Flemiphyllin,an isoflavone from stems of Flemingia macrophylla

A new isoflavone, designated flemiphyllin, was isolated from a petrol extract of the stems of Flemingia macrophylla. Its structure was established as 5,7,4′-trihydroxy-3′,5′,8-tri(3-methylbut-2-enyl) isoflavone on the basis of physical and chemical evidence.     

大豆籽粒发育过程中异黄酮合成相关酶基因的表达模式与异黄酮积累的相关分析

利用高效液相色谱法和实时定量PCR方法,分别测定了2个异黄酮含量显著差异的大豆品种鲁黑豆2号(LHD2)和南汇早黑豆(NHZ)在子粒发育过程中的异黄酮含量变化以及异黄酮合成相关酶基因的表达模式变化,试图分析异黄酮积累与各基因表达量变化的相关关系。结果表明在大豆子粒发育过程中,异黄酮含量逐渐升高,而不同异黄酮合成相关酶基因的表达趋势不同,CHS7、CHS8、CHR、CHI1A和IFS2的表达趋势与异黄酮积累模式基本一致,而IFS1和CHI1B1的表达趋势与异黄酮积累模式相反。IFR的表达模式在2个大豆品种中存在相反的趋势,在LHD2中与异黄酮组分积累趋势相反,而在NHZ中与异黄酮组分积累趋势相同。结果还表明,同一基因家族中不同基因在子粒发育过程中的表达量也存在差异。查尔酮合酶基因家族中CHS7和CHS8以及查尔酮异构酶基因家族的CHI1A的表达水平相对其他成员较高,异黄酮合酶基因家族中IFS2的表达量显著高于IFS1的表达量,预示这些基因家族在大豆子粒异黄酮积累过程中存在功能分化。此外,各基因表达模式与异黄酮积累的相关分析结果表明,不同基因表达模式与异黄酮积累的相关性在2个品种中也不尽相同。LHD2中CHS7、CHS8和IFS2在子粒发育过程中的表达量变化与不同异黄酮组分呈显著正相关,CHI1B1基因的表达量变化与不同异黄酮组分呈显著负相关。而在NHZ中,IFR在子粒发育过程中的表达量变化与多个异黄酮组分呈显著正相关。这预示了不同大豆品种异黄酮含量差异的潜在遗传基础。各异黄酮合成相关酶基因表达量变化的相关分析表明,在2个品种中,苯丙氨酸水解酶PAL1与4CL,4CL与CHS2以及CHS1与IFS2基因的表达量均呈现显著正相关。表明这些基因可能通过协同作用共同调控异黄酮的合成与积累。这些结果为今后利用基因工程提高大豆异黄酮含量奠定了基础。     

丹贝发酵过程中大豆异黄酮组分与含量的变化

用HPLC方法检测大豆[Glycine max(Linn.)Merr.]发酵食品－丹贝的发酵过程中异黄酮各组分含量变化。在发酵的最初24h内,大部分异黄酮由糖甙转化成甙元,随着发酵时间的延长转化率逐渐降低,发酵终产物中异黄酮主要以大豆甙元和染料木素形式存在,发酵64h的丹贝中总异黄酮摩尔含量比未发酵的大豆高51．25％。     

New isoflavonoids related to kievitone from Phaseolus vulgaris

The new isoflavonoids 5,7,2′,4′-tetrahydroxy-8-(3,3-dimethylallyl)isoflavone (2,3-dehydrokievitone) and 7,2′,4′-trihydroxy-8-(3,3-dimethylallyl)isoflavanone (5-deoxykievitone) have been isolated from fungus-inoculated Phaseolus vulgaris pod tissue and from the inoculation droplets. A third isoflavonoid was tentatively identified as 1″,2″-dehydrocyclokievitone and appears to be a metabolite of the phytoalexin kievitone.     

Ultrastructural observations on the sporogony of Eimeria maxima

Pittilo R. M. and Ball S. J. 1985. Ultrastructural observations on the sporogony of Eimeria maxima. International Journal for Parasilology15: 617–620. Sporogony in Eimeria maxima was found to commence with a contraction of the oocyst cytoplasmic mass which was limited by a single membrane. By 9 h (at 29°C) dense bodies, surrounded by polysaccharide granules, were closely applied to the zygote limiting membrane. By 12 h nuclear division had occurred and by 15 h separate sporoblasts could be discerned. Sporozoite formation occurred from 21 to 30 h.     

Induction of stress metabolite formation in suspension cultures of Vigna angularis

Three isoflavone glucosides were isolated from cell suspension cultures of red bean (Vigna angularis) treated with actinomycin D and identified as     

Evaluation of the Preventive Effect of Isoflavone Extract on Bone Loss in Ovariectomized Rats

To examine a potential role for soybean phytoestrogens in postmenopausal bone loss, twenty-four 12-week-old Sprague-Dawley rats were divided randomly into 4 groups and given controlled diets for 16 weeks. The treatment groups were as followed: sham operated, ovariectomized (OVX) control, OVX + isoflavone extract (6.25 g/kg), and OVX + 17β-estradiol (4 mg/kg). OVX treatments reduced femoral and fourth lumbar vertebral bone density and mineral content (p<0.01), decreased uterine weight (p<0.01), accelerated body weight increases (p<0.05), and increased the activities (p<0.01) of both serum alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP). Supplementation with isoflavone prevented the losses of bone density and mineral content caused by OVX (p<0.01). Although both isoflavone and 17β-estradiol exhibited similar bone-sparing ability on the OVX-induced bone loss, the effect of isoflavone was not the same as that of 17β-estradiol on the serum ALP and TRAP, body weight increase, and uterine weight change. We concluded that dietary supplementation with soybean isoflavone can prevent postmenopausal bone loss via a different mechanism of estrogen in OVX rats.     

Additional flavanoids in Gliricidia sepium

A chromatographic examination of the acetone extractives of the moderately marine bore resistant Panamanian wood Gliricidia sepium has resulted in the isolation and characterization of three new flavanoid constituents: an isoflavone, a dihydroflavonol and a β-hydroxydihydrochalcone. These new flavanoids are not related to the marine bore resistance of the wood.     

Developmental and nutritional regulation of isoflavone secretion from soybean roots

Isoflavones play important roles in plant–microbe interactions in rhizospheres. Soybean roots secrete daidzein and genistein to attract rhizobia. Despite the importance of isoflavones in plant–microbe interactions, little is known about the developmental and nutritional regulation of isoflavone secretion from soybean roots. In this study, soybeans were grown in hydroponic culture, and isoflavone contents in tissues, isoflavone secretion from the roots, and the expression of isoflavone conjugates hydrolyzing beta-glucosidase (ICHG) were investigated. Isoflavone contents did not show strong growth-dependent changes, while secretion of daidzein from the roots dramatically changed, with higher secretion during vegetative stages. Coordinately, the expression of ICHG also peaked at vegetative stages. Nitrogen deficiency resulted in 8- and 15-fold increases in secretion of daidzein and genistein, respectively, with no induction of ICHG. Taken together, these results suggest that large amounts of isoflavones were secreted during vegetative stages via the hydrolysis of (malonyl)glucosides with ICHG.     

Viridiflorin,an isoflavone from Tephrosia viridiflora

A new isoflavone, viridiflorin, has been isolated from Tephrosia viridiflora. Its structure was established as 4′,5,7-trihydroxy-2′,5′-dimethoxy-6-prenylisoflavone based on spectral evidence and chemical transformation.     

Bacterial neuraminidase inhibitory effects of prenylated isoflavones from roots of Flemingia philippinensis

Bacterial neuraminidase (NA) is one of the key enzymes involved in pathogenesis of inflammation during infection. The organic extract of the roots of Flemingia philippinensis showed high bacterial NA inhibitory activity with an IC₅₀ of around 5 μg/mL. Activity-guided separation of the methanol extract yielded nine prenylated isoflavones together with the novel species isoflavone (2) which was given the name flemingsin. Isolated prenylated isoflavones (1–9) were evaluated for NA inhibition and their IC₅₀ values were determined to range between 0.30 and 56.8 μM. The most potent inhibitor 4 (IC₅₀ = 300 nM, K_i = 130 nM) features a catechol motif in the B-ring and a furan in the A-ring. Structure–activity analysis also showed a 4-hydroxyl group within the B-ring was essential for NA inhibitory activity, because isoflavone (9) having protected 4-hydroxyl group was much less potent than its hydroxylated counterpart. All neuraminidase compounds screened were found to be reversible noncompetitive inhibitors. Furthermore, the most active NA inhibitors (1–9) were proven to be present in the native roots in high quantities by HPLC and LC-DAD-ESI/MS.     

干旱胁迫对苗期大豆异黄酮合成的影响

以不同耐旱性的2个大豆品种(高耐旱JP-6、低耐旱JP-16)为研究材料,采用高效液相色谱和实时荧光定量PCR技术,分析不同时间持续干旱胁迫下,大豆叶片和根系中异黄酮的积累变化及关键酶基因的表达情况.结果表明:大豆根部异黄酮含量显著高于叶部,而异黄酮关键酶基因的表达量则在叶片中更高,耐旱品种JP-6根部的异黄酮积累量更大.随着干旱胁迫持续时间的增加,不同耐旱品种的异黄酮合成与积累变化规律存在显著差异:强耐旱品种JP-6的根和叶中,异黄酮积累量均呈现先下降后升高的趋势;而弱耐旱品种JP-16则相反,异黄酮积累量在不同部位中均呈现先上升后降低的趋势;除JP-6叶中C4H、4CL、IFS2等异黄酮合成上游基因外,其他不同品种、不同部位的关键酶基因表达量均随着干旱胁迫持续时间的增加,呈现先下降后上升的趋势.大豆叶片是异黄酮的主要合成部位,大豆根部也存在少量的异黄酮合成.弱耐旱大豆根部的异黄酮合成和最终积累量均较低,强耐旱品种则较高.根部异黄酮积累量高的大豆品种,其耐旱性更强.     

矮秆大豆突变体异黄酮含量变化的研究

以大豆品种东农42及其两个矮秆突变体(HK8和HK11)为原料,采用Luminol-K₃Fe(CN)₆化学发光体系的流动注射化学发光法对茎、叶和种子中的异黄酮进行检测,同时与HPLC检测方法相比较。结果表明:该方法能较简便快速地检测异黄酮含量,相对标准偏差(RSD)为0.69%～2.30%,回收率为95.5%～104.5%。该实验准确地检测出三种大豆材料中异黄酮含量; 异黄酮含量与株高成正比; 种子的异黄酮含量比茎、叶的均高     

Transfer of Soy Isoflavone into the Egg Yolk of Chickens

A diet containing a high concentration of soy isoflavone was administered to laying hens and the contents of the isoflavones transferred to the plasma and egg yolk were measured. A method for quantitatively measuring the concentration of isoflavone in the yolk was first established, before a high concentration of soy isoflavone was administered to the laying hens over an 18-day period. The concentrations of isoflavone in the plasma and egg yolk reached their highest on the 12th day of the feeding period, the values being 3,167 nmol/l and 65.29 μg/100g, respectively. The concentration of cholesterol in the yolk was slightly affected during the early stages of the feeding period. These findings clearly demonstrate that soy isoflavone was transferred into the yolk from the feed and that the cholesterol concentration in the yolk was affected by administering the soy isoflavone-enriched feed.     

A new isoflavone from soya beans

A new isoflavone was isolated from soya beans and shown to be 7,4′-dihydroxy, 6-methoxyisoflavone, for which the name glycitein is proposed.     

葛花不同工艺提取物的异黄酮成分含量比较研究

目的:以不同浓度乙醇和大孔吸附树脂法提取和纯化葛花的提取物,并用HPLC和UV进行异黄酮成分含量比较分析。方法:以不同浓度的乙醇回流提取葛花药材制备提取物,并采用大孔吸附树脂对其进行纯化;然后以HPLC法对提取物中的3种主要黄酮类成分进行定量分析,并以UV法测定其总黄酮含量。结果:葛花不同提取物的黄酮类成分含量差别较大;所建立的HPLC方法可以同时测定葛花提取物中鸢尾苷、6"-O-木糖鸢尾苷和染料木素的含量;UV法与HPLC法联合应用,可对不同葛花提取物中的异黄酮类成分进行评价。结论:不同工艺提取的葛花提取物中异黄酮类成分有较大区别,大孔吸附树脂纯化后可显著提高总黄酮的纯度;HPLC联合UV法可共同用于葛花的质量评价及提取工艺的研究。     

大豆异黄酮合成途径相关基因差异表达分析

大豆异黄酮是一种应用广泛、具有医用和保健功能的活性物质。为揭示异黄酮合成途径相关基因表达差异,本研究采用实时定量PCR技术分析相关基因在不同大豆品种、发育时期及组织部位的表达。结果发现,苯丙氨酸解氨酶基因PAL、肉桂酸羟化酶基因C4H、香豆酸辅酶A连接酶基因4CL在高异黄酮品种中豆27 R2期叶片中的表达量显著高于低异黄酮品种楚秀;查尔酮合成酶基因CHS、异黄酮合成酶基因IFS在中豆27 R8期子粒中的表达量显著高于楚秀;细胞色素还原酶基因CPR在中豆27 R7期叶片与子粒的表达量与楚秀相比显著降低。这些差异表达的基因可能是形成大豆品种异黄酮含量高低的重要原因。     

Effects of Capsaicin and Isoflavone on Blood Pressure and Serum Levels of Insulin-Like Growth Factor-I in Normotensive and Hypertensive Volunteers with Alopecia

Insulin-like growth factor-I (IGF-I) reduces arterial blood pressure. Since administration of capsaicin and isoflavone increases serum levels of IGF-I by sensory neuron stimulation in subjects with alopecia, it is possible that administration of capsaicin and isoflavone reduces arterial blood pressure in patients with hypertension. Systolic and diastolic blood pressure (BP) and serum levels of IGF-I were determined before and at 1, 3, and 5 months after administration of capsaicin and isoflavone in 42 volunteers with alopecia, 29 normotensive and 13 hypertensive volunteers. Neither systolic nor diastolic BP changed in the normotensive volunteers after combined administration of capsaicin and isoflavone. In contrast, systolic and diastolic BP was significantly reduced in hypertensive volunteers after administration of capsaicin and isoflavone. Serum levels of IGF-I significantly increased in both normotensive and hypertensive volunteers after administration of capsaicin and isoflavone. These observations suggest that administration of capsaicin and isoflavone might reduce BP in hypertensive, but not in normotensive subjects, probably by increasing serum levels of IGF-I.     

双歧异黄酮奶粉对化疗荷瘤小鼠减毒增效作用的研究

目的：研究双歧异黄酮奶粉对化疗后荷瘤小鼠免疫功能的影响。方法：以S180荷瘤C57BL／6小鼠为模型,系统地研究双歧异黄酮奶粉对瘤重和细胞功能的影响。结果：双歧异黄酮奶粉对荷瘤鼠化疗所引起的免疫功能低下具有明显的恢复作用,可显著提高化疗荷瘤鼠T细胞转化能力,明显促进化疗荷瘤鼠白介素—2(IL—2)分泌水平。结论;双歧异黄酮奶粉能够拮抗肿瘤抗原和化疗所引起的免疫抑制。     

Multigene synergism increases the isoflavone and proanthocyanidin contents of Medicago truncatula

Isoflavones and proanthocyanidins (PAs), which are flavonoid derivatives, possess many health benefits and play important roles in forage‐based livestock production. However, the foliage of Medicago species accumulates limited levels of both isoflavones and PAs. In this study, biosynthesis of isoflavone and PA in Medicago truncatula was enhanced via synergy between soya bean isoflavone synthase (IFS1); two upstream enzymes, chalcone synthase (CHS) and chalcone isomerase (CHI); and the endogenous flavanone 3‐hydroxylase (F3H). Constitutive expression of GmIFS1 alone resulted in ectopic accumulation of the isoflavone daidzein and large increases in the levels of the isoflavones formononetin, genistein and biochanin A in the leaves. Furthermore, coexpression of GmIFS1 with GmCHS7 and GmCHI1A generally increased the available flux to flavonoid biosynthesis and resulted in elevated isoflavone, flavone and PA contents. In addition, down‐regulation of MtF3H combined with coexpression of GmIFS1, GmCHS7 and GmCHI1A led to the highest isoflavone levels (up to 2 μmol/g fresh weight in total). Taken together, our results demonstrate that multigene synergism is a powerful means to enhance the biosynthesis of particular flavonoids and can be more broadly applied to the metabolic engineering of forage species.