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        검색결과 48

        2.
        2023.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Flexible supercapacitors (FS) are ideal as power backups for upcoming stretchable electronics due to their high power density and good mechanical compliance. However, lacking technology for FS mass manufacturing is still a significant obstacle. The present study describes a novel method for preparing FS based on reduced graphene oxide (RGO) using the N+ plasma technique, in which N+ reduces graphene oxide on the surface of a cotton/polyester substrate. The effect of aloe vera (AV) as a natural reducing & capping agent and carbon nanotubes (CNT) as nanoconductors on the electrochemical performance of the electrodes is studied. FESEM and XPS were employed to investigate the electrodes' structural and chemical composition of electrodes. The galvanostatic charge–discharge curves of electrodes revealed the enhancement of the electrochemical activity of the as-prepared electrode upon additions of AV and CNT. The areal capacitance of the RGO, RGO/AV, and RGO/ AV/CNT supercapacitors at 5 mV/s was 511, 1244.5, and 1879 mF/cm2, respectively. The RGO electrode showed capacitive retention of 80.9% after 2000 cycles enhanced to 89.7% and 92% for RGO/AV and RGO/AV/CNT electrodes, respectively. The equivalent series resistance of the RGO electrode was 126.28 Ω, decreased to 56.62 and 40.06 Ω for RGO/AV and RGO/ AV/CNT electrodes, respectively.
        4,000원
        4.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 기능성 물질인 알로에를 종류별로 첨가함에 따라 유화소시지의 이화학적 특성과 저장성, 그리고 관능성에 미치는 영향을 조사하기 위해 수행되었다. 알로에 베라(AV구)와 알로에 사포나리아(AS구)는 각 3%씩 첨가하였으며, 모든 처리구들은 냉장온도 4±1℃에서 4주간 저장하면서 주 1회 간격으로 실험이 진행되었다. pH는 AV구와 AS구가 대조구보다 유의적(p<0.05)으로 낮았고, 저장기간의 경과함에 따라 대조구 및 모든 처리구는 증가하였다. 보수성에서 AS구는 대조구와 AV구보다 유의적(p<0.05)으로 높은 값을 나타냈으며, 저장기간의 경과함에 따라 대조구 및 모든 처리구는 유의적(p<0.05)으로 감소하였다. 적색도는 AS구가 대조구 및 AV구 보다 낮은 값을 나타내었고, 황색도는 AS구가 대조구, AV구보다 높은 값을 나타내었다. 전단가는 AS구가 대조구보다 낮은 값을 나타냈으며, AV구와는 유의적인 차이가 없었다. 지방 산패도에서 AS구는 유의적 (p<0.05)으로 가장 낮은 값을 나타내었고, 관능 평가의 색은 AV구가 가장 높은 값을 나타냈으며, 선호도는 AV구가 대조구보다 높은 값을 나타냈고 AS구와는 유의적인 차이가 없었다. 이는 알로에 사포나리아의 첨가가 높은 보수성, 알로에 베라 첨가보다 낮은 지방산패도, 유사한 관능성을 나타내 기능성 소시지의 개발에 충분한 경쟁력을 가지고 있으며 향후 알로에 사포나리아를 첨가한 육제품의 일반화 및 대량생산 체계의 확립에 긍정적인 영향을 준다고 판단된다.
        4,200원
        5.
        2017.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aloe-emodin (AE) is the major bioactive component in aloe and known to exhibit anti-inflammatory activities. However, it has not been elucidated whether its anti-inflammatory potency can contribute to the elimination of obesity. The aim of the current study is to investigate the effect of AE on toll-like receptor 4 (TLR4) pathways in the presence of lipopolysaccharide (LPS) in 3T3-L1 adipocytes. 3T3-L1 adipocytes were treated with AE (0-20 μM) for one hour, followed by LPS treatment for 30 min and then, adipokine mRNA expression levels were measured. Next, TLR4-related molecules were measured in LPS-stimulated 3T3-L1 adipocytes. AE significantly decreased the mRNA expression of the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) in a dose-dependent manner. Moreover, AE suppressed TLR4 mRNA expression. Further study showed that AE could suppress the nuclear factor-κB (NF-κB) and phosphorylation of extracellular receptor-activated kinase (pERK). The results of this study suggest that AE directly inhibits TLR4/NF-κB/ERK signaling pathways and decreases the inflammatory response in adipocytes.
        4,000원
        6.
        2014.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aloe is an attractive potential food source because it has functional uses. It has been widely used as a well-being food and drink. The antioxidant activity was estimated by measuring DPPH free radical scavenging activity. We investigated the quality characteristics of cookies prepared by adding various concentrations of aloe powder (0%, 1%, 3%, 5%, all w/w) as a substitute for flour. In this study, the DPPH free radical scavenging activity, moisture content, and hardness of cookies significantly increased with increasing aloe powder, while the pH, spread factor and L and b values slightly decreased. Sensory evaluation scores in terms of texture were shown to be very similar statistically, but color, flavor, taste, and overall acceptability scores were lower than the control. As a result of this study, the quality of cookies with the addition of 1% aloe powder were the most suitable in terms of taste, flavor, texture, and sensory properties.
        4,000원
        7.
        2014.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        온실에서 재배되는 수입 알로에묘목에 알로에베라진딧물, Aloephagus myersi Essig, 이 채집되었다. 이 종의 원산지는 아프리카로 알려져 있고 수입된 식물을 통해 온실에 도입된 것으로 추정된다. 우리나라의 자연환경에 도입과 정착을 방지하기 위한 이들 종의 진단형질, 사진자료, 기주 및 분포정보를 제공하고자 한다.
        3,000원
        8.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 알로에 베라 섭취에 의한 독성 간염이 보고되고 있으나, 아직까지 알로에 베라의 간에 대한 염증 효과가 명확히 밝혀지지 않았다. 본 연구는 알로에 베라 에탄올 추출물이 간세포의 염증 발현에 미치는 영향과 그 기전을 밝히기 위해 수행되었다. 0.001~100 μg/mL의 알로에 베라 추출물을 HepG2세포에 처리하여 MTT assay를 시행한 결과, 모든 농도에서 세포사멸이 유도되지 않았다. 그러나 모든 농도에서 알로에 베라 추출물은 염증성 사이토카인인 IL-8의 분비를 15.7~25.8%까지 유의적으로 증가시켰다(p<0.05). 또 다른 사이토카인인 M-CSF도 알로에 베라 추출물에 의해 36.3~61.5%까지 유의적으로 분비가 증가되었다(p<0.05). 본 연구 결과는 알로에 베라 추출물이 IL-8과 M-CSF와 같은 염증성 사이토카인 분비기전에 의해 간에 염증을 유발할 수 있음을 보여준다. 또한 알로에 추출물에 의해 유발될 수 있는 간염기전을 제시함으로써, 향후 수행될 추가 실험을 위한 기초 자료로 그 가치가 높을 것으로 사료된다.
        4,000원
        9.
        2014.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The glucomannan content of Aloe vera gel was measured by a novel method using a bentonite suspension that floc-culates upon mixing with gels prepared by hand filleting of aloe leaf. An optimum flocculation condition was deter-mined to be Aloe vera gel diluted in the range of 2 to 5-fold and then a bentonite suspension 1% (w/v) mixed withthe gel sample in the ratio of 8:2 (v/v) to provide a mixture volume of 10mL with the length to diameter ratio of5. Under the conditions of these experiments, a rapid settling (<3 min) of more than 90% of the bentonite wasachieved only when the aloe gel sample was properly diluted. The glucomannan concentrations in various dilutedsamples with the highest settling rates were identified in the range of 195.7±21.4mg/L; thus, the results indicate thatthe glucomannan content may be determined from the dilution rate of the aloe gel sample that exhibits the highestsettling rate. This study provides a simple, rapid, and cost-effective assay for the estimation of the glucomannanlevel in raw Aloe vera gel.
        4,000원
        10.
        2013.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two fractions (permeate and retentate) from fiber free Aloe vera gel were prepared using an ultra-filtration (UF) system with a tubular ceramic membrane (MWCO of 50 kDa), and their dilute solution properties were investigated. The intrinsic viscosities of fiber free Aloe vera gel and the retentate and permeate fractions that were prepared by ultra-filtration were 18.48, 37.74, and 2.01 dL/g, respectively. UF aloe retentate as a polysaccharide rich fraction exhibited polyelectrolyte behavior showing a sharp decrease of intrinsic viscosity by the addition of NaCl. However, as its NaCl concentration increasing to 1 M, its intrinsic viscosity slightly increased due to conformational change caused by the high concentration of NaCl. On the one hand, the intrinsic viscosities of the dilute UF-retentate solution were exponentially decreased with increasing temperature, and the temperature dependency of its intrinsic viscosity showed a sharp discontinuity at 30oC instead of a linear Arrhenius behaviour, indicating a variation of flow mechanism or network rearrangement of a molecular chain. The chain stiffness of polysaccharide rich fraction at bellow and above 0.5 M of NaCl addition was 0.048 and 0.515, respectively, showing different stiffenings and significant conformational change. The coil overlap parameter and critical concentration of UF-retentate were 3.0 and 0.08 g/dL, respectively.
        4,000원
        11.
        2013.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        알로에의 최소공정개발 연구의 일환으로 DIS(dewatering & impregnation soaking) 공정에 미치는 온도의 효과를 조사하였다. 삼투탈수는 분자량 4000의 PEG을 삼투제로 하여 이의 40%(w/v) 용액에 두께 0.5 cm의 알로에 잎 슬라이스를 넣고 간헐적으로 교반하면서 2시간 동안 수행하였다. 서로 다른 침지온도(25-55oC)가 DIS의 성능(수분소실 및 고형분 획득)에 미치는 영향을 현미경관찰에 의한 세포조직 구조의 경시변화를 모니터링하면서 조사, 비교되었고, 동역학적으로 분석하였다. 고온(55oC) 처리에서는 저온(25 and 35oC)에서보다 더 높은 수분소실을 보였으나 세포조직의 파괴를 동반하였다. 또, 품질지표값으로서의 glucomannan 함량은 세포조직구조를 잘 유지하였던 침지온도 35oC에서 얻어졌다. 얻어진 시료의 실온건조제품을 재수화시켜 조사하고 동역학적으로 해석한 결과, 재수화 동역학은 Peleg 및 Weibull 모델로 잘 설명할 수 있었다. DIS 제품은 DIS 처리하지 않은 제품에 비해 세포구조 및 재수화성질의 향상을 주어 적정온도하에서 DIS 처리함으로써 최소공정의 알로에 제품을 얻을 수 있음을 확인하였다.
        4,000원
        12.
        2013.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two fractions (permeate and retentate) from fiber-free Aloe vera gel were separated using ultra-filtration (UF) system with tubular ceramic membrane (MWCO of 50 kDa), and their molecular properties were investigated. The retentate of UF Aloe gel was a polysaccharide-rich fraction containing about 2.3-fold higher polysaccharide content than fiber-free gel. The FT-IR and 1H NMR spectra of this fraction showed the characteristic patterns of β-binding polysaccharide and a higher degree of acetylation indicating a higher level of bioactive polysaccharide content. The molecular weight and polydispersity of polysaccharide fraction from GPC (gel permeation chromatography) were determined to be 36.8-43.9 kDa and 1.24, respectively, indicating a kind of undispersed polysaccharide. From the SEM observation, the surface structure of polysaccharide fraction had a gel cluster-like structure with a convoluted rough surface. The molecular conformation by Congo red assay exhibited a property of helix structure confirming the existence of a higher-ordered structure as a biological activity conformation.
        4,000원
        13.
        2013.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The optimization of dewatering and impregnation soaking (DIS) process for a concentrated Aloe vera product was investigated using Taguchi method in combination with desirability function analysis. Polyethylene glycol (PEG) as osmotic agent was adopted, and soaking temperature (T), immersion time (t), PEG concentration (C), PEG molecular weight (MW), and thickness of Aloe vera leaf slice (x) were selected as affecting variables. L16 (45) orthogonal array was designed by Taguchi method with four parameters such as water loss, solid gain, glucomannan, and anthraquinone contents as objective functions. An overall quality index was transformed from individual objective functions, and was optimized finally. The optimal setting for maximum overall desirability was obtained at 55oC (T), 2 hr (t), 40% w/v (C), 0.5 cm (x), and 4,000 Da. (MW). The obtained overall desirability was 0.7842. The order of affecting factors was T>C>x>MW≈x>t and the experimental results under optimum condition were similar to the prediction of an overall desirability of 0.8384. Also, it was found that the optimized DIS condition could be reproduced for a minimally processed Aloe vera product with high quality.
        4,200원
        14.
        2012.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study intented to standardize the method for total polysaccharide, which is a functional marker for aloe vera gel in Korea. We used four lyophilized raw materials and commercial aloe gel products, certified as Health Functional Food by Korea Food and Drug Administration, including powder, solution, jelly, tablet and capsule, to optimize the analytical condition of dialysis and phenol-sulfuric acid reaction in polysaccharide analysis. The optimal conditions for polysaccharide analysis included 1 L water for dialysis and change 3 times for 24hr against 25 mL prepared sample solution. Validation test showed lower than 5% of coefficient of variation(CV) in intra-, interday validation in lyophilized raw materials and 4 types of commercial products. In inter-person and inter-laboratory validation with 4 persons from 4 different laboratories, CV(%) were 5.50 and 6.64 respectively. The linearity of polysaccharide analysis was assessed using 5 serial concentration of lyophilized raw materials(0.1, 0.2, 0.3, 0.4, 0.5%(w/v)). The results showed R2 ≥ 0.995 of high linearity. In the commercial aloe vera gel products, the results of reproductivity showed lower than 7.08% and revealed that the standardized method from this study ensured high precision for polysaccharide analysis.
        4,000원
        15.
        2012.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The extracellular polysaccharide production from suspension culture of Aloe vera L. was analyzed, and the optimization for suspension cultivation was investigated. From specific polysaccharide assay of glucomannan, FT-IR and 1H NMR spectrum, the extracellular polysacchride from suspension culture was found to be similar to β-1,4-glucomannan originated from Aloe vera fresh leaf. The polysaccharide existed in an acetylated form and its molecular weight by gel permeation chromatography was estimated to be 490 kD (Mn = 440 kD; polydispersity = 1.115). From medium optimization by simplex-cemtroid design using MINITAB®, the callus growth on the 2,4-D of 11.82 μM, kinetin of 13.84 μM and α-naphthalene acetic acid of 4.34 μM was turned out to be significantly superior than the growth on the other culture media combinations. Under this optimal culture media, other conditions such as the suspension culture's temperature, pH and the growth terms were determined. These results showed that the callus growth was optimum at 25oC, pH 5.5 and in 2 weeks. The maximum levels of growth and extracellular polysaccharide production of callus by optimal conditions were about 20.4 and 2.5 g/L, respectively, showing the profile of extracellular polysaccharide production was closely related to the callus growth.
        4,000원
        16.
        2012.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A callus formation from Aloe vera L. was inducted, and the tissue cultivation of induced callus was investigated. As a result of using a combined growth factors kinetin and NAA (or 2,4-D) varying from 0.5 to 30 μM and 3% sucrose in MS solid medium, the callus grew better than using either kinetin or auxins alone. Supplementation of 2,4-D in the combined growth factor formulation showed an enhanced callus growth. The maximum callus growth occurred when kinetin 5 μM and 2,4-D 30 μM were added in the MS medium. The optimal culture conditions for the callus growth were 25oC, pH 5.5 and 8-10 weeks of cultivation, yielding callus weight of 11.03 mg/aloe tissue (0.5 cm2). Water or ethanol (60%, v/v) extracts from Aloe callus contained the bioactives contents of fresh Aloe vera gel such as glucomannan, and the level of total phenolics content was much higher than that of Aloe vera whole leaf, suggesting the possibility as an alternative production method of Aloe vera bioactives.
        4,000원
        17.
        2010.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A fiber fraction (Aloe cellulose), the by-product obtained from Aloe vera gel processing was freeze dried and investigated for in vitro glucose/ bile acid retarding effects of powdered sample (100 mesh) comparing with commercial α-cellulose as a reference sample. We also examined the effectiveness of physiological functionality such as the antiobesity and anti-constipation on Sprague-Dawley (SD) rat. The Aloe cellulose powders during in vitro dialysis experiment for 2 hours exhibited the glucose and bile acid retarding index of 20.32-35.2% and 53.13-28.30%, respectively. Especially, freeze dried aloe cellulose showed the 2.5 and 1.2-6 times higher effect on in vitro glucose and bile acid retardation than those of α-cellulose. These relatively good retarding effects on glucose and bile acid diffusion suggest a potential of preventing from diabetes and arteriosclerosis of some extent. Also, the results from animal experiments on SD rats fed a high-fat diet for 4 weeks suggested that Aloe cellulose might be used as a novel dietary fiber showing an effective anti-obesity and anti-constipation effect.
        4,000원
        18.
        2010.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The fibrous material fraction as a by-product from the commercial aloe vera gel processing was obtained and freeze dried. The physicochemical characteristics such as the proximate composition, crystalline/surface structures and several physical functionalities including the water holding capacity (WHC), swelling capacity (SW), oil holding capacity (OHC), emulsion/foam properties and viscosity properties of this powdered sample (100 mesh) were investigated and analyzed by comparison with commercial α-cellulose as a reference sample. The total dietary fiber content of powdered sample was very high as much as 87.5%, and the insoluble dietary and soluble dietary fiber content ratios were 77.6 and 22.4%, respectively. The FT-IR spectrum of powdered sample showed a typical polysaccharide property and exhibited a x-ray diffraction pattern for cellulose III and IV like structure. SW (8.24±0.15 mL/g), WHC(6.40±0.19 g water/g solid) and OHC(10.32±0.29 g oil/g solid) of freeze dried aloe cellulose were about 3.3, 1.4 and 2 times higher than those of commercial α-cellulose, respectively. Aloe cellulose (~2%, w/v) alone had no foam capacity while improved the foam stability of protein solution (1% albumin+0.5% CaCl2) by factor of 300%. Emulsion capacity of 2%(w/v) aloe cellulose was about 70% level of 0.5%(w/v) xanthan gum, but its emulsion stability was about 1.2 times higher than that of xanthan gum. Also, aloe cellulose containing CMC (carboxyl methyl cellulose) of 0.3%(w/v) showed a very good dispersity. Aloe cellulose dispersion of above 1%(w/v) exhibited higher pseudoplasticity and concentration dependence than those of α-cellulose dispersion, indicating the viscosity properties for new potential usage such as an excellent thickening agent.
        4,000원
        19.
        2009.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In vitro physiological functions such as jack bean (Canavalia ensiformis) urease inhibitory activity and retarding effect of glucose/bile acid of Aloe vera gel concentrated by the optimized DIS (Dewatering Impregnation & Soaking) process conditions were examined. Urease inhibitory activity of DIS aloes ranged from 84.6 to 94.4%, which was similar to or higher than 86.3% of fresh aloe. Also, urease inhibitory activity of DIS aloes was maintained at initial levels after heat treatment (90oC, 10 min.) and drying treatment (freeze or hot air drying). Urease inhibition pattern from Lineweaver-Burk plot indicated general non-competitive inhibition, and inhibition constants (KIE and KIES) of DIS aloes were 41-149 and 87-163 μL/mL, respectively. DIS(glucose) and DIS (polyethylene glycol) exhibited the highest retarding effect of glucose and bile acid. Their retarding effects were about 1.6 and 1.8 folds higher than that of fresh aloe after 0.5 and 1 hr of the dialysis, respectively. Conclusively, the above in vitro physiological functions of Aloe vera gel concentrated by DIS process suggested that aloe products treated with DIS would have the potential benefits for protection against Helicobacter pylori and reduction of blood glucose and cholesterol levels.
        4,200원
        20.
        2009.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aloe gel의 동결건조에 농축도가 서로 다른 액상 시료를 사용하였을 때 건조분말의 기능성 변화를 비교분석하였다. Aloe의 많은 기능성 중에서 유효 다당류의 농도, 기능성 작용기에 대한 FT-IR 특성, Jack bean urease 저해 효과, FAC(fat adsorption capacity)를 대상으로 하였다. 농축도가 높은 경우에 유효 다당류의 농도, urease 저해 효과, FAC 모두 상대적으로 크게 나타났다. FT-IR의 분석에서는 농축도가 높은 경우에 glucomannan의 acetyl 기에 대한 spectrum 영역인 1600-1550 cm-1와 1450-1400 cm-1에서 흡광도가 크게 관찰되었다. 결과적으로 Aloe gel의 동결건조 시 전처리과정인 농축 공정에서는 농축도가 높을수록 유효 다당류의 양과 acetyl기 함량의 수준이 크며, 간접적으로 urease 저해 효과에 따른 Helicobacter pylori의 억제 및 FAC의 증가 효과를 보였다.
        4,000원
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