新会陈皮中黄酮类化合物提取工艺的研究

以水和乙醇溶液为提取介质分别提取了新会陈皮中的黄酮类化合物,通过单因素试验和正交试验验确定了提取新会陈皮黄酮类化合物的最佳工艺条件。结果表明:乙醇作为新会陈皮黄酮类化合物提取介质的提取效果明显优于纯水;采用乙醇作为提取溶剂时,影响新会陈皮中黄酮类化合物提取率的因素由大到小依次为乙醇浓度>液料比>提取时间>提取温度;最佳工艺条件为乙醇浓度80%、液料比1∶45、温度70℃、提取时间3 h,最佳提取工艺的新会陈皮黄酮得率为0.80%,此外,罗岗橙皮、梅州蜜柚皮、芦柑皮采用最佳工艺提取的黄酮含量分别为0.94%、0.30%和1.19%。

缩醛基毛冬青提取化合物R4对大鼠急性心肌缺血/再灌注损伤的影响

目的观察缩醛基毛冬青提取化合物R4对在体大鼠急性心肌缺血/再灌注损伤(I/R)的影响,并探讨其保护作用机制。方法建立大鼠心肌缺血/再灌注模型,采用试剂盒测定再灌注40min后血清肌酸激酶(CK)、肿瘤坏死因子(TNF-α)、IL-1Β的水平,观察心肌梗死范围,采用凝胶电泳法测定核转录因子-κB(NF-κB)的活性,采用试剂盒测定测定心肌组织超氧化物(SOD)活性及丙二醛(MDA)含量。结果缺血20min再灌注40min后模型组及用药组的血清TNF-α、IL-1β、CK水平明显高于假手术组,且缩醛基毛冬青提取化合物R4组及维拉帕米对照组明显低于模型组。再灌注40min后模型组及用药组的梗死范围明显增加,NF-κB表达明显增高,且缩醛基毛冬青提取化合物R4组及维拉帕米对照组明显低于模型组。再灌注40min后模型组及用药组的SOD明显降低,MDA明显增高,缩醛基毛冬青提取化合物R4组及维拉帕米对照组MDA明显低于模型组,SOD明显高于模型组,有统计学意义。结论缩醛基毛冬青提取化合物R4对缺血再灌注心肌的保护作用与其显著缩小心肌梗死面积,降低肌酸磷酸激酶,降低MDA同时提高SOD,减少心肌细胞内TNF-α、IL-1β、NF-κB蛋白的表达有关。

缩醛基毛冬青提取化合物R4对麻醉犬心功能与血流动力学的影响

目的研究缩醛基毛冬青提取化合物R4对麻醉犬心功能与血流动力学的影响。方法采用麻醉犬开胸,测定心脏血流动力学参数,并分离冠状动脉左旋支,放置探头测量冠脉血流量,同步测量心输出量。结果缩醛基毛冬青提取化合物R4(0.5mg/kg、1.0mg/kg、2.0mg/kg)可降低麻醉犬的血压,减少心肌耗氧量以及减慢心率,降低左室舒张末期压,左心室内压最大上升和下降速率,同时增加冠脉血流量。结论缩醛基毛冬青提取化合物R4通过减少心肌耗氧量,降低左室舒张末期压及左心室内压最大上升和下降速率,使冠脉流量增加等环节发挥改善麻醉犬心功能与血流动力学的作用。

缩醛基毛冬青提取化合物R4对缺氧/复氧大鼠心肌细胞的保护作用

目的:探讨缩醛基毛冬青提取化合物R4对缺氧/复氧损伤心肌细胞的保护作用及其机制。方法:采用原代培养的新生大鼠心肌细胞建立缺氧/复氧损伤模型,实验分为正常细胞培养组和缺氧/复氧损伤模型组、缺氧/复氧损伤+缩醛基毛冬青提取化合物R4(5、10、20μmol/L)组和缺氧/复氧损伤+verapamil(5μmol/L)组。用黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)的活性,硫代巴比妥酸显色法测定丙二醛(MDA)含量,MTT染色法测定线粒体脱氢酶活性改变,化学比色法测定乳酸脱氢酶(LDH)活性变化,Griess法测定一氧化氮(NO)的含量。结果:缩醛基毛冬青提取化合物R4可显著提高缺氧/复氧损伤心肌细胞内SOD的活性及细胞内线粒体脱氢酶活性,能显著抑制LDH的活性、MDA的生成以及提高NO的含量,并能明显抑制心肌细胞凋亡。结论:缩醛基毛冬青提取化合物R4具有明显抗缺氧/复氧损伤、保护心肌细胞的作用。

我国钨提取冶金的现状与未来

目前,我国钨提取冶金工业在中国共产党的英明领导下,随着共和国四十多年的发展而经历了从无到有,由小到大的发展过程,尤其是在改革开放十多年来发展更快。就钨的初级产品或中间产品而言,其品种、数量及技术水平都取得了很大的成绩,不但能生产国内自用的产品,而且能生产高纯的仲钨酸铵、钨酸钠、三氧化钨、蓝色氧化钨等出口产品,其质量标准优于国外同类产品,向世界真正的钨大国迈进。本文着重论述我国从钨矿物原料的分解至钨纯化合物提取冶金的现状与未来。

牡丹叶总黄酮提取工艺条件优化研究

用分光光度法对总黄酮的含量进行测定。采用单因素和正交实验的方法探讨牡丹叶中黄酮类化合物的最佳提取工艺。研究结果表明，芦丁在0．0125-0．0625mg／mL范围内浓度与吸光度有良好的线性关系。最佳提取工艺条件：25倍量60％乙醇在80℃条件下加热回流提取3h。黄酮提取率为2．27％，干粉黄酮纯度为5．27％。

正交试验法和响应面法优选蒲公英根甾醇提取

优化超声波浸提蒲公英根甾醇的工艺条件。试验控制1.00 g样品用20 mL乙醇在超声波清洗机里进行浸提,设计正交试验和响应面试验研究甾醇提取率随着乙醇浓度、超声提取时间、超声提取温度三个因素水平变化而变化的规律。正交优化分析得出最佳提取工艺下,能提出甾醇含量为46.01 mg/g,此时乙醇浓度为80%,提取时间为20 min,提取温度为60℃。响应面分析结果为乙醇浓度87.42%、提取时间10.83 min、提取温度59.97℃,这时每克蒲公英根提取甾醇的含量最高为67.26 mg。该结果表明响应面法工艺条件下得到的蒲公英根甾醇提取率高于正交试验所得。

缩醛基毛冬青提取化合物R4对缺血缺氧心肌的保护作用

目的:研究缩醛基毛冬青提取化合物R4对缺血缺氧心肌的保护作用,以便为缩醛基毛冬青提取化合物R4的临床新用途提供实验依据。方法:采用小鼠常压耐缺氧实验、夹闭气管小鼠心电消失时间、垂体后叶素所致大鼠心肌缺血模型及大鼠冠脉结扎所致的心肌缺血模型,观察缩醛基毛冬青提取化合物R4对缺血缺氧心肌的保护作用。结果:缩醛基毛冬青提取化合物R4(1.0、2.0、4.0 mg/kg)均能显著延长小鼠常压耐缺氧条件下的存活时间,延长夹闭气管小鼠心电消失时间,缩醛基毛冬青提取化合物R4(0.75、1.5和3.0 mg/kg)能拮抗垂体后叶素引起的心电图变化,并能明显降低结扎冠脉所致大鼠的心肌梗塞范围。结论:缩醛基毛冬青提取化合物R4对缺血缺氧心肌具有明显保护作用,其效应与剂量呈相关性,其机制可能是通过扩张冠脉,增加心肌的供血供氧而发挥抗心肌缺血的作用。

Application of Cellulase-assisted Method to Extract Flavonoids from Plants

The extraction mechanisms of cellulase-assisted extraction technology in extracting flavonoids were summarized, as wel as its application in extracting flavonoids from the plants of Leguminosae, Ginkgoaceae, Rutaceae and Labiatae. In addition, the progress in the extraction of flavonoids by combining cellulase-assisted extraction technology and other technologies, such as cellulase-ultrasonic assisted extraction and cellulase-microwave assisted extraction, were described.

南瓜叶多酚对PVA复合薄膜抗氧化性能的影响

为了提高南瓜叶的高价值利用,以多酚提取率和DPPH自由基清除率为指标,优化提取南瓜叶多酚的条件。以PVA为基材、南瓜叶多酚为添加剂,采用溶液流延的方法制备一系列不同南瓜叶多酚添加量的南瓜叶多酚/PVA复合薄膜,进一步利用力学性能测试、水蒸气透过率测试、抗氧化能力、透光率/雾度、热重测试等测试方法,研究提取液含量对PVA薄膜性能的影响。综合分析表明,南瓜叶多酚化合物提取最佳条件为料液比1:16、乙醇的浓度85%、提取的温度60℃、提取时间为2 h。与纯PVA薄膜相比,含不同体积分数南瓜叶多酚的聚乙烯醇膜均具有一定的抗氧化性及较好的透明性,并且,水蒸气透过率增大,力学性能有小幅降低。

Solubilization of small molecules from coal and the resulting effects on the pore structure distribution

The solubilization of small molecules from coal by solvent extraction and the resulting effects on the pore distribution of a low rank coal were studied. Samples were extracted, in succession, with petroleum ether and with CS2. Extract and residue fractions collected during the solubilization process were analyzed by FTIR and by surface area and porosimetry. The results show that an obvious inflection point exists that allows separating the dissolution sequence into stages. Small molecules are first extracted from the free state, then molecules trapped in micropores are extracted and, finally, molecules trapped in the coal-matrix network are extracted. This is indicated from the extraction yield curves. Chain-like carbonyl compounds, -OH (or -NH) containing compounds that are hydrogen bonded and phenolics dominate the petroleum ether extracts. Chain-like carbonyl components and ether compounds (aliphatic ethers and aromatic ethers) dominate the CS2 extracts. A solvent dissolution mechanism and the effect of small molecule extraction on the pore structure are put forward. Diffusion, dissolution, pore opening, pore shrinking or even collapsing caused by swelling, creating of new micropores, pore opening and, finally, colloidallization of some micropores occurs. In the later stages of the extraction the internal structure of the coal is colloidallized due to swelling and the pore number or volume is greatly reduced.

Human plasma protein binding of water soluble flavonoids extracted from citrus peels

The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold water,and higher total flavonoid contents were detected in the former extracts than the latter ones.All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals,which indicates the health benefits of the water extracts of citrus fruits peels.For DPPH radical,the IC50values of hot extract follow as Navel orange(NO)≈Mandarin orange(MO)< Lemon(LE)< Lo tangerine(LO)< Pomelo(PO),while the rank is NO< PO<LE≈MO<LO for ABTS radical.The HPLC results reveal that the kinds and contents of the flavonoids detected in the extracts are different among the species.MO extract has the most neohesperidin dihydrochalcone of 118.76 μmol/L and quercetrin of 211.81 μmol/L of which are much more than the rest extracts.Pomelo extract has the most plentiful flavonoids of naringin with a concentration of 303.28 μmol/L.The high contents of myricetrin and dihydromyricetin which both are potent free radical scavengers may explain the highest free radical scavenging activity of the NO extract.The plasma binding rates decrease with the increasing concentrations of flavonoids,and the flavonoids having plenty hydroxyl groups on both A ring and B ring of the molecular skeleton have relative higher plasma binding rates.In addition,the plasma binding rates of flavonoids with saturated C3-C4 bond decrease significantly with the increasing concentrations.

Identification of Volatile Compounds in Codfish(Gadus) by a Combination of Two Extraction Methods Coupled with GC-MS Analysis

Codfish is a kind of abyssal fish species with a great value in food industry. However, the flavor of codfish, especially the unpleasant odor, has caused serious problems in its processing. To accurately identify the volatile compounds in codfish, a combination of solid phase micro-extraction(SPME) method and simultaneous distillation extraction(SDE) method was used to extract the volatiles. Gas chromatography-mass spectrometry(GC-MS) along with Kovats indices(KI) and authentic standard compounds were used to identify the volatiles. The results showed that a total of 86 volatile compounds were identified in codfish, of them 24 were extracted by SDE, 69 compounds by SPME, and 10 compounds by both SDE and SPME. Seventy volatile compounds were found to have specific odors, of them 7 typical compounds contributed significantly to the flavor of codfish. Alcohols(i.e.,(E)-2-penten-1-ol and 2-octanol), esters(i.e., ethyl butyrate and methyl geranate), aldehydes(i.e., 2-dodecenal and pentadecanal) contributed the most to fresh flavor while nitrogen compounds, sulphur compounds, furans, as well as some ketones(i.e., 2-hydroxy-3-pentanone) brought unpleasant odor, such as fishy and earthy odor. It was indicated that the combination of multiple extraction methods and GC-MS analysis can enhance the accuracy of identification, and provide a reference for the further study on flavor of aquatic products.

Antialgal and Antilarval Activities of Bioactive Compounds Extracted from the Marine Dinoflagellate Amphidinium carterae

Abstract With the global ban on the application of organotin-based marine coatings by the International Maritime Organization, the development of environmentally friendly, low-toxic and nontoxic antifouling compounds for marine industries has become an urgent need. Marine microorganisms have been considered as a potential source of natural antifoulants. In this study, the antifouling potential of marine dinoflagellate Amphidinium carterae, the toxic and red-tide microalgae, was investigated. We performed a series of operations to extract the bioactive substances from Amphidinium carterae and tested their antialgal and antilarval activities. The crude extract of Amphidinium carterae showed significant antialgal activity and the ECs0 value against Skeletonema costatum was 55.4 ~tg mL-1. After purification, the isolated bioactive substances （the organic extract C） exhibited much higher antialgal and antilar- val activities with ECso of 12.9μgmL-1 against Skeletonema costatum and LC50 of 15.1 μmL-1 against Amphibalanus amphitrite larvae. Subsequently, IR, Q-TOFMS, and GC-MS were utilized for the structural elucidation of the bioactive compounds, and a series of unsaturated and saturated 16- to 22-carbon fatty acids were detected. The data suggested the bioactive compounds isolated from Amphidinium carterae exhibited a significant inhibiting effect against the diatom Skeletonema costatum and Amphibalanus amphi- trite larvae, and could be substitutes for persistent, toxic antifouling compounds.

Bacterial Cellulose Film Containing Flavonoids from ＂Sarapee＂ （Mammea siamensis） Flower Extract Against Salmonella typhimurium TISTR 292

Bacterial cellulose film containing Sarapee （Mammea siamensis） flower extract to against Salmonella typhimurium TISTR 292 was studied. Crude ethanol extract of flower from Sarapee was passed through the column chromatography in order to separate the flavonoid. The flavonoid content was about 7.97 mg/mL. Bacterial cellulose film produced by ,4cetobacter xylinum TISTR 975 in coconut juice and subsequently to application of a containing different concentration of flavonoid for 12 h and followed by freeze dry The bacterial cellulose film containing Sarapee extract using disc diffusion assay was tested for antimicrobial activity. The result showed that bacterial cellulose film containing 1.2 mg/mL of flavonoid was highly against to S. typhimurium TISTR 292 and the inhibition zone was about 31.07 mm. Investigations of the effect of coating time on incorporation of flavonoid into cellulose film showed that long coating time （12 h） had the inhibition zone closely to short coating time （8 h） with the value of 29.60-30.13 mm. Stored the bacterial cellulose film at room temperature for 7 and 14 days found that the ability to be against S. typhimurium TISTR 292 decreased after 14 days and the inhibition zone was about 22.63 mm. The percentage of ability was remaining about 75.4. This study suggests that the bacterial cellulose film has a potential for use as antimicrobial in food applications.

Comparative Study on the Antibacterial Activity of Fresh and Fallen Leaves of Terminalia catappa L.

In the work reported here, the potential of different methods （cold and hot water, and ethanolic） of extraction of Indian almond （Terminalia catappa L.）, fresh and fallen leaves as an anti-bacterial agent was investigated. The hot water extract did not show any spectrum of activity against the selected bacteria while the cold water extract showed slight antibacterial activity suggesting that the effective components are heat labile. The ethanolic extracts of the leaves have higher antibiotic spectrum of activity than the cold water extract showing ethanol to be a better solvent in extracting the effective component. The fallen leaves seem to have a higher concentration of the effective component against the bacteria while ethanolic extract of the fresh leaves have similar spectrum of activity to Ciprofloxacin and Nitrofuratoin. These suggest that some effective components are lost when leaves fall off while some seem to increase in concentration. Fresh and fallen leaves contain tannin and flavonoids. In addition, the fallen leaves contain flavones. This might be responsible for the higher activity of fallen leaves extract observed against Pseudomonas and Staphylococcus spp. in our study. Combined use of extracts from fresh and fallen leaves broadened the spectrum of activity.

Preliminary Findings on Anticancer and Lymphocyte Stimulated Activities of Bioactive Compounds Extracted from Vietnam Carica papaya Leaves

In this study, the target bioactive compounds （e.g., alkaloids, flavonoids, saponins and other polar compounds） in Vietnamese Caricapapaya leaves were extracted. The cytotoxic activities of the papaya leaves extracts on the selected tumor cell lines, such as lung cancer cell line LU-1, carcinoma cell line KB, breast cancer cells MCF7 and leukemia cell line HL-60, were examined. Preliminary findings showed a high inhibitive activity of papaya leave extracts against the four tested tumor cell lines at the concentration of 100 μg/mL. Out of the bioactive compounds in papaya leaves extract, alkaloids showed the highest inhibitive activity （105.95% on MCF7 and 91.86% on LU-1）, followed by polar compounds （62.88% on LU-1 and 21.80% on KB）, and saponins （59.74% on MCF7 and 25.25% on LU-1）. Flavonoids has the lowest inhibitive activity on cell lines （e.g., 45.51% on MCF7 and 20.32% on LU-1）. Taken together, the results suggest that alkaloids have a relatively high inhibitive activity on the selected tumor cell lines and their stimulated concentration at 50% （IC50） values for on MCF7 and KB were 24.67 μg/mL and 33.56 μg/mL, respectively. However, the result pointed out the immunostimulatory ability of only polar compounds and saponins which could stimulate the growth of in vitro lymphocytes but not flavonoids and alkaloids. The SC50 （stimulated concentration at 50%） values of polar compounds and saponins were 287.87μg/mL and 192.99 μg/mL, respectively.

Characterization of Glycerol-Extractable Organic Matter from Etna Soils of Different Ages

We characterized humic acids （HAs） and glycerol-extractable organic fractions （GEOFs） extracted from four Andisols, taken from comparable soil-climate conditions on the east side of Mount Etna. The soils were formed on old lava （about 9000 years ago）, old tephra （about 8 700 years ago）, recent lava （about 2 600 years ago） and recent tephra （about 3600 years ago）. A part of the organic matter of the soils, deprived of HAs and fulvic acids （FAs）, was isolated by glycerol extraction. The GEOF can not be extracted with alkaline solutions, probably because it is closely bound to the mineral component of the soil. The characterization of the extracted organic fraction was carried out using elementary and functional group analysis and Fourier transform infrared （FT-IR） spectroscopy. About 20 extractions were necessary to extract the HA and FA from the older soils and about 10 extractions to extract them from the younger soils. Data showed that the CEOFs had a greater ash content and a smaller N content, as well as a greater presence of aliphatic compounds and carboxylic groups as compared to the HA extracted from the same soil. The GEOFs extracted from younger soils also had a lower yield, ash and COOH-group content, and were more aliphatic than the GEOF extracted from older soils. Finally, the GEOFs were more closely bound to the amorphous component of the soil （＇short-range＇ minerals） and consequently less subject to biodegradation.

Studies on Oxidation States of Cobalt Extracted from Soils with EDTA·HO Ac·NH_4OAc

A method determining di-and tri-valeht cobalt extracted from soils with EDTA·2HOAc·NH4OAc solution (pH 4.65) was developed based on the difference of the stability constants of Co(II)EDTA and Co(III)EDTA. Analytical results indicated that soil cobalt existed in both two oxidation states, i. e. , di-and tri-valent cobalt. Extractable di-valent cobalt in 60 soil samples collected from various soils in China ranged from 0.02 ppm to 3.54 ppm, with the mean of 0.62 ppm, and extractable tri-valent cobalt from 0.04 ppm to 27.65 ppm, with the mean of 2.93 ppm.