Carotenoid Pigment Changes in Ripening Momordica charantia Fruits

The carotenoid composition of Momordica charantia fruit (pericarp)at four levels of maturity was extensively investigated. Thenumber of carotenoids isolated increased from five in the immaturefruit to six at the mature-green and 14 at the partly-ripe andripe stages. Cryptoxanthin, which could not be isolated at theimmature and mature stages, accumulated rapidly at the onsetof ripening to become the principal pigment of the ripe fruit.Moderate increases were seen in ß-carotene, zeaxanthinand lycopene concentrations as ripening progressed. The reversetrend was observed with lutein and -carotene which were themajor pigments of the immature fruit. Prior to the colour break,only the hydroxy derivatives of -carotene (zeinoxanthin andlutein) could be detected; the ß-hydroxy compounds(cryptoxanthin and zeaxanthin) appeared and predominated thereafter.The hydroxy carotenoids of the ripe fruit were almost entirelyesterified in contrast to those of the unripe fruit which weremainly unesterified. Traces of flavochrome, 5, 6-monoepoxy-ß-carotene,mutatochrome, -carotene, -carotene, -carotene and rubixanthinwere detected in the partly-ripe and ripe fruits but not inthe immature and mature-green samples. Phytofluene was observedin trace levels at all stages.     

苦瓜籽蛋白的分离纯化及免疫原性分析

经过NaCl溶液匀浆抽提、硫酸铵分级分离、SP-Sepharose Fast Flow层析、Sephacryl S-100层析、Macro-Cap-SP层析,从苦瓜籽中同时分离纯化出大量的α-苦瓜素和苦瓜抗HIV蛋白30.经SDS-PAGE鉴定,二者均为单一条带,表观分子量为28 kDa.用两种蛋白分别免疫Balb/c...     

Study of Specific Protein on Sex Differentiation of Momordica charantia

In Momordica charantia L. the soluble protein profile of flower bud at hermaphroditic stage and three early developmental stages (the 7th, 10th and 13th day after initial budding) of male and female flowers were analysed with capillary electrophoresis. Some specific proteins related to sex differentiation were detected. The 11 kD protein, which appeared at the 7th day of budding and existed through the three developmental stages of the female flowers with little change of content, might be an "essential protein" for the expression of female flower differentiation program. Similarly, the 30 kD protein might be an "essential protein" for the expression of the male flower differentiation.     

苦瓜的营养价值、化学成分以及药理作用研究进展

本文总结了半个多世纪来国内外学者对苦瓜的研究,为苦瓜进一步开发提供了借鉴。     

Isolation and Characterization of Two Momordins,Ribosome-Inactivating Proteins from the Seeds of Bitter Gourd (Momordica charantia)

Cathepsins L and L-like (58 kDa) proteinase from mackerel were purified to electrophoretical homogeneity by Concanavalin A-Sepharose and Econo-Pac S chromatographies. The molecular weights of cathepsins L and L-like proteinase were 30,000 and 58,000, and the optimal pH for the hydrolysis of Z-Phe-Arg-MCA (benzyloxycarbonyl-L-phenylalanyl-L-arginine-7-[4-methyl] coumarylamide) were 5.0 and 5.5, respectively. The stability of both purified proteinases at various pHs was low, when the pH was above 7.0. According to the substrate specificity analysis, these proteinases hydrolyzed Z-Phe-Arg-MCA and Z-Arg-Arg-MCA, but did not hydrolyze Z-Arg-MCA and L-Arg-MCA. The activities of these two proteinases were effectively activated by cysteine and dithiothreitol. Their thiol-dependent proteolytic activity against Z-Phe-Arg-MCA was strongly inhibited by E-64 (trans-epoxysuccinyl-L-leucylamido[4-guanidino]butane), antipain, chymostatin, iodoacetic acid, and leupeptin, but not inhibited by pepstatin or phenylmethane sulfonyl floride. The inactivation rate constants (K_D) of cathepsins L and L-like proteinases at 50°C were 5.1 × 10^?5 and 6.9 × 10^?4 s^?1, respectively. K⁺, Na⁺, Mg⁺, and Sr⁺ did not affect them, while Zn²⁺, Cd²⁺, Co²⁺, Ni²⁺, Cu²⁺, Hg²⁺, Fe²⁺, and Fe³⁺ inhibited the activity of the purified cathepsins L and L-like proteinase.     

苦瓜提取物的抑菌活性研究

本文研究了苦瓜(MC)不同活性成分的抑菌活性.结果表明:苦瓜提取物对细菌的抑菌作用明显,但对霉菌、酵母菌的抑制效果不明显.苦瓜粗皂甙和苦瓜粗多糖的抑菌效果比纯品的好.苦瓜乙醇浸提物、苦瓜粗多糖、苦瓜多糖、苦瓜粗皂甙、苦瓜皂甙、苦瓜粗蛋白对藤黄八叠球菌的最低抑菌浓度(MIC)分别为50、100、5、100、2、20 mg/mL.苦瓜多糖、苦瓜皂甙和苦瓜蛋白是苦瓜抑菌活性功能成分.     

Trinorcucurbitane and cucurbitane triterpenoids from the roots of Momordica charantia

Five cucurbitacins, kuguacins A-E (1-5), together with three known analogues, 3beta,7beta,25-trihydroxycucurbita-5,(23E)-diene-19-al (6), 3beta,25-dihydroxy-5beta,19-epoxycucurbita-6,(23E)-diene (7), and momordicine I (8), were isolated from roots of Momordica charantia. Structures of 1-5 were elucidated by NMR and MS spectroscopic analysis. Among them, compounds 3-5 possess an unprecedented 25,26,27-trinorcucurbitane backbone. Compounds 3 and 5 showed moderate anti-HIV-1 activity with EC(50) values of 8.45 and 25.62 microg/ml, and exerted minimal cytotoxicity against C8166 cells (IC(50)>200 microg/ml), with a selectivity index more than 23.68 and 7.81, respectively.     

Purification and Some Properties of Chitinase from Momordica charantia

Chitinase was purified from Momordica charantia L. by affinity chromatography. The purified enzyme showed single band on sodium dodecyl sulfate polyacrylamicle gel electrophoresis and the molecular weight was estimated as 35 kD. The enzyme was stable at temperatures up to 50℃ or less than 10 % loss of activity in 1 h. Its optimum temperature was about 45 ℃. Its suitable pH had a rather wide range from pH 4.4 to pH 6.8 and the optimum pH was about 6.2. The activity of the enzyme was similar in root and stem. In the lower leaves,the activity was higher than that of the upper.     

Hormonal regulation of sex expression in Momordica charantia

Sex expression in a monoecious cucurbit, Momordica charantia L. (long–fruited variety 'Karela') can be regulated by application of gibberellin A₃ (GA₃), indole-3-acetic acid (IAA) and 3-hydroxymethyl oxindole (HMO), an oxidation product of IAA, all of which promote female flowering. Both IAA and HMO accelerated ethylene evolution in the seedlings of this plant. While a low concentration of Ethrel promotes flowering, the effect was reversed with increased concentrations. Surprisingly, GA₃ was the most effective growth regulator in increasing, femaleness. In untreated plants, levels of endogenous GA-like substance increased progressively up to the age of 60 days, at which the ratio of male to female flowers was minimum.     

免疫亲和层析法纯化苦瓜几丁酶

用扁豆几丁酶免疫家兔,获得抗扁豆几丁酶的抗体,将此抗体与Ｓｅｐｈａｒｏｓｅ ４Ｂ偶联,制备免疫亲和吸附剂,用以纯化苦瓜几丁酶．苦瓜叶片的粗提液经过免疫亲和吸附柱后,可获得电泳纯的几丁酶,其分子量为３５ ｋＤ,与用几丁质凝胶为亲和吸附剂的纯化结果一致．表明利用植物几丁酶在结构上的保守性,用免疫亲和法可纯化不同植物的同类几丁酶．与几丁质凝胶亲和柱相比,免疫亲和法纯化植物几丁酶具有快速、亲和柱可重复使用等的优点．利用免疫亲和层析获得的纯化样品,研究了苦瓜几丁酶对真菌的抑制试验,研究结果表明,苦瓜几丁酶能分解棉花枯萎病菌的菌丝体细胞壁制备物,并对其孢子芽管的伸长有一定抑制作用．     

Glycosidic inhibitors of melanogenesis from leaves of Momordica charantia

Eight glycosidic compounds, 1-8, including two new compounds, (4ξ)-α-terpineol 8-O-[α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside] (5) and myrtenol 10-O-[β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside] (7), were isolated from the BuOH-soluble fraction of a MeOH extract of Momordica charantia leaves. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses and comparison with literature. Upon evaluation of compounds 1-8 on the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), these compounds were found to exhibit inhibitory activities with 7.1-27.0% and 23.6-46.4% reduction of melanin content at 30 μM and 100 μM, respectively, with no or almost no toxicity to the cells (80.0-103.5% of cell viability at 100 μM). Western blot analysis showed that compound 7 reduced the protein levels of MITF, tyrosinase, TRP-1, and TRP-2 mostly in a concentration-dependent manner, suggesting that this compound inhibits melanogenesis on the α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase, TRP-1, and TRP-2.     

比色法测定苦瓜中的总皂甙

本试验通过对高氯酸和硫酸体系进行比较,选择香草醛-冰醋酸-高氯酸体系作为测定苦瓜皂甙的合适显色条件,并对体系中各个因素逐一考察,确定比色法测定苦瓜皂甙的条件为：0．2mL冰醋酸,0．8mL高氯酸,5％香草醛．冰醋酸溶液,70℃条件下反应20min。试验以苦瓜皂甙建立了苦瓜皂甙测定回归曲线,线性和稳定性可靠,平均加标回收率100．78％,变异系数为1．910％。     

Pharmacodynamic interaction of Momordica charantia with rosiglitazone in rats

The present study was undertaken to determine the interaction of rosiglitazone, a PPAR-γ agonist with methanolic extract of Momordica charantia L (MC), an herbal drug used widely as an antidiabetic agent. The pharmacodynamic interaction was evaluated in oral glucose tolerance test, streptozotocin (STZ) induced diabetes in adult rats and STZ induced diabetes in neonatal rats. Rosiglitazone was given orally at two different doses of 2 mg/kg and 5 mg/kg and MC was administered at a dose of 500 mg/kg, p.o. The serum glucose level estimation and histopathological studies of pancreas, liver and kidney were carried out. Both rosiglitazone and MC showed hypoglycaemic effect in oral glucose tolerance test. The hypoglycaemic effect observed with combination of rosiglitazone and MC was significantly more compared to either of the drugs given alone. MC also augmented the hypoglycaemic effect of rosiglitazone in both STZ induced diabetes in adult animals and STZ induced diabetes in neonatal rats. Histopathological studies revealed that administration of rosiglitazone with MC increased the volume of islet cell in pancreas and prevented the hepatic damage when compared to control. It was concluded that MC augments hypoglycaemic effect of rosiglitazone. This could be important in reducing the dose of rosiglitazone to achieve enhanced therapeutic effect with minimal adverse effects.     

苦瓜中苦瓜甾苷的提取工艺研究

本研究通过单因素实验和正交实验,采用HPTLC检测方法,以苦瓜甾苷浸提量为考察指标,对影响苦瓜甾苷提取效果的各因素进行了研究。结果表明各因素对苦瓜甾苷提取效果的影响程度从高到低依次为:乙醇浓度>固液比>浸提时间>浸提温度。确定了苦瓜甾苷的最佳提取工艺参数为乙醇浓度80%,浸提温度55℃,浸提时间5h,固液比1:10。     

大孔吸附树脂对苦瓜皂甙的吸附研究

试验通过静态吸附对几种树脂进行筛选,结果表明D-101对苦瓜皂甙有较大的吸附率和解吸率,适合用来提取纯化苦瓜皂甙.进一步对D-101进行动态吸附研究,结果表明,浓度为95%的乙醇,3个柱体积可以洗脱几乎所有的苦瓜皂甙.苦瓜皂甙粗提物的上样浓度为2.8～5.6 ms/mL之间.     

Cucurbitane-type triterpenoids from the aerial parts of Momordica charantia L.

Six new cucurbitane-type triterpenoids (1–6), together with two known analogues (7 and 8) were isolated from the aerial parts of Momordica charantia L. The structures of new compounds were identified as cucurbita-6,24-dien-3β,23-diol-19,5β-olide (1), (19R)-5β,19-epoxy-19-methoxycucurbita-6,24-dien-3β,23-diol (2), (19S)-5β,19-epoxy-19-methoxycucurbita-6,24-dien-3β,23-diol (3), (19R)-5β,19-epoxy-19-isopropoxycucurbita-6,24-dien-3β,23-diol (4), 3β,23-dihydroxy-5-methoxycucurbita-6,24-dien-19-al (5) and (19R)-7β,19-epoxy-19-methoxycucurbita-5,24-dien-3β,23-diol (6), by extensive MS, 1D and 2D NMR spectroscopic technologies. This is the first report of the isolation of tetracyclic triterpenoids possessing a 7β,19-epoxy system, viz., 6, from M. charantia L.     

苦瓜愈伤组织再生植株

1 植物名称苦瓜(Momordica charantia). 　　2 材料类别无菌萌发的种子苗.蓝山大白苦瓜、泰国青绿油身苦瓜种子购自四川省农业科学院种子市场;翠绿1号大顶苦瓜种子由广东省农业科学院蔬菜研究所赠送.……     

苦瓜多糖的提取、分离纯化及组成性质

正交实验确定提取工艺后,用热水提取法得到苦瓜多糖(MCP).对MCP进行DEAE-32离子交换层析分离,得到3个多糖组分MCP1、MCP2和MCP3. 进一步采用Sephacryl S-400凝胶层析进行分离,经凝胶层析和高效液相色谱检测表明,MCP1、MCP2为均一性多糖组分.通过高效液相凝胶色谱法测定了两者的相对分子质量分别为1.16×106和7.45×105.用PMP衍生化法测定其单糖,结果表明: MCP1系由Man、Rham、GlcUA、GalUA、Glu、Gal、Xyl、Ara等单糖组成的杂多糖,摩尔比为1.03:2.93:1.00:14.95:2.16:30.70:2.85:4.50.MCP2系由Rham、GalUA、Gal、Xyl、Ara等单糖组成的杂多糖,对应的摩尔比为1.63:21.88:4.66:1.00:1.29.紫外光谱表明该多糖不含蛋白质和核酸.     

New ribosome-inactivating proteins from seeds and fruits of the bitter gourd Momordica charantia

A new ribosome-inactivating protein (RIP) (δ-momorcharin) and a candidate RIP (ε-momorcharin) were isolated, respectively, from the seeds and fruits of the bitter gourd Momordica charantia, by affinity chromatography on Affi-gel blue gel and ion exchange chromatography on Mono S with a fast protein liquid chromatography (FPLC) system. Both δ- and ε-momorcharins were adsorbed on Affi-gel blue gel and were eluted from the cation exchange Mono S column earlier than α- and β-momorcharins, the two previously reported RIPs, δ- and ε-momorcharins possessed a molecular weight of 30 and 24 kDa respectively and inhibited cell-free translation in rabbit reticulocyte lysate with an IC₅₀ of 0.15 and 170 nM. The sequence of the first seven N-terminal amino acids in δ-momorcharin was DVNFGLA, which was different from the N-terminal sequences DVSFRLS and DVNFDLS for α- and β-momorcharins respectively.