• 농업과학연구
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• 제47권1호
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• pp.67-81
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• 2020

The physicochemical parameters of honey are used to determine the botanic origin of honey and to specify the composition criteria for honey in regulations and standards. The parameters of honeydew and blossom honeys from Korean beekeepers were determined to investigate whether they complied with the composition criteria for honey in the food code legislated by Korean authority and to establish the parameters which should be subjected to principal component analysis for improved differentiation of honeys. The fructose and glucose contents of the honeydew honey did not comply with the composition criteria. The ash content of the honey was closely correlated with CIE a^* and CIE L^* The principal component analysis of fructose to glucose ratio, CIE a^*, CIE L^*, ash content, free acidity, and fructose and glucose contents enabled classification of honeydew, chestnut, multifloral, and acacia honeys. Additional advantage of the principal component analysis (PCA) is that the physicochemical parameters, such as fructose to glucose ratio (F/G) and color, can be determined using the analytical instruments for composition criteria and quality control of honey. This study suggested that composition criteria for honeydew honey should be established in the food code in accordance with international standards. The principal component analysis reported in this study resulted in improved classification of the honeys from Korean beekeepers.

• Applied Biological Chemistry
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• 제46권4호
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• pp.280-284
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• 2003

농업용 살균제와 살충제로서의 활용성 진단과 예측평가 자료로 사용하기 위하여 상용화 된 살균제 133품목과 살충제 152품목의 활성 성분들에 대하여 소수성(LogP), 쌍극자능율(DM), HOMO 및 LUMO 에너지, molar refractivity(MR), polarizability(Pol), van der Waals 분자 표면적 및 부피(Vol), 분자량 및 수화 에너지(hydralion energy) 등, 10 가지의 다양한 물리-화학 파라미터들을 계산하였다. 그리고 살균제와 sterol 생합성 저해제 (DMI: demethylation inhibitor) 및 살충제와 acetylcholine esterase 저해제(AChE)이 가지는 특정한 물리-화학 파라미터들의 범위 값을 설정하였다. 그 결과에 기초하여 다양한 화합물들이 작물 보호제로서 살균제와 살충제로의 활용 가능성이 예측될 것으로 판단되었다.

• 농약과학회지
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• 제7권1호
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• pp.58-65
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• 2003

농업용 약물로서의 활용성 진단과 예측을 위한 기초 자료로서 상용화 된 제초제와 같은 분자량을 가지는 의약 각 245 종에 대한 10 가지의 물리 -화학 파라미터들을 계산하고 제초제와 광합성 (PS-II) 저해제 및 acetolactase synthase (ALS) 저해제들의 특정한 물리-화학 파라미터들에 대한 수치 범위를 비교 검토하였다. 제초제들의 특정 물리-화학 파라미터에 대한 85% 의존적 수치 범위는 소수성 상수 (Obs. logP): $-0.90\sim4.50$, 쌍극자 능율 (DM): $1.80\sim12.22$ Debye, van der Waals 분자부피 (Vol.); $558\sim995Cm^3$ 및 표면적 (S.Area): $194\sim356\;{\AA}^2$, molar refractivity (MR): $53\sim104Cm^3/mol$., 분극율 (Pol): $19\sim37\;{\AA}^3$, 분자량 : $202\sim430(amu)$, 및 수화 에너지 (Hy.E): $-10.16\sim114.7$ Kcal/mol 등 이었다. 그리고 작용 기작에 따라 물리-화학파라미터의 범위값을 특징적으로 나타내고 있음을 알았으며 MR 상수와 분극율은 의약과 제초제 (ALS 저해제)를 구분하는 판별 가능한 요소가 될 것으로 예상되었다.

• Reproductive and Developmental Biology
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• 제28권1호
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• pp.45-52
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• 2004

To search a new porcine pheromonal odorants, this research for biostimulation and role of pheromone was augmented by means of "control system technologies" to offer a potentially useful and practical way to improve reproductive efficiency in livestock species. Therefore the 13 physicochemical parameters such as similarity indice (S), hydrophobicity (logP) and van der Waals molecule volume (MV) etc. of 54 steroid analogues, which are analogous of substrate molecules, 5$\alpha$-androst-16-en-3-one (P1) and 5$\alpha$-androst-16-en-3-ol (P2) of lipocalin as receptor of pig pheromones were calculated and discussed. The physicochemical properties of these steroid analogues were mainly followed by steric dissimilar of A and D ring in steroid nucleus. And we found that from correlation with S values and MV constants of molecules, the more MV constants are small, the more S values tend to approach 1. Based on this results, the S-values of 4-androsten-3,17-dione (P1-1) and 5 $\alpha$ -androstan-3-one (P2-1) were 1.0, respectively. The two compounds of them were chosen because they showed the same value each other at a side of hydrophobicity, molar refractivity and molecular volume. It is expected that the new two compounds will be able to substitute for P1 and P2, porcine pheromonal odorants.

• Journal of Ginseng Research
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• 제18권1호
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• pp.60-65
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• 1994

Fresh ginseng of same grade was stored under the 4$\pm$1$^{\circ}C$ and 87~92% RH for 10 weeks. During the storage, an aliquot amount of the ginseng was drawn, freeze dried and chemical constituents and physicochemical parameters were measured. After 10 weeks of storage drying rate and shrinkage of ginseng were 1520% and 9.04%, respectively, mold growth was seen at week 5 and observed for 51.2% of the ginseng week 10. Amylase activity level was elevated at the early stage of storage and decreased to 5% of initial value at week 5. At week 5, the elevated amylase activity was inconcomitant with the appearance of the mold growth. Crude protein contents were increased and decreased, respectively 5 week post storage. No significant changes in crude fat, crude fiber, ash, total sugar, n-butanol extract and ginsenoside were observed. The content of water-extractable substance showed maximum at week 7 to 8. The value of pH was slightly elevated and reducing sugar was increased during the storage. Key words Ginseng storage, physicochemical properties, drying rate, shrinkage, amylase activity.

• 한국대기환경학회지
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• 제20권6호
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• pp.749-758
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• 2004

Nitrous oxide ($N_2$O) has been known as an important trace gas due to the greenhouse gas and the major source of stratospheric oxide of nitrogen (NO). Soil is the major source of $N_2$O in nature. The physicochemical characteristics of soils affect the emission of $N_2$O from soil. These physicochemical parameters are soil moisture, soil temperature, and soil N content. Since these parameters are correlated to the flux of $N_2$O from soil individually and compositely, there still remain many unknowns in the mechanism to produce $N_2$O in soil and the roles of such physicochemical parameters which affect the soil $N_2$O emission. Soil $N_2$O fluxes were measured at different levels in water filled pore space (WFPS), soil temperature and soil N contents from the same amounts of soils which were sampled from agriculturally managed upland field in a depth of ～30 cm at Kunsan. The soil $N_2$O flux measurements were conducted in a laboratory with a closed flux chamber system. The optimum soil moisture and soil temperature were observed at 60% of WFPS and ～13$^{\circ}C$. The soil $N_2$O flux increased as soil N contents increases during the whole experimental hours (up to 48 hours). However, average $N_2$O flux decreased after ～30 hours when organic carbon was mixed with nitrogen in the sample soils. It is suggested that organic carbon could be important for the emission of $N_2$O, and that the ratio of N to C needs to be identified in the process of $N_2$O soil emission.

• 한국식품영양과학회지
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• 제25권4호
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• pp.715-719
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• 1996

Dietary fibers consist mostly of complex carbohydrates such as cellulose, hemicelluloses and pectins, and also included are carbohydrate-based gums or hydrocolloids exampled as alginate, carrageenan, galactomannan xanthan, etc. Due to structural diversity, dietary fibers can be classified by various ways i.e., source, plant function, solubility, charge and topology. Understanding on the plant cell wall structure is of primary importance, since physicochemical properties of dietary fibers are dependent on the existence patterns in the cell wall. Depending on the four distinct observational dimensions, the physical parameters of dietary fibers were discussed in terms of raw sources, bulky & complex plant cell wall materials, individually separated hydrocolloid materials and specifically designed materials. Each existence state possesses the distinct physical parameters governing a variety of physiological properties of dietary fibers.

• Natural Product Sciences
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• 제12권2호
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• pp.79-84
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• 2006

This study presents a detailed pharmacognostical study of the root and leaf of the crude drug Clerodendrum viscosum Vent. (Verbenaceae), an important plant in the Indian system of medicine. The root and leaf samples were studied using light and confocal microscopy, WHO recommended-physicochemical determinations, and authentic phytochemical procedures. The physicochemical, morphological, and histological parameters presented in this paper may be proposed as parameters to establish the authenticity of C. viscosum root and leaf, and may possibly help to differentiate the drug from its other species.

• Natural Product Sciences
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• 제12권2호
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• pp.85-88
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• 2006

This study presents a detailed pharmacognostical study of the underground portion of the crude drug Sphaeranthus indicus Linn. (Asteraceae), an important plant in the Indian system of medicine. The root and stolon were studied using procedures of light, conofocal microscopy, WHO recommended-physicochemical determinations, and authentic phytochemical procedures. The physicochemical, morphological, and histological parameters presented in this paper may be proposed as parameters to identify and establish the authenticity of S. indicus root and stolon.

• 한국지반환경공학회 논문집
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• 제11권11호
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• pp.27-36
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• 2010

본 연구는 정읍시에서 배출되는 하수슬러지, 축산 분뇨, 음식물 쓰레기를 대상으로 Pilot-scale($100m^3$) 초고온 호기성 퇴비화 공정에서의 온도, pH, C/N비, 함수율, 유기물 함량, 그리고 부피 등 물리 화학적 영양 인자를 평가하였다. 각각의 대상 물질은 1차 발효(유기성 폐기물+종균)와 2차 발효(유기성 폐기물+종균+반송 퇴비)로 나누어 수행하였다. 퇴비화가 진행됨에 따라 교반과 송풍만으로 열공급 없이 온도는 1,2차 발효에서 최고온도 $90{\sim}105^{\circ}C$가 되었다. pH, $O_2$, $CO_2$, $NH_3$, 농도 변화는 전형적인 미생물에 의한 유기물 분해 양상을 보여주었으며, 다른 모든 물리 화학적 인자들은 일반 호기성 퇴비화의 성능 이상을 보여주었다. 발효가 완료된 후 퇴비의 중금속 농도는 퇴비 비료 규격 기준 농도에 적합한 것으로 나타났다.