NO₃-N content among the considered nutrients influenced growth increment of the seedlings comparing to the other nutrients. However effect of the higher NO₃-N content in the seedling growth was different according to the light qualities considered in the experiment as shown in leaf expansion, pigmentation or dry weight promotion under the single or mixed nutrients.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.72-86
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• 2014

This study was conducted to investigate the effects of mulching of easily-decomposable organic materials including rice powder and corn starch on rice paddy fields. The treatments were including seven mulching materials each consisted of rice powder [Rice], starch with black color [Starch-B] and transparent [Starch-T] and stone powder [Stone], and conventional vinyl [Conventional], no-mulching without herbicide [Control-O] and no-mulching with herbicide [Control-C]. Rice growth and yield were different among the treatments; the highest yields were observed for [Rice] ($6.51ton\;ha^{-1}$) and [Conventional] ($6.47ton\;ha^{-1}$) followed by [Starch-T] ($6.25ton\;ha^{-1}$) and [Stone] ($6.20ton\;ha^{-1}$) which is comparable to the [Control-C] ($6.15ton\;ha^{-1}$). However, [Starch-B] showed lower rice yield ($4.93ton\;ha^{-1}$) than the [Conventional] or [Control-C]. Mean soil temperature ranged form 23.6 to $24.1^{\circ}C$ with the highest temperature for [Rice] treatment, and cumulative soil temperature was also significantly higher in the [Rice] treatment. Among the soil parameters, electrical conductivity, organic matter content, and phosphorus concentration were also different among the treatments. The amount of earthworm casting was higher for [Rice] treatment ($17.7kg\;m^{-2}$) compared to the others ($5.5{\sim}9.8kg\;m^{-2}$). It was suggested that mulching of rice fields with organic materials containing rice powder is better than others in respected to rice yield and earthworm activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.227-233
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• 1986

The compositions and seasonal variations of free sugars and non-volatile organic acids of brown algae, such as Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides were investigated by gas chromatography. Four kinds of free sugars, such as xylose, glucose, galactose and floridoside were identified. The most abundant one was floridoside marking 118.7 mg/100 g, 90.9 mg/100 g and 70.0 mg/100 g in Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinguishable seasonal variations in the contents of free sugars in all the samples. In the case of organic acids, nine kinds were identified in Ecklenia cava and major ones were succinic, citric, malic, fumaric, oxalic and lactic acid, of which succinic acid was the most abundant one marking $30.6\%$ of total organic acids. In Sargassum ringgoldianum and Myagropsis myagroides, eight kinds were identified, which major ones were succinic, citric and malic acid in both samples, and they marked $68.4\%$ and $61.1\%$ of total organic acids in Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinct changes in the content of total organic acids according to seasons in all the samples examined. The contents of total organic acics in Ecklonia cava was a little more than Sargassnm ringgoldianum and Myagropsis myagroides.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.82-86
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• 2009

The objective of this study was to evaluate the effect of various solvents on extraction of bioactive phenolics and to analyze the antioxidant capacity and contents of individual catechins in various grades of green teas organically grown in Boseong, Korea. The organic green teas, based on their harvest seasons, were categorized into five grades such as Woo-Jeon, Se-Jak, Jung-Jak, Dae-Jak, and coarse tea. Solvents used to extract phenolics from these teas included water at $23^{\circ}C$ and $70^{\circ}C$ as well as 80% (v/v) aqueous methanol and ethanol. In general, aqueous organic solvents of methanol and ethanol led to higher extraction yields of phenolics than water at $23^{\circ}C$ and $70^{\circ}C$. Total phenolics and antioxidant capacity of the teas extracted with the aqueous organic solvents were approximately 1.5 to 3.2 and 1.8 to 3.8 times higher than those with water at $23^{\circ}C$ and $70^{\circ}C$, respectively. Coarse tea, the lowest grade of green tea, showed approximately 30-60% lower total phenolics and antioxidant capacity compared with the higher grade ones. Reversed-phase HPLC analysis was performed quantitatively to identify individual catechins, gallic acid, and caffeine in teas extracted with 80% (v/v) aqueous methanol. Based on their dry weights, the organic green teas contained about 1.7 to 2.9% of caffeine. Content (mg/g dry weight) of tea catechins decreased in the following order: Woo-Jeon (155.4) > Se-Jak (147.7) > Jung-Jak (143.2) > coarse tea (135.1) > Dae-Jak (130.5). (-)-Epigallocatechin gallate was the most abundant among the catechins analyzed. The highest grade of green tea, Woo-Jeon, had the highest amount of (-)-epigallocatechin gallate at 77.4 mg/g dry weight. Overall, the higher grade of organic green teas tended to have the higher level of antioxidant capacity and catechins.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.176-184
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• 2019

The rice variety Chucheongbyeo is mostly cultivated for organic farming in the central region of Korea. This variety is more delicate than the recently developed varieties in rice yield, quality, and pest resistance, and is therefore, not suitable for organic farming. This study was conducted to select suitable varieties for organic rice farming in the central plain area of Korea. We tested 15 different varieties in the organic paddy field of Cheongju city from 2011 to 2013. As the experimental field had good fertility because it had been organically managed for many years, culm length and number of panicles developed better than the varietal characteristics. Daebo, Chinnong and Hyeonpum had slightly lower ripened grain ratio than Chucheongbyeo. The milled rice yield of Samkwang, Sukwang, Haiami, Cheonghaejinmi and Daebo increased by 9-18% compared to that of Chucheongbyeo. The protein content was under 7% for Cheongnam, Sukwang, Daebo, Samkwang, Hyeonpum, Chinnong, Chilbo, Hopyung, Hwangkeumnuri, Suryeojinmi and Jinsumi and under 6% for Sukwang and Samkwang. The whiteness was over 40 in Sukwang, Daebo, Samkwang and Jinsumi. The palatability grade and head rice ratio were good in Daebo, Sukwang, Samkwang and Jinsumi. Therefore, this study recommended Samkwang, Daebo, and Jinsumi as the optimal varieties for organic rice farming in the central plain area of Korea. These varieties could replace Chucheongbyeo, which is inferior to the recently developed varieties in terms of disease and pest resistance and yielding performance.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.42-47
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• 2005

The possibility of using Moringa oleifera as a ruminant protein supplement was investigated by comparison between nutritive and anti-nutritive value of its different morphological parts with that of conventionally used Leucaena leucocephala leaf meal (LL). Parameters determined were chemical composition, rumen degradable protein (RDP), acid detergent insoluble protein (ADIP), pepsin soluble protein (PESP), non-protein nitrogen (NPN) total soluble protein (TSP) and protein potentially digested in the intestine (PDI). Total phenols (TP) and total extractable tannins (TET) were also evaluated as anti-nutritive factors. In vitro gas production characteristics were measured and organic matter digestibility (OMD) was estimated basing on 24 h-gas production. Crude protein content ranged from 265-308 g/kg DM in M. oleifera leaves (MOL) and seed cake (MOC) respectively. Leucaena leucocephala and Moringa oleifera soft twigs and leaves (MOLSTL) had CP content of 236 and 195 g/kg DM while Moringa oleifera soft twigs alone (MOST) and Moringa oleifera bucks (MOB) had 160, 114 and 69.3 g/kg DM respectively. RDP was highest in (MOC) (181 g/kg DM) followed by (MOL) (177 g/kg DM) and was lowest in MOB (40 g/kg DM). The proportion of the protein that was not available to the animal (ADIP) was (p<0.05) higher in MOL and MOC (72 and 73 g/kg DM) respectively and lowest in LL (29 g/kg DM). The PDI was high in LL (74 g/kg DM) followed by MOC (55 g/kg DM) then MOL (16 g/kg DM). PESP was highest (p<0.05) in MOC followed by MOL then LL (273, 200 and 163 g/kg DM respectively). MOC exhibited highest NPN content (116 g/kg DM) and was lowest in MOB (18 g/kg DM) (p<0.05). Highly (p<0.05) TSP was observed in MOC and MOL (308 and 265 g/kg DM respectively) followed by LL (236 g/kg DM). MOL had negligible TET (20 g/kg DM) when compared with about 70 g/kg DM in LL. Highly (p<0.05) b and a+b values were observed for MOLSTL (602 and 691 g/kg DM respectively) followed by MOL (490 and 538 g/kg DM). Highest c value was observed in MOSTL followed by MOC and MOL (0.064, 0.056 and 0.053 rate/hour) respectively. OMD was highest (p<0.05) for MOSTL followed by MOC and then MOL (579, 579 and 562 g/kg DM respectively). LL exhibited lower (p<0.05) OMD (467 g/kg DM). It was concluded from this study that the high crude protein content in MOL and MOLST could be well utilized by ruminant animals and increase animal performance however, high proportion of unavailable protein to the lower gut of animals and high rumen degradable protein due to negligible tannin content render it a relatively poor protein supplement for ruminants. MOC can be a best alternative protein supplement to leaves and leaves and soft twigs for ruminants.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.111-120
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• 1993

We investigated in the existential forms of heavy metals and their distribution in plant and soil surrounding ruined mine in Daduk area. The content of heavy metals in soils was more plentiful in A soil than that in another soil, excepting only Mn. The content of Mn in soils was greater in B soil than those in another soils. The content of each heavy metals, according to existential form, had different patterns on the comparision of each elements ; organic-form on Cd and As, Carbonate-form Cu, Pb and Mn and Residual-form on Fe and Zn. The popularity ration of M. senensis and J. decipiens were about 65% and 72%, respectively, and which means that these plants had resistances to heavy metals. The contents of heavy metals absorbed in root was higher than those of stem except Mn, In M. sinensis, the contents of Zn in root was similar to that of stem. To study the heavy metal contents in water, the highest content of heavy metal, mainly Fe, Mn and Zn, were calculated in extracting water.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1649-1657
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• 2006

In order to find an alternative source of inoculum to caecal content for studying the fermentation activity of rabbit hindgut, caecal content and faeces of 25 hybrid Hyla rabbits were used as inocula for an in vitro gas production trial. About 1 g of three substrates (dehydrated alfalfa meal, dehydrated beet pulp, barley) was weighed, in quadruplicate per inoculum, in 120 ml bottles; 75 ml of anaerobic medium and 4 ml of reducing solution were added and bottles were placed at $39^{\circ}C$. Caecal content and faeces were diluted respectively 1:2 (CI) and 1:8 (FI) with anaerobic medium and were introduced in the respective bottles (10 ml). Gas production was recorded 20 times at 2-24 h intervals throughout fermentation (96 h). The fermentation characteristics (i.e. degraded organic matter, OMd; potential gas production, A; fermentation rate, Rmax; time at which it is reached, Tmax; pH, volatile fatty acid, VFA) were studied by inoculum and feedstuffs. The feedstuffs, according to their chemical composition, showed very different fermentation characteristics. In particular, OMd, A and Rmax allowed feedstuff classification as follows: barley>beet pulp>alfalfa. The inocula differ (p<0.05) in Tmax, were higher for CI (15.53 vs. 11.96 h) and in VFA production. In particular, CI produced higher levels of acetate (38.9 vs. 33.4 mM/g OM incubated, p<0.01) and isobutyrate (0.72 vs. 0.42, p<0.01) but less propionate (7.1 vs. 10.3, p<0.01) and butyrate (11.3 vs. 14.0, p<0.01). However, the trend of gas production, similar for the inocula according to the fermented substrate, and the good regression equation to estimate some caecal fermentation parameters from faeces suggest that, after standardisation, the faeces could be used as an alternative inoculum for gas tests in rabbit.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.986-993
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• 2001

In balance experiments with rats either 25 or 50% of the casein protein in the control diet was replaced with one of the following eight sun-dried tropical biomass products: water spinach plants (WS) (Ipomoea aquatica Forsk), leucaena leaves (LL) (Leuceana leucocephala), duckweed plants (DW) (Lemma minor L.), groundnut foliage (OF) (Arachis hypogaea L.), trichantera leaves (Tric) (Trichantera gigantea), indicago leaves (Ind) (Indigofera hirsuta), mungbean foliage (Mb) (Phaseolus aureus), and cassava leaves (CL) (Manihot esculenta Crantz). The experiment included 102 rats with six individuals per treatment group. In three of the 16 biomass treatment groups, feed intake and weight gain of the rats were unacceptably low, and therefore they were excluded from the statistical evaluation, The crude protein (CP) content of the biomass products varied between 20.9% (Tric) and 33.2% (DW), whereas the content of NDF varied between 18.5% (Ind) and 32.2% (DW) of dry matter (DM). The total content of essential amino acids (g/16 g N) was comparable with that of alfalfa meal, except for GF and Tric, which were inferior. Between plant species, differences in dietary digestibility of organic matter (dOM) and CP (dCP) were observed (p<0.001). Also, the replacement level negatively influenced dOM and dCP (p<0.001). The lowest values for dOM (p<0.001) were observed for diets including biomass products with the highest content of NDF (OF, Tric, Mb, LL). Digestibility of CP was negatively affected by level of protein replacement. Significant (p<0.001) differences were found in N-retention and biological value among diets with different biomass products. The most favourable overall results were obtained for DW, WS and CL. The main factors affecting the nutritive value of the diets tested were their NDF content, dCP and AA profile of the biomass. Also antinutritive component(s) may have influenced the process of digestion and metabolism of some of the biomass products.