柑橘类果汁中柚皮苷的分析

柚皮苷是柑橘汁中主要的苦味物质之一,其含量高低影响果汁的色泽、口味、稳定性等.通过分光光度法分析了9种柑橘类果汁中柚皮苷的含量,研究结果表明：胡柚汁中柚皮苷含量最高,为3.018 g/L,芦柑汁中柚皮苷含量最低,为0.310 g/L.在此基础上,用数学统计的方法对9种柑橘类果汁中柚皮苷含量差异性分析表明：脐橙汁与象山橘汁,椪柑汁与蜜柚汁柚皮苷含量无差别;椪柑汁比芦柑汁高,蜜柚汁比芦柑汁高,差异显著;其余种类果汁间柚皮苷含量均有极显著差异.     

-stablishment of Debittering Technique in 3oncentrated Orange Juice

[目的]研究脱苦工艺对浓缩橙汁的脱苦效果以及对果汁品质的影响。[方法]试验采用活性炭对浓缩橙汁进行脱苦,以橙汁中的柚皮苷（碱性二甘醇显色法）和柠檬苦素（对-二甲氨基苯甲醛显色法）的含量变化来表征浓缩橙汁的脱苦效果。[结果]通过单因素试验结合感官评定,确定了较适于橙汁的脱苦工艺：脱苦条件为常温20℃,活性炭用量35 g/L浓缩果汁（可溶性固形物含量50．5%）,搅拌时间20 min采用最佳工艺处理,得到的浓缩果汁中柚皮苷和柠檬苦素的脱除率分别为49．5%和73．5%。[结论]脱苦后浓缩橙汁苦味明显变淡,风味自然,口感适中。     

Determination of Naringin Content in Peel of Guangxi Citrus maxima (Burm.) Merr by HPLC

[Objectives]To establish a method for determining the naringin content in the peel of Guangxi Citrus maxima(Burm.)Merr.[Methods]The high performance liquid chro...     

渝产酸橙果实生长及有效成分积累动态的研究

[目的]研究渝产酸橙果实生长及有效成分积累动态规律,为确定川枳实、川枳壳适宜采收时期提供依据。[方法]通过定株取酸橙不同时期果实样品,测定其中辛弗林和柚皮苷含量。[结果]随着酸橙果实的生长,其重量、纵横径不断增加。前期折干率高,6月中旬以后,折干率降低。酸橙辛弗林含量随着果实生长而降低,7月以后降到0.3%以下,辛弗林产量以6月中旬时最大;酸橙柚皮苷含量先增大后减小,在6月中下旬时达到最大,7月下旬之后显著下降,柚皮苷产量7月中旬时达到最大值。[结论]渝产酸橙采收枳实以6月中旬前为宜,采收枳壳应在7月中旬前后最好。     

Reversing effect of naringin on cisplatin resistance in human lung cancer A549/DDP cells

AIM: To investigate the effect of naringin (NRG) on cisplatin (DDP) resistance in human lung cancer A549/DDP cells and its possible mechanism. METHODS: A549/DDP cells were cultured in vitro and treated with NRG and/or DDP at different concentrations for 24 h, and then the cell viability were measured by CCK-8 assay. The combination index (CI) of NRG and DDP were analyzed by Chou-Talalay method. The apoptosis rate was analyzed by flow cytometry. Western blot was performed to detect the protein levels of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), p-Akt, CXC chemokine receptor 4 (CXCR4), cleaved caspase-3, Bcl-2 and Bax.RESULTS: The protein levels of P-gp, MRP1, p-Akt and CXCR4 in the A549/DDP cells were higher than those in the A549 cells (P<0.05). The cell viability was remarkably reduced in a dose-dependent manner when A549/DDP cells were exposed to NRG and/or DDP (P<0.05), and the IC₅₀ values of NRG and DDP were 36.92 μmol/L and 129.77 μmol/L, respectively. When the inhibition rate exceeded 15%, NRG in combination with DDP produced a synergistic effect (CI<1). Combination treatment with NRG and DDP significantly induced apoptosis (P<0.05), up-regulated the protein levels of cleaved caspase-3 and Bax, and down-regulated the protein level of Bcl-2 (P<0.05). Meanwhile, NRG remarkably down-regulated the protein levels of P-gp, MRP1, p-Akt and CXCR4 in a dose-dependent manner (P<0.05). CONCLUSION: NRG may enhance the sensibility of A549/DDP cells to DDP most likely via up-regulating the protein level of Bax and down-regulating the protein levels of Bcl-2, P-gp, MRP1, p-Akt and CXCR4.     

沙田柚幼果中柚皮苷提取工艺研究

[目的]研究沙田柚幼果中柚皮苷的提取工艺。[方法]以柚皮苷的含量为指标,采用正交试验法进行优选,并用高效液相法测定柚皮苷含量。[结果]沙田柚幼果中柚皮苷最佳提取工艺为10倍量浓度50%乙醇,在50℃条件下提取1.5 h。[结论]该工艺提取率高、成本较低,可用于中试生产。     

高效液相色谱法测定柚叶中柚皮苷的含量

建立柚叶中柚皮苷含量的高效液相色谱分析方法。采用Kromasil C18色谱柱,流动相为甲醇∶水∶醋酸(35∶61∶4),流速为1.0ml/min,检测波长为283 nm。柚皮苷进样量在0.101~2.202μg线性良好,平均回收率101.27%,RSD为1.41%,所测样品的柚皮苷含量0.84%~1.25%,且嫩叶柚皮苷含量稍高于老叶。该法简便、快速、准确,可用于柚叶中柚皮苷的含量测定。     

柚苷和新橙皮苷氢化条件的研究

研究了用作甜味剂的柚苷和新橙皮苷氢化反应和氢气消耗动态以及氢压和催化剂对反应的影响，在反应开始的３０分钟，氢气消耗最快，到１２０分钟时氢耗停止，柚苷的耗氢量为４４．０ｃｍ＾３／ｇ，新橙皮苷的耗氢量为４８．８ｃｍ＾３／ｇ；氢气压力对产品的纯度和得率没有明显影响，钯炭的催化效果比骨架镍好，但这两种催化剂均可用于这类反应。     

β-环糊精对柑橘类果汁脱苦效果的研究

研究了β-环糊精(-βCD)对柑橘类果汁脱苦的效果。结果表明,在45℃下果汁中添加0.5 g/100 mlβ-环糊精作用90 min,对柑橘类果汁脱苦效果良好。     

高效液相色谱法测定去滞散中柚皮苷和新橙皮苷的含量

为了测定去滞散中枳壳的含量,采用C18柱（4.6×150mm,5μm）,在室温下,以乙腈-水（20：80,用磷酸调节pH值至3）为流动相,283nm为检测波长,流速为1.0ml?min-1,建立了反相高效液相色谱（RP-HPLC）测定方法。结果显示,柚皮苷在0.08～4μg范围内线性关系良好,R2 = 0.999 9,回收率为94.4% ~101.7%,RSD为2.23%;新橙皮苷在0.08～4μg范围内线性关系良好,R2 = 0.999 5,回收率为90.6% ~100.0%,RSD为2.85%。本方法简便、准确、快速,可用于控制去滞散中枳壳的含量。