Earthline Journal of Chemical Sciences最新文献

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Comprehensive Analysis of Nutrient Composition: Evaluating Vitamins, Essential Minerals, and Trace Metals in Neem (Azadirachta indica) Stem Bark Extract 营养成分综合分析:评估印度楝(Azadirachta indica)茎皮提取物中的维生素、必需矿物质和微量元素
Earthline Journal of Chemical Sciences Pub Date : 2024-05-11 DOI: 10.34198/ejcs.11224.283296
Ademola E. Adeoye, Akintunde M. Adeoye, Mustapha Mufliat
{"title":"Comprehensive Analysis of Nutrient Composition: Evaluating Vitamins, Essential Minerals, and Trace Metals in Neem (Azadirachta indica) Stem Bark Extract","authors":"Ademola E. Adeoye, Akintunde M. Adeoye, Mustapha Mufliat","doi":"10.34198/ejcs.11224.283296","DOIUrl":"https://doi.org/10.34198/ejcs.11224.283296","url":null,"abstract":"The current study sought to investigate the nutrients in an aqueous extract of Neem (Azadirachta indica) stem bark. The bioactive chemical contents of Neem stem bark were isolated, separated, and studied to determine the presence of vitamins, vital minerals, and trace metals. A fresh Neem sample was collected and the sample was ground into powdered form and prepared via extraction using various solvents (n-hexane, ethyl acetate, and ethanol), and the chemical constituents were separated using the GC/MS technique. The Neem stem sample was later digested with nitric acid and hydrogen peroxide in the ratio 4:1 (acid ratio). The trace metals and important minerals in digested Neem samples were determined using an atomic absorption spectrophotometer (AAS), while Na+ and K+ were determined using a flame photometer. The results revealed that calcium is the most prevalent mineral in Neem stem bark, followed by potassium and sodium, but copper, magnesium, iron, zinc, and other minerals are present in trace amounts, while cadmium and lead are virtually missing. Furthermore, according to the results of the vitamin studies, the most abundant vitamins in Neem stem bark are vitamin B3 and vitamin C, but vitamins A, B1, B6, and B12 are present in trace amounts.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140990073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Degradation of textile polyazodyes by Polyporus ciliatus laccase produced in peanut shell solid medium: purification and characterization 花生壳固体培养基中产生的纤毛多孔菌漆酶降解纺织品多氮酯:纯化和表征
Earthline Journal of Chemical Sciences Pub Date : 2024-04-14 DOI: 10.34198/ejcs.11224.249265
F. Kallel, Nadia Etiss, S. Châabouni, Mohamed Neifar
{"title":"Degradation of textile polyazodyes by Polyporus ciliatus laccase produced in peanut shell solid medium: purification and characterization","authors":"F. Kallel, Nadia Etiss, S. Châabouni, Mohamed Neifar","doi":"10.34198/ejcs.11224.249265","DOIUrl":"https://doi.org/10.34198/ejcs.11224.249265","url":null,"abstract":"This study describes decolorization of reactive sulfonated azoic dye Direct Blue 71, one of the recalcitrant and highly used industrial dyes, by Polyporus ciliatus derived laccase. Agro-industrial wastes are increasingly used as substrates for laccase production from white rot fungi through solid-state fermentation (SSF). Peanut shell (PS) is an attractive substrate for laccase production, and SSF is an adequate strategy for that purpose. It has been employed as a novel support-substrate for laccase production by Polyporus ciliatus under solid-state fermentation. The highest laccase yield of 1260 U/ml was attained using PS after 13 days of incubation at 30°C. The purified laccase (55 kDa) showed maximum activity at pH 3 and 60°C. The extracellular laccase enzyme was purified 67.6-fold to a specific activity of 1466 U/mg by a Mono-Q anion-exchange column. The purified enzyme Km value was found to be 24 µM, while the Vmax value was observed to be 0.96 µM s-1 with ABTS as a substrate. It had high thermotolerance and pH stability and was resistant to several metal ions including copper, cadmium, and iron. P. ciliatus pure laccase showed high potential for the decolorization and detoxification of the reactive sulfonated azoic dye Direct Blue 71, which suggested that this enzyme could be used for textile effluent treatment.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140705667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Some strong dimers of TNAZ - DFT treatment TNAZ 的一些强二聚体 - DFT 处理
Earthline Journal of Chemical Sciences Pub Date : 2024-03-25 DOI: 10.34198/ejcs.11224.231248
L. Türker
{"title":"Some strong dimers of TNAZ - DFT treatment","authors":"L. Türker","doi":"10.34198/ejcs.11224.231248","DOIUrl":"https://doi.org/10.34198/ejcs.11224.231248","url":null,"abstract":"TNAZ is an explosive material. Presently, some strong dimers of TNAZ have been investigated within the constraints of density functional theory at the level of B3LYP/6-31G(d,p). Core structure of the dimers of consideration is theoretically derived from pseudocyclacene structure by means of certain centric perturbations, and then nitro groups are attached at the desired positions or from two TNAZ molecules via certain intermolecular perturbations. All the present dimers are electronically stable, thermodynamically exothermic and have favorable Gibbs’ free energy of formation values at the standard states. Various structural and quantum chemical properties, including UV-VIS spectra have been obtained and discussed.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140383686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Trinitroanisole isomers - A DFT treatment 三硝基苯甲醚异构体--一种 DFT 处理方法
Earthline Journal of Chemical Sciences Pub Date : 2024-01-18 DOI: 10.34198/ejcs.11224.173187
L. Türker
{"title":"Trinitroanisole isomers - A DFT treatment","authors":"L. Türker","doi":"10.34198/ejcs.11224.173187","DOIUrl":"https://doi.org/10.34198/ejcs.11224.173187","url":null,"abstract":"Trinitroanisole isomers have been investigated within the constraints of density functional theory at the level of B3LYP/6-311++G(d,p). All the isomers are electronically stable, thermodynamically exothermic and have favorable Gibbs’ free energy of formation values at the standard states. Various quantum chemical properties, including UV-VIS spectra have been obtained and discussed. Some of the isomers considered are associated with non-Kekule alternant isoconjugate systems, therefore they might have some potential explosive character. 2,4,6-Trinitrophenylanisole is one of them and indeed it was extensively and exclusively used by Japanese as an explosive in the II world war.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139614182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Preservatives in Canned Meat and Their Potential Human Health Concerns: A Review 罐头肉中的防腐剂及其潜在的人类健康问题:综述
Earthline Journal of Chemical Sciences Pub Date : 2023-12-21 DOI: 10.34198/ejcs.11124.163172
Raed Mohammed Khalaf Al-Zaidi, Mayson Thafir Hadi, Eman J. Al-Attar, A. M. Khaleel
{"title":"Preservatives in Canned Meat and Their Potential Human Health Concerns: A Review","authors":"Raed Mohammed Khalaf Al-Zaidi, Mayson Thafir Hadi, Eman J. Al-Attar, A. M. Khaleel","doi":"10.34198/ejcs.11124.163172","DOIUrl":"https://doi.org/10.34198/ejcs.11124.163172","url":null,"abstract":"Preservatives are the most popular food enhancers for preserving food freshness and extending its shelf life. Preservatives are frequently added to processed foods, so they are crucial to ensuring that the food remains fresh for a longer period of time. Several types of food preservatives are available currently some are manufactured while others occur naturally. Meat is one of the most important types of food that is disposed to chemical or enzymatic damage, especially after its manufacture as a result of the breakdown of fats, proteins and carbohydrates, which in turn causes the emergence of undesirable and unhealthy changes in smell, flavor and texture, making it unsuitable for human consumption. Among the substances allowed to be used as preservatives for canned meat are sodium acetates, nitrites, nitrates, sorbates, and sulphites. The current review aims to summarize the most important preservatives used in canned meat and indicate their potential negative impact human health.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138951116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the Interaction of Noscapine (Narcotine) with Ammonium Tellurate in Sulphuric Acid 关于那可丁(烟碱)与碲酸铵在硫酸中的相互作用
Earthline Journal of Chemical Sciences Pub Date : 2023-12-18 DOI: 10.34198/ejcs.11124.141146
F. Sánchez-Viesca, Reina Gómez
{"title":"On the Interaction of Noscapine (Narcotine) with Ammonium Tellurate in Sulphuric Acid","authors":"F. Sánchez-Viesca, Reina Gómez","doi":"10.34198/ejcs.11124.141146","DOIUrl":"https://doi.org/10.34198/ejcs.11124.141146","url":null,"abstract":"The purpose of this study is to clear up what is happening in the test tube during the interaction of ammonium tellurate with noscapine in sulphuric acid (Brociner test). The approach is a Theoretical Organic Chemistry Study based on the chemical deportment of reagent and substrate, the reaction medium, and experimental conditions. This point out that a redox process is going up, with the following results: meta-telluric acid is formed in situ whose protonation yields the reactive species. Reaction with the methylenedioxy group present in noscapine affords an oxonium salt. Reaction proceeds when a water molecule forms a hemiacetal and an organometallic ester, a tellurate. Acidolysis of the latter gives rise to a concerted mechanism involving five electron-shifts. This way the following compounds are formed: tellurious acid, an ortho-benzoquinone, and formaldehyde. Tellurium dioxide results by acid catalyzed dehydration of tellurious acid.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139173493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Perturbations on Oxybiotin Leading to Biotin. A DFT Treatment 对导致生物素的氧基生物素的扰动。DFT 处理
Earthline Journal of Chemical Sciences Pub Date : 2023-12-18 DOI: 10.34198/ejcs.11124.147161
L. Türker
{"title":"Perturbations on Oxybiotin Leading to Biotin. A DFT Treatment","authors":"L. Türker","doi":"10.34198/ejcs.11124.147161","DOIUrl":"https://doi.org/10.34198/ejcs.11124.147161","url":null,"abstract":"In the present computational study, conversion of oxybiotin to biotin by means of oxygen to sulfur replacement has been investigated within the restrictions of density functional theory at the level of B3LYP/6-31++G(d,p). Both of the molecules have not only exothermic heat of formations but also favorable Gibbs free energy of formation values at the standard state. They are electronically stable. Various quantum chemical data accompanying the perturbation considered have been collected and discussed including UV-VIS spectra. The oxygen to sulfur replacement highly affects not only the distribution of molecular orbital energy levels but also the energies of the molecular orbitals in such a way that going from oxybiotin to biotin the HOMO energy level raises up but the LUMO decreases. The both occur at unequal extents thus biotin exhibits some bathochromic effect compared to oxybiotin.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Tautomers of 2,4-dihydro-3H-1,2,4-triazol-3-one and their Composites with NTO - A DFT Treatment 2,4-二氢-3H-1,2,4-三唑-3-酮的同系物及其与 NTO 的复合材料 - DFT 处理
Earthline Journal of Chemical Sciences Pub Date : 2023-12-10 DOI: 10.34198/ejcs.11124.121140
L. Türker
{"title":"Tautomers of 2,4-dihydro-3H-1,2,4-triazol-3-one and their Composites with NTO - A DFT Treatment","authors":"L. Türker","doi":"10.34198/ejcs.11124.121140","DOIUrl":"https://doi.org/10.34198/ejcs.11124.121140","url":null,"abstract":"In the present density functional study, some tautomers of 2,4-dihydro-3H-1,2,4-triazol-3-one (1,2-dihydro-1,2,4-triazol-3-one) and their composites formed with NTO have been considered within the constraints of the density functional theory and the basis set employed (B3LYP/6-311++G(d,p)). The triazolone considered is the precursor of NTO in various methods. It may exhibit 1,3-proton tautomerism. Various energies, QASR, quantum chemical and spectral properties have been harvested and discussed. All the considered species have exothermic heat of formation and favorable Gibbs free energy of formation values at the standard states and they are stable electronically. Although most of the composites considered exhibit a directed interaction between their partners, one of them possesses perpendicular (T-type) orientation. Certain hydrogen bondings between the tautomers and NTO occur at different extents, depending on the particular tautomer involved in the composite. Both of the components have hydrogen bond donor and acceptor properties except composite NTO+T2, in which the tautomer is the hydrogen bond donor and NTO is the acceptor. The tautomers absorb in the UV region of the spectrum like NTO, whereas in all the composites appreciable changes in the appearance of the spectra happen and certain degree of bathochromic effect occurs as compared to the respective spectra of the partners.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138982563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Biogas Production from Plantain and Yam Peels: Modelling using Response Surface Methodology 利用车前草和山药皮生产沼气:利用响应面方法建模
Earthline Journal of Chemical Sciences Pub Date : 2023-12-08 DOI: 10.34198/ejcs.11124.105119
Koffi Kan Raymond Kouame, Abollé Abollé, A. Kouakou, K. Gbangbo, A. Ehouman, Benjamin Yao
{"title":"Biogas Production from Plantain and Yam Peels: Modelling using Response Surface Methodology","authors":"Koffi Kan Raymond Kouame, Abollé Abollé, A. Kouakou, K. Gbangbo, A. Ehouman, Benjamin Yao","doi":"10.34198/ejcs.11124.105119","DOIUrl":"https://doi.org/10.34198/ejcs.11124.105119","url":null,"abstract":"The world’s growing demand for energy and our concern to preserve the environment have prompted research into alternative sources of energy. Renewable energy from biomass is one such opportunity. The aim of this study is to model the production of biogas from the anaerobic digestion of plantain and yam peelings and cattle dung. A characterisation of these residues showed their good suitability for methanisation with good moisture contents (˃70%), high volatile solids contents (˃75%) and C/N ratios of between 20 and 30. In addition, methanisation trials under mesophilic conditions following a mixing plan generated quantities of biogas ranging from 128 to 565 mL with CH4 contents of between 54.03 and 72.98%. The digester made up of 1/6 plantain peels + 2/3 yam peels + 1/6 cattle dung gave the best biogas yield with 565 mL for 67.52% CH4. The model established from these results is highly significant with an F value (1268.01) having a probability significantly lower than 0.05. In addition to the coefficients R2 (0.9994) and R2 (0.9986) which adjust are very close to unity, there is a good correlation between the experimental results and those predicted. This prediction model is therefore reliable for explaining biogas production. However, further study of the kinetics of anaerobic digestion and biogas treatment remains important.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138589898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Ladder-like Organostannoxane: Synthesis and Crystal Structure of the Second Polymorph {[(C6H5)2Sn]2[(C6H5)2ClSn]2(μ3-O)2(μ2-OH)2}∙[DMF]2 梯状有机锡氧烷:第二种多晶体{[(C6H5)2Sn]2[(C6H5)2ClSn]2(μ3-O)2(μ2-OH)2}∙[DMF]2的合成与晶体结构
Earthline Journal of Chemical Sciences Pub Date : 2023-11-21 DOI: 10.34198/ejcs.11124.083103
M. Sarr, M. Diop, Mouhamadou Sembéne Boye, Aminata Diasse-Sarr, L. Diop,, Allen G. Oliver
{"title":"Ladder-like Organostannoxane: Synthesis and Crystal Structure of the Second Polymorph {[(C6H5)2Sn]2[(C6H5)2ClSn]2(μ3-O)2(μ2-OH)2}∙[DMF]2","authors":"M. Sarr, M. Diop, Mouhamadou Sembéne Boye, Aminata Diasse-Sarr, L. Diop,, Allen G. Oliver","doi":"10.34198/ejcs.11124.083103","DOIUrl":"https://doi.org/10.34198/ejcs.11124.083103","url":null,"abstract":"A ladder-like organostannoxane identified as a polymorph of bis-[chloro-(m2-hydroxo)-(m3-oxo)-tetraphenyl-di-tin] dimethylformamide solvate, {[(C6H5)2Sn]2[(C6H5)2ClSn]2(μ3-O)2(μ2-OH)2}[DMF]2 (1), has been synthesized and structurally characterized by means of single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the monoclinic space group P21/c with a = 23.4137(12) Å, b = 11.2525(6) Å, c = 20.2719(11) Å, β = 100.461(2)°, V = 5252.1(5) Å3, Z = 4 and Z’ = 1. The XRD discloses that the polymorph reported in this work is the full molecule which does not crystallize about any inversion center. Complex 1 exhibits a tetranuclear organotin(IV) ladder-like structure containing two external chlorides. The tetranuclear structure is comprised of a three-rung-staircase Sn4O4 cluster which consists of a ladder of four Sn2O2 units. The central Sn2O2 core forms dihedral angles of 4.00(7)° and 1.62(8)° with its two fused four-membered rings, describing a slightly bent ladder. This folding is further noticed with the dihedral angle between the two external Sn2O2 cores of 4.65(8)°. In the structure, two types of distorted trigonal bipyramid geometry at tin centers like-arrangement are disclosed. The most Sn–O bridges bond lengths describe a static trans effect affording dissymmetrical bonds. The dimethylformamide solvate molecules form a dihedral angle of 74.5(2)° and are interlinked to the tetranuclear organotin(IV) ladder via O–H···O hydrogen bond patterns. Additional inner C–H···Cl and C–H···O hydrogen bonds as well the C–H···O interactions are present. Moreover, the intermolecular C–H···O hydrogen bonds do not contribute to direct the crystal structure framework; they do not play an important function in forming a supramolecular architecture.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139253570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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