从柑橘皮中超声提取橙皮甙

在超声波作用下,用饱和Ca(OH)2水溶液浸提、盐酸酸析,从柑橘汁加工下脚料———柑橘果皮中提取橙皮甙。以精制橙皮甙收率为评价指标,利用正交实验L9(34)筛选最佳工艺条件为:超声提取温度25℃、超声时间30min、饱和Ca(OH)2溶液与柑橘皮质量比4∶1、超声频率25kHz。按优选的最佳工艺实验3次,精制橙皮甙平均收率达2 32%(为常规浸提法的1 61倍),相对标准偏差(RSD)为0 91%(n=3)。     

微胶囊红磷增效Ca(OH)2无卤阻燃聚乙烯

选用微胶囊红磷(MRP)作为PE/Ca(OH)2复合材料的增效阻燃剂,研究Ca(OH)2和MRP复配体系对PE/Ca(OH)2/MRP的力学性能及阻燃性能的影响,并采用扫描电镜观察PE/Ca(OH)2复合材料燃烧后炭层表面形貌.结果表明:添加Ca(OH)2与MRP的比值为30∶6时,PE/Ca(OH)2/MRP复合材料的氧指数达到27.5%,氧指数协效指数达到4%,水平燃烧试验通过FH-1级,且力学性能亦能得到保证,表明Ca(OH)2与MRP并用具有良好的阻燃增效作用.     

PE／Ca（OH）2／Mg（OH）2复合材料的阻燃性能初探

采用氧指数测试、水平燃烧性能测试、扫描电镜分析及热重分析等方法研究了不同配比 Ca(OH)_2/Mg(OH)_2的加入对聚乙烯(PE)复合材料[PE 用量为65%(质量分数,下同),Mg(OH)_2和 Ca(OH)_2总用量为35%]的氧指数、水平燃烧级别和燃烧后炭层表面形貌等燃烧性能的影响。结果表明,PE 复合材料氧指数达到24.5%,且其最快分解温度(T_(max))比纯 PE 滞后9.2℃,并促进致密炭层的形成。Ca(OH)_2与 Mg(OH)_2并用对 PE 阻燃性能有一定的协同增效作用,有望实现用廉价的 Ca(OH)_2对 Mg(OH)_2的替代。     

氢氧化钙对硫铝酸盐水泥-粉煤灰复合胶凝材料的水化影响

通过凝结时间、抗压强度和电阻率等分析手段,研究了Ca(OH)2对硫铝酸盐水泥-粉煤灰复合胶凝材料水化过程的影响.结果表明,掺入Ca(OH)2明显缩短了硫铝酸盐水泥-粉煤灰复合胶凝材料的凝结时间;当Ca(OH)2掺量为0.5%时,初凝时间最短,1 d、28 d强度均明显提高;当Ca(OH)2的掺量为2%时,28 d强度相比空白样提高了61.9%;掺入Ca(OH)2后,硫铝酸盐水泥-粉煤灰复合胶凝材料的1 d电阻率减小,随着Ca(OH)2掺量增大,电阻率逐渐减小,电阻率变化率极大值提前,说明Ca(OH)2加快了该复合胶凝材料的早期水化进程.XRD分析表明,掺入Ca(OH)2后,水化1 d时钙矾石的生成量增多,消耗无水硫铝酸钙的量增多;水化28 d时钙矾石的生成量相对变化较小,但强度明显增大,粉煤灰对硫铝酸盐水泥强度的贡献较为明显.     

恶草酮生产废水的化学氧化法处理研究

对恶草酮生产废水处理的双氧水氧化工艺进行了研究,为解决恶草酮生产废水处理提供技术参考。结果表明,氧化前添加Ca(OH)2的效果优于NaOH,且Ca(OH)2的添加量在1%~3%(w/v)范围内,废水COD下降值基本相同,而超过3%(w/v)时,不降反增;在双氧水处理240 min之内,废水的COD呈线性递减,而后几乎不变。采用优化的工艺:添加1%的Ca(OH)2预处理后,加入5%(v/v)H2O2氧化4 h,并用适量Ca(OH)2控制pH为5,而后添加适量的活性炭;恶草酮生产废水的COD由38 000 mg/L降至18 000 mg/L左右,COD的去除率约为55%。     

化学竞赛试题选登(下)

<正> (七)已知NaOH+Hcl=Nacl+H_2O+57.32千焦,而Ca(OH(?)(溶液)+H_2SO_4=CaSO_4+2H_2O+130.29千焦。导致130.29不等于2×57.32的因素是(八)从海水中提取金属镁的反应式为:Ca(OH)_2+Mg~(2+)(海水中)=Mg(OH)_2↓+Ca~(2+)     

协效阻燃剂对PE-HD/Ca(OH)2复合材料阻燃性能影响的研究

选用聚磷酸铵（APP）、三氧化钼（MoO3）、可膨胀石墨（EG）及微胶囊红磷（MRP）等作为高密度聚乙烯/氢氧化钙[PE-HD/Ca(OH)2]复合材料的协效阻燃剂,对PE-HD/Ca(OH)2复合材料的力学性能和阻燃性能进行了较深入的研究,并采用热重法研究了PE-HD/Ca(OH)2复合材料在氮气环境中的热失重过程。结果表明,少量协效剂（APP,MoO3,EG,MRP）的引入, 使PE/Ca(OH)2复合材料的氧指数分别比单独添加35 %Ca(OH)2时提高了2.38%、4.76%、7.14%和26.19%,且使其热氧化降解过程中生成更多的结实而稳定的炭层,起到一定的阻燃增效作用。     

不同抑制剂脱除方法对玉米秸秆水解液发酵的影响

通过向玉米秸秆水解液中添加活性炭、Ca(OH)2、活性炭+Ca(OH)2、亚硫酸钠和连二亚硫酸钠五种物质,研究了不同抑制剂脱除方法对水解液各组分及其对发酵的影响。结果表明,抑制剂脱除率由高到低依次为:活性炭+Ca(OH)2活性炭Ca(OH)2亚硫酸钠和连二亚硫酸钠,这与对还原糖造成的损失一致。对Clostridium beijerincii 8052发酵水解液的影响,由好到差依次为:Ca(OH)2活性炭活性炭+Ca(OH)2亚硫酸钠和连二亚硫酸钠。活性炭+Ca(OH)2的组合虽能最大程度去除糠醛、羟甲基糠醛和可溶性木素三种抑制剂,但从发酵结果来看,脱除抑制剂后的水解液中还存在其它未知组分对厌氧发酵产生一定影响。     

水煤浆固硫剂的研究

实验分析了Ca(OH)2、Mg(OH)2、CaCO3的固硫特性,根据不同固硫剂的热分解温度确定采用Ca(OH)2作主固硫剂用于环保固硫型水煤浆;分析了固硫剂的固硫机理,实验表明,当Ca/S=2.0时,水煤浆固硫率可达68.1%,解决了高硫煤的加工利用难题。     

单分散氢氧化钙/聚苯乙烯微球的制备与表征

以葡萄糖水溶液为反应介质,在氧化钙消化成氢氧化钙的过程中,加入苯乙烯单体和引发剂,采用原位悬浮聚合法成功制备了聚苯乙烯(PS)包覆氢氧化钙[Ca(OH)2]形成Ca(OH)2/PS微球.考察了葡萄糖水溶液、苯乙烯、稳定剂聚乙烯醇以及反应温度对单分散Ca(OH)2/PS微球的粒径及粒子分散系数的影响,得出较佳合成条件.在较佳条件下制备的Ca(OH)2/PS微球平均粒径为30～40 μm,粒子分散系数为0.08～0.10.扫描电镜照片表明,Ca(OH)2/PS具有良好的球形度,表面光滑、无破损.红外光谱表征显示,产物为Ca(OH)2/PS微球.     

橙皮苷的提取及其稳定性分析

为充分开发丰富的柑桔果皮资源,增加其经济附加值,采用碱溶酸析法提取椪柑果皮中橙皮苷,经D-101大孔树脂纯化,再运用紫外-可见光谱扫描法分析了温度、时间、氧气、光照、pH值、金属离子等对橙皮苷的稳定性影响。结果表明:该方法提取、纯化的橙皮苷,经HPLC法检测,纯度达到96.7%,得率1.92%。提纯的橙皮苷水溶液在75℃以下加热30 min之内,以及无氧、无光、酸性及中性条件下可保持其性能稳定;Fe³⁺、Cu²⁺对橙皮苷氧化起诱导加速作用,且在充分的氧气和光照下,特别是强光下,会引起其结构变化。     

Hesperidin Promotes Osteogenesis and Modulates Collagen Matrix Organization and Mineralization In Vitro and In Vivo

This study evaluated the direct effect of a phytochemical, hesperidin, on pre-osteoblast cell function as well as osteogenesis and collagen matrix quality, as there is little known about hesperidin’s influence in mineralized tissue formation and regeneration. Hesperidin was added to a culture of MC3T3-E1 cells at various concentrations. Cell proliferation, viability, osteogenic gene expression and deposited collagen matrix analyses were performed. Treatment with hesperidin showed significant upregulation of osteogenic markers, particularly with lower doses. Mature and compact collagen fibrils in hesperidin-treated cultures were observed by picrosirius red staining (PSR), although a thinner matrix layer was present for the higher dose of hesperidin compared to osteogenic media alone. Fourier-transform infrared spectroscopy indicated a better mineral-to-matrix ratio and matrix distribution in cultures exposed to hesperidin and confirmed less collagen deposited with the 100-µM dose of hesperidin. In vivo, hesperidin combined with a suboptimal dose of bone morphogenetic protein 2 (BMP2) (dose unable to promote healing of a rat mandible critical-sized bone defect) in a collagenous scaffold promoted a well-controlled (not ectopic) pattern of bone formation as compared to a large dose of BMP2 (previously defined as optimal in healing the critical-sized defect, although of ectopic nature). PSR staining of newly formed bone demonstrated that hesperidin can promote maturation of bone organic matrix. Our findings show, for the first time, that hesperidin has a modulatory role in mineralized tissue formation via not only osteoblast cell differentiation but also matrix organization and matrix-to-mineral ratio and could be a potential adjunct in regenerative bone therapies.     

Separation of selected bioactive compounds from orange peel using the sequence of supercritical CO2 extraction and ultrasound solvent extraction: optimization of limonene and hesperidin content

ABSTRACT

The orange peel (Citrus sinensis L.) from the variety Washington Navel was extracted by supercritical CO₂ (SC-CO₂) at different parameters. The extracts were analyzed by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). Limonene predominance was found (up to 89%). The principal oxygenated monoterpenes were linalool, α-terpineol, decanal, and (E)-citral. Ultrasound-assisted extraction was performed on the remaining solid residue (after SC-CO₂extraction) to obtain the extracts rich in hesperidin. The influence of different extraction parameters on hesperidin content (3.3–23.0 µg/mL) was determined. The prediction performance in optimizing the extraction yield of dominant compounds was studied by response surface methodology and artificial neural network.     

Protective effects of lemon flavonoids on oxidative stress in diabetic rats

The effects of lemon flavonoids, as crude flavonoids prepared from lemon juice, were investigated in diabetic rats. The oxidative stress of eriocitrin (eriodictyol 7-O-β-rutinoside) and hesperidin (hesperetin 7-O-β-rutinoside) on streptozotocin-induced diabetic rats was investigated. Diabetic rats were given a diet which contained 0.2% crude flavonoids, 0.2% eriocitrin, and 0.2% hesperidin. After the 28-d feeding period, the concentration of the thiobarbituric acid- reactive substance in the serum, liver, and kidney of diabetic rats administered crude flavonoids, eriocitrin, and hesperidin significantly decreased as compared with that of the diabetic group. The levels of 8-hydroxydeoxyguanosine, which is exchanged from deoxyguanosine owing to oxidative stress, in the urine of diabetic rats administered eriocitrin and hesperidin significantly decreased as compared with that of the diabetic rat group. Crude flavonoids, eriocitrin, and hesperidin suppressed the oxidative stress in the diabetic rats. These results demonstrated that dietary lemon flavonoids of eriocitrin and hesperidin play a role as antioxidant in vivo.     

陈皮中橙皮苷的提取工艺及优化研究

主要分析研究乙醇-吡啶混合溶剂超声浸提法提取陈皮中橙皮苷的最优条件。通过单因素试验去分析研究不同种因素对橙皮苷提取率的影响,并且在此基础上根据优化后的结果进行正交试验。其最佳工艺条件为料液比1:30,吡啶比例25%,提取温度为85℃,提取时间为25 min。采用该条件处理的橙皮苷经高效液相色谱法进行橙皮苷含量的测定,同时在此等优化条件下进行的正交试验,橙皮苷的提取率为3.83%,超声浸提法操作简便,快速,成本低,能应用于工业化生产和医学医药类研究。     

HPLC测定追风苏合丸中橙皮苷的含量

文章建立了HPLC法测定追风苏合丸中橙皮苷的含量。采用Kromasasil C18柱（150mm×4.6mm,5μm）,以甲醇：水：乙酸（40：60：4）为流动相,紫外检测波长为283mm。结果表明,橙皮苷在1.11-5．55μg;范围内呈良好的线性关系（r=0.9998）,橙皮苷平均回收率为97：6％,（n=6）,RSD为1．35％。该方法准确、可靠、重现性好,可适用于追风苏合丸中橙皮苷的含量测定。     

橙皮苷及其系列产品的提取工艺

选择不同的工艺条件从柑橘生理落果中提取粗制橙皮苷及从粗制橙皮苷中提取精制橙皮苷、甲基橙皮苷和地奥明 ,各产品收率和质量分数分别为 2 0 %、90 % ;6 0 %、98% ;4 0 %、94 % ;5 6 %、98 1%。同时阐述了反应机理和溶剂的选择     

Ultrafiltration behaviors of pectin-containing solution extracted from citrus peel on a ZrO<Subscript>2</Subscript> ceramic membrane pilot unit

Ultrafiltration experiments on a solution of pectin, hesperidin, and other mixtures extracted from citrus peels have been performed on a 500 l/min pilot scale crossflow ceramic membrane unit. A 30,000 molecular weight cut-off (MWCO) zirconia (ZrO₂) ceramic membrane with a total effective flow area of 0.5 m² was used in the process. The permeate flux for pure water and hesperidin showed linear relationship with transmembrane pressure (ΔP), but the flux for pectin solutions showed a curvilinear relationship with ΔP and represented a rapid increase with increasing ΔP before leveling-off. Similar behavior was observed by adding different amounts of hesperidin to these pectin solutions, but with much lower permeate flows. The formation of gel layers on the membrane surface is mainly responsible for the lower permeate fluxes. In addition, the permeate flux decrease faster at higher ΔP, since higher ΔP brought bigger flux at lower pectin concentration. Compared with the more than 90% retention rate of macromolecular pectin, pigment and other component have less than 20% retention rate. So, the decolorization, the separation and purification of pectin preparations could be achieved simultaneously through ultrafiltration with a ceramic membrane.     

橙皮苷对小鼠急性肝衰竭的保护作用及其机制

目的观察橙皮苷对脂多糖(Lipopolysaccharide,LPS)联合D-氨基半乳糖(D-Galactosamine,D-GalN)所致小鼠急性肝衰竭(Acute hepatic failure,AHF)的保护作用及其机制。方法小鼠腹腔注射LPS(50μg/kg)和D-GalN(800 mg/kg),复制急性肝衰竭模型,分别用橙皮苷(200 mg/kg)或橙皮苷(200 mg/kg)联合锌原卟啉IX(Zinc protoporphyrin IX,ZnPP)(45 mg/kg)干预。造模后6 h检测肝损伤程度和炎症反应强度,48 h统计小鼠死亡率。结果橙皮苷使AHF小鼠血清转氨酶(ALT和AST)水平下降,肝损伤减轻,生存率提高;血清白细胞介素-10(Interleukin-10,IL-10)水平和肝内血红素加氧酶-1(Heme oxygenase-1,HO-1)的表达较AHF小鼠明显增加,肝内HO-1酶活性明显增高;同时,使血清肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)水平、肝组织中Caspase-3蛋白酶和髓过氧物酶(Myeloperoxidase,MPO)活性较AHF小鼠明显降低。ZnPP不影响橙皮苷促进肝内HO-1酶表达,但通过抑制HO-1酶活性,使橙皮苷抗炎和肝损伤保护作用显著降低。结论橙皮苷主要通过诱导HO-1蛋白表达,使HO-1酶活性增强,从而使炎症反应和肝损伤减轻,对LPS联合D-GalN诱导的AHF产生保护作用。