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Physicochemical and Biochemical Characterization, Total Phenolic and Energy Value from Bulbs of Different Onion (Allium cepa L.) Varieties in Senegal
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作者 Ndeye Adiara Ndiaye Lahat Niang +1 位作者 Modou Dieng Ndeye Coumba Kane Touré 《Food and Nutrition Sciences》 CAS 2024年第2期129-139,共11页
The purpose of this study is to investigate the physicochemical properties of some local varieties of onion (Allium cepa L.) and compare them with an imported variety, all collected in May 2021. Proteins, reducing sug... The purpose of this study is to investigate the physicochemical properties of some local varieties of onion (Allium cepa L.) and compare them with an imported variety, all collected in May 2021. Proteins, reducing sugars, lipids, and polyphenol content were estimated according to the AFNOR standardized methods. The determination of calcium, magnesium, iron, sodium, potassium and phosphorus was performed by atomic absorption spectrophotometer coupled with a CCD detector. The results highlighted an average acidity of 0.377% ± 0.002% lower than the value of the imported variety which is 0.520% ± 0.001%. Local varieties have a pH ranging from 6.35 ± 0.003 to 6.42 ± 0.004, while the variety has a pH of 6.36 ± 0.003. The ash and dry matter contents vary respectively from 4.788% ± 0.004% to 8.253% ± 0.003% and 7.945% ± 0.021% to 11.945% ± 0.007% for the local varieties. Moreover, the imported one has ash and dry matter contents of 5.175% ± 0.007% and 10.035% ± 0.021% respectively. The results show that the protein, reducing sugar and lipid contents in the local onion varieties vary respectively from 2.815 ± 0.000 to 15.634 ± 0.001 g·100 g<sup>-1</sup>;4.691 ± 0.001 to 12.596 ± 0.002 g·100 g<sup>-1</sup> and 0.006 ± 0.001 to 0.050 ± 0.057 g·100 g<sup>-1</sup>. Furthermore, the imported variety has a protein, reducing sugar and lipid content of 5.649 ± 0.002;8.565 ± 0.002 g·100 g<sup>-1</sup> and 0.011 ± 0.010 g·100 g<sup>-1</sup> respectively. The maximum levels of total polyphenols are obtained in the imported variety, Bellani and Gandiol, respectively 9.973 ± 0.001, 4.535 ± 0.002, and 3.425 ± 0.006 mg EAG/g of dry matter. The local varieties have a significant calorific intake of between 35.451 ± 0.001 and 112.980 ± 0.003 kcal·100 g<sup>-1</sup> compared to the imported one with an energy value of 56.953 ± 0.001 kcal·100 g<sup>-1</sup> of dry matter. The bulbs of different onion varieties studied have a fairly high content of mineral elements. The potassium content of local varieties is between 502.16 ± 0.06 mg·100 g<sup>-1</sup> and 582.77 ± 0.04 mg·100 g<sup>-1</sup> while the imported variety has a content of 536.62 ± 1.30 mg·100 g<sup>-1</sup>. They note that the local varieties have a better calcium content (249.75 ± 0.07 to 434.20 ± 0.57 mg·100 g<sup>-1</sup>) and magnesium (142.15 ± 0.07 to 162.60 ± 0.42 mg·100 g<sup>-1</sup>) than the imported variety (229.58 ± 0.04 mg·100 g<sup>-1</sup>) except for the varieties White Grano (228.29 ± 0.01 mg·100 g<sup>-1</sup>) and Rouge Amposta (117.00 ± 0.42 mg·100 g<sup>-1</sup>) respectively. These results reveal that Gandiol, Dayo and Orient F1 are nutritionally found better due to their higher antioxidant property, proteins, carbohydrates, and reducing sugar and should be included in diets to supplement our daily allowance needed by the body. 展开更多
关键词 Allium cepa L. CHARACTERIZATION physicochemical BIOCHEMISTRY Total Phenolic
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Physicochemical Properties of the Seed Oil of Khaya senegalensis
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作者 Abimbola O. Oginni Adewale Adewuyi Rotimi A. Oderinde 《Food and Nutrition Sciences》 CAS 2024年第3期171-178,共8页
The physicochemical characteristics of Khaya senegalensis seed oil were investigated. Iodine value, saponification value, percentage free fatty acid (FFA), acid value, and peroxide value were the chemical parameters e... The physicochemical characteristics of Khaya senegalensis seed oil were investigated. Iodine value, saponification value, percentage free fatty acid (FFA), acid value, and peroxide value were the chemical parameters examined in the oil analysis, while specific gravity and refractive index were examined as physical parameters. The results showed that the acid value was 1.18 ± 0.01, the saponification value was 191.76 ± 0.01 mgKOH/gm, and the iodine value was 102.79 ± 0.01. It contained 0.59 ± 0.01 percent free fatty acid. The value of peroxide was 6.83 ± 0.01 meq/kg. The results showed that the refractive index was 1.462 ± 0.02 and the specific gravity was 0.9194 ± 0.04. The established parameters fell within the worldwide and Nigerian vegetable oil industry standards. 展开更多
关键词 Khaya senegalensis physicochemical Parameters Vegetable Oil
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Microwave irradiation-induced alterations in physicochemical properties and methane adsorption capability of coals:An experimental study using carbon molecular sieve
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作者 Xuexiang Fu Xing Tang +2 位作者 Yi Xu Xintao Zhou Dengfeng Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期165-180,共16页
In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.I... In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.In this work,the carbon molecular sieve combined with KMnO_(4)oxidation was selected to fabricate carbon molecular sieve with diverse oxidation degrees,which can serve as model substances toward coals.Afterwards,the microwave irradiation dependences of pores,functional groups,and highpressure methane adsorption characteristics of model substances were studied.The results indicated that microwave irradiation causes rearrangement of oxygen-containing functional groups,which could block the micropores with a size of 0.40-0.60 nm in carbon molecular sieve;meanwhile,naphthalene and phenanthrene generated by macro-molecular structure pyrolysis due to microwave irradiation could block the micropores with a size of 0.70-0.90 nm.These alterations in micropore structure weaken the saturated methane adsorption capacity of oxidized carbon molecular sieve by 2.91%-23.28%,suggesting that microwave irradiation could promote methane desorption.Moreover,the increased mesopores found for oxidized carbon molecular sieve after microwave irradiation could benefit CH4 diffusion.In summary,the oxidized carbon molecular sieve can act as model substances toward coals with different ranks.Additionally,microwave irradiation is a promising technology to enhance coalbed methane recovery. 展开更多
关键词 Microwave irradiation physicochemical property Coal matrix ADSORPTION Carbon molecular sieve
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Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis
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作者 Han Dang Runsheng Xu +2 位作者 Jianliang Zhang Mingyong Wang Jinhua Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile con... The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly reduced.The optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization degree.The apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and anthracite.This makes P-HC more suitable for blast furnace injection fuel.Additionally,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion. 展开更多
关键词 blast furnace injection BIOMASS cross-upgrading hydrothermal carbonization PYROLYSIS physicochemical properties gasific-ation properties
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A review:Health benefits and physicochemical characteristics of blended vegetable oils
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作者 Hina Daud Memon Sarfaraz Ahmed Mahesar +3 位作者 Sirajuddin Huseyin Kara Syed Tufail Hussain Sherazi Mohammad Younis Talpur 《Grain & Oil Science and Technology》 CAS 2024年第2期113-123,共11页
Oil blending is the method of choice used worldwide to improve oxidative stability and nutritional value.There is no such edible oil/fat that meets all the recommendations from the health point of view.The fatty acid ... Oil blending is the method of choice used worldwide to improve oxidative stability and nutritional value.There is no such edible oil/fat that meets all the recommendations from the health point of view.The fatty acid composition of vegetable oils decides the fate of the oil.Pure single oil is unable to provide a balanced amount of fatty acids(FAs)required/recommended on a daily intake basis.Blending oils/fats is an appropriate procedure of physically mixing multiple oils in suitable proportions which may provide functional lipids with improved antioxidant potential and desirable physical and chemical properties.This review piled up the accessible data on the blending of diverse oils/fats in the combination of binary,ternary,quaternary,or other types of oils into a single blended oil.Blending can be found very convincing towards appropriate FA profile,enhancement in physicochemical characteristics,and augmented stability for the period of storage or when used as cooking/frying processes which could ultimately serve as an effectual dietary intervention towards the health protectiveness. 展开更多
关键词 Vegetable oil Oil blending physicochemical properties Nutritional benefits
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Clay Materials for Ceramics Application from N’Djamena in the Chad Republic: Mineralogical, Physicochemical and Microstructural Characterization
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作者 Ndjolba Madjihingam Djoda Pagore +3 位作者 Jacques Richard Mache Bebbata Warabi Bertin Pagna Kagonbe Patrick Mountapmbeme Kouotou 《Journal of Materials Science and Chemical Engineering》 2024年第2期31-48,共18页
Herein, we report some characteristics of the clayey materials (CMs) collected from Kaliwa (C1), Kabé (C2) and Malo (C3) district in N’Djamena (Chad). Three samples were characterized applying XRF, XRD, FTIR, SE... Herein, we report some characteristics of the clayey materials (CMs) collected from Kaliwa (C1), Kabé (C2) and Malo (C3) district in N’Djamena (Chad). Three samples were characterized applying XRF, XRD, FTIR, SEM. In addition, TGA/DSC were performed to control decomposition/mass loss and show phase transitions respectively of CMs. Geochemical analysis by XRF reveals the following minerals composition: SiO<sub>2</sub> (~57% - 66%), Al<sub>2</sub>O<sub>3 </sub>(~13% - 15%), Fe<sub>2</sub>O<sub>3</sub> (~6% - 10%), TiO<sub>2</sub> (~1% - 2%) were the predominant oxides with a reduced proportion in C1, and (~7%) of fluxing agents (K<sub>2</sub>O, CaO, Na<sub>2</sub>O). Negligible and trace of MgO (~1%) and P<sub>2</sub>O<sub>5</sub> was noted. The mineralogical composition by XRD shows that, C1, C2 and C3 display close mineralogy with: Quartz (~50%), feldspar (~20%) as non-clay minerals, whereas clays minerals were mostly kaolinite (~15%), illite (~5%) and smectite (~10%). FTIR analysis exhibits almost seemingly similar absorption bands characteristic of hydroxyls elongation, OH valence vibration of Kaolinite and stretching vibration of some Metal-Oxygen bond. SEM micrographs of the samples exhibit microstructureformed by inter-aggregates particles with porous cavities. TGA/DSCconfirm the existence of quartz (570˚C to 870˚C), carbonates (600˚C - 760˚C), kaolinite (569˚C - 988˚C), illite (566˚C - 966˚C), MgO (410˚C - 720˚C) and smectite (650˚C - 900˚C). The overall characterization indicates that, these clayey soils exhibit good properties for ceramic application. 展开更多
关键词 Clay Soils Characterization MINERALOGY physicochemical Properties Ceramic Application
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Changes in Soil Physicochemical Properties under Selected Climate-Smart Agricultural Practices in Central African Republic
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作者 Julie Léancy Gougodo De Mon-Zoni Arnauld Dave Bangane Konzoba +2 位作者 Jane Akoth Omenda Mohammad Zaman Ephrem Kosh-Komba 《Open Journal of Soil Science》 2024年第1期97-114,共18页
Soil nutrient depletion as a result of continuous cultivation with insufficient external nutrient replenishment is a major challenge in sub-Saharan Africa (SSA). A trial using the organic and mineral fertilizer was es... Soil nutrient depletion as a result of continuous cultivation with insufficient external nutrient replenishment is a major challenge in sub-Saharan Africa (SSA). A trial using the organic and mineral fertilizer was established in the cassava cropping system of the Pissa and Damara areas to address the declining soil fertility. The study aimed to evaluate the effect of cow manure and mineral fertilizer in combination or sole application on soil physico-chemical properties and macronutrients. The experimental trial adopted a randomized complete block design (RCBD) replicated four times. The treatments comprised of;T1 (Control), T2 (Peasant practice), T3 (sole NPK), and T4 (Cow manure + NPK). The data on soil physicochemical analysis was subjected to a one-way analysis of variance in SAS 9.4 and the mean was separated by Tukey’s HSD test at p < 0.005. The soil pH values ranged from 4.20 to 4.91;and 4.53 to 5.28 in Pissa and Damara respectively. According to the treatments, a low pH value is observed in T3 (4.13) in the Pissa. Combined use of cow manure and the mineral fertilizer resulted in higher Mg K and N in the Pissa region and higher soil pH in Damara. The use of sole NPK (T3) gave a higher soil carbon and CN ratio. In the Pissa region the CEC, Cu, Fe, and Zn were higher in the treatments with mineral fertilizer compared to the control. Conclusively, the use of mineral fertilizer and cow manure can be used with optimum rates to improve soil physico-chemical properties on a sustainable basis. 展开更多
关键词 Cow Manure physicochemical NUTRIENTS Agroecology Nutrient Management
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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16S RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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Physicochemical properties and biological activities of polysaccharides from the peel of Dioscorea opposita Thunb.extracted by four different methods 被引量:2
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作者 Zuowei Zhao Li Wang +4 位作者 Yuan Ruan Chunnan Wen Menghuan Ge Yanyan Qian Bingji Ma 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期130-139,共10页
Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com... Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP. 展开更多
关键词 Dioscorea opposita Thunb peel POLYSACCHARIDES Different extraction methods physicochemical characteristics Biological activities
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Assessment of the Physicochemical Quality of Unrefined Shea Butter Produced in the Localities of Sarh and Koumra (Chad)
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作者 Laurent Kodji Imar Djibrine Soudy +3 位作者 Mbaiguinam Mbailao Thierry Togdjim Saddam Annour Trebo Charles Beyamra 《Food and Nutrition Sciences》 2023年第6期561-577,共17页
Introduction: The shea tree (Vitellaria paradoxa) is one of the plant species supplying Non-Timber Forest Products (NTFPs) in Chad. His edible fruits containing almonds are used as a raw material in butter processing.... Introduction: The shea tree (Vitellaria paradoxa) is one of the plant species supplying Non-Timber Forest Products (NTFPs) in Chad. His edible fruits containing almonds are used as a raw material in butter processing. This processing activity is carried out by both informal units and cooperatives. Aim: The aim of the study is to contribute to the improvement of the physicochemical quality of unrefined shea butter produced in the localities of Sarh and Koumra (Chad). Methodology: The methodology consists of conducting surveys in these units and cooperatives to identify production stages and sample butter. The samples taken were analysed for seven (7) physicochemical parameters to assess their quality. The tests are carried out in the laboratories of the Food Quality Control Center (CECOQDA). The results take into account for seven (7) physicochemical parameters that are: 1) Criteria Organoleptic: 50% black and fondant butter;50% yellow and compact butter;28.57% strong smell, 28.57% low odour, 21.43% medium odour and 21.43% rancid;2) Water Content: 0.14% ± 0.020% for yellow butter and 0.25% ± 0.040% for black (p = 0.002);3) Insoluble Impurities: 3.49% m/m ± 0.27 for yellow butter and 3.88% m/m ± 0.38 black;4) Acid Index: 5.11% ± 0.090% for yellow butter and 3.57% ± 0.130% for black;5) Iodine Index: 21.12 g I<sub>2</sub>/100 g ± 0.670 for yellow butter and 20.67 g I<sub>2</sub>/100 g ± 0.62 for black;6) Peroxide Index: 11.86 mEq/Kg ± 0.42 for yellow butter and 3.65 mEq/Kg ± 0.28 for black (p = 0.008);7) Saponification Index: 182.64 mg KOH/g ± 0.80 for yellow butter and 193.45 mg KOH/g ± 0.70 black (p = 0.037). Conclusion: This study evaluated the quality of the two varieties of unrefined shea butter. The yellow variety proves to be better in view of the results. However, efforts still have to be made on the processes to connect to the values required by the Codex Alimentarius. 展开更多
关键词 BUTTER Shea ORGANOLEPTIC physicochemical QUALITY
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Physicochemical properties and antibacterial mechanism of theabrownins prepared from different catechins catalyzed by polyphenol oxidase and peroxidase
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作者 CHEN Xiao-qiang LIU Jia-yan +4 位作者 HUANG Xue-jun WEI Yan-an SHAO Rui-xiang CHEN Ting-ting XIE Jian-chun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2905-2916,共12页
Theabrownins(TBs)are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.TBs are a class of water-soluble brown polymers with multi-molecular weight distribution pro... Theabrownins(TBs)are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.TBs are a class of water-soluble brown polymers with multi-molecular weight distribution produced by the oxidative polymerisation of tea polyphenols during the fermentation process of dark tea,both enzymatically and non-enzymatically.TBs have been extracted and purified from dark tea all the time,but the obtained TBs contain heterogeneous components such as polysaccharides and caffeine in the bound state,which are difficult to remove.The isolation and purification process was tedious and required the use of organic solvents,which made it difficult to industrialise TBs.In this study,epigallocatechin(EGC),epigallocatechin gallate(EGCG),epigallocatechin gallate(ECG),EGC/EGCG(mass ratio 1:1),EGCG/ECG(mass ratio 1:1),EGC/ECG(mass ratio 1:1)and EGC/EGCG/ECG(mass ratio 1:1:1)as substrates and catalyzed by polyphenol oxidase(PPO)and peroxidase(POD)in turn to produce TBs,named TBs-dE-1,TBs-dE-2,TBs-dE-3,TBs-dE-4,TBs-dE-5,TBs-dE-6 and TBs-dE-7.The physicochemical properties and the antibacterial activity and mechanism of TBs-dE-1–7 were investigated.Sensory and colour difference measurements showed that all seven tea browning samples showed varying degrees of brownish hue.Zeta potential in aqueous solutions at pH 3.0–9.0 indicated that TBs-dE-1–7 was negatively charged and the potential increased with increasing pH.The characteristic absorption peaks of TBs-dE-1–7 were observed at 208 and 274 nm by UV-visible(UV-vis)scanning spectroscopy.Fourier transform infrared(FT-IR)spectra indicated that they were phenolic compounds.TBs-dE-1–7 showed significant inhibition of Escherichia coli DH5α(E.coli DH5α).TBs-dE-3 showed the strongest inhibitory effect with minimum inhibitory concentration(MIC)of 1.25 mg mL–1 and MBC of 10 mg mL–1,followed by TBs-dE-5 and TBs-dE-6.These three TBs-dEs were selected to further investigate their inhibition mechanism.The TBs-dE was found to damage the extracellular membrane of E.coli DH5α,causing leakage of contents,and increase intracellular reactive oxygen content,resulting in abnormal cell metabolism due to oxidative stress.The results of the study provide a theoretical basis for the industrial preparation and product development of TBs. 展开更多
关键词 theabrownins CATECHIN enzymatic oxidation physicochemical properties antibacterial mechanism
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Effect of different process conditions on the physicochemical and antimicrobial properties of plasma-activated water
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作者 蔡志成 王佳媚 +4 位作者 王媛媛 桑晓涵 曾丽仙 邓文韬 章建浩 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第12期63-71,共9页
The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed tha... The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future. 展开更多
关键词 plasma activated water physicochemical properties treatment conditions disinfection effect
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Evaluation of Physicochemical Parameters of Biosorbents Produced from Groundnut Hull Using Microwave Assisted Irradiation Method
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作者 Augustus Newton Ebelegi Newman Tonizibeze Elijah Jackson Godwin 《Open Journal of Physical Chemistry》 CAS 2023年第1期1-12,共12页
Samples of ground nut hull were converted to biosorbents using microwave assisted method [groundnut hull treated with hydrogen peroxide (HP-GH), groundnut hull treated with distilled water (W-GH) and raw groundnut hul... Samples of ground nut hull were converted to biosorbents using microwave assisted method [groundnut hull treated with hydrogen peroxide (HP-GH), groundnut hull treated with distilled water (W-GH) and raw groundnut hull (R-GH)]. The biosorbents were further characterized using physicochemical procedures (pH dependence, bulk density, surface area, ash content, and volatile matter, moisture content). The results show that HP-GH has pH = 8.9, W-GH pH = 8.4 and R-GH pH = 8.5 which is an indication that all the biosorbents have the appropriate pH values for the uptake of cationic species within aqueous systems. Surface area analysis revealed that HP-GH has the largest surface area (74.20 m<sup>2</sup>·g<sup>-1</sup>) while W-GH and R-GH have surface area values of 29.40 m<sup>2</sup>·g<sup>-1</sup> and 21.40 m<sup>2</sup>·g<sup>-1</sup> respectively. This suggests that modification of raw groundnut hull biomass with hydrogen peroxide possibly instigated delignification of the biomass which resulted in increased surface area for HP-GH. Results from Bulk density analysis also confirm the data obtained from surface area analysis. Accordingly, R-GH displayed the highest bulk density followed by W-GH with HP-GH showing the least bulk density. The variation in pH values among the biomass used in this study may be explained by the variation in their ash content as well because pH and ash content are positively correlated. Hence, HP-GH with a pH = 8.9 has high ash content (117.31%), W-GH with pH = 8.4 has 97.93% ash content and R-GH with pH = 8.5 has 94.26% ash content. Results from moisture content analysis show that HP-GH (99.95%), W-GH (99.97%) and R-GH (99.89%) may necessitate exposure of the biosorbents to moderate heat before use. The results obtained from this study suggest that modification of ground nut hull with either distilled water or Hydrogen peroxide by means of microwave irradiation improves physicochemical properties which may perhaps increase the adsorption capacity of the biomass. 展开更多
关键词 Agrowastes Characterization physicochemical Bulk Density Surface Area Volatile Matter Groundnut Hull Hydrogen Peroxide
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Effect of Glycosylation on the Physicochemical Properties,Structure and Iron Bioavailability of Ferritin Extracted from Tegillarca granosa
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作者 SUN Bolun TAN Beibei +4 位作者 LI Gaoshang YANG Changjie ZHANG Panxue LI Chao YANG Wenge 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1068-1078,共11页
Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study wa... Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study was to determine the physicochemical properties,protein structures,and iron uptake of ferritin extracted from T.granosa,and to evaluate the potential impacts of chitosan glycosylation on these characteristics.Based on Box-Behnken design and response surface methodology,the optimal conditions for glycosylation included a ferritin/chitosan mass ratio of 4:1,a pH of 5.5,a reaction time of 10 min,and a reaction temperature of 50℃.Glycosylation caused decreased surface hydrophobicity and elevated water-holding capacity of ferritin due to the introduction of hydrophilic groups.Additionally,glycosylation improved antioxidant capacity of ferritin by 20.69%–189.66%,likely owing to the protons donated by saccharide moiety to terminate free radical chain reaction.The in vitro digestibility of ferritin was elevated by 22.56%–104.85%after glycosylation,which could be associated with lessβ-sheet content in secondary structure that made the glycosylated protein less resistant to enzymatic digestion.The results of the iron bioavailability in Caco-2 cells revealed that ferritin(78.85–231.77 ngmg^(−1))exhibited better iron bioavailability than FeSO4(51.48–114.37 ngmg^(−1))and the values were further elevated by glycosylation with chitosan(296.23–358.20 ngmg^(−1)),which may be related to the physicochemical properties of ferritin via glycosylation modification.These results provide a basis for the development of T.granosa derived ferritin and its glycosylated products,and can promote the utilization of aquatic resources. 展开更多
关键词 FERRITIN Tegillarca granosa GLYCOSYLATION box-behnken design iron bioavailability physicochemical properties
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Effects of Different Planting Years on Physicochemical Properties and Enzyme Activities in Soil of Rice-Cherry Tomato Rotation
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作者 Xiao Deng Chunyuan Wu +2 位作者 Yi Li Huadong Tan Jiancheng Su 《Open Journal of Ecology》 2023年第6期334-344,共11页
Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomat... Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomato rotation for one year (1a), three years (3a), five years (5a), seven years (7a) and ten years (10a), respectively. The major objective was to analyze the optimal rotation years of rice-cherry tomato from soil perspective, so as to provide theoretical basis for effectively avoiding continuous cropping obstacles of cherry tomato via studying the response characteristics of soil physicochemical properties, nutrient contents and enzyme activities to planting years of rice-cherry tomato rotation system. The results were as follows: 1) Soil pH value was increased year by year during 1a to 5a, reached the highest value 5.32 at 5a. However, soil acidity was sharply enhanced during 7a to 10a (P P •kg<sup>-1</sup> at 5a. 3) The content of soil available phosphorus was increased year by year with increasing of crop rotation years, and increased by 110% to 173% during 3a to 10a (P P P < 0.05). In conclusion, long-term single rotation pattern of rice-cherry tomato would aggravate soil acidification, prompt soil nutrient imbalance and reduce soil enzyme activity. 5a to 7a would be the appropriate rotation period for rice-cherry tomato, or else it would reduce soil quality, resulting in a new continuous cropping obstacle of cherry tomato. 展开更多
关键词 Rice-Cherry Tomato Rotation Planting Years SOIL physicochemical Properties Enzyme Activity
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Level of Bacteriological and Physicochemical Pollution of Surface Waters in Rural Area: The Case of Mbankomo Municipality (Center Region, Cameroon)
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作者 Vanelle Lontchi Segnou Blandine Pulchérie Tamatcho Kweyang +6 位作者 Ernest Koji Siméon Tchakonte Murielle Patricia Mabou Tokam Olive Vivien Noah Ewoti Fils Mamert Onana Ornella Eunice Wandji Kweya Antoine Tamsa Arfao 《Journal of Geoscience and Environment Protection》 2023年第3期173-188,共16页
A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). Th... A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 10<sup>5</sup> CFU/100mL;82 × 10<sup>5</sup> CFU/100mL;10 × 10<sup>5</sup> CFU/100mL;27 × 10<sup>5</sup> and 40 × 10<sup>3</sup> CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization. 展开更多
关键词 Bacteriological Quality physicochemical Parameters Surface Waters Organic Pollution Index
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A review of physicochemical and biological contaminants in drinking water and their impacts on human health
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作者 Ahsan Shah Arun Arjunan +1 位作者 Ahmad Baroutaji Julia Zakharova 《Water Science and Engineering》 EI CAS CSCD 2023年第4期333-344,共12页
Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a rev... Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a review of selected water contaminants and their impacts on human health.The World Health Organization(WHO)guidelines and regional standards for key contaminants were used to characterise water quality in the European Union and UK.The concept of safe drinking water was explained based on the non-observed adverse effect level,threshold concentrations for toxic chemicals,and their total daily intake.Various techniques for monitoring water contaminants and the drinking water standards from five different countries,including the UK,USA,Canada,Pakistan and India,were compared to WHO recommended guidelines.The literature on actual water quality in these regions and its potential health impacts was also discussed.Finally,the role of public water suppliers in identifying and monitoring drinking water contaminants in selected developed countries was presented as a potential guideline for developing countries.This review emphasised the need for a comprehensive understanding of water quality and its impacts on human health to ensure access to clean drinking water worldwide. 展开更多
关键词 Drinking water contaminants physicochemical contaminants Biological contaminants Human health risks Waterborne diseases Water quality Public health concerns Water treatment
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Investigation of Physicochemical Properties of Qalay Abdul Ali Soil,Kabul,Afghanistan
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作者 Hafizullah Rasouli Ashok Vaseashta 《Advances in Geological and Geotechnical Engineering Research》 2023年第3期55-68,共14页
The article presents the physicochemical properties of soil from six different areas in Qalay Abdul Ali,Kabul,Afghanistan.The authors collected dissimilar samples from six diverse areas,each with a unique profile iden... The article presents the physicochemical properties of soil from six different areas in Qalay Abdul Ali,Kabul,Afghanistan.The authors collected dissimilar samples from six diverse areas,each with a unique profile identifier,and transported them to the research laboratory.The key objectives of this study are to recognize and profile such areas in terms of their physical and chemical characteristics and correlate them with the earlier geological periods of the Qalay Abdul Ali Region.Due to regional conflicts in the region,such quantifications are necessary as very limited data for this region existed.From the analysis,the authors assess that the soil type is gravely soil,and silt with gravels with mostly neutral pH of the soil,although,in specific regions,it was near-acidic.The amounts of CaCO_(3),EC(electroconductivity),and pH are dissimilar according to the locations,the values of EC,and pH within a normal range at whole locations,and the remnants of plants in various quantities.These observations recommend that the soil limitations can be used accordingly for the utilization of soil factors in the regions of the study sites and extra washbasins in the country.As the population continues to grow,such data will be critical to the future sustainability of this region. 展开更多
关键词 GEOLOGY Topsoil profiles physicochemical limitations Qalay Abdul Ali Kabul Basin
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Co-influencing mechanisms of physicochemical properties of blasting dust in iron mines on its wettability 被引量:5
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作者 Jian-guo Liu Long-zhe Jin +2 位作者 Jia-ying Wang Sheng-nan Ou Tian-yang Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第9期1080-1091,共12页
This study explores the key physicochemical factors affecting the hydrophilic characteristics of iron mine blasting dust(BD). The BD is separated into an unwetted part(UWBD, hydrophobic part) and a wetted part(WBD, hy... This study explores the key physicochemical factors affecting the hydrophilic characteristics of iron mine blasting dust(BD). The BD is separated into an unwetted part(UWBD, hydrophobic part) and a wetted part(WBD, hydrophilic part). Its particle size, true density(TD), pore parameters, mineral composition, and surface compounds are comprehensively characterized and compared. The results indicate that a smaller particle size and more developed pore parameters are two key factors responsible for the strong hydrophobicity of the BD. The mineral composition of the BD has no direct effect on its wetting properties;however, it indirectly influences the deposition characteristics of the BD in water by affecting its TD. Unlike coal dust, the surface organic composition of the BD does not affect its wettability and the peak area of C–C/C–H hydrophobic groups in the C 1s X-ray photoelectron spectrum of the UWBD(45.03%) is smaller than that in the C 1s spectrum of the WBD(68.30%). Thus, eleven co-influencing processes of physicochemical properties of the BD on its wettability are summarized. This research sheds light on the key factors affecting the wettability of the BD. 展开更多
关键词 BLASTING DUST physicochemical characteristics HYDROPHILIC contact angle iron MINE
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Micromorphology and physicochemical properties of hydrophobic blasting dust in iron mines 被引量:7
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作者 Jian-guo Liu Long-zhe Jin +3 位作者 Jia-ying Wang Sheng-nan Ou Jing-zhong Guo Tian-yang Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第6期665-672,共8页
The micromorphology and physicochemical properties of hydrophobic blasting dust(HBD)from an iron mine were comprehensively analyzed by laser particle size analysis(LPSA),scanning electron microscopy(SEM),X-ray diffrac... The micromorphology and physicochemical properties of hydrophobic blasting dust(HBD)from an iron mine were comprehensively analyzed by laser particle size analysis(LPSA),scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that the HBD particles can be classified into three types based on their particle size(PS):larger particles(PS>10μm),medium particles(1μm≤PS≤10μm),and nanoparticles(PS<1μm).The cumulative volume of respirable dust(PS≤10μm)was 84.45%.In addition,three shapes of HBD were observed by SEM:prism,flake,and bulk.In particular,the small particles were mostly flaky,with a greater possibility of being inhaled.Furthermore,the body and surface chemical compounds of HBD were determined by XRD and XPS,respectively.Ammonium adipate(C6H16N2O4)was the only organic compound in the body of HBD,but its mass fraction was only 13.4%.However,the content of organic C on the surface of HBD was 85.35%.This study demonstrated that the small-particle size and large amount of organic matter on the surface of HBD are the main reasons for its hydrophobicity,which can provide important guidance for controlling respirable dust in iron mines. 展开更多
关键词 iron MINE DUST respirable DUST HYDROPHOBIC BLASTING DUST microstructure physicochemical properties particle size
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