Efficacy Evaluation of a Compound Plant Extract Used in Makeup Base

Cytological test and human skin test were used to study the antioxidant,anti-aging and moisturizing effects of a compound plant extract,and to evaluate its safety.The cytological test results showed that the compound extract could significantly scavenge the reactive oxygen species(ROS)generated by H2O2 stimulation and protect cells from oxidative damage.It can significantly inhibit the expression of matrix metalloproteinase-1(MMP-1).The results of human skin test showed that the moisture content of cheek stratum corneum,R2 value and Q1 value of skin elasticity were significantly improved after 28 days of continuous use of the Makeup Base product added with the compound plant extract.The Ra value,Rz value and Rt value of skin texture around eyes have been significantly improved,which shows that the product has the effects of improving the moisture content of stratum corneum,improving skin elasticity and diminishing the fine lines around the eyes;the product has good safety.

Distribution and sources of solvent extractable organic compounds in PM_(2.5) during 2007 Chinese Spring Festival in Beijing

The solvent extractable organic compounds （SEOC）, including n-alkanes, polycylic aromatic hydrocarbons, fatty acids, and dicarboxylic acids in PM2.5 during the 2007 Chinese Spring Festival in Beijing, were measured via gas chromatography-mass spectrometry for determining the characteristics and sources of these organic pollutants. The concentrations of total n-alkanes, PAHs, and organic acids before Chinese Spring Festival Eve （1025.5, 95.9, and 543.3 ng/m3, respectively） were higher than those after （536.6, 58.9, and 331.8 ng/m3, respectively）, n-Aalkanes and PAHs had much higher concentration in nighttime than those in daytime because of high relative humidity and low wind speed during the night. Combustion of coal and exhaust emission were major sources of n- alkanes. It could be concluded by the characteristic ratios that the primary source of PAHs in fine particles was the combustion of coal, but the combustion of gasoline was in the next place. The ratios of C18：0/C16 indicated the contribution of vehicular emissions to the fatty acids. Dicarboxylic and aromatic acids were abundant in daytime than in nighttime because these acids were secondary organic acid and the photochemical degradation of aromatic hydrocarbons was the main source.

An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L.

In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g.

Optimization of Extraction Conditions of Some Phenolic Compounds from White Horehound (<i>Marrubium vulgare</i>L.) Leaves

This research was aimed to optimize the extraction conditions of three phenolic compounds: total phenolics, flavonoids and condensed tannins, from White Horehound’s leaves (Marrubium vulgare L.). Distilled water and different organic solvents such as: methanol, ethanol and acetone, were used, with various concentrations (20% - 80%, v/v), temperatures (20&deg;C - 60&deg;C) and extraction times (30 - 450 min). Results showed that the maximum total phenolics amounts (293.34 ± 14.60 mg gallic acid equivalent/g dry weigh), were obtained with 60% aqueous methanol at 25&deg;C for 180 min;total flavonoids (79.52 ± 0.55 mg catechin equivalent/g dry weigh) with 80% aqueous methanol at 20&deg;C for 450 min, and condensed tannins (28.15 ± 0.80 mg catechin equivalent/g dry weigh) with 60% aqueous acetone at 50&deg;C and for 180 min. ANOVA test showed the significant effect (***P < 0.001) of the extraction conditions tested on phenolic compounds. The Principal Component Analysis (PCA) exhibited the positive effect of low temperatures on total phenolics and flavonoids extraction, and the effect of high temperatures on the condensed tannins extraction. The Response Surface Methodology (RSM) provided predicted values of extraction conditions and maximum polyphenols amounts similar to those obtained experimentally.

Extraction of Total Phenolic Compounds, Flavonoids, Anthocyanins and Tannins from Grape Byproducts by Response Surface Methodology. Influence of Solid-Liquid Ratio, Particle Size, Time, Temperature and Solvent Mixtures on the Optimization Process

The current work concerns the optimization process of phenolic compounds solid liquid extraction from grape byproducts at high temperatures and short incubation times. The effect of five experimental parameters (solidliquid ratio, particle size, time, temperature and solvent mixture) mostly believed to affect the extraction process was undertaken. A first response surface methodology experimental design was used to optimize the solid-liquid ratio and milling time parameters. A second design was used for the optimization of the quantitative and qualitative parameters. The quantitative parameters studied are: total phenolic compounds, flavonoid content, total monomeric anthocyanin composition and tannin concentration. The qualitative parameters analyzed are: antiradical activity and antioxidant capacity. The second design was based on the use of time, temperature and solvent mixture as optimization parameters. The assays were first conducted separately revealing the best experimental conditions for the maximization of each response variable alone. A simultaneous response surface methodology of all the responses taken together was then conducted, showing the optimal extraction conditions to be: 93 minutes at 94?C and in 66% ethanol/water solvent. The maximal response values obtained for each parameter are: Total Phenolic Compounds yield (5.5 g GAE/100g DM), Flavonoid Content (5.4 g GAE/100g DM), Total Monomeric Anthocyanin yield (70.3 mg/100g DM), Tannin Concentration (12.3 g/L), Antiradical Activity (67.3%) and Total Antioxidant Capacity (393 mgAAE/L). All of the optimal values were acquired at 3 mL/g solid-liquid ratio and 6.8 min milling time. The obtained extracts could be used as natural bioactive compounds in several industrial applications.

Low Cost Process for Phenolic Compounds Extraction from Cabernet Sauvignon Grapes (<i>Vitis vinifera</i>L. cv. Cabernet Sauvignon). Optimization by Response Surface Methodology

Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from grape berries using response surface methodology was here achieved. Cabernet Sauvignon (CS) wine grapes (Vitis vinifera L. cv. Cabernet Sauvignon) are a rich source of anti-radical phe- nols, extractable as dietary supplements. However, efficiency of extraction strongly depends on specific experimental conditions. In this work, the comparison between two extraction mixtures, Acetone/Water (A/W) and Methanol/Water (M/W) and the effects of three critical variables—Extraction Time (between 8 and 88 h), Extraction Temperature (between 1?C and 35?C) and Solvent Content (between 63% and 97%)—on Phenolic Compounds Yield (PCY) and Monomeric Anthocyanins Yield (MAY) were studied using Response Surface Methodology (RSM). Process conditions maximizing the PCY were found to be 87% A/W solvent content, after 88 h incubation at 26?C, and those of the MAY were found to be 97% M/W solvent content, after 8 h incubation at 1?C. In addition, chromatographic profiles of extracts showed very different affinities of the phenolic compounds families to the experimental conditions employed. This process advantages are: low percentage of organic solvent used, high quality of extracted molecules thanks to low temperature treatment, very low energy consumption and low cost of needed machinery. At industrial scale, it may be used as promising technique for the extraction of bioactive compounds from plant or byproduct material such as from wine or grape juice industries.

Multiple Response Optimization of High Temperature, Low Time Aqueous Extraction Process of Phenolic Compounds from Grape Byproducts

In this study phenolic compounds extraction from grape byproducts was conducted using pure water as a solvent. High temperatures and low time incubation periods were used in the aim of reducing the cost of the process and heightening the phenolic compounds yield. Response surface methodology (RSM) was realized to study the effect of time and temperature on crushed and uncrushed grape pomace. The phenolic content was evaluated considering the quantity (total phenolics (TPC), flavonoids (FC), total monomeric anthocyanins (TMA) and tannins (TC)), and quality (antiradical activity (AA) and antioxidant capacity (AC)) of the extracts. High temperature low time extraction design used in this study was compared to the extraction process at moderate temperatures with relatively long periods of time. This was proved to ameliorate the quantitative extraction of phenolic compounds from grape pomace without affecting their bioactivity. Moreover, multiple response optimization showed the optimal extraction parameters to be 81?C and 140 minutes for the unmilled pomace samples, and 88?C and 5 minutes for the milled. TPC, FC, TMA, TC, AA and AC are almost the same for both optimums. Thus the possibility of replacing the milling process by the extraction time prolongation (for the unmilled pomace) of 135 minutes seems to be very plausible. HPLC analysis showed different quantity and diversity of extracted phenolics for the optimums. However this difference did not significantly affect the overall activity, showing that PC in the different extracts act in complete synergy all together leading to important biological properties. The obtained results using the extraction strategy adopted in this work could lead to several industrial applications.

Effects of Compound Plant Extract on Growth Performance of Sujiang Pigs

The experiment was conducted to investigate the effects of compound plant extract on the growth performance and economic benefits of Sujiang pigs during the fattening period. A total of 50 Sujiang pigs,weighing about 60 kg( there were no significant differences in the weight of the pigs),were selected. They were randomly and evenly divided into five groups: control group,A,B,C and D groups. The pigs in the control group were fed basal diet. For the pigs in the A,B,C and D groups,per kg of basal diet was added with 100,200,300 and 400 mg of compound plant extract,respectively. The experimental duration was 44 d. The results showed that in the treatment groups,the average daily weight gains were 15. 57%,20. 68%,17. 95% and 7. 31%,respectively higher than that of the control group,the feed-gain ratios were13. 29%,16. 92%,15. 11% and 11. 48%,respectively lower than that of the control group( P > 0. 05),and the economic benefits were62. 65,83. 23,72. 50 and 42. 11 yuan,respectively higher than that of the control group. In conclusion,the addition of compound plant extract in the basal diet of Sujiang pigs during fattening period can improve the economic benefit,and the economic benefit is best when the addition amount is 200 mg/kg.

An Environment Friendly, Low-Cost Extraction Process of Phenolic Compounds from Grape Byproducts. Optimization by Multi-Response Surface Methodology

Due to their beneficial effects on human health, phenolic compounds are increasingly attracting the attention of scientists and researchers all over the world. The main interest is in the extraction process of those natural plant-originated compounds from fruits, vegetables and plant wastes, namely grape wastes, in which phenolic compounds are the most abundant secondary metabolites. This waste exploitation not only re-assimilates those byproducts into the food cycle, but also avoids major environmental problems. Herein, the optimization of the phenolic compounds concentration and free radical scavenging activity from Cabernet Sauvignon grape byproducts was conducted, using multi-response surface methodology. A conventional solid-liquid extraction process was performed with pure water as a solvent to study the effects of both time and temperature on the procedure. The maximal phenolic compounds concentration (878.9 mg/L) was reached at 47℃ after 30 hours while the optimal free radical scavenging activity (41.15%) was obtained at 30℃ after 20 hours. A multi-response surface methodology compromised between the quantity and the quality of the extracted phenolics, and the parameters maximizing both responses were obtained at 37℃ and 28 hours. This low-cost and energy saving process provides an excellent tool for further industrial applications.

Quantification of Lipid Content and Identification of the Main Lipid Classes Present in Microalgae Extracts Scenedesmus sp. for Obtaining Fatty Compounds for Biofuel Production

Microalgae biomass has been reported in the literature as one of the most promising sources for obtaining different products of industrial interest such as lipids, fatty acids, carotenoids, proteins and fibers. The lipid fraction of microalgae comprises neutral lipids, free fatty acids and polar lipids. It is of great importance to estimate the composition of the lipid fraction to define the potential for use, either as a raw material for the production of biofuels or for use for nutraceuticals and/or food purposes. The microalgae Scenedesmus sp. cultivated in a photobioreactor, the sky open raceway type, was evaluated for lipid content, identification and quantification of lipid components obtained from different extracts. In the quantification of the lipid content, extraction methods were proposed without chemical treatment (use of solvents only) such as chloroform:methanol (2:1 v/v)—Bligh & Dyer, Ethanol, Ethyl acetate:Hexane (1:1 v/v) and others with chemical treatment such as J-Schmid-Bondzynski-Ratzlaff (acid) and saponification (basic). For the identification of the main lipid components present in the extracts, the Thin layer chromatography (TLC) technique was used. This made it possible, using a simple and inexpensive method, to identify the compounds extracted by different extraction methods, that is, it was possible to verify the selectivity of the different extraction methods. In addition, it has been shown that using these methods, widely described in the literature as methods of extracting lipids in practice, extracts a wide diversity of compounds. The levels of lipids obtained via solvent extraction were up to 50% higher than those obtained with chemical treatment. In lipid extracts, obtained via solvent extraction, the presence of polar compounds, glycerides, carotenoids, pigments and sterols was identified, with up to 53% being composed of an unsaponifiable fraction, thus, presenting low selectivity for extracting fatty components. The acidic and basic treatments applied to the biomass of Scenedesmus sp. showed greater selectivity for obtaining fat components of 71.47% and 94.99%, respectively. The results showed that depending on the solvent/method used to quantify the lipids, the selectivity for obtaining the grease fraction, fundamental for conversion into biofuels, varies and the total lipid content may be overestimated.

Quantitative variation of bioactive phyto compounds in ethyl acetate and methanol extracts of Pergularia daemia(Forsk.)Chiov.

Dear Editor： Pergularia daemia Forsk （Asclepiadaceae） is a perennial twining herb commonly known as veliparuthi in Tamil. The plant has anthelmintic, laxative, antidiabetic, hepatoprotective and anti-inflammatory activities. The pharmacological properties of this plant come from bioactive phytochemicals such as alkaloids, triterpenes, saponins and flavonoids. Phytochemically, the plant has been investigated for the presence of cardenolides, alkaloids, saponins and steroidal compoundst. In the present study, we developed a rapid method for identification and quantitative determination of putative phyto compounds in the crude extracts of ethyl acetate and methanol from whole plant of Pergularia daemia.

Natural compounds and extracts from Mexican medicinal plants with anti-leishmaniasis activity: An update

Leishmaniasis is considered as an emerging, uncontrolled disease and is endemic in 98 countries. Annually, about 2 million cases of cutaneous and 500000 cases of visceraltype leishmaniasis are recorded and 60000 persons died from the disease. In Mexico,cutaneous leishmaniasis is known as chiclero's ulcer and is reported in 22 states, it is considered as a health problem. For its treatment, pentavalent antimonial drugs are administered. These drugs cause severe side effects, are costly. Drug-resistant cases have been reported and have been developing for over 70 years. One alternative to the drugs that are currently available is to find active molecules in medicinal plants. Dihydrocorynantheine, corynantheine and corynantheidine are active against Leishmania major,while harmane, pleiocarpin, buchtienin, luteolin and quercetin are active against Leishmania donovani. In Mexico, about 20 medicinal plants have been evaluated against Leishmania mexicana, among which the most active are Tridax procumbens, Lonchocarpus xuul and Pentalinon andrieuxii. From these plants, active compounds with IC_(50)≤30 mg/mL or m M have been isolated, such as 3(S)-16,17-didehydrofalcarinol or Oxylipin, cholestra-4,20,24-trien-3-one or pentalinosterol, 24-methylcholest-4-24(28)-dien-3-one, cholest-4-en-3-one, 6,7-dihydroneridie-none, neridienone, cholest-5,20,24-trien-3β-ol, and isocordoin. Today, only pentalinonsterol has been synthesized and assayed in the visceral leishmaniasis experimental model using BALB/c mice infected with Leishmania donovani. Liposome formulation of this compound administered by intravenous route at 2.5 mg/kg showed a significant reduction of parasite load in mouse liver and spleen.

Extraction of Tungsten and Molybdenum by Various Organic Compounds as Extractants

Seventy organic compounds including various organophosphorus esters, amines and oxygen-based ligands were investigated as extractants. The experiment results show that amines are excellent extractants for W and Mo. Their sequence of extraction ability for W is as follows: quarternary amine > tertiary amine > secondary amine > primary amine. Acidic organophosphorus extractants do not extract W, but can extract Mo with high extraction ability from the acidic solution. These extractants could provide a potential process for separating W from Mo.

Effect of Extractant and Temperature on Phenolic Compounds and Antioxidant Activity of Selected Spices

Ten spices marketed in Jordan, (Syzygium aromaticum L., Coriadrum sativum L., Cuminum cyminum L.,Zingiber officinale Rosc., Elettaria cardamomum, Curcuma longa, Rhus coriaria L., Cinnamomum zeylanicum Blume, Foeniculum vulgare Mill and Laurus nobilis L.) were investigated for their phenolic compounds and antioxidant activity. The influence of different extractants (methanol, ethanol and acetone) at different temperatures (20, 40 and 60°C) was examined. Results showed at 60°C using methanol, cloves had the highest level of total phenolics (781.0 mg GAE/100g using acetone). At 40°C, sumac and cloves had the highest amounts of total phenolics (343.9 mg/100g and 342 mg GAE/100g respectively). At 20°C, cloves continued to have the highest amount of total phenolics (394.7 mg/100g) using methanol as extactant. Ethanol as extractant, cloves gave the highest level of phenolics (548 mg GAE/100g, 493.4 mg GAE/100g) at 60°C, while at 20°C cloves and sumac showed the highest concentrations of phenolics (350.8 mg GAE/100g and 342.8 mg GAE/100g respectively). Acetone as extractant at 60°C, cloves had the highest levels of phenolics (781 mg GAE/100g) while at 40°C and at 20°C, sumac contributed the highest levels of total phenolics (583.2 mg GAE/100g and 754.5 mg GAE/100g). The total phenolics concentration varied significantly among the spices. Their values varied according to the extractant and extracting temperature. IC50 (radical scavenging activity) reflecting the antioxidant activity was presented. Results showed that cloves had the highest antioxidant activity while the cinnamon, turmeric and sumac had a appreciable level of antioxidant activity. Green cardamom and coriander had the lowest antioxidant activity. Antioxidant activity was positively correlated with total phenolic compounds content of the investigated spices.

Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk

Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.

Phytochemical Analysis and Antioxidant Activity of Aqueous and Hydroethanolic Extracts from Three Anticancerous Fabaceae of Northern Cameroon Pharmacopoeia

Background: Cancer continues to pose a significant threat to our society, representing one of the most pressing health concerns worldwide. This study aimed to evaluate the chemical composition and the antioxidant activity of aqueous and hydroethanolic extracts from Acacia nilotica (An), Bauhinia reticulate (Br), and Tamarindus indica (Ti) of Fabaceae family, traditionally used in Northern Cameroon for cancer treatment. Methods: The phytochemical screening of the three plants was conducted using conventional colorimetric methods, followed by the measurement of total phenol content, flavonoids, and tannins. The antiradical and antioxidant activities of both plant extracts were assessed through FRAP, ABTS, and DPPH methods. A principal components analysis was employed to correlate the quantities of the evaluated secondary metabolites with the activities. Results: Both types of extracts from the three plants contain alkaloids, saponins, flavonoids, phenolic compounds, tannins, glycosides, terpenoids, coumarins, anthocyanins, and anthraquinones. The aqueous extracts of Br and An are significantly richer (p Conclusion: The three Fabaceae plants from northern Cameroon, prepared in different solvents, can be utilized for their antiradical properties in cancer treatment.

Compound Astragalus and Salvia miltiorrhiza extract exerts anti-tumor activity by intervening the interaction of microRNA-145/microRNA-21 and Smad3C/3L phos-phorylation in hepatocellular carcinoma

OBJECTIVBE To investigate the intervention of compound Astragalus and Salvia miltiorrhiza extract(CASE) consisted of astragalosides,astragalus polysaccharides and salvianolic acids on the interaction of microRNA-145/microRNA-21(miR-145/miR-21) and Smad3 C/3 L phosphorylation(pSmad3 C/pSmad3 L) down-stream of transforming growth factor-β(TGF-β)/mitogen activated protein kinase(MAPK) signaling in hepatocellular carcinoma(HCC) progression by in vitro and in vivo experi.ments.METHODS In HepG2 cells and xenografts of nude mice,antagomir/agomir and plasmids of Smad3 C/3 L phosphorylation site mutation(Smad3 3 S-A/Smad3 EPSM) were used to intervene miR-145/miR-21 and pSmad3 C/pSmad3 L expression respectively,then incorporative CASE treatment.Cell proliferation,migration,apoptosis,tumor growth and histopathologic characteristics of xenografts,relevant proteins of TGF-β/Smad pathway and miR-145/miR-21 were evaluated.RESULTS CASE up-regulated miR-145 while down-regulated miR-21,inhibited cell proliferation,migration and tumor growth,accelerated cell apoptosis in HepG2 cells respectively transfected with Smad3 WT,Smad3 EPSM,Smad3 3 S-A plasmids in cultured dishes and xenografts of nude mice,the above effects were more evident in HepG2 cells with increased pSmad3 C.In TGF-β1-stimulated HepG2 cells and xenografts of nude mice,CASE antagonized the facilitating effects of miR-145 antagomir/miR-21 agomir on cell migration,proliferation,tumor growth and inhibiting effects of miR-145 antagomir/miR-21 agomir on cell apoptosis;CASE increased miR-145 down-regulated by miR-145 antagomir and decreased miR-21 up-regulated by miR-21 agomir,reduced protein level of pSmad3 L and their proteins including TβRⅡ,pERK1/2,pJNK1/2 and pp38 while elevated pSmad3 C expression.CONCLUSION These results suggest that pSmad3 C/pSmad3 L maybe interact with miR-145/miR-21 in HCC progression,which may be one of important molecular mechanisms of CASE's anti-HCC effects.

Molecularly Imprinted Micro-Solid-Phase Extraction for the Selective Determination of Phenolic Compounds in Environmental Water Samples with High Performance Liquid Chromatraphy

2,4,6-trichlorophenol molecularly imprinted suspension polymer has been prepared and applied to the molecularly imprinted micro-solid-phase extraction procedure for selective preconcentration of phenolic compounds from environmental water samples. The influence of functional monomer, cross-linker, polymerization condition, porogen, and the ratio of template molecule and functional monomer to cross-linker on the size of the obtained particles were investigated. It was found that methyacrylic acid as functional monomer, divinylbenzene as cross-linker, the molar ratio of template molecule and functional monomer to cross-linker was 1:4:20, the amount of AIBN was 100 mg, ultraviolet radiation at 365 nm were the optimal conditions, and at these conditions, the polymers had the best adsorption efficiency and had the monodispersity of 2 - 3 μm microsphere particles. The characteristics of the MIMSPE method were valid by high performance liquid chromatography. This MIMSPE-HPLC method has been successfully applied to the direct preconcentration and determination of phenolic compounds (phenol, 4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, pentachlorophenol) in environmental water samples.

电动拖拉机复合式振动馈能系统设计及试验

为了回收和利用电动拖拉机行驶过程中产生的振动能量,基于浮动电池组提出了一种压电-机械电磁复合式振动馈能装置;然后,根据装置的电压输出特性构建了包含整流滤波、LM317稳压、超级电容储能和Boost升压模块的电能提取电路,以满足蓄电池充电需求;最后,进行了复合式振动馈能系统的实车试验。结果表明:电动拖拉机车速为4 km/h时,馈能装置的最大输出电压为34.80 V,平均输出功率为0.57 W;经过等效计算,由复合式馈能系统回收的电能可使电动拖拉机的续航时间延长0.784 7 h。研究结果可为我国电动拖拉机的电能补给和工作时间延长提供理论与技术支撑。

宁夏枸杞酚类及其衍生物的研究与应用进展

酚类化合物是植物中重要的一类次生代谢物,具有多种生物活性,被认为是营养、功能食品的主要功效成分。宁夏枸杞(Lycium barbarum L.)作为重要的药食同源滋补品,富含酚类化合物及其衍生物。本文综述了国内外宁夏枸杞酚类化合物及其衍生物的研究进展,包括宁夏枸杞酚类化合物的提取、分离、分析与鉴定方法及生物活性;同时也总结了酚类物质对枸杞食药风味/五味的贡献、合成代谢及其深加工应用研究进展,并对枸杞酚类化合物研发存在的问题提出建议及展望。以期为宁夏枸杞酚类及其衍生物的深入研究提供参考依据,为特色资源枸杞开发利用提供理论指导。