胁迫对菜用大豆种子抗坏血酸-谷胱甘肽循环的影响

采用蛭石栽培,在100 mmol/L NaCl 胁迫下,对耐盐性不同的两个菜用大豆［Glycine max (L.)Merr.］品种种子的过氧化氢（H2O2）含量及抗坏血酸-谷胱甘肽（AsA-GSH）循环进行了研究。结果显示,NaCl胁迫显著增加了菜用大豆种子的H2O2含量,但耐盐品种 绿领特早的增幅低于盐敏感品种理想高产95-1。NaCl胁迫期间,绿领特早种子中抗坏血酸过氧化物酶（APX）、脱氢抗坏血酸还原酶（DHAR）、谷胱甘肽还原酶（GR）活性,AsA、GSH含量以及AsA/DHA值和GSH/GSSG值的增幅高于同期的理想高产95-1,或降幅低于同期的理想高产95-1; 脱氢抗坏血酸（DHA）、氧化型谷胱甘肽（GSSG）含量的增幅低于同期的理想高产95-1。表明 绿领特早种子在胁迫期间能够保持较高的AsA-GSH循环效率,可有效地抑制H2O2的积累,这可能是其耐盐性较强的重要原因之一。     

H_2S对低温胁迫下甜樱桃柱头和子房AsA-GSH循环的响应

为了探究H_2S对甜樱桃花器官低温伤害的缓解机理,以甜樱桃品种早大果为试材,分析了不同浓度H_2S供体NaHS对低温胁迫下甜樱桃柱头和子房AsA-GSH循环系统的影响。结果表明,喷施0.02、0.05、0.1 mmol·L~(-1)的NaHS均可降低低温胁迫下甜樱桃柱头和子房超氧阴离子(O_2~-)、过氧化氢(H_2O_2)、丙二醛(MDA)含量,显著提高还原型抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量(P0.05),降低氧化型抗坏血酸(DHA)和氧化型谷胱甘肽(GSSG)含量,使AsA/DHA和GSH/GSSG比值显著升高(P0.05),以0.05 mmol·L~(-1)NaHS效果最显著;0.02、0.05、0.1 mmol·L~(-1)的NaHS均显著提高低温胁迫下柱头和子房AsA-GSH循环中抗坏血酸过氧化物酶(APX)、脱氢抗坏血酸还原酶(DHAR)、单脱氢抗坏血酸还原酶(MDAR)、谷胱甘肽还原酶(GR)、谷胱甘肽过氧化物酶(GPX)和谷胱甘肽-S-转移酶(GST)的活性(P0.05),以0.05 mmol·L~(-1)NaHS提高上述酶活性的幅度最大。NaHS的浓度大于0.2 mmol·L~(-1)不再提高低温胁迫下AsA-GSH循环效率;低温胁迫下添加NaHS的同时添加H_2S清除剂HT可解除H_2S的效果。综上所述,喷施适量外源H_2S可有效降低低温胁迫下O_2~-、H_2O,和MDA积累,提高AsA-GSH循环效率,减轻低温对甜樱桃柱头和子房的氧化伤害。本研究结果为明确H_2S缓解甜樱桃花器官低温伤害作用机制以及生产上花期低温伤害预防提供了理论依据。     

嘧霉胺替代多菌灵在柑橘贮藏过程中的降解及防效研究

多菌灵残留超标已成为影响我国农产品出口的一大制约因素,积极开展多菌灵安全用药研究,寻找多菌灵替代用药方案尤为必要。本研究针对柑橘罐头原料加工果分别开展了以多菌灵、嘧霉胺浸果后的农药残留动态和保鲜防效研究。研究结果显示,柑橘浸药处理后30 d内的保鲜效果,嘧霉胺1 000倍液处理略好于多菌灵600倍液处理;嘧霉胺处理后快速降解,5d后其残留降解到1个较低水平,之后进入缓慢降解过程,且各处理嘧霉胺在果肉中含量均低于0.01 mg/kg;多菌灵处理在柑橘浸药后14 d达到峰值,60 d后果肉中多菌灵含量仍有0.116 mg/kg。如以多菌灵浸药保鲜柑橘用以加工出口,则存在较大的超标风险,而嘧霉胺可以作为多菌灵的替代农药在柑橘贮藏期安全使用。     

棉花幼苗AsA-GSH循环对低温胁迫的响应机制研究

为探究棉花幼苗营养器官抗坏血酸-谷胱甘肽(AsA-GSH)循环系统对低温胁迫的响应机制,以新陆早57号为试验材料,研究4℃低温胁迫不同时间(0、1和2 d)对根、茎和叶中抗氧化物质含量和酶活性的影响。结果表明,与对照(0 d)相比,随着低温胁迫时间延长,棉花幼苗根中还原型抗坏血酸(AsA)含量及单脱氢抗坏血酸还原酶(MDHAR)和谷胱甘肽还原酶(GR)活性呈上升趋势,氧化型抗坏血酸(DHA)含量先减少后增加,氧化型谷胱甘肽(GSSG)含量和脱氢抗坏血酸还原酶(DHAR)活性先升高后降低,谷胱甘肽氧化还原状态(GSH/GSSG比率)和抗坏血酸过氧化物酶(APX)活性总体呈下降趋势,抗坏血酸氧化还原状态(AsA/DHA比率)、还原型谷胱甘肽(GSH)含量和谷胱甘肽过氧化物酶(GPX)活性无显著性差异;茎和叶中AsA和GSH含量、AsA/DHA比率及APX、MDHAR和GR活性总体呈上升趋势,且茎中DHAR活性升高,DHA和GSSG含量先减少后增加,GSH/GSSG比率和GPX活性无显著性差异,而叶中DHA含量和GSH/GSSG比率先不变后增加,DHAR活性先升高后降低,GSSG含量和GPX活性无显著性差异。综合分析显示,棉花幼苗通过调节根、茎和叶中抗氧化物质含量和酶活性来清除活性氧,从而适应低温胁迫,减轻低温伤害。此外,低温对根中AsA-GSH循环影响最大。本研究结果为揭示低温胁迫对棉花幼苗AsA-GSH循环代谢机制提供了理论依据。     

壳聚糖和抗坏血酸复合处理提高台湾青枣采后保鲜效果

为了延长台湾青枣(Ziziphus mauritiana Lam.)的采后保鲜时间,基于抗坏血酸(ascorbic acid,As A)可提高果实抗氧化能力,壳聚糖涂膜处理能防止果实失水和微生物侵染,该文探讨抗坏血酸、壳聚糖涂膜及抗坏血酸和壳聚糖复合处理对台湾青枣(Ziziphus mauritiana Lam.)采后保鲜效果的影响.果实采收后当天,分别用30.0mmol/L抗坏血酸浸泡处理、8g/L壳聚糖涂膜以及30.0mmol/L抗坏血酸浸泡后并用8g/L壳聚糖涂膜复合处理,以双蒸水浸泡处理为对照,处理结束后,置于(25±1)℃和90%~95%相对湿度下贮藏,定期测定果实相关生理参数,扫描电镜观察果皮果实组织结构.结果表明,与对照相比,抗坏血酸或壳聚糖单独处理虽然对台湾青枣保鲜有一定效果,但复合处理后保鲜效果更好.表现为显著减少果实失水率和相对电导率(P<0.05),抑制果皮叶绿素降解及果实果胶酶和多聚半乳糖醛酸酶活性增加,降低原果胶分解成可溶性果胶的速率(P<0.05),使果实硬度和细胞完整性得以维持;延缓果实超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)活性下降,降低膜脂氧化速率,果实过氧化氢和膜脂过氧化产物丙二醛含量显著下降(P<0.05);维持果实较高的可溶性固形物(total soluble solids,SS)、可溶性总糖(total soluble sugar,TSS)、可滴定酸(titratable acidity,TA)、谷胱甘肽(glutathione,GSH)及抗坏血酸含量.研究结果说明,抗坏血酸和壳聚糖复合处理可提高台湾青枣贮藏过程中的抗氧化能力,降低氧化伤害;降低果实失水率,减缓果皮叶绿素降解速率,延缓细胞降解和软化速率,维持果实细胞完整性,降低果实的腐烂率,从而达到延长采后果实保鲜的效果.     

NaCl胁迫对菜用大豆种子抗坏血酸-谷胱甘肽循环的影响

采用蛭石栽培,在100 mmol/L NaCl胁迫下,对耐盐性不同的两个菜用大豆[Glycine max(L.)Merr.]品种种子的过氧化氢(H2O2)含量及抗坏血酸-谷胱甘肽(AsA-GSH)循环进行了研究。结果显示,NaCl胁迫显著增加了菜用大豆种子的H2O2含量,但耐盐品种"绿领特早"的增幅低于盐敏感品种"理想高产95-1"。NaCl胁迫期间,"绿领特早"种子中抗坏血酸过氧化物酶(APX)、脱氢抗坏血酸还原酶(DHAR)、谷胱甘肽还原酶(GR)活性,AsA、GSH含量以及AsA/DHA值和GSH/GSSG值的增幅高于同期的"理想高产95-1",或降幅低于同期的"理想高产95-1";脱氢抗坏血酸(DHA)、氧化型谷胱甘肽(GSSG)含量的增幅低于同期的"理想高产95-1"。表明"绿领特早"种子在胁迫期间能够保持较高的AsA-GSH循环效率,可有效地抑制H2O2的积累,这可能是其耐盐性较强的重要原因之一。     

杀菌剂在荔枝贮藏过程中的残留动态及安全管控研究

以荔枝上常使用的几种主要杀菌剂(多菌灵、抑霉唑、咪鲜胺)为试验对象,研究其在荔枝采后低温贮藏中的残留动态变化规律及其对荔枝的保鲜效果。结果表明,3种杀菌剂在荔枝果实中的残留物主要存在于果皮中,贮藏期间果皮中的杀菌剂会向果肉渗透转移;果皮和果肉中残留量受药液处理浓度的影响,高浓度药液处理的荔枝果皮和果肉中3种杀菌剂残留量均明显高于低浓度处理的荔枝中的残留量,质量安全风险也增加。试验研究为3种杀菌剂在荔枝防腐保鲜上的安全使用提供了科学依据,并提出了安全合理使用的管控措施。     

水分胁迫对玉米根系AsA-GSH H202含量的影响

以“鲁玉14”、“掖单13”2个不同抗旱性玉米品种为材料，研究不同浓度聚乙二醇－6000（PEG－6000）处理下根系抗坏血酸－谷胱甘肽（AsA-GSH)循环中关键酶和抗氧化剂的变化及其对过氧化氢（H2O2）含量的影响结果表明，谷胱甘肽还原酶（GR）、抗坏血酸过氧化物酶（APX）活性及谷胱甘肽（GSH）含量变化为当聚乙二醇溶液浓度低于100g/kg时，随水分胁迫的增强而上升，当聚乙二醇溶液浓度高于150g/kg时，随水分胁迫的增强而下降。抗坏血酸（AsA)含量随水分胁迫的增加而持续下降，H2O2含量随水分胁迫的加剧而增加。聚乙二醇溶液浓度为150－250g/kg处理下H2O2含量的增加与抗氧化酶活性、抗氧化剂含量的下降呈显著正相关。2品种比较，抗旱性强的品种具有较强的抗氧化能力。     

外源NO对Ca(NO_3)_2胁迫下番茄叶片活性氧损伤的缓解效应

为探讨外源一氧化氮(NO)对次生盐渍胁迫下植物抗氧化系统的调节作用,以番茄品种‘秦丰保冠’为试材,在营养液栽培条件下研究叶面喷施外源NO供体硝普钠(SNP)对80mmol·L~(-1)Ca(NO_3)_2胁迫下番茄幼苗生长、叶片光合、活性氧物质、抗氧化酶活性和抗坏血酸-谷胱甘肽(AsA-GSH)循环的影响。结果表明,Ca(NO_3)_2胁迫下喷施SNP处理的番茄幼苗叶片超氧阴离子(O_2~(·-))的产生速率以及过氧化氢(H_2O_2)、丙二醛(MDA)、脱氢抗坏血酸(DHA)、氧化型谷胱甘肽(GSSG)的含量和电解质渗漏率显著降低,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)、脱氢抗坏血酸还原酶(DHAR)和单脱氢抗坏血酸还原酶(MDHAR)的活性显著升高或得以维持,同时叶片抗坏血酸(AsA)、谷胱甘肽(GSH)含量及其还原力(AsA/DHA、GSH/GSSG值)显著升高,叶片活性氧损伤得到有效缓解,叶绿素降解和光合速率的下降得到有效抑制,进而促进了植株的生长发育,提高了番茄幼苗的耐盐能力。     

高压电场处理对贮藏番茄活性氧代谢的调节

为探讨高压电场调控采后果实成熟衰老的作用机理,研究了交变电场和稳恒电场处理对采后番茄活性氧代谢的影响。试验结果表明：交变电场处理可诱导贮藏前期番茄超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性,延缓贮藏后期SOD活性上升和CAT活性下降;稳恒电场处理对酶活性的诱导不显著。两种电场处理均延缓了过氧化物酶（POD）活性高峰出现的时间。稳恒电场处理果实整个贮藏过程中保持了高水平的抗坏血酸（AsA）以及还原型谷胱甘肽（GSH）含量。整个贮藏期间高压电场处理均显著抑制了番茄过氧化氢含量以及超氧阴离子的产生。     

柠檬酸存在下施硅对土壤磷吸附和解吸特性影响

以棕壤为研究对象,采用室内培养的方法,通过加硅酸钙处理、硅酸钙+1 mmol/L柠檬酸处理和硅酸钙+2 mmol/L柠檬酸处理,研究了柠檬酸存在下施硅对棕壤中磷素吸附和解吸特性的影响,并用Langmuir方程、Freundlieh方程与Temkin方程对其进行拟合分析,其中磷吸附解吸试验采用恒温批处理平衡法.结果表明,Langmuir与Temkin模型对处理后棕壤磷的吸附拟合效果最好.硅酸钙+1 mmol/L柠檬酸处理的棕壤对磷的吸附量最大,为500mg/kg;硅酸钙+2 mmol/L柠檬酸处理的棕壤对磷的解吸量及解吸率最大,最大解吸率可达45.2％.因此,硅酸钙+1 mmol/L柠檬酸处理的棕壤对磷肥的储存能力最强,硅酸钙+2 mmol/L柠檬酸处理的棕壤对磷活化能力最强,即供磷能力最强.     

Impact of postharvest disease control methods and cold storage on volatiles, color development and fruit quality in ripe 'kensington pride' mangoes

Postharvest diseases of mango fruit (Mangifera indica L.) cause economic losses during storage and can be controlled by chemical, physical, or biological methods. This study investigated the effects of different physical and/or chemical disease control methods on production of volatiles, color development and other quality parameters in ripe 'Kensington Pride' mango fruit. Hard mature green mango fruit were harvested from an orchard located at Carnavon, Western Australia. The fruit were heat-conditioned (8 h at 40 +/- 0.5 degrees C and 83.5 +/- 0.5% RH), dipped in hot water (52 degrees C/10 min), dipped in prochloraz (Sportak 0.55 mL x L(-1)/5 min), dipped in hot prochloraz (Sportak 0.55 mL x L(-1) at 52 degrees C/5 min), dipped in carbendazim (Spin Flo 2 mL x L(-1)/5 min), and dipped in hot carbendazim (Spin Flo 2 mL x L(-1) at 52 degrees C/5 min). Nontreated fruit served as control. Following the treatments, the fruit were air-dried and kept in cold storage (13 +/- 0.5 degrees C) for three weeks before being ripened at 21 +/- 1 degrees C. The ripe pulp of the fruit that was treated with hot prochloraz or carbendazim at ambient and high temperatures showed enhanced concentrations of volatiles, while heat conditioning and hot water dipping did not significantly affect the volatile development. Ripening time, and color development were measured daily while disease incidence and severity, weight loss, firmness, and concentrations of soluble solids, titratable acidity, ascorbic acid, total carotenoids, and volatiles were determined at the eating soft ripe stage. Hot water dipping or fungicide treatments (at ambient or at a high temperature) reduced postharvest diseases incidence and severity. Fruit quality (soluble solids concentration, titratable acidity, ascorbic acid and total caretonoids) was not substantially affected by any of the treatments.     

Antioxidant action of glutathione and the ascorbic acid/glutathione pair in a model white wine

Glutathione was assessed individually, and in combination with ascorbic acid, for its ability to act as an antioxidant with respect to color development in an oxidizing model white wine system. Glutathione was utilized at concentrations normally found in wine (30 mg/L), as well as at concentrations 20-fold higher (860 mg/L), the latter to afford ascorbic acid (500 mg/L) to glutathione ratios of 1:1. The model wine systems were stored at 45 °C without sulfur dioxide and at saturated oxygen levels, thereby in conditions highly conducive to oxidation. Under these conditions the results demonstrated the higher concentration of glutathione could initially provide protection against oxidative coloration, but eventually induced color formation. In the period during which glutathione offered a protective effect, the production of xanthylium cation pigment precursors and o-quinone-derived phenolic compounds was limited. When glutathione induced coloration, polymeric pigments were formed, but these were different from those found in model wine solutions without glutathione. In the presence of ascorbic acid, high concentrations of glutathione were able to delay the decay in ascorbic acid and inhibit the reaction of ascorbic acid degradation products with the wine flavanol compound (+)-catechin. However, on depletion, the glutathione again induced the production of a range of different polymeric pigments. These results highlight new mechanisms through which glutathione can offer both protection and spoilage during the oxidative coloration of a model wine.     

Determination of phenolic compounds and ascorbic acid in different fractions of tomato by capillary electrophoresis with electrochemical detection

Tomato (Lycopersicon esculentum Mill.), one of the most important crops worldwide, contains different classes of substances with antioxidant properties such as carotenoids, vitamin C, and phenolics. A method based on capillary electrophoresis with electrochemical detection has been developed to analyze ascorbic acid and phenolics in the peel, pulp, and seeds of tomatoes. Operating in a wall-jet configuration, a 300 microm diameter carbon disk electrode was used as the working electrode, which exhibits a good response at +0.90 V (vs saturated calomel electrode) for the analytes. Under optimum conditions, the analytes were baseline separated within 20 min in a 50 mmol/L borate buffer (pH 8.7). Notably, excellent linearity was obtained over 3 orders of magnitude with detection limits (S/N=3) ranging from 1x10(-8) to 2x10(-7) g/mL for all analytes. This proposed method has been successfully applied to monitor the content of ascorbic acid and phenolics in real samples, and the assay results were satisfactory.     

黑麦草分泌有机酸的生物特性对铅污染修复的影响

为了揭示根系分泌有机酸对植物修复效果的影响,该文采用液培试验研究根系分泌有机酸对黑麦草生理特性及重金属pb2+吸收转移的影响.结果表明,黑麦草根系分泌有机酸为草酸、酒石酸、苹果酸、冰乙酸和柠檬酸.0.1～1 mmol/L的内二酸和2～3 mmol/L冰乙酸有利于黑麦草地上和根系干质量的增加.0.1 mmol/L的洒石酸、0.5～l mmol/L的丙二酸、2～3 mmol/L的冰乙酸促进耐性指数的增加.1～3 mmol/L的丙二酸,酒石酸对地上部分Pb2+质量浓度起促进作用,1～3mmol/L的冰乙酸有利于黑麦草 生物量的增加,同时也有利于根系重金属pb2+质量浓度的增加.该研究可为重金属污染的植物修复技术提供参考.     

Formation of furan from carbohydrates and ascorbic acid following exposure to ionizing radiation and thermal processing

This study was conducted to investigate the formation of furan from sugars, ascorbic acid, and organic acids as affected by ionizing radiation and thermal treatments. Results showed that both thermal treatments and irradiation induced formation of furan from ascorbic acid, fructose, sucrose, or glucose. Little furan was produced from malic acid or citric acid. The pH and concentration of sugars and ascorbic acid solutions had profound influences on furan formation due to either irradiation or thermal treatment. The rate of irradiation-induced furan formation increased with decreasing pH from 8 to 3. Approximately 1600 times less furan was formed at pH 8 as apposed to pH 3. At the same pHs, the amounts of furan formed from irradiation of ascorbic acid, fructose, and sucrose were always higher than from glucose. As pH decreased from 7 to 3, an increase in thermally induced furan was observed for sucrose and ascorbic acid solutions, but for glucose solution, less furan was formed at pH 3 than at pH 7. The levels of sugars commonly found in fruits and fruit juices, upon irradiation, would be high enough to potentially produce low parts per billion (ppb) levels of furan. The concentration of ascorbic acid at which a maximum of furan was produced upon irradiation was about 0.5 mg/mL, a level commonly found in some foods. Five furan derivatives were tentatively identified in thermally treated ascorbic acid solution, while one furan derivative was tentatively found in both irradiated and thermally treated samples.     

Effects of low-molecular-mass organic acids on P nutrition and some plant properties of Hordeum vulgare

One of the strategies of the plants growing in phosphorus (P)-deficient environments is to exudate low-molecular-weight organic acids (LMWOA). Thus, we aimed to investigate the effect of LMWOA on phosphorus uptake of barley from either fertilizer or inherited soil phosphorus. The experiment was set up in full factorial arrangement in completely randomised design with two phosphorus (0 and 50 mg P kg^?1), five organic acids, LMWOA (malic acid, oxalic acid, citric acid, acetic acid, ascorbic acid), and four organic acid rates (0, 10, 20, and 30 mmol kg^?1). The effects of LMWOA on yield in descending order were: oxalic acid > ascorbic acid > malic acid > acetic acid > citric acid. The maximum P concentration in grain was obtained at 30 mmol kg^?1 LMWOA treatments. As a result, it was found that oxalic acid was the most effective LMWOA in increasing nutrient uptake induced grain yield with and without phosphorous fertilizer application.     

Comparative study on pressure and temperature stability of 5-methyltetrahydrofolic acid in model systems and in food products

A comparative study on the pressure and temperature stability of 5-methyltetrahydrofolic acid (5-CH(3)-H(4)folate) was performed in model/buffer systems and food products (i.e., orange juice, kiwi puree, carrot juice, and asparagus). Effects of pH and ascorbic acid (0.5 mg/g) on 5-CH(3)-H(4)folate stability in buffer systems were studied on a kinetic basis at different temperatures (from 65 to 160 degrees C) and different pressure/temperature combinations (from 100 to 700 MPa/from 20 to 65 degrees C). These studies showed that (i) the degradation of 5-CH(3)-H(4)folate in all model systems could be described by first-order reaction kinetics, (ii) the thermostability of 5-CH(3)-H(4)folate was enhanced by increasing pH up to 7, (iii) 5-CH(3)-H(4)folate was relatively pressure stable at temperatures lower than 40 degrees C, and (iv) ascorbic acid enhanced both the thermo- and barostabilities of 5-CH(3)-H(4)folate. In food products, temperature and pressure stabilities of 5-CH(3)-H(4)folate were studied at different temperatures (70-120 degrees C) and different pressure/temperature combinations (from 50 to 200 MPa/25 degrees C and 500 MPa/60 degrees C). 5-CH(3)-H(4)folate in orange juice and kiwi puree was relatively temperature (up to 120 degrees C) and pressure (up to 500 MPa/60 degrees C) stable in contrast to carrot juice and asparagus. Addition of ascorbic acid (0.5 mg/g) in carrot juice resulted in a remarkable protective effect on pressure (500 MPa/60 degrees C/40 min) and temperature degradation (120 degrees C/40 min) of 5-CH(3)-H(4)folate.     

单一及复合有机酸对土壤中镉形态的影响研究

为寻找可行的强化重金属污染土壤植物修复的方法,研究了柠檬酸与复合有机酸(苹果酸+柠檬酸)对土壤中重金属Cd各形态的影响。结果表明,对于不同污染程度的CdⅠ~CdⅣ土壤,单一与复合添加有机酸均能有效活化土壤中重金属Cd;当复合添加2.5 mmol kg-1苹果酸+7.5 mmol kg-1柠檬酸时土壤中最具活性的可交换态Cd百分含量增长率显著高于单一添加10 mmol kg-1柠檬酸时的增长率。     

Organic acids from leaves,fruits, and rinds of Garcinia cowa

Organic acids in fresh leaves, fruits, and dried rinds of Garcinia cowa (G. cowa) were determined by high-performance liquid chromatography. Fresh leaves, fruits, and dried rinds were extracted with water at 120 degrees C for 20-30 min under 15 lbs/in(2) pressure. Also, dried rinds were extracted with solvents (acetone and methanol) using a Soxhlet extractor at 60 degrees C for 8 h each. The samples were injected to HPLC under gradient elution with 0.01 M phosphoric acid and methanol with a flow rate of 0.7 mL/min using UV detection at 210 nm. The major organic acid was found to be (-)-hydroxycitric acid present in leaves, fruits, and rinds to the extent of 1.7, 2.3, and 12.7%, respectively. (-)-Hydroxycitric acid lactone, and oxalic and citric acids are present in leaves, fruits, and rinds in minor quantities. This is the first report on the composition of organic acids from G. cowa.