竹叶黄酮的生理与药理活性

介绍了竹子的药用价值和竹叶中的黄酮类化合物的药用历史。研究表明,竹叶黄酮有抗脂质过氧化、扩张冠脉血管和对抗心肌梗塞等作用。并就竹叶黄酮对天然抗氧化剂在食品添加剂中,如肉类、水产品和果汁饮料的应用前景进行了阐述。     

竹叶提取物在腌制食品中的应用研究

竹叶提取物具有抗氧化、清除自由基、抗菌、抗炎等功效。探究不同黄酮含量的竹叶提取物对腌肉抗氧化作用和抑制有害物质亚硝胺的效果,发现0. 2%的高黄酮含量竹叶提取物有较好的抗氧化和抑制亚硝胺的作用,0. 2%的低黄酮含量竹叶提取物也有一定的功效,说明竹叶提取物可作为一种天然抗氧化剂用于腌制食品中。     

HPLC法同时检测刚竹属竹叶中4种黄酮碳苷的含量

建立了HPLC同时检测竹叶中4种黄酮碳苷(异荭草苷、荭草苷、牡荆苷和异牡荆苷)的方法,并测定了这4种常见的黄酮碳苷在24种刚竹属竹叶的含量,以及早园竹4个季度中黄酮碳苷的含量。采用Inertsil ODS-3色谱柱(250 mm×4.6 mm,5μm),以乙腈/0.5%磷酸水溶液(体积比15∶85)为流动相进行等度洗脱,流速为1.0 mL/min,柱温为30℃,检测波长340 nm。实验结果表明:4种黄酮碳苷的质量浓度在1～300 mg/L范围内与峰面积呈良好的线性关系,相关系数均在99%以上,加标回收率(n=3)分别为97.14%、100.53%、93.60%和95.66%,RSD值分别为1.11%、1.45%、1.96%和1.43%;24种刚竹属竹叶中黄酮碳苷含量差异显著,4种黄酮碳苷质量分数的总和在286.14～3 838.79 mg/kg之间,毛金竹最高,为3 838.79 mg/kg;早园竹中4种黄酮碳苷的含量随时间变化差异明显,质量分数的总和在1 371.15～4 367.01 mg/kg之间,其中1月份采摘时总质量分数最高,为4 367.01 mg/kg。HPLC法准确度高,适用于竹叶黄酮碳苷的测定。     

低共熔溶剂-球磨法提取竹叶黄酮碳苷工艺优化

以低共熔溶剂为提取溶剂，用球磨法从毛竹叶中提取黄酮碳苷类化合物，采用高效液相色谱-飞行时间质谱(LC-Q-TOF-MS)测定竹叶中4种黄酮碳苷(异荭草苷、荭草苷、异牡荆苷和牡荆苷)的含量，通过单因素试验和正交试验，对低共熔溶剂的含水量、提取时间、液料比等因素进行考察。结果表明，从竹叶中提取黄酮碳苷的最佳工艺为：低共熔溶剂(氯化胆碱和乙二醇构成)含水量50%、提取时间150 s、液料比6∶1(mL∶g)。在该条件下，从竹叶中提取4种黄酮碳苷的总提取得率为1.55 mg/g,其中，异荭草苷0.99 mg/g、荭草苷0.23 mg/g、牡荆苷0.04 mg/g、异牡荆苷0.29 mg/g。该方法提取得率比浸渍提取法提高了7.6%,且节约了时间和有机溶剂。利用该优化工艺，结合LC-Q-TOF-MS检测，成功应用于以毛竹叶为原料制成竹茶样品的黄酮碳苷提取与测定。     

长节箬竹叶总黄酮提取工艺

以长节箬竹叶为材料,乙醇为萃取剂,研究了竹叶黄酮提取工艺,并用UV-2450型分光光度计对竹叶原料总黄酮含量进行测定.通过对单因素条件的选择和正交试验,确定了提取长节箬竹叶黄酮的最佳工艺条件为乙醇浓度85%,提取水浴温度85℃,竹叶质量与85%乙醇体积的比为1∶20(g/mL),提取时间50 min;在以上优化的工艺条件下,长节箬竹竹叶总黄酮含量为2.23%.     

竹叶黄酮的抗氧化性及其心脑血管药理活性研究进展

介绍了竹叶黄酮的抗氧化性及其心脑血管药理活性相关的研究进展.1)体内体外实验表明,竹叶黄酮具有清除自由基、抗脂质过氧化、提升体内抗氧化水平的作用; 2)动物试验和临床试验表明,竹叶黄酮能显著降低动物及人体的血清甘油三酯含量, 升高高密度脂蛋白胆固醇含量; 3)药理研究表明,竹叶黄酮具有抗整体动物缺氧的作用、能有效扩张冠脉血管、增加冠脉流量,增加心肌收缩力、明显改善心肌缺血及缩小心梗范围,降低血小板聚集程度、有效抑制凝血和血栓形成,对脑缺血有一定的保护作用.竹叶黄酮具有作为防治心脑血管疾病的天然药物和膳食补充剂开发的潜力.     

HPLC测定丛生竹中总黄酮及(异)牡荆苷、(异)荭草苷的含量

以勃氏甜龙竹竹叶为原料,对其中竹叶黄酮的超声提取工艺进行研究,同时采用高效液相色谱法(HPLC)对勃氏甜龙竹、箬竹、浦竹仔及椅子竹中总黄酮及牡荆苷、异牡荆苷、荭草苷、异荭草苷的含量进行测定。结果表明,勃氏甜龙竹超声提取最佳的工艺为:甲醇作为提取溶剂、浓度为70%、料液比为1︰10(w︰v)、超声时间60min、温度40℃。在最佳提取条件下,勃氏甜龙竹中总黄酮得率能达到4.63%。采用高效液相色谱-外标法测定4种丛生竹中总黄酮,含量分别为0.795 2%、1.166 9%、0.092 6%、0.897 2%。勃氏甜龙竹、箬竹和椅子竹中均含有牡荆苷、异牡荆苷、荭草苷及异荭草苷,浦竹仔中仅含有牡荆苷和异牡荆苷。分析方法的建立,为丛生竹化学资源的利用奠定基础。     

竹叶挥发油化学成分及其抗氧化特性

采用水蒸气蒸馏法从黄金间碧竹、孝顺竹、毛竹和麻竹4种竹叶中提取挥发油,用气相色谱-质谱联用技术对4种竹叶挥发油化学成分进行分析和鉴定,共获得168个色谱峰,鉴定其中132种化学成分,并运用气相色谱面积归一化法确定各组分的相对含量;以TBHQ为对照品,采用DPPH法研究4种竹叶挥发油对自由基的清除作用.结果表明:采用水蒸气蒸馏法黄金间碧竹竹叶挥发油的得率最高(0.827%),而毛竹竹叶挥发油的得率仅为0.391%.4种竹叶挥发油的化学成分在含量和组成上不同,竹叶挥发油主要化学成分是3-甲基-2-丁醇,麻竹竹叶挥发油含量最高达到46.25%;其他主要化学成分有4-乙烯基-2-甲氧基-苯酚、己-2-烯醛、橙花叔醇、植物醇、苯乙醛、天竺葵醛、植酮、二氢猕猴桃内酯和异植物醇.4种竹叶挥发油均有较强的抗氧化活性,竹叶挥发油的抗氧化活性与挥发油的浓度呈正相关(r=0.91),其中黄金间碧竹竹叶挥发油的抗氧化活性最强(IC50=2.705mg·mL-1),孝顺竹竹叶挥发油抗氧化活性较低(IC50=3.442mg·mL-1).综合研究结果表明,竹叶挥发油具有较高的应用价值,可作为食品和药品的功能性组分进一步开发和利用.     

不同柿种柿叶维生素C和酚类物质的差异

对15个柿栽培品种和5个柿属野生种叶中Vc和酚类物质的测定结果表明,野生种的年平均Vc、总酚、黄酮平均含量均高于栽培种,其中Vc含量排序为:野生种>涩柿品种>甜柿品种。除罗田甜柿和老鸦柿外所有材料5月份Vc含量均超过10mg·g-1(FW),大部分甜柿品种的Vc含量随季节的变化显著下降,其它(品)种则变化幅度较小。烘干(60℃)后的柿叶Vc平均保存量只有鲜叶的8 88%。总酚量最高的是野生种,年平均达44 91mg·g-1(FW),所有(品)种的季节变化规律大体上与Vc相同。柿叶中共检测到8种酚酸,其中没食子酸、肉桂酸、咖啡酸和香豆酸分别占酚酸总量的48%、21%、12%和10%。柿叶中黄酮类物质年均含量都在1 7mg·g-1(FW)以上,其中油柿超过11mg·g-1(FW),且季节变化不大。柿叶有效成分的开发可根据利用目的选用适当的(品)种或季节。     

竹织叶野螟危害对毛竹叶片次生物质含量的影响

研究了毛竹受竹织叶野螟危害后,竹叶次生物质含量的变化.结果表明,毛竹受竹织叶野螟危害后,竹叶中单宁和黄酮含量增加,总酚含量下降.说明毛竹次生代谢物质和抗虫性之间有密切的关系.     

刺玫果总黄酮的双水相萃取工艺及其抗氧化能力

为探索刺玫果总黄酮的乙醇-硫酸铵双水相(添加氯化钠)萃取工艺及其体外抗氧化性。采用单因素和正交试验法对刺玫果总黄酮的双水相萃取工艺进行了优化;并通过测试刺玫果总黄酮提取液对二苯基苦基肼自由基(DPPH·)、羟基自由基(·OH)、超氧阴离子自由基(O-2·)、亚硝酸盐、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵自由基阳离子(·ABTS+)的清除率和还原力,评价其抗氧化活性。结果表明:在乙醇体积分数27%、硫酸铵质量浓度0.21 g/m L、刺玫果提取液体积分数22%、氯化钠加入量为2.0 g的最佳工艺条件下刺玫果总黄酮平均萃取率为91.81%。刺玫果总黄酮提取液对·ABTS+、·OH和O-2·具有显著的清除能力,当总黄酮质量浓度分别为0.12、0.30和0.60 g/L时,对·ABTS+、·OH和O-2·的清除率分别为90.27、89.60%和96.73%,其清除能力均强于Vc;对DPPH·、亚硝酸盐具有一定的清除能力,但弱于Vc;刺玫果总黄酮提取液具有一定的还原能力。     

果子狸生熏腿的加工技术

采用果子狸剥皮后的整只后腿经低温腌制、整形、烟熏等形式而制成。成品为半干制品,外形像乐器琵琶,其外表肉色呈咖啡色,内部淡红色,皮金黄色,生熏腿是西式肉制品中的一个高档品种,肉质略带轻度烟熏味,清香爽口。     

Liquefaction of bamboo, preparation of liquefied bamboo adhesives, and properties of the adhesives

This study investigated the liquefaction of bamboo in phenol, which involved the effects of weight ratios of phenol to bamboo, amount of catalyst, temperature, etc. The study showed that liquefaction could be accomplished with a phenol to bamboo weight ratio of 2–1: 1, a 5% catalyst of HCl or BF₃, and a temperature of 115°C. Liquefied bamboo formaldehyde (BLF) resin adhesive for exterior use could be obtained with a phenol to formaldehyde molar ratio of 1:1.6–2.0. The curing behavior of BLF resin adhesive, studied by TG-DSC and IR analyses, showed that BLF resin adhesives had a lower curing temperature than PF adhesives but had the same characteristic trough in IR spectra as PF adhesives. __________ Translated from Chemistry and Industry of Forest Products, 2004, 24(3) [译自: 林产化学与工业, 2004, 24(3)]     

保鲜竹笋的调味笋罐头加工工艺的研究

在亚林所石全太研究员研究成果的基础上,利用近10吨毛竹笋、红竹保鲜竹笋为原料,研制开发出四大系列调味竹笋罐头─—辣味笋、骨汁辣味笋、雪菜笋、油焖笋,并制定出其产品的质量检测感官、理化及微生物指标。     

红烧轮叶党参加工工艺的探讨

以轮叶党参为主要原料，对红烧轮叶党参菜肴的加工工艺、产品配方及冻藏稳定性进行了研究。得出其最佳的配方为：胡萝卜10％、色拉油10％，食盐2％，酱油3％，糖3％，料酒3％，葱2％，姜2％，蒜2％，花椒0．5％，大料0．5％，味精0．5％；其最佳的油炸条件为180℃3min，煮制的条件为160℃15min；这样的产品可在-18℃下冻藏4个月，产品的感官品质仍然很好。     

Neuroprotective effect of naringin by modulation of endogenous biomarkers in streptozotocin induced painful diabetic neuropathy

Diabetes mellitus is a serious debilitating epidemic affecting all social strata in developing as well as developed countries. Diabetic neuropathy is most common of secondary complications associated with diabetes mellitus and is characterized by slowing of nerve conduction velocity, elevated pain, sensory loss and nerve fiber degeneration. The aim of the present investigation was to evaluate the neuroprotective effect of naringin against streptozotocin (STZ) induced diabetic neuropathic pain in laboratory rats. Four weeks after intraperitoneal injection of STZ resulted in significant decrease in mechano-tactile allodynia, mechanical hyperalgesia, thermal hyperalgesia and motor nerve conduction velocity. Activity of endogenous antioxidant like superoxide dismutase as well as membrane bound inorganic phosphate enzyme was also found to be significantly decreased. It not only caused neural cell apoptosis but also enhanced lipid peroxide, nitrite, and inflammatory mediators' (TNF-α) level. Chronic treatment with naringin (40 and 80mg/kg) for 4 weeks significantly and dose dependently attenuated the decrease in level of nociceptive threshold, endogenous antioxidant and membrane bound inorganic phosphate enzyme. It also decreased the elevated levels of oxidative-nitrosative stress, inflammatory mediators as well as apoptosis in neural cells significantly and dose dependently. The important finding of the study is that, the naringin-insulin combination not only attenuated the diabetic condition but also reversed the neuropathic pain, whereas insulin or naringin alone only improved hyperglycemia but partially reversed the pain response in diabetic rats. Thus, naringin is a potential flavonone bearing antioxidant, antiapoptotic and disease modifying property acting via modulation of endogenous biomarker to inhibit diabetes induced neuropathic pain.     

Sulfuric acid bleaching of kraft pulp 1: Bleaching of hardwood and softwood kraft pulps

To develop a new nonchlorine bleaching technology, hardwood and softwood kraft pulps, before and after oxygen-alkali predelignification, were treated with dilute sulfuric acid solutions (pH 1.0-1.8) at 100°C for 1 h and then extracted with aqueous sodium hydroxide at 70°C for l h. Hardwood kraft pulp was successfully bleached. The delignification selectivity was similar to that seen with oxygen-alkali bleaching; and it was greatly enhanced by the addition of sodium nitrate and sodium nitrite. The sulfuric acid bleaching can replace the presently adopted oxygen and chlorine stages if the additives are allowed. This bleaching process was also effective for oxygen-bleached hardwood kraft pulp, but it was less effective for softwood kraft pulp and oxygen-bleached softwood kraft pulp. The effectiveness of the addition of sodium nitrate and sodium nitrite was more apparent for softwood kraft pulp than for hardwood kraft pulp.Part of this report was presented at the 7th International Symposium on Wood and Pulping Chemistry, Beijing, July 1993     

板栗有机多元专用肥的研制与应用

根据板栗需肥特性与优质高产要求,以配方施肥以与平衡技术为基础,在适应的Ｎ、Ｐ、Ｋ三要素配方的基础上,加入有机肥料、无机肥料添加剂（含中、微量元素）,研制出板栗有机多元专用肥。其Ｎ、Ｐ、Ｋ有机质与腐植酸养分总量超过４０％。施用后比对照增产７７．８％,板栗中氨基酸、蛋白质、脂肪、总糖等营养成分明显增加。并且具有增强抗性、减少落果、提高产量、改善品质、促进土壤改良等多种功效。     

杉木指接集成板的生产工艺与技术

采用南方速生杉木制造指接集成板,从杉木材性、加工工艺、设备性能、材料利用率、生产成本、产品质量和市场需求等方面出发,研究和分析了南方速生杉木制造指接集成板的特点和应掌握的技术问题.结果表明,这种杉木有高胶接强度和浸渍剥离强度,但自身剪切强度较低.采取恰当的工艺与技术,用南方速生杉木可以生产出满足市场需求的较高质量的指接集成板.