Folin-Ciocalteu分光光度法测定夏枯草总酚含量的研究(英文)

通过采用Folin-Ciocalteu试剂,以没食子酸为对照品,用紫外可见分光光度法,研究测定夏枯草中总酚含量。结果表明,在装有样品的10 mL容量瓶中依次加入Folin-Ciocalteu试剂0.5 mL,20%Na2CO31.7 mL,室温放置60 min后,在波长660 nm或760 nm测定吸光度。多酚质量浓度在0～10.3μg/mL范围内与吸光度有良好的线性关系,回归方程在660 nm为Y=94.542X-0.0067,R2=0.9999,加样回收率为101.7～105.0%;760 nm为Y=101.13X-0.0191,R2=0.9990,加样回收率为105.1～107.6%。本研究在稳定性、准确性和重复性方面都具有较好的实验结果,可为夏枯草多酚的定量分析提供方法参考。     

Folin-Ciocalteu比色法测定桦褐孔菌多酚的条件优化

以没食子酸为标准品,通过正交试验和单因素实验研究了Folin-Ciocalteu 比色法测定桦褐孔菌中多酚含量的适宜条件。结果表明,优化后的显色条件为Folin-Ciocalteu试剂用量0.3mL、10% Na2CO3溶液0.6mL,25℃时避光反应30min,于750nm处测定其吸光值。多酚质量浓度在0.0032－0.0256mg/mL范围内与吸光值有良好的线性关系。根据拟合的线性回归方程对桦褐孔菌多酚进行定量测定,野生桦褐孔菌和人工培养桦褐孔菌中多酚含量最高分别为（72.05±0.08）mg/g、（52.76±0.06）mg/g（n=6）。不同加标水平的加标回收率测定实验获得的平均回收率为98.95%,RSD为1.27%。该法测定桦褐孔菌多酚具有快速、准确,稳定性强,重现性好,精密度高的特点,可应用于实际样品的测定。     

Folin-Ciocalteu比色法测定铜藻中褐藻多酚含量的研究

以没食子酸为标准品,使用福林酚(Folin-Ciocalteu)试剂,通过紫外-可见分光光度法,对铜藻中褐藻多酚的含量进行了测定。结果表明,测定波长为760 nm,显色试剂Folin-Ciocalteu的用量为1.25 m L,0.1 g/m L Na2CO3溶液用量为4.0 m L,定容至10 m L,显色温度为30℃,反应时间为60 min,多酚含量在15~50μg/m L范围内与吸光度呈良好线性关系,回归方程为Y=0.0138X+0.0267,R2=0.9993。本测定方法的平均回收率为96.18%,相对标准偏差(RSD)为2.44%。该方法的稳定性、重现性、精密度以及加标回收率的相对标准偏差均符合要求,可用于铜藻中褐藻多酚含量的测定。按照本方法测定铜藻中褐藻多酚的平均含量为17.36 mg/g(RSD=1.25%)。     

Folin-ciocalteu比色法测桑叶中多酚含量

采用以没食子酸为标准,研究了Folin-ciocalteu比色法测定桑叶中多酚含量的适宜条件。结果表明,桑叶提取液在Folin-ciocalteu试剂2.0 mL、20%Na2CO3溶液5.0 mL、反应温度30℃、反应时间2 h的条件下,测定其760 nm处的吸光值,多酚浓度在10.0～100.0 mg/L范围内与吸光值呈良好的线性关系;稳定性、精密度、重现性和回收率实验的相对标准偏差为0.2969%～2.502%。该法是一种简便、快速、准确测定桑叶多酚含量的可靠方法。     

反相高效液相色谱法测定不同品种花椒中芦丁和槲皮素的含量

目的:建立RP-HPLC测定花椒中芦丁与槲皮素含量的方法,并对不同种花椒的中芦丁与槲皮素含量进行测定与比较。方法:Zorbax Eclipse C18色谱柱(150 mm×4.6 mm,5μm),流动相∶甲醇-0.4%磷酸(50∶50);流速1 mL/min;检测波长:360 nm;柱温25℃。结果:芦丁在0.25~5.0μg,r=0.999 9峰面积与质量浓度呈良好的线性关系;平均回收率为99.1%,RSD为4.3%(n=3)。槲皮素在0.25~0.5μg,r=0.999 9峰面积与质量浓度呈良好的线性关系;平均回收率为111.2%,RSD为5.1%(n=3)。结论:该方法可用于花椒中芦丁和槲皮素的测定。测定结果表明,韩城红花椒中芦丁含量最高,茂汉红花椒次之,四川青花椒较少,云南青花椒最低。槲皮素在韩城红花椒中含量较高,在其他三种花椒中差别不大。     

花椒果皮中总黄酮与多酚的积累及其抗氧化活性研究

以7年生花椒为试材,研究不同生长时期花椒果皮的总黄酮、总多酚含量的变化以及二者与抗氧化能力的关系.结果显示:(1)在花椒果实发育过程中,花椒果皮黄酮与多酚均有积累,总黄酮含量随果实的成熟程度不断增加,于成熟期(8月1日)黄酮含量达到最大值(164.14 mg/g);但多酚含量在果实发育早期迅速上升,于6月30日达到最大值(77.17 mg/g)后快速下降,至成熟期(8月1日)多酚含量为46.23 mg/g.(2)不同时期的花椒果皮均具有还原力及羟基自由基清除能力,且二者随果实生长的增加而提高,且总黄酮、多酚含量均与还原力和羟基自由基清除能力之间呈显著正相关关系,相关系数分别为0.977、0.960和0.917、0.933.研究表明,成熟花椒果皮中总黄酮含量达到最高,多酚含量也较高,而且黄酮和多酚类物质是花椒果皮抗氧化活性的主要功效成分.     

两种精油熏蒸处理对金针菇贮藏品质的影响

为了开发高效的食用菌绿色保鲜剂,以新鲜的白色金针菇为供试材料,以花椒精油和丁香精油为供试熏蒸剂,分别在常温（25±1）℃和低温（4±1）℃条件下开展了适用于金针菇保鲜的精油种类和浓度的筛选试验,并对金针菇贮藏期内的感官评价、失重率、呼吸强度、褐变度、多酚氧化酶（PPO）活性、苯丙氨酸解氨酶（PAL）活性、丙二醛（MDA）以及总酚含量进行了测定。结果显示,常温（25±1）℃条件下用0.1 mL·kg-1花椒精油和0.5 mL·kg-1丁香精油保鲜效果优于其他处理,且有统计学意义（P<0.05）,0.1 mL·kg-1花椒精油和0.5 mL·kg-1丁香精油处理组感官评分分别高于对照组23.4%和27.8%,二者均能够抑制金针菇褐变、减轻腐败变质,且有统计学意义（P<0.05）;在低温（4±1）℃贮藏试验中发现,0.1 mL·kg-1花椒精油和0.5 mL·kg-1丁香精油均能有效抑制呼吸强度和PPO活性的升高（P<0.05）,其呼吸高峰较对照组分别降低了28.3%和39.6%;贮藏15 d后,精油处理组PPO活性较对照组分别降低了8.2%和16.6%;精油处理有效降低了MDA含量的产生,保持着较高的总酚含量、减轻腐烂褐变的程度。第15天时,对照组MDA含量为1.75 μmol·g-1,而花椒精油和丁香精油处理组MDA含量分别比对照组低0.15、0.40 μmol·g-1,丁香精油处理组显著低于花椒精油处理组和对照组（P<0.05）。研究结果表明,0.1 mL·kg-1花椒精油和0.5 mL·kg-1丁香精油均对金针菇采后贮藏保鲜效果显著,其中,0.5 mL·kg-1丁香精油的保鲜效果最明显,在15d的贮藏期内,金针菇依然保持着良好的品质,而对照组已经轻微褐变,部分开始腐烂。研究结果为花椒精油和丁香精油应用于金针菇采后贮藏保鲜提供了理论依据。     

高效液相法测定香菇菇柄麦角甾醇的含量

采用高效液相色谱法(High performance liquid chromatography,HPLC)建立了测定菇柄麦角甾醇的含量测定方法。确定提取过程中皂化剂的种类和醇碱比后,将样品皂化,萃取后蒸干溶剂,乙醇定容测定。采用Phe-nomenex-C18色谱柱,V(流动相甲醇)∶V(水)=98∶2,流速1.0 mL/min,检测波长282 nm。结果表明:麦角甾醇线性回归方程为Y=9E+9×106X-8919.9(X:质量浓度,mg/mL),R2=0.998 9,0.01~0.30 mg/mL范围内线性关系良好,回收率为97.31%~101.95%。与紫外分光光度法所测结果比较,HPLC法测定菇柄中麦角甾醇含量灵敏、快速、准确,适用菇柄中麦角甾醇的含量测定。     

有柄石韦总多酚含量测定及其超声提取工艺优化

为优选有柄石韦Pyrrosia petiolos中总多酚超声提取工艺,采用Folin-Ciocalteus比色法对总多酚进行含量测定,通过单因素和正交试验,对提取工艺参数进行优化。结果表明,没食子酸对照品在浓度为1～10 mg·L-1范围内,与吸光度呈良好线性关系（y=2.406x-0.012,R=0.9994）,有柄石韦总多酚的最佳提取工艺条件为：55%乙醇,料液比1∶10（W/V）,超声提取60 min,超声提取温度75℃,总多酚提取率为21.47 mg·g-1。     

稻曲病菌厚垣孢子中cAMP提取条件优选

探究稻曲病菌(Ustiloginoidea virens(Cooke.) Takahashi)黑色(休眠)与黄色(非休眠)厚垣孢子中的环磷酸腺苷(cAMP)最佳提取条件,为进一步的研究cAMP功能奠定基础.采用超声-水浴法对cAMP进行浸提,按3因素3水平正交设计,用高效液相色谱法检测cAMP含量;在设定V(甲醇)∶V(0.05 mol/L KH2PO4)=20∶80、流速为0.8 mL/min、检测波长为254 nm、进样量为20 μL的条件下,以黄绿色厚垣孢子为提取样品,其提取cAMP效果最佳组合条件:超声破碎时间10 min(功率400 W、间歇时间2 s),水浴温度80℃,物料比为1∶100,提取的cAMP为6.827 6 μg/mL.在此最佳条件下,测定出黄色厚垣孢子的cAMP为12.805 0±0.533 2μg/mL,黑色厚垣孢子的cAMP为4.171 7±0.097 1μg/mL.此结果表明,由黄色转换为黑色,其厚垣孢子的cAMP含量显著降低.     

广西十个不同产地的两面针中活性成分的分析

采用HPLC法对广西十个不同产地的两面针中具有抗肿瘤活性的氯化两面针碱和具有镇痛活性的 L-芝麻脂素的含量进行了分析和比较。发现在不同产地的两面针中氯化两面针碱和L-芝麻脂素的含量差别 都较大,广西百色的两面针中氯化两面针碱含量和L-芝麻脂素的含量均最高,氯化两面针碱0．467％,L-芝麻 脂素0．160％;广西金秀的两面针中氯化两面针碱含量和L-芝麻脂素的含量均最低,氯化两面针碱0．0490％, L-芝麻脂素0．0370％。分析的色谱柱为HYPERSIL BDS C18,测定氯化两面针碱的条件为,流动相乙腈: 0．02 mol／L KH2PO4溶液(34:66),流速为1．0 mL／min,柱温40℃,检测波长329 nm,进样量为20μL;测定 L-芝麻脂素的条件为,流动相乙腈:水(50:50),流速为1．0 mL／min,柱温40℃,检测波长287 nm,进样量为 20μL。该研究为两面针在抗肿瘤药物和镇痛等方面的开发利用提供了可靠的理论依据,具有重要应用价值。     

A model for formulation of protein assay.

The principle of the protein assay using the reaction of an alkaline copper-protein complex with the Folin-Ciocalteu phenol reagent has been investigated. In contrast to the long-established Lowry method, a stable and rapid protein assay is developed without a buffering agent in alkaline copper solution. In the absence of a buffering agent, the reaction pH drops relatively rapidly and moves the reaction toward a more stable pH. When the reaction of alkaline copper-protein complex with Folin-Ciocalteu reagent is started at around pH 11.7, the reaction color absorbance reaches a plateau in approximately 10 min and remains stable to allow a reliable measurement of the absorbance. In the absence of the buffering agent sodium carbonate, the alkaline copper solution is also stable for months. The principle of the protein assay is presented as a model that can be used to formulate protein assays of desired specification.     

SEC-HPLC法测定重组人生长激素注射液中苯酚含量

采用SEC-HPLC法测定重组人生长激素注射液中苯酚的含量。色谱柱为TSK G2000SWxL（7.8×300mm,5μ）,流动相为PB（pH值7.0）-异丙醇（97∶3）,流速0.6 mL/min,检测波长214nm,柱温25℃。苯酚在0.10～1.00 mg/mL浓度范围内线性关系良好,r=0.99915;最低检测限为0.5 ng/mL;平均回收率101.48%,RSD=0.58%（n=9）;3批重组人生长激素注射液中苯酚的含量分别为2.98、3.02和2.96 mg/mL,分别为标示量的99.33%、100.67%和98.67%。SEC-HPLC法环保、准确、快速、可靠,可用于重组人生长激素注射液中苯酚含量的测定。     

Anti-Inflammatory and Anti-Osteoclastogenesis Activities of Different Kinds of Zanthoxylum bungeanum Seed Oil in Vitro

Our previous study has exhibited that one kind of Zanthoxylum bungeanum seed oil (ZSO), extracted from Zanthoxylum bungeanum seed, had inhibitory effects on osteoclastogenesis. However, the anti-osteoclastogenesis activities of different kinds of ZSO are scarcely reported. Since inflammation is related to bone loss and osteoporosis, in this study, three kinds of ZSO, Zanthoxylum schinifolium Siebold et Zucc seed oil (ZSSO), Zanthoxylum armatum DC. seed oil (ZDSO) and Zanthoxylum bungeanum maximum seed oil (ZBSO), were obtained with Soxhlet extraction and their fatty acid constituents were detected by GC-FID. RAW264.7 macrophages induced by lipopolysaccharide (LPS) were used to evaluate the inhibitory effects of three kinds of ZSO on inflammation via detecting the expression levels of inflammatory factors by RT-qPCR. Moreover, RANKL-induced osteoclastogenesis was applied to demonstrate the anti-osteoclastogenesis activities of them through tartrate-resistant acid phosphatase (TRAP) staining and RT-qPCR. The GC-FID results exhibited that the highest constituent in ZSSO and ZDSO was oleic acid (OA) and palmitoleic acid (PLA), respectively. While linoleic acid (LA) and α-Linolenic acid (ALA) in ZBSO were dominant. At the concentration of 0.5 μL/mL, all three kinds of ZSO could decrease the expression levels of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 beta (IL-1β) in LPS-induced macrophages. At the concentration of 0.25 μL/mL, only ZSSO could decrease the expression levels of iNOS and COX-2, which implied the inhibitory effects of ZSSO were stronger than other ZSOs. The number of RANKL-induced osteoclasts and the expressions of nuclear factor kappa-B (NF-κB), TNF-α and IL-6 in the cells were decreased after being treated with ZSOs at the concentration of 0.5 μL/mL, while the number of RANKL-induced osteoclasts after treated with ZBSO were less than those treated with other ZSOs, this indicated that the anti-osteoclastogenesis effect of ZBSO were stronger than other ZSOs. In conclusion, the fatty acid compositions of three major kinds of ZSO were compared and the content of unsaturated fatty acids especially ω-3 polyunsaturated fatty acids in ZBSO were the highest among them. All ZSOs tested had anti-inflammatory and anti-osteoclastogenesis activities. And their anti-osteoclastogenesis effects might be related to the suppression of the NF-κB pathway.     

The Oxidation of Phenol by Ferrate(VI) Andferrate(V). A Pulse Radiolysis and Stopped-Flow Study

Potassium ferrate. K₂FeO₄, is found to oxidize phenol in aqueous solution (5.5 ± pH ± 10) by a process which is second order in both reactants; -d[Fe^vt]/dt=ki[Fe^VI][phenol], kI = 10⁷M^-1s^-1. Product analysis by HPLC showed a mixture of hydroxylated products, principally paraquinone. and biphenols that indicate that oxidation of phenol occurs by both one-electron and two-electron pathways. The two-electron oxidant. producing both para- and ortho-hydroxylated phenols is considered to be ferrate(V) which is itself produced by the initial one-electron reduction of ferrate(VI). The rate of ferrate(V) reaction with phenol was determined by pre-mix stopped flow pulse-radiolysis and found to be k7 = (3.8 ± 0.4)± 10⁵M^-1s^-1.     

枯草芽孢杆菌B47菌株高产抗菌物质的培养基及发酵条件优化

枯草芽孢杆菌Bacillus subtilis B47菌株为番茄内生细菌, 也是玉米小斑病拮抗菌, 能产生对玉米小斑病菌有强烈抑制作用的抗菌物质。以B47菌株发酵液的无菌滤液对玉米小斑病菌的抗菌活性为检测指标, 测定B47菌株产抗菌物质培养所需的最佳碳、氮源和无机盐, 并通过正交试验法对该菌株产抗菌物质的培养基配方和摇瓶发酵条件进行优化。研究结果表明, B47菌株产抗菌物质最佳碳、氮源和无机盐分别为蔗糖、酵母浸膏和MgSO4·7H2O, 最优培养基是YSB (Yeast extract-sucrose-beef extract)培养基, 其配方为: 蔗糖2%, 酵母浸膏2%, 牛肉浸膏1.5%, MgSO4?7H2O 0.06%, FeSO4·7H2O 0.000 9%, 最优发酵条件组合为: 30 °C, pH 7.0, 170 r/min摇床培养6 d, 接种量为1%, 装液量为40 mL/200 mL。     

链脲佐菌素致胰岛NO自由基损伤模型的建立和应用

以链脲佐菌素Streptozotocin（简称STZ）为糖尿病的诱因,以NO自由基含量为响应指标,建立了体外小鼠胰岛水平糖尿病药物筛选模型。当STZ作用浓度在0～50mmol/L内变化时,培养液中被检测到的NO大部分是来源于STZ溶于水后释放出的,而很小一部分是由胰岛培养物自身释放的,后者稳定在30～35mmol/L之间。另一方面,NO含量与胰岛素分泌量的剂量关系表明NO的增加伴随着胰岛素分泌量的下降,这标志着NO对胰岛功能的氧化性损伤,从而验证了NO作为该模型响应参量的可靠性。最终确定STZ致胰岛NO自由基损伤模型中STZ的作用浓度为5.0mmol/L,此时NO含量和胰岛素分泌量分别为STZ未加入前的10.81倍和0.43倍。最后应用该模型,快捷地考察了不同铬含量的魔芋葡甘露寡糖铬络合物（简称KOSCr）清除NO自由基的能力。