金边黄杨叶、茎挥发油成分分析及抗肿瘤活性研究

分析研究金边黄杨叶、茎挥发油的主要成分及其抗肿瘤活性。以超临界二氧化碳萃取金边黄杨叶、茎挥发油,利用气相色谱-质谱联用技术(GC-MS),经过NIST08谱库检索对比,从中分别,叶挥发油鉴定31个化合物,主要成分有:棕榈油酸(17.11%)、苯甲醛(10.66%)、(Z)-3-己烯-1-醇(8.93%)、正十六烷酸(7.92%)、苯甲醇(6.99%)、肉豆蔻酸(6.13%)、正十五烷酸(6.06%)。茎挥发油鉴定33个化合物,主要成分有:丙二醇单甲醚(12.20%)、正十六烷酸(5.52%)、6,6-二甲基二环[3.1.1]庚-2-烯-2-甲醇(5.17%)、2,4-二叔丁基苯酚(5.08%)。应用四甲基偶氮唑盐(MTT)法检测抗癌活性,结果叶挥发油对对肺癌细胞A549和胃癌细胞SGC-7901抑制最强,其IC50值分别为2.77μg/m L、3.78μg/m L,对比研究表明正十五烷酸是叶挥发油中抑制两种癌细胞的主要活性成分。     

藤萝花脂溶性成分分析

利用气相色谱-质谱联用(GC-MS)技术对藤萝花的脂溶性成分分析,首次研究藤萝花的脂溶性成分。结果显示,从藤萝花中共鉴定出44种成分,占色谱总流出峰面积的59.74%,主要由酸类和酯类组成,其主要成分有正十六烷酸(14.80%)、亚油酸(13.85%)、顺式-13-十八碳烯酸(6.93%)、十八烷酸(5.10%), 2-单亚油酸甘油酯(4.48%)和9-[(Z)-2-[(1Z, 3Z)-3-己烯叉]亚环丙基]壬酸2-羟基-1-(羟甲基)(4.87%),可见,藤萝花脂溶性成分的研究为其进一步的开发利用提供了科学依据。     

槟榔油的分离及GC-MS 分析

采用硅胶柱层析、气相色谱- 质谱(GC-MS)联用方法对槟榔油进行分离纯化和成分分析,确定以正已烷-丙酮(8:2,V/V)体系作为槟榔油分离的洗脱液。分离纯化后的槟榔油经GC-MS 测定共有18 种脂肪酸,其中含量较高的有十四烷酸(肉豆蔻酸)26.08%、十八碳烯酸(油酸)24.20%、十八碳二烯酸(亚油酸)22.70%、十六烷酸(棕榈酸)14.09% 和十二烷酸(月桂酸)7.87%。可见,槟榔油可开发为具有调节血脂、延缓衰老的保健食品。     

竹叶挥发油中主要化合物的抑菌作用

选取毛竹叶挥发油中含量相对较高的化合物,即正二十三碳烷、雪松脑和十六烷酸3种单体化合物,采用双层平板打孔法,研究不同质量浓度的3种单体及各单体的混合物溶液对革兰氏阳性菌(枯草芽孢杆菌)、革兰氏阴性菌(大肠杆菌、假单胞杆菌、黄杆菌)及酵母菌等菌株的抑菌功效。结果表明:雪松脑具有较强的抑菌功效,十六烷酸次之;3种单体的混合溶液亦具有较好的抑菌功效,且普遍高于单体单独作用的效果:正二十三碳烷和雪松脑混合后抑菌功效明显高于正二十三碳烷单独作用的效果,略低于雪松脑溶液的单独作用;正二十三碳烷和十六烷酸的混合液抑菌功效比正二十三碳烷溶液单独作用效果好,略低于十六烷酸溶液的单独作用;雪松脑和十六烷酸的混合液比十六烷酸溶液单独作用的抑菌功效高,略低于雪松脑溶液的单独作用;3种单体溶液混合后抑菌功效不仅比正二十三碳烷溶液和十六烷酸溶液单独作用的高,而且也比单体两两混合液的抑菌效果明显。     

GC-MS分析中药白及中脂肪酸成分

目的气相色谱-质谱联用(GC-MS)分析中药材白及中脂肪酸成分。方法采用石油醚索氏抽提法提取白及中脂肪油,经三氟化硼乙醚甲醇溶液甲酯化处理,用GC-MS测定脂肪酸组成。结果共分离出13个峰,确定了12种脂肪酸成分,主要为亚油酸(9,12-十八碳二烯酸),棕榈酸(十六烷酸),山嵛酸(二十二烷酸),木蜡酸(二十四烷酸),肉豆蔻酸(十四烷酸)等。结论此法操作简单、迅速、灵敏、准确度高,可满足白及药材中脂肪酸成分的分析需要。     

辽东湾产蛤蜊中脂肪酸组成的GC/MS分析

以无水乙醚为溶剂提取蛤蜊油,经皂化和甲酯化后利用气相色谱-质谱联用技术对其脂肪酸组成进行了分析和鉴定,共分离鉴定出15种脂肪酸,占总脂肪酸含量的89.76%。其中饱和脂肪酸的相对含量为50.77%,主要为十六烷酸(软脂酸)和十八烷酸(硬脂酸);不饱和脂肪酸的相对含量为38.99%,主要为二十碳五稀酸(EPA)、9-十六碳烯酸和11-二十碳烯酸。     

食品添加剂不饱和脂肪酸单甘酯的测定与表征

建立了食品添加剂不饱和脂肪酸单甘酯定性表征和定量分析方法。采用气相色谱-质谱法对不饱和脂肪酸单甘酯和甘油进行定性、定量分析,结果表明:不饱和脂肪酸单甘酯主要含有5种脂肪酸,即十六烷酸(棕榈酸)、十八碳二烯酸(亚油酸)、十八碳烯酸(油酸)、十八烷酸(硬脂酸)、二十二烷酸(山嵛酸)。     

密蒙花挥发油成分气相色谱-质谱分析

研究密蒙花中的挥发性化学成分.采用水蒸气蒸馏,用气相色谱-质谱法进行分析,按峰面积归一化法求出挥发性化学成分的相对含量.分离出48个峰,鉴定了30个化合物.结论:已鉴定的化合物包括酮、酸、烷烃、酯、醇、烯烃、联苯及杂环等8类化合物.其中酮类化合物占总色谱流出峰面积的21.52%.酸类占14.83%,烷烃类占12.24%,酯类占10.55%,醇类占10.18%.其主要组分有6,10,14-三基-2-十五烷酮(18.18%),n-十六酸(13.13%),二十八烷(4.25%),邻苯二甲酸丁基2-乙基己基酯(3.74%),3,4-二乙基-1,1-联苯(3.4%),三十五烷(3.39%),(-)-匙叶桉油烯醇(3.25%).     

乳酸菌代谢物中黄嘌呤氧化酶抑制剂的筛选

乳酸菌及其代谢产物以其天然、良好的抗菌活性以及安全、可靠等优点被广泛使用。目前从乳酸菌代谢物中筛选黄嘌呤氧化酶(XOD)抑制剂鲜有报道。本文将分子对接技术与高效液相色谱(HPLC)技术结合,筛选乳酸菌代谢产物中的XOD抑制剂。试验结果表明:选取的5株乳酸菌的代谢产物均对XOD有较强地抑制作用;上清液中有机酸类物质抑制了XOD活性。使用分子对接技术将代谢物中的有机酸类物质与XOD进行对接,并选择其中4种验证其对XOD的抑制作用。结果显示:二氢咖啡酸(DHCA)、16-羟基十六烷酸、十二烷二酸(DDA)、4-十二烷基苯磺酸对XOD有不同程度的抑制作用,其中16-羟基十六烷酸表现出较强的XOD抑制效果。     

山桃花挥发油的化学成分分析

采用气质联用法初步探索山桃花挥发油的化学成分和相对含量。优化条件为:气相进样口温度250℃,进样量1μL,分流比10∶1,流速1m L/min,程序升温,起始温度50℃,以10℃/min升温至150℃,以1.5℃/min升温至200℃,以3℃/min升温至280℃,辅助加热器温度280℃。首次得到15种主要成分。肉豆蔻酸(1.06%)、棕榈酸甲酯(2.29%)、棕榈酸(35.83%)、3,5,11,15-四甲基-3-羟基-1-十六烯(1.87%)、正二十四烷(20.75%)、正二十一烷(13.81%)等是山桃花挥发油的主要成分。     

利用铬污泥制备铬鞣剂的研究

本文研究了铬污泥经重铬酸钠氧化制备再生铬鞣剂的工艺方案：首先用硫酸对铬污泥进行预处理,过滤收集滤液,再经重铬酸钠消解后加入葡萄糖和亚硫酸氢钠溶液还原,然后用氢氧化钙调节pH值、碱度,最后干燥制成。实验得出铬鞣剂的最佳制备条件：16％的硫酸溶解铬污泥;0．8％的Na2Cr2O7消解其中的有机物。用所得铬鞣剂对羊皮进行鞣制,蓝湿革收缩温度均大于等于98℃,手感丰满、柔软。     

Thermophilic two-stage dry anaerobic digestion of model garbage with ammonia stripping

To avoid the inhibition of methane production by ammonia that occurs during the degradation of garbage, anaerobic digestion with prior ammonia production and subsequent stripping was investigated. In the ammonia production phase, the maximum ammonia concentration was approximately 2800 mg N/kg of total wet sludge in the range of 4 days of sludge retention time, indicating that only 43% of total nitrogen in the model garbage was converted to ammonia. The model garbage from which ammonia was produced and stripped was subjected to semi-continuous thermophilic dry anaerobic digestion over 180 days. The gas yield was in the range of 0.68 to 0.75 Nm(3)/kg volatile solid, and it decreased with the decrease of the sludge retention time. The ammonia-nitrogen concentration in the sludge was kept below 3000 mg N/kg total wet sludge. Microbial community structure analysis revealed that the phylum Firmicutes dominated in the ammonia production, but the community structure changed at different sludge retention times. In dry anaerobic digestion, the dominant bacteria shifted from the phylum Thermotogae to Firmicutes. The dominant archaeon was the genus Methanothermobacter, but the ratio of Methanosarcina increased during the process of dry anaerobic digestion.     

Dry and wet fractionation of plant proteins: How a hybrid process increases yield and impacts nutritional value of faba beans proteins

A combined dry and wet fractionation process is proposed to extract faba bean proteins with lower environmental impact. This fractionation process allowed to recover 87% of the total seeds proteins (92% of dehulled seeds proteins). This is achieved through the production of two protein concentrates (54 and 61% protein content w/w DM). After dry fractionation, wet extraction was performed on the protein-depleted fraction. The presented process consumed less energy and 5.5 times less water per kg extracted proteins, compared to traditional one-step wet extractions. Some anti-nutritional factors contents were also evaluated. Equivalent levels of phytic acid (about 11 mg/g), trypsin inhibitor activity (about 13 trypsin inhibition unit/g) and polyphenols (about 6 mg gallic acid equivalent/g) were observed in the 2 protein-rich fractions. These levels are mainly equivalent to those found after usual dry and wet one-step extractions. Significant differences of calcium, iron and zinc contents were observed between the 2 protein-rich fractions, causing a 30 to 50% difference between those fractions in terms of phytic acid/minerals ratio. Antinutritional factors content in the protein-rich fractions are equivalent to levels found in traditional legumes but still higher than existing recommendations.     

Estimates of the atmospheric deposition of sulfur and nitrogen species: Clean Air Status and Trends Network 1990-2000

The Clean Air Status and Trends Network (CASTNet) was established by the U.S. EPA in response to the requirements of the 1990 Clean Air Act Amendments. To satisfy these requirements CASTNet was designed to assess and report on geographic patterns and long-term, temporal trends in ambient air pollution and acid deposition in order to gauge the effectiveness of current and future mandated emission reductions. This paper presents an analysis of the spatial patterns of deposition of sulfur and nitrogen pollutants for the period 1990-2000. Estimates of deposition are provided for two 4-yr periods: 1990-1993 and 1997-2000. These two periods were selected to contrast deposition before and after the large decrease in SO2 emissions that occurred in 1995. Estimates of dry deposition were obtained from measurements at CASTNet sites combined with deposition velocities that were modeled using the multilayer model, a 20-layer model that simulates the various atmospheric processes that contribute to dry deposition. Estimates of wet deposition were obtained from measurements at sites operated bythe National Atmospheric Deposition Program. The estimates of dry and wet deposition were combined to calculate total deposition of atmospheric sulfur (dry SO2, dry and wet SO4(2-)) and nitrogen (dry HNO3, dry and wet NO3-, dry and wet NH4+). An analysis of the deposition estimates showed a significant decline in sulfur deposition and no change in nitrogen deposition. The highest rates of sulfur deposition were observed in the Ohio River Valley and downwind states. This region also observed the largest decline in sulfur deposition. The highest rates of nitrogen deposition were observed in the Midwest from Illinois to southern New York State. Sulfur and nitrogen deposition fluxes were significantly higher in the eastern United States as compared to the western sites. Dry deposition contributed approximately 38% of total sulfur deposition and 30% of total nitrogen deposition in the eastern United States. Percentages are similar for the two 4-yr periods. Wet sulfate and dry SO2 depositions were the largest contributors to sulfur deposition. Wet nitrate, wet ammonium, and dry HNO3 depositions were the largest contributors to nitrogen deposition.     

壳聚糖涂膜对鲜切菠萝蜜的保鲜作用

本文通过壳聚糖对鲜切菠萝蜜进行涂膜处理,研究保质期内还原糖含量、总酸含量、水分含量的变化,分析壳聚糖涂膜对干苞和湿苞菠萝蜜的保鲜效果。结果表明：在3±1℃的条件下贮藏15 d,涂膜鲜切菠萝蜜的还原糖的变化速率较小,均小于未处理组。涂膜湿苞和干苞的还原糖含量分别降低了3.58%和3.81%,而未处理组还原糖含量降低了4.77%。贮藏到第6 d时,涂膜处理的湿苞和干苞含水量都达到最低值,对照组的含水量为65.96%,湿苞和干苞的含水量分别为72.60%和73.81%,总酸量分别降低了0.13%和0.15%,未处理组总酸含量降低了0.23%。壳聚糖涂膜处理能够延缓菠萝蜜的后熟,对湿苞的保鲜效果优于对干苞的保鲜效果。     

大黄鱼鱼卵脂质含量及脂肪酸组成分析

用氯仿-甲醇法提取大黄鱼鱼卵的粗脂肪,经甲酯化处理,用气相色谱法对其脂肪酸的组成进行分析。结果显示大黄鱼鱼卵湿基总脂肪含量达19.6%,干基总脂肪含量达44%,磷脂占总脂肪比例为61.2%,胆固醇占总脂肪比例为3.2%,而且大黄鱼鱼卵还含有丰富的ω-3PUFA多不饱和脂肪酸,其EPA和DHA之和达到了25.5%。     

柞木波动干燥技术研究

探讨了在满足干燥质量的前提下利用温度梯度加大木材内部水分传导从而降低木材含水率梯度,提高干燥温度的方法。通过实验确定了高温高湿处理木材的温度及正常干燥时间和温度。     

Segregation of biomass in cyclic anaerobic/aerobic granular sludge allows the enrichment of anaerobic ammonium oxidizing bacteria at low temperatures

A cyclic anaerobic/aerobic bubble column reactor was run for 420 days to study the competition for nitrite between nitrite oxidizing bacteria (NOB) and anaerobic ammonium oxidizing bacteria (Anammox) at low temperatures. An anaerobic feeding period with nitrite and ammonium in the influent followed by an aerated period was applied resulting in a biomass specific conversion rate of 0.18 ± 0.02 [gN(2) - N · gVSS(-1)· day(-1)] when the dissolved oxygen concentration was maintained at 1.0 mgO(2) · L(-1). An increase in white granules was observed in the reactor which were mainly located at the top of the settled sludge bed, whereas red granules were located at the bottom. FISH, activity tests, and qPCR techniques revealed that red biomass was dominated by Anammox bacteria and white granules by NOB. Granules from the top of the sludge bed were smaller and therefore had a higher aerobic volume fraction, a lower density, and consequently a slower settling rate. Sludge was manually removed from the top of the settled sludge bed to selectively remove NOB which resulted in an increased overall biomass specific N-conversion rate of 0.32 ± 0.02 [gN(2) - N · gVSS(-1) · day(-1)]. Biomass segregation in granular sludge reactors gives an extra opportunity to select for specific microbial groups by applying a different SRT for different microbial groups.     

Structure characterization and adsorption properties of pyrolyzed sewage sludge

Sewage sludges produced from wastewater treatment plants continue to set environmental problems in terms of volume and way of reuse. Thermal treatment of sewage sludge is considered as an attractive method in reducing sludge volume, and at the same time, it produces reusable byproducts. This paper deals with porous carbonaceous materials production from sewage sludge by pyrolysis (or carbonization) process with a goal of different industrial applications. Carbonization experiments were carried out on two kinds of sludge, namely viscous liquid sludge and limed sludge by varying carbonization temperature between 400 degrees C to 1000 degrees C. The porous structure and surface chemistry of the materials obtained were characterized using nitrogen adsorption, scanning electron microscopy, elemental analysis, Boehm titration, and pH of zero point of charge determination. The results show that basic character of the carbonized residues increases with increasing carbonization temperature. Then, carbonization allows specific surface area and pore volumes to be developed. Carbonized viscous liquid sludge and carbonized limed sludge are mainly mesoporous in nature, with specific surface areas reaching about 100 m2 g(-1) and 60 m2 g(-1), respectively. Finally, adsorption experiments, in aqueous solution, were carried out and show that carbonized viscous liquid sludges and limed sludge remove effectively the metallic ion Cu2+, acid and basic dyes, and phenol. Pyrolyzed sludges properties seem to be encouraging for the preparation of activated carbon by physical activation process.