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Ultrasound-Assisted Aqueous Enzymatic Extraction of Oil from Perilla(Perilla frutescens L.)Seeds 被引量:1
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作者 Li Yang Zhang Yan +3 位作者 Sui Xiaonan Zhang Yana Feng Hongxia Jiang Lianzhou 《大豆科技》 2019年第S01期9-14,34,共7页
In the present study the effects of ultrasonic pretreatment and the types of enzyme on oil yield were investigated.The optimum ultrasonic pretreatment parameters were found to be 250 W of ultrasonic power,30 min of ul... In the present study the effects of ultrasonic pretreatment and the types of enzyme on oil yield were investigated.The optimum ultrasonic pretreatment parameters were found to be 250 W of ultrasonic power,30 min of ultrasonic time,and 50℃of ultrasonic temperature.Five types of enzyme,Cellulase,Viscozyme L,Alcalase 2.4L,Protex 6L,and Protex 7L,were evaluated for their effectiveness in releasing oil from ultrasonic pretreated perilla seeds.The highest oil yield of 81.74%was observed in cellulase treated perilla seed samples.The physicochemical properties of the control,hexane,and enzyme extracted perilla seed oils were compared.No significant(P>0.05)differences were observed in iodine value,refractive index,unsaponifiable matter,saponification value,peroxide value,and acid value. 展开更多
关键词 perilla seed sonication enzymatic aqueous extraction fatty acids oil properties
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Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis
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作者 Jun TANG Jianguang ZENG +1 位作者 Hao LI Chenzhong JIN 《Agricultural Biotechnology》 CAS 2023年第2期91-95,104,共6页
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex... With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%. 展开更多
关键词 Pueraria edulis Total flavonoids Condensation reflux extraction method ultrasound-assisted extraction
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Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity
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作者 Xinzhu Zhang Ming Song +1 位作者 Weizhuo Xu Wei Xu 《Journal of Polyphenols》 2023年第1期35-47,共13页
The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction condit... The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products. 展开更多
关键词 Aronia melanocarpa phenolic compounds enzymatic extraction ultrasonication antibacterial effect antioxidation effect
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Extraction process of chlorogenic acid in flos lonicerae by enzymatic treatment 被引量:4
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作者 刘佳佳 赵国玲 +1 位作者 王晖 章晓骅 《Journal of Central South University of Technology》 2002年第4期246-249,共4页
A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three... A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three important factors, enzyme dosage, treatment time and treatment temperature are adapted to optimize the extraction process. The experimental results show that the extract yield of flos lonicerae and chlorogenic acid can be obviously increased by the cellulase treatment, 61.5 mg chlorogenic acid is obtained from 1.00 g flos lonicerae at most. The optimal temperature of enzymatic treatment is 40 50 ℃. Compared with the use of single cellulase, the combined treatment of cellulase and pectinase increase the extract yield obviously but fail to improve that of chlorogenic acid. 展开更多
关键词 flos lonicerae chlorogenic ACID enzymatic TREATMENT extract PROCESS
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Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds 被引量:2
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作者 JING Li-jia LI Si-yang CHANG Zui WANG Yang YAN Xiu-feng 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期239-242,共4页
Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present... Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present study,ultrasound-assisted extractions(UAE) of CPT from C.acuminata seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid Chromatography.The conditions of alkaline species and concentrations,extraction time,extraction temperature and ultrasonic power were optimized.Results show that both Na3PO4 and Na2CO3 solutions gain good extraction yields,whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does,thus aqueous Na2CO3 is more beneficial for the extraction.The optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50°C and ultrasonic power of 400 W for 60 min.Comparing with UAE with ethanol,the extraction with 0.5% Na2CO3 solution achieves higher yield.Moreover,aqueous Na2CO3 as a solvent has various advantages including non-toxicity,inflammable,non-corrosive and low cost,which ensure this UAE method is a superior method with high utilizing prospect. 展开更多
关键词 CAMPTOTHECIN Camptotheca acuminata ultrasound-assistant extraction
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Enzymatic Aqueous Extraction of Soybean Oil 被引量:1
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作者 钱俊青 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期212-216,共5页
The procedure of enzymatic aqueous extraction of soybean oil was assessed when two-step controlled enzymatic hydrolysis was applied. With aqueous extraction of soybean oil-containing protein, the highest yield of oil ... The procedure of enzymatic aqueous extraction of soybean oil was assessed when two-step controlled enzymatic hydrolysis was applied. With aqueous extraction of soybean oil-containing protein, the highest yield of oil was 96.1% at the optimized conditions studied. Soybean oil-containing protein was hydrolyzed and resulted in releasing part of oil. The separated protein that contained 40% oil was enriched due to its adsorption capacity of released oil, the average oil extraction yeild reached 93.5%. Then the high oil content protein was hydrolyzed again to release oil by enzyme, the oil extraction yeild was 80.4%. As a result, high quality of soybean oil was obtained and the content of total oil yield was 74.4%. 展开更多
关键词 水酶法 提取 大豆油 水溶液萃取 蛋白质 蛋白酶
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Extraction Hydrolysates from Larimichthys Polyactis Swim Bladder Using Enzymatic Hydrolysis
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作者 Ling Pan Yubo Tao Peng Li 《Journal of Renewable Materials》 SCIE EI 2021年第6期1099-1109,共11页
As a kind of biopolymer,hydrolysates of fish swim bladder,safer than those of land mammals,are widely used in food,cosmetics as well as pharmaceutical and biomedical fields for their biocompatibility,biodegradability,... As a kind of biopolymer,hydrolysates of fish swim bladder,safer than those of land mammals,are widely used in food,cosmetics as well as pharmaceutical and biomedical fields for their biocompatibility,biodegradability,and weak antigenicity.To enhance hydrolysate production,in this paper,the papain and alcalase hydrolysis processes of larimichthys polyactis swim bladder were optimized with orthogonal experiments.With 89.5%hydrolysate yield,the optimal processing conditions for alcalase were solid-liquid ratio of 1:30,enzyme concentration of 0.7%,and extraction time of 6 h.As for papain,under the optimal processing conditions:solid-liquid ratio of 1:20,enzyme concentration of 0.5%,and extraction time of 8 h,the hydrolysate yield was 65.1%.To obtain higher hydrolysate yields,the ultrasonic pretreatments were implemented before the optimal enzyme hydrolysis processes.With ultrasonic waves of 100 W for 50 min,the hydrolysate yields were increased 2.1%(alcalase)and 4.5%(papain),respectively.The Fourier Transform Infrared(FTIR)spectroscopic analysis revealed that the hydrolysates extracted by papain exist in triple-helical forms.The Ultra-Violet(UV)absorption spectra indicated that the aromatic amino acids in the hydrolysates had strong absorptions in the wavelength range of 240 nm–300 nm.The results of this research demonstrate that the alcalase hydrolysates have better solubility in water and the solution is more stable under ambient temperature.However,the hydrolysates extracted by papain have a gel property and are insoluble in weak acid at room temperature,which is more suitable for applications in feedstock of biomedical. 展开更多
关键词 Swim bladder enzymatic hydrolysis ultrasonic-assisted extraction hydrolysates analysis
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Analysis of anticancer compound,indole-3-carbinol,in broccoli using a new ultrasound-assisted dispersive-filter extraction method based on poly(deep eutectic solvent)-graphene oxide nanocomposite
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作者 Yanan Yuan Huanhuan Chen +2 位作者 Yehong Han Fengxia Qiao Hongyuan Yan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第2期301-307,共7页
Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challengin... Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature.In this study,a rapid,accurate,and lowcost ultrasound-assisted dispersive-filter extraction(UADFE)technique based on poly(deep eutectic solvent)-graphene oxide(PDES-GO)adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time.PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption.UADFE was developed by combining dispersive solid-phase extraction(DSPE)and filter solid-phase extraction(FSPE)to realize rapid extraction and separation.Based on the above two strategies,the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography(HPLC)allowed the rapid(15-16 min),accurate(84.3%-96.4%),and low-cost(adsorbent:3.00 mg)analysis of I3C in broccoli and was superior to solid-phase extraction,DSPE,and FSPE methods.The proposed method showed remarkable linearity(r=0.9998;range:0.0840-48.0 mg/g),low limit of quantification(0.0840 mg/g),and high precision(relative standard deviation<5.6%).Therefore,the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples. 展开更多
关键词 INDOLE-3-CARBINOL BROCCOLI Poly(deep eutectic solvent)-graphene oxide ultrasound-assisted dispersive-filter extraction Rapid analysis
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Pectinmethylesterase extraction from orange solid wastes: Optimization and comparison between conventional and ultrasound-assisted treatments
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作者 Antonio D. Rodriguez-Lopez Luis Mayor +2 位作者 María M. Galfarsoro Jorge Martinez-Otalo Esperanza M. Garcia-Castello 《Agricultural Sciences》 2013年第9期45-50,共6页
During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is thei... During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is their treatment by addition of lime and a latter pressing, obtaining a press cake and a press liquor rich in sugars (10&#176;Brix) and citric acid, protein, pectin and ethanol. For non-thermal concentration of press liquor to obtain citruss molasses (65&#176;-70&#176;Brix), the removal of pectin is necessary. Traditionally, depectinization of juices has been done by using pectinmethylesterase (PME) enzymes from external sources. In this work it performed the extraction of PME enzymes from orange peels to obtain the optimum extraction conditions. Two different methods of solventextraction were compared (conventional andultrasound-assisted methods). For the conventional extraction experiments, a central composite design with three variables ([NaCl], pH and time) and five replicates of the center point was used. For ultrasound-assisted extraction, experiments were done at pH = 5.5 and [NaCl] = 1.25M), varying extraction time (1-30 min). Response variables were PME activity, protein content and a ratio between them, named PME effectiveness (ηPME). At the same experimental conditions (pH =5.5, [NaCl] = 1.25 M, t = 15 min) it was found that conventional extractions led to slightly better results in terms of ηPME than ultrasound-assisted extraction method. 展开更多
关键词 ORANGE Peel SOLID-LIQUID extraction ultrasound-assisted extraction PECTINMETHYLESTERASE Press Liquor
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Effect of Ultrasound-Assisted Extraction of Phenolic Compounds on the Characteristics of Walnut Shells
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作者 Hannah Han Shusheng Wang +3 位作者 Milan Rakita Yanting Wang Qingyou Han Qin Xu 《Food and Nutrition Sciences》 2018年第8期1034-1045,共12页
Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially ... Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially good natural sources of antioxidants for the food and pharmaceutical industries. In this study, phenolic compounds were extracted using an ultrasonic bath, an ultrasonic probe and a standard shaking method. The extraction yield achieved with an ultrasonic probe was 51.2 mg GAE/g DW, two times higher than both the shaking method and the ultrasonic bath method which were 20.6 mg GAE/g DW and 25.8 mg GAE/g DW, respectively. Phenolic extraction was further improved by a size reduction of the walnut shells. The best extraction yield of 52.8 mg GAE/g DW was attained when the particle size was between 45 - 100 mesh. The ultrasonic probe treatment is the best method for extraction of phenolic compounds from walnut shells. Scanning electron microscopy (SEM) imaging indicated that the ultrasonic probe treatment could better rupture the hard structure of the cells, increasing the penetration of solvents and thus the extraction yield. 展开更多
关键词 WALNUT SHELL ultrasound-assisted extraction Total PHENOLIC Content (TPC) PARTICLE Size SEM Analysis
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Effect of enzymatic extraction conditions on the yield and the polymerization degree of procyanidins
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作者 Shijie Sun Xiong Chen +3 位作者 Zhaoyang Pei Lulu Xu Cuiying Qin Jing Han 《Journal of Polyphenols》 2020年第1期24-34,共11页
Grape seeds are rich sources of procyanidin(PCs)known for potential health benefi ts.In this study,PCs were extracted from defatted grape seeds by enzymatic method in which pectinase and cellulase were used.The enzyme... Grape seeds are rich sources of procyanidin(PCs)known for potential health benefi ts.In this study,PCs were extracted from defatted grape seeds by enzymatic method in which pectinase and cellulase were used.The enzyme extraction process was further optimized by single factor experiment and response surface methodology.The optimal conditions were as follows:ethanol concentration of 70%,extraction time of 70 min,extraction temperature of 35℃,liquid/solid ratio of 103:1(mL/g),pectinase/cellulase ratio of 1:1,enzyme/solid ratio of 1:314 w/w.Under the above conditions,the extraction yields and mean degree of polymerisation(mDP)of PCs reached 47.18 mg/g dry material weight and 11.2,respectively.Compared with other extraction methods,enzyme extraction can obtain PCs with higher yield and lower mDP.According to the antioxidant activity test,PCs extracts with lower mDP showed better ability to clear 1,1-Diphenyl-2-picrylhydrazyl radical(DPPH).Enzymatic extraction was an effi cient method to obtain oligomeric procyanidin which has stronger antioxidant activity. 展开更多
关键词 PROCYANIDIN grape seeds thiolysis enzymatic extraction
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Simplex - Centroid Mixture Design Applied to theAqueous Enzymatic Extraction of Fatty Acid - BalancedOil from Mixed Seeds
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作者 Li Yang Zhang Yan +2 位作者 Wang Mei Jiang Lianzhou Sui Xiaonan 《大豆科技》 2019年第S01期1-8,共8页
A one-step method was developed to extract oil from a mixture of soybeans,peanuts,linseeds,and tea seeds using an aqueous enzymatic method.The proportion of the four seeds was targeted in accordance with a fatty acid ... A one-step method was developed to extract oil from a mixture of soybeans,peanuts,linseeds,and tea seeds using an aqueous enzymatic method.The proportion of the four seeds was targeted in accordance with a fatty acid ratio of 0.27(SFA,saturated fatty acid(s))∶1(MUFA,monounsaturated fatty acid(s))∶1(PUFA,polyunsaturated fatty acid(s)),and the oil extraction yield was maximized by applying the simplex-centroid mixture design method.Three models were developed for describing the relationship between the proportion of the individual seeds in the mixture,the fatty acid ratio in the extracted oil,and the oil extraction yield,respectively.The developed models were then analyzed using an ANOVA and were found to fit the data quite well,with R2 values of 0.98,0.93,and 0.93,respectively.The three models were validated experimentally.The results indicated that the ratio of fatty acids in the oil ranged between 0.98 and 1.12(MUFA∶PUFA)and between 0.26 and 0.28(SFA∶MUFA),which were quite close to the target values of 1 and 0.27,respectively.The oil extraction yield of 62.13%was slightly higher than the predicted value(60.32%). 展开更多
关键词 Oil blend Aqueous enzymatic extraction Fatty acids Mixture design Mixed seeds
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Research on Technology Development of Traditional Chinese Medicine Extraction Based on Patent Information
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作者 Liu Yue Fu Nan +1 位作者 Shen Manzhu Yuan Hongmei 《Asian Journal of Social Pharmacy》 2023年第1期49-56,共8页
Objective To understand the development status of traditional Chinese medicine extraction technology,so as to provide a reference for enterprises and scientific research institutions to determine the direction of tech... Objective To understand the development status of traditional Chinese medicine extraction technology,so as to provide a reference for enterprises and scientific research institutions to determine the direction of technological innovation.Besides,the government can formulate scientific and technological innovation strategies.Methods Based on patent information,statistical methods were applied to analyze the development of traditional Chinese medicine extraction technology.Then,the core technology was identified by constructing a patent citation network.Finally,the main path analysis method was applied to discover the technological evolution path.Results and Conclusion The extraction technology of traditional Chinese medicine is still in the growth stage.At present,its R&D is based on enterprises,supplemented by scientific research institutions.The core technologies are ultrasonic extraction and enzymatic extraction.The main path represented by enzymatic extraction technology reveals the evolution process of traditional Chinese medicine extraction technology.Based on this,relevant suggestions are put forward.Firstly,technological innovation cooperation should be strengthened to explore new models of achievement transformation and cooperation.Secondly,key enterprises of technology clusters should be cultivated to accelerate breakthroughs in core technologies.Thirdly,combined technologies can achieve high-efficiency enzyme-assisted extraction and open up new ways of extracting traditional Chinese medicine.Fourthly,traditional techniques should be improved to develop innovative modern techniques. 展开更多
关键词 traditional Chinese medicine extraction technology technological innovation patent information technology evolution enzymatic extraction technology
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Assessment of Beauveria bassiana and Their Enzymatic Extracts against Metamasius spinolae and Cyclocephala lunulata in Laboratory
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作者 Lluvia Sánchez-Pérez Silvia Rodríguez-Navarro +3 位作者 Victor Hugo Marín-Cruz Miguel Ángel Ramos-López Alejandro Palma Ramos Juan Esteban Barranco-Florido 《Advances in Enzyme Research》 CAS 2016年第3期98-112,共15页
The application of enzymatic extracts and conidia of Beauveria bassiana in Metamasius spinolae and Cyclocephala lunulata was evaluated. The variables were mortality and time of death. In M. spinolae, mortality with ex... The application of enzymatic extracts and conidia of Beauveria bassiana in Metamasius spinolae and Cyclocephala lunulata was evaluated. The variables were mortality and time of death. In M. spinolae, mortality with extracts 29%, conidia 27% and the combination of both 31%, all had a time of death of four days. Although with different symptoms, used enzymatic extracts: contraction and softening of the joints;by conidia: mycelium in the joints;in the combination of conidia and enzymatic extracts: abundant aerial mycelium. In C. lunulata, 100% mortality in all treatments;Time of death: enzymatic extracts and extracts with conidia 1.2 days;conidia 2.8 days. Symptoms were different, enzymatic extracts: melanization and internal tissue lysis;enzymatic extract and conidia: mycelium emerged and melanization;conidia: mycelium emerged. Enzymatic extracts showed insecticidal activity in M. spinolae and C. lunulata. These results suggest the potential of enzymatic extracts as biocontrol agents to improve the use of entomopathogenic fungi. 展开更多
关键词 Insecticidal Activity Beauveria bassiana Metamasius spinolae Cyclocephala lunulata enzymatic extracts
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Alleviation of Drought Stress in Wheat Using Exogenous Ulva prolifera Extract Produced by Enzymatic Hydrolysis
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作者 Feiyu Li Siqi Zuo +5 位作者 Yongzhou Chi Chunying Du Zhaopeng Shen Xihong Han Xiaohui Wang Peng Wang 《Journal of Renewable Materials》 SCIE EI 2020年第11期1519-1529,共11页
Drought is one of the major abiotic stresses that affect plant growth and reduce agricultural productivity.Use of algal extract as a biostimulant is gaining increased attention from researchers.This study aimed to inv... Drought is one of the major abiotic stresses that affect plant growth and reduce agricultural productivity.Use of algal extract as a biostimulant is gaining increased attention from researchers.This study aimed to investigate the potential of Ulva prolifera extract(UE)as a biostimulant when enzymatically extracted under conditions of water deficit.UE treatments(0.02%,0.06%,and 0.1%)significantly improved the shoot length,root length,and dry weight of roots after 120 h of drought stress relative to that in treatment with the negative control.An increase in catalase(CAT)and peroxidase(POD)activity was also observed that resulted in improved antioxidant capacity.Application of 0.1%UE reduced the malondialdehyde(MDA)content by 30.06%compared with that in the negative control.In addition,the soluble sugar and protein content in wheat treated with 0.1%UE was increased by 23.10%and 93.51%,respectively,resulting in adjustment of the osmotic pressure.Results suggest that UE could significantly enhance the drought tolerance of wheat.This study provides a basis for increasing the value of UE as a biostimulant. 展开更多
关键词 Ulva prolifera extract enzymatic hydrolysis antioxidant capacity OSMOPROTECTANTS drought tolerance
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Extraction and Purification Process Optimization and Antioxidant Activity in vitro of Flavonoids in Amaranthus caudatus L. 被引量:3
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作者 Hongliang YAO Huihui LI 《Medicinal Plant》 CAS 2020年第4期48-53,共6页
[Objectives]To explore the optimal extraction and purification process of the flavonoids in Amaranthus caudatus L.and to study the antioxidant activity in vitro of the flavonoids in A.caudatus.[Methods]Taking A.caudat... [Objectives]To explore the optimal extraction and purification process of the flavonoids in Amaranthus caudatus L.and to study the antioxidant activity in vitro of the flavonoids in A.caudatus.[Methods]Taking A.caudatus as the raw material,flavonoids were extracted by alcohol extraction method,and AB-8 macroporous adsorption resin was selected for purification.The hydroxyl radical scavenging ability,DPPH radical scavenging ability,and O^2-radical scavenging ability were used as evaluation indicators,to explore the antioxidant activity in vitro of the flavonoids in A.caudatus.[Results]The optimal extraction process conditions of flavonoids in A.caudatus are:liquid-to-material ratio 40:1,extraction temperature 60℃,ethanol concentration 60%,ultrasonic power 320 W,extraction time 50 min.Under these conditions,the extraction yield of flavonoids in A.caudatus is(1.35±0.01)%.The optimal purification process conditions of flavonoids in A.caudatus are 2.5 g AB-8 macroporous adsorption resin,sample volume 5 mL,mass concentration of adsorption solution 1.60 mg/mL,pH value of adsorption solution 3.0,sample flow rate 3 BV/h,ethanol concentration in desorption process is 70%and the desorption flow rate is 3 BV/h.Under these conditions,the recovery rate reaches 88.35%±0.68%.[Conclusions]A.caudatus has a high content of flavonoids and has excellent free radical scavenging ability in vitro.This study is intended to provide important technical support for the research of flavonoid activity of A.caudatus and the development of functional products. 展开更多
关键词 Amaranthus caudatus L. FLAVONOIDS ultrasound-assisted extraction PURIFICATION Antioxidant activity
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Determination of Five (5) Possible Contaminants in Recycled Cardboard Packages and Food Simulants Using Ultrasound Assisted Extraction Coupled to GC-MS 被引量:3
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作者 Ioanna-Efpraxia Parigoridi Konstantoula Akrida-Demertzi Panagiotis G. Demertzis 《Materials Sciences and Applications》 2014年第10期745-751,共7页
A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphen... A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphenyl and o-terphenyl}] that can be found as residues in recycled cardboards intended for use as food packaging materials and to test for migration levels of these compounds in a food simulant (Tenax). A main objective was to develop a modified rapid and reliable method for the identification and quantification of these compounds at low concentrations. The method was based on ultrasound-assisted solvent extraction (UAE) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The developed method was applied to analyze 3 commercially available recycled carton board food-packaging materials and also to study the potential migration of the 5 organic pollutants from these materials into Tenax to check if these recycled cardboards can be considered as suitable for use in direct contact with foodstuffs. The limits of detection (LODs) of standard solutions of the 5 compounds were determined at a signal-to-noise ratio of 3. The LODs and the limits of quantification (LOQs) of examined pollutants ranged between 0.005 to 0.5 mg/kg, and 0.1 to 1 mg/kg, respectively. The extremely low amounts of most contaminants that migrate from packaging materials to Tenax indicate that the recycled cardboards tested can be safely used for direct food contact applications. 展开更多
关键词 Gas Chromatography-Mass SPECTROMETRY ultrasound-assisted SOLVENT extraction Organic POLLUTANTS Recycled CARDBOARD
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Extraction of Carotenoids and Fatty Acids from Microalgae Using Supercritical Technology 被引量:1
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作者 Lourdes Casas Cardoso Casimiro Mantell Serrano +2 位作者 Miguel Rodríguez Rodríguez Enrique J. Martínez de la Ossa Luis M. Lubián 《American Journal of Analytical Chemistry》 2012年第12期877-883,共7页
The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-as... The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-assisted extraction using N, N-dimethylformamide (DMF). The effects of extraction conditions on supercritical CO2 extraction with and within cosolvent were analyzed at different temperatures (40℃, 50℃ and 60℃) and pressures (200, 300 and 400 bars). SFE with CO2 proved to be the most selective method for the extraction of β-carotene, but under these conditions the contents of zeaxanthin and fatty acids were only comparable to or lower than those obtained with techniques that use SFE cosolvent. The SFE technique with CO2 and ethanol simultaneously extracted β-carotene and zeaxanthin and not only increased the concentrations of fatty acids obtained, but also helped to remove fatty acids (palmitoleic and linolenic acid) that were not obtained with pure CO2. Comparison of the supercritical technology with the ultrasound-assisted extraction (UAE) shows that the former technique is the most appropriate due to the fact that ethanol is generally regarded as a safe solvent in comparison to DMF. 展开更多
关键词 Carotenoids FATTY ACIDS SYNECHOCOCCUS sp. SUPERCRITICAL Technology ultrasound-assisted extraction
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Optimizing the Extraction of Anthocyanins from Pitaya(Hylocereus undatus)Pericarp 被引量:1
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作者 Shuiming CHENG Xia ZENG +1 位作者 Guoyu ZHOU Caimei YAN 《Agricultural Biotechnology》 CAS 2020年第4期168-173,共6页
[Objectives]This study was conducted to confirm the existence of anthocyanins in pitaya(Hylocereus undatus)pericarp and optimize the extraction condition.[Methods]Single-factor tests were carried out on five factors:e... [Objectives]This study was conducted to confirm the existence of anthocyanins in pitaya(Hylocereus undatus)pericarp and optimize the extraction condition.[Methods]Single-factor tests were carried out on five factors:ethanol concentration,extraction temperature,ultrasonic power,solid-to-liquid ratio and extraction time.Based on the single-factor test results,four factors and three levels of process conditions were optimized by Box-Behnken design test.[Results]Anthocyanins exist in the pericarp of pitaya,and the optimum conditions were extraction temperature 49℃,ultrasonic power 120 W,extracted time 2 h and ethanol concentration 60%.Under these conditions,the average yield of anthocyanins was 80 mg/100g.[Conclusions]This study provides a theoretical basis for the extraction of anthocyanins from the pericarp of red-flesh pitaya. 展开更多
关键词 Hylocereus undatus pericarp ANTHOCYANIN ultrasound-assisted extraction Response surface design
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Extraction of Effective Ingredient from Pomegranate Peels and Its Whitening Effect
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作者 Xinyu AO Shouqing LIU Yuhui CHEN 《Agricultural Biotechnology》 CAS 2012年第1期19-22,共4页
[ Objective] This study aimed to extract the effective ingredient of pomegranate peels and explore its whitening effect. [ Method] Pomegranate peels were used as materials for single factor experiment to determine the... [ Objective] This study aimed to extract the effective ingredient of pomegranate peels and explore its whitening effect. [ Method] Pomegranate peels were used as materials for single factor experiment to determine the optimal technique for effective ingredient extraction from pomegranate peels and explore the inhibition of the extracts on tyrosinase and whitening effect of the effective ingredient of pomegranate peels. [ Result] The optimal conditions for ultrasound-assisted extraction of effective ingredient in pomegranate peels were: liquid-to-solid ratio of 1:20 with 60% ethanol, extraction temperature of 60℃, ultrasonic intensity of 7 and pro- cessing time of 40 min, which led to relatively strong inhibition effect of pomegranate peel extracts on tyrosinase. The inhibition rate of extracts obtained with com- mon solvent reflux extraction method was only around 60%, while the inhibition rate of extracts obtained with ultrasound-assisted extraction method on tyrosinase ac- tivity had achieved around 90%, showing a very significant the difference, which indicated that during the process of extraction of effective ingredient from pome- granate peels, appropriate ultrasound-assistance was advantageous to the extraction of active ingredients; in addition, the inhibition effect of extracts on tyrosinase had increased with the increasing concentration of extracts, and the inhibition rate could achieve 100%. [ Condusion] This study provided a certain theoretical ba- sis for the utilization of pomegranate peels as natural green materials to develop whitening cosmetics. 展开更多
关键词 ultrasound-assisted extraction Common solvent reflux extraction Pomegranate peels TYROSINASE
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