Pub Date : 2023-07-24DOI: 10.21577/0103-5053.20230025
F. Sanches-Neto, N. Coutinho, V. Aquilanti, W. Silva, V. Carvalho-Silva
The efforts of contrasting the effects caused by the Covid-19 (coronavirus disease 2019) pandemic increased the disposal of active pharmaceutical ingredients. This paper reports the mechanisms and kinetics of the degradation in aqueous environments induced by OH of two drugs, among those most widely probed at the outbreak of coronavirus, nitazoxanide and hydroxychloroquine. The investigation exploits quantum chemistry techniques and a reaction rate theory combined with diffusion-controlled processes and quantum mechanical tunneling. The reaction rate constants are obtained in an environmentally relevant temperature range. The results show that (i) the deacetylation of nitazoxanide with formation of tizoxanide is kinetically the most favorable channel, in agreement with experimental work; (ii) for hydroxychloroquine, the present theoretical calculations show that the most favorable channel is the addition of OH at the aromatic ring. The half-life time degradation products are for both cases in the range between 12 to 138 days. Both drugs presented toxicities between harmful and toxic as obtained by computational toxicology calculations: The toxicity is also calculated for the degradation products: (i) in the nitazoxanide degradation process, tizoxanide was characterized as more toxic, while (ii) in the case of hydroxychloroquine, the major degradation product showed a decrease in the toxicity.
{"title":"Mechanism and Kinetics of The Degradation of Nitazoxanide and Hydroxychloroquine Drugs by Hydroxyl Radicals: Theoretical Approach to Ecotoxicity","authors":"F. Sanches-Neto, N. Coutinho, V. Aquilanti, W. Silva, V. Carvalho-Silva","doi":"10.21577/0103-5053.20230025","DOIUrl":"https://doi.org/10.21577/0103-5053.20230025","url":null,"abstract":"The efforts of contrasting the effects caused by the Covid-19 (coronavirus disease 2019) pandemic increased the disposal of active pharmaceutical ingredients. This paper reports the mechanisms and kinetics of the degradation in aqueous environments induced by OH of two drugs, among those most widely probed at the outbreak of coronavirus, nitazoxanide and hydroxychloroquine. The investigation exploits quantum chemistry techniques and a reaction rate theory combined with diffusion-controlled processes and quantum mechanical tunneling. The reaction rate constants are obtained in an environmentally relevant temperature range. The results show that (i) the deacetylation of nitazoxanide with formation of tizoxanide is kinetically the most favorable channel, in agreement with experimental work; (ii) for hydroxychloroquine, the present theoretical calculations show that the most favorable channel is the addition of OH at the aromatic ring. The half-life time degradation products are for both cases in the range between 12 to 138 days. Both drugs presented toxicities between harmful and toxic as obtained by computational toxicology calculations: The toxicity is also calculated for the degradation products: (i) in the nitazoxanide degradation process, tizoxanide was characterized as more toxic, while (ii) in the case of hydroxychloroquine, the major degradation product showed a decrease in the toxicity.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68331860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-24DOI: 10.21577/0103-5053.20230020
C. Godoy, P. Valderrama, Andreia Furtado, M. Boroski
5-Hydroxymethylfurfural (HMF) can be obtained from the dehydration of monosaccharides present in biomass, which helps add value to the raw material. The present work sought to study the relationship between the parameters of biomass characterization, including the content of reducing sugars, total soluble solids and the mid-infrared (MIR) and near-infrared (NIR) spectra, and the formation of HMF after synthesis. A thorough analysis was conducted in order to evaluate the residual agricultural biomass samples from sugarcane bagasse, corn stover, cassava branch, banana pseudostem and mango fruits after the drying (45 ºC maximum) and ball mill grinding pre-processing procedure. HMF synthesis was performed using 0.50 mol L-1 HCl and n-butanol as extracting solvent. The analytical quantification of HMF and furfural (co-product of synthesis) was performed using high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD). The highest efficiency of the synthesis of HMF was observed for the mango fruits (55.0 kg ton-1) and sugarcane bagasse biomass (47.5 kg ton-1) samples. The application of data fusion and principal component analysis (PCA) allowed us to identify the samples with greater potential for HMF synthesis.
5-羟甲基糠醛(HMF)可以从生物质中存在的单糖脱水得到，这有助于增加原料的价值。本工作旨在研究生物量表征参数，包括还原糖、总可溶性固形物含量、中红外(MIR)和近红外(NIR)光谱与合成后HMF形成之间的关系。为了对甘蔗甘蔗渣、玉米秸秆、木薯枝、香蕉假茎和芒果果实经过干燥(最高45ºC)和球磨机研磨预处理后的残留农业生物质样品进行深入分析。以0.50 mol L-1盐酸和正丁醇为提取溶剂合成HMF。采用高效液相色谱耦合二极管阵列检测器(HPLC-DAD)对糠醛和糠醛(合成副产物)进行定量分析。芒果果实(55.0 kg - t -1)和甘蔗渣(47.5 kg - t -1)样品的HMF合成效率最高。数据融合和主成分分析(PCA)的应用使我们能够识别具有更大潜力的HMF合成样品。
{"title":"Residual Lignocellulosic Biomass in the Production of HMF","authors":"C. Godoy, P. Valderrama, Andreia Furtado, M. Boroski","doi":"10.21577/0103-5053.20230020","DOIUrl":"https://doi.org/10.21577/0103-5053.20230020","url":null,"abstract":"5-Hydroxymethylfurfural (HMF) can be obtained from the dehydration of monosaccharides present in biomass, which helps add value to the raw material. The present work sought to study the relationship between the parameters of biomass characterization, including the content of reducing sugars, total soluble solids and the mid-infrared (MIR) and near-infrared (NIR) spectra, and the formation of HMF after synthesis. A thorough analysis was conducted in order to evaluate the residual agricultural biomass samples from sugarcane bagasse, corn stover, cassava branch, banana pseudostem and mango fruits after the drying (45 ºC maximum) and ball mill grinding pre-processing procedure. HMF synthesis was performed using 0.50 mol L-1 HCl and n-butanol as extracting solvent. The analytical quantification of HMF and furfural (co-product of synthesis) was performed using high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD). The highest efficiency of the synthesis of HMF was observed for the mango fruits (55.0 kg ton-1) and sugarcane bagasse biomass (47.5 kg ton-1) samples. The application of data fusion and principal component analysis (PCA) allowed us to identify the samples with greater potential for HMF synthesis.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230002
V.V.S. Machado, Lilian Fernanda Martins do Amaral, A. Sotiles, R. D. de Freitas, F. Wypych
Phenylphosphonates of zinc (Zn-PPh), calcium (Ca-PPh) and magnesium (Mg-PPh) were synthesized by the hydrothermal method. Samples showed characteristic X-ray diffraction (XRD) patterns of layered compounds with basal spacing in the range of 14-15 Å. According to Fourier transform infrared spectroscopy (FTIR), all compositions showed the presence of characteristic bands attributed to phenyl aromatic rings, phosphonate and lattice metal-oxygen (M-O) vibrations. Different concentrations of phenylphosphonate particles were applied to stabilize water-in-oil Pickering emulsions using vaseline oil in different w/o fractions. The three particle types showed greater affinity for the oil phase (wettability) and the ability to stabilize the emulsions via the Pickering effect. Ca-PPh particles contained a greater emulsified fraction after 20 days of evaluation. This result can be attributed to the particle morphology observed by scanning electron microscopy (SEM). The fibrous morphology of Ca-PPh particles is believed to increase the steric hindrance effect at the surface around the droplets, while the Zn-PPh and Mg-PPh layered particles tended to form clusters.
{"title":"Water-in-Oil Pickering Emulsions Stabilized by Divalent Metal Phenylphosphonate Particles","authors":"V.V.S. Machado, Lilian Fernanda Martins do Amaral, A. Sotiles, R. D. de Freitas, F. Wypych","doi":"10.21577/0103-5053.20230002","DOIUrl":"https://doi.org/10.21577/0103-5053.20230002","url":null,"abstract":"Phenylphosphonates of zinc (Zn-PPh), calcium (Ca-PPh) and magnesium (Mg-PPh) were synthesized by the hydrothermal method. Samples showed characteristic X-ray diffraction (XRD) patterns of layered compounds with basal spacing in the range of 14-15 Å. According to Fourier transform infrared spectroscopy (FTIR), all compositions showed the presence of characteristic bands attributed to phenyl aromatic rings, phosphonate and lattice metal-oxygen (M-O) vibrations. Different concentrations of phenylphosphonate particles were applied to stabilize water-in-oil Pickering emulsions using vaseline oil in different w/o fractions. The three particle types showed greater affinity for the oil phase (wettability) and the ability to stabilize the emulsions via the Pickering effect. Ca-PPh particles contained a greater emulsified fraction after 20 days of evaluation. This result can be attributed to the particle morphology observed by scanning electron microscopy (SEM). The fibrous morphology of Ca-PPh particles is believed to increase the steric hindrance effect at the surface around the droplets, while the Zn-PPh and Mg-PPh layered particles tended to form clusters.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68328712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230010
N. Fernandes, Lícia Luz, E. A. Alves Filho, F. A. de Aragão, G. Zocolo, B. Freitas
Melon is a pollinator-dependent crop that relies mainly on bees to set fruits. However, manselected varieties vary in their attractiveness to flower visitors, and some flower genders and melon types may be less visited than others, harming pollination. We investigated the nectar composition of male, female and hermaphrodite flowers of 270 individuals of five commercial melons Cucumis melo (Cantaloupe, Charentais, Galia, Piel de Sapo, and Yellow), and its role in flower visit by Apis mellifera foragers. We found that melon nectar is composed mainly of sugars and amino acids such as tyrosine, phenylalanine, tryptophan, and flavonoids kaempferol3-O-neohesperidoside, luteolin hexoside, and kaempferol rhamnoside. But the amount of these chemical compounds varies among the flower genders. We also developed an accurate regression model to predict the number of bee visits to melon flowers based on the nectar composition. Our results indicate that nectar composition plays little role in bee discrimination among flowers of different melon types but is essential to the honeybee choice between flower gender. The amounts of phenylalanine (49.40%) and tryptophan (12.05%) in the nectar are related to bee preference for hermaphrodite flowers. More visits to hermaphrodite flowers contribute to setting and developing well-formed fruits, increasing productivity.
甜瓜是一种依赖传粉媒介的作物，主要依靠蜜蜂来结实。然而，人工选择的品种对访花者的吸引力各不相同，某些花的性别和甜瓜类型可能比其他花的性别和甜瓜类型更少，从而损害授粉。研究了5种商品甜瓜(哈密瓜、夏兰甜瓜、加利亚甜瓜、Piel de Sapo甜瓜和黄甜瓜)270个个体的雌雄花和雌雄同体花的花蜜组成及其在蜜蜂采花过程中的作用。我们发现甜瓜花蜜主要由糖和氨基酸组成，如酪氨酸、苯丙氨酸、色氨酸和类黄酮山奈酚3- o -新橙皮苷、木犀草素己糖苷和山奈酚鼠李糖苷。但这些化合物的含量因花的性别而异。我们还建立了一个精确的回归模型来预测蜜蜂对甜瓜花的访问次数。结果表明，花蜜成分对蜜蜂对不同类型甜瓜花的识别作用不大，但对蜜蜂对花性别的选择至关重要。花蜜中苯丙氨酸(49.40%)和色氨酸(12.05%)的含量与蜜蜂对雌雄同体花的偏好有关。更多的访问雌雄同体花有助于形成和发展良好的果实，提高生产力。
{"title":"Differences in the Chemical Composition of Melon (Cucumis melo L.) Nectar Explain Flower Gender Preference by Its Pollinator, Apis mellifera","authors":"N. Fernandes, Lícia Luz, E. A. Alves Filho, F. A. de Aragão, G. Zocolo, B. Freitas","doi":"10.21577/0103-5053.20230010","DOIUrl":"https://doi.org/10.21577/0103-5053.20230010","url":null,"abstract":"Melon is a pollinator-dependent crop that relies mainly on bees to set fruits. However, manselected varieties vary in their attractiveness to flower visitors, and some flower genders and melon types may be less visited than others, harming pollination. We investigated the nectar composition of male, female and hermaphrodite flowers of 270 individuals of five commercial melons Cucumis melo (Cantaloupe, Charentais, Galia, Piel de Sapo, and Yellow), and its role in flower visit by Apis mellifera foragers. We found that melon nectar is composed mainly of sugars and amino acids such as tyrosine, phenylalanine, tryptophan, and flavonoids kaempferol3-O-neohesperidoside, luteolin hexoside, and kaempferol rhamnoside. But the amount of these chemical compounds varies among the flower genders. We also developed an accurate regression model to predict the number of bee visits to melon flowers based on the nectar composition. Our results indicate that nectar composition plays little role in bee discrimination among flowers of different melon types but is essential to the honeybee choice between flower gender. The amounts of phenylalanine (49.40%) and tryptophan (12.05%) in the nectar are related to bee preference for hermaphrodite flowers. More visits to hermaphrodite flowers contribute to setting and developing well-formed fruits, increasing productivity.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230008
Rafael L. Germscheidt, C. Morais, Danielle Francischini, M. Arruda, J. Bonacin
Metal-based catalysts are indispensable in modern chemistry and one of the biggest challenges for industrial applications is to quantify their performance and stability. The metrics of performance can be obtained in terms of the turnover number and turnover frequency, and the stability might be associated with the leaching of the heterogeneous catalysts. Thus, metal quantification is the starting point to understand and evaluate the features of catalysts. Among the technologies for metal determination, spectrophotometric analysis stands out for being cheap and easy to perform. However, the challenge is the sample preparation to direct quantification from the heterogeneous materials. Herein, it is shown how important is the photochemical pre-treatment for the quantification of the total iron from heterogeneous thin films composed of iron-based materials. The photochemical approach was used to ensure a full dissociation of iron ions before the quantification. This method was revealed to be highly effective and precise, having a wide range of applications for different iron-based catalysts.
{"title":"Photochemical Pre-Treatment to Quantify Iron in Thin Films","authors":"Rafael L. Germscheidt, C. Morais, Danielle Francischini, M. Arruda, J. Bonacin","doi":"10.21577/0103-5053.20230008","DOIUrl":"https://doi.org/10.21577/0103-5053.20230008","url":null,"abstract":"Metal-based catalysts are indispensable in modern chemistry and one of the biggest challenges for industrial applications is to quantify their performance and stability. The metrics of performance can be obtained in terms of the turnover number and turnover frequency, and the stability might be associated with the leaching of the heterogeneous catalysts. Thus, metal quantification is the starting point to understand and evaluate the features of catalysts. Among the technologies for metal determination, spectrophotometric analysis stands out for being cheap and easy to perform. However, the challenge is the sample preparation to direct quantification from the heterogeneous materials. Herein, it is shown how important is the photochemical pre-treatment for the quantification of the total iron from heterogeneous thin films composed of iron-based materials. The photochemical approach was used to ensure a full dissociation of iron ions before the quantification. This method was revealed to be highly effective and precise, having a wide range of applications for different iron-based catalysts.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230016
P. Sanches, Danilo de Oliveira, Ivan dos Reis, A. Fernandes, Alex Silva, Marcos Eberlin, P. Carvalho, Gustavo Duarte, A. Porcari
Progenesis QI (PQI) is a multiplatform bioinformatics tool that facilitates the identification workflow for metabolomics experiments. PQI uses fragmentation data provided by MassBank of North America (MoNA) libraries, among others, for metabolite annotation. However, PQI does not officially support MoNA libraries and other libraries based on structure-data files (.sdf). This paper describes the development and application of a software named MoNA to Progenesis QI Library Converter, allowing PQI and MoNA by correcting the fragmentation data of the library for Progenesis readability. We evaluated several public experimental datasets, including human plasma, plant extracts, cultured cells, bacteria, rat serum, and rat hippocampus. The results showed that it is mandatory to proceed with file conversion of each library to allow PQI to access fragmentation information from .msp (main spectra profile) files. This step is highly recommended to improve the identification level of the metabolites.
{"title":"Fitting Structure-Data Files (.SDF) Libraries to Progenesis QI Identification Searches","authors":"P. Sanches, Danilo de Oliveira, Ivan dos Reis, A. Fernandes, Alex Silva, Marcos Eberlin, P. Carvalho, Gustavo Duarte, A. Porcari","doi":"10.21577/0103-5053.20230016","DOIUrl":"https://doi.org/10.21577/0103-5053.20230016","url":null,"abstract":"Progenesis QI (PQI) is a multiplatform bioinformatics tool that facilitates the identification workflow for metabolomics experiments. PQI uses fragmentation data provided by MassBank of North America (MoNA) libraries, among others, for metabolite annotation. However, PQI does not officially support MoNA libraries and other libraries based on structure-data files (.sdf). This paper describes the development and application of a software named MoNA to Progenesis QI Library Converter, allowing PQI and MoNA by correcting the fragmentation data of the library for Progenesis readability. We evaluated several public experimental datasets, including human plasma, plant extracts, cultured cells, bacteria, rat serum, and rat hippocampus. The results showed that it is mandatory to proceed with file conversion of each library to allow PQI to access fragmentation information from .msp (main spectra profile) files. This step is highly recommended to improve the identification level of the metabolites.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230009
Anderson Figueiredo de Carvalho, Mirelly Fonseca, D. Vidal, A. Cursino, D. Firak, Fábio Lisboa
One of the greatest challenges faced by agriculture is the use of agrochemicals and the balance between food production and environmental problems associated with the excessive use of these substances. To overcome this issue, pheromones have been used to trap pests that harm crops. This work reports the use of a layered monocarboxylate, manganese laurate (MnL2), as adsorbing matrix for undecan-2-one (methyl nonyl ketone (MNK)), one of the components of the pheromone of the insect Lobiopa insularis, which is a pest in the strawberry cultivar. The manganese laurate was synthesized by a coprecipitation method and was later characterized using X-ray diffractometry, vibrational spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The characterization techniques showed that MNK was adsorbed in the manganese laurate structure in a range of 0.08 to 1.13 mg g-1, and this interaction was investigated in a factorial design experiment, in which the variables temperature, time of contact, and matrix:MNK ratio were investigated. A negative effect of increasing temperatures was observed and attributed to substrate volatilization. The adsorption was favored in increasing molar ratios and times of contact, and ideal conditions for the adsorption could be found, indicating that manganese laurate could be applied in controlledrelease tests.
{"title":"Study of Manganese Laurate as Adsorbing Matrix for Undecan-2-one: Factors Affecting Adsorption for Application in Controlled-Release of Pheromones","authors":"Anderson Figueiredo de Carvalho, Mirelly Fonseca, D. Vidal, A. Cursino, D. Firak, Fábio Lisboa","doi":"10.21577/0103-5053.20230009","DOIUrl":"https://doi.org/10.21577/0103-5053.20230009","url":null,"abstract":"One of the greatest challenges faced by agriculture is the use of agrochemicals and the balance between food production and environmental problems associated with the excessive use of these substances. To overcome this issue, pheromones have been used to trap pests that harm crops. This work reports the use of a layered monocarboxylate, manganese laurate (MnL2), as adsorbing matrix for undecan-2-one (methyl nonyl ketone (MNK)), one of the components of the pheromone of the insect Lobiopa insularis, which is a pest in the strawberry cultivar. The manganese laurate was synthesized by a coprecipitation method and was later characterized using X-ray diffractometry, vibrational spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The characterization techniques showed that MNK was adsorbed in the manganese laurate structure in a range of 0.08 to 1.13 mg g-1, and this interaction was investigated in a factorial design experiment, in which the variables temperature, time of contact, and matrix:MNK ratio were investigated. A negative effect of increasing temperatures was observed and attributed to substrate volatilization. The adsorption was favored in increasing molar ratios and times of contact, and ideal conditions for the adsorption could be found, indicating that manganese laurate could be applied in controlledrelease tests.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230017
M. Camara, Aldilene Lima, L. Jumbo, C. Tavares, C. Mendonça, O. Monteiro, Sabrina H. C. Araujo, E. D. de Oliveira, J. Neto, J. Maia, L. Costa-Júnior, C. D. da Rocha
Pectis brevipedunculata are native species and widely available in dry and semi-arid ecosystems showing high biotechnological potential. The objective of this study was to evaluate the circadian and seasonal chemical variation of the essential oil (EO) of P. brevipedunculata, as well as its acaricide effect on Rhipicephalus microplus larvae. Aerial parts were collected and submitted to the hydrodistillation process, and the chemical composition was determined by gas chromatography mass spectrometry (GC-MS). For the assays with R. microplus, the larval immersion test was performed. The main constituents were citral (75% of the EO), followed by α-pinene and limonene. In the seasonality analysis, the highest yields were in the months of April (2.08%) and August (2.05%), while in the study of circadian rhythm, the percentage was 2.0% at 6 p.m. in the rainy season, and 1.2%, dry season at 6 p.m. Concerning acaricidal activity (50% lethal concentration (LC50)), the April (1.17 mg mL-1), March (1.28 mg mL-1), June (1.37 mg mL-1), and October (1.27 mg mL-1) oils obtained were the most active and assays performed with circadian rhythm revealed in the rain season (April) at 6 p.m. and dry season (September) at 12 a.m. LC50 values of 1.75 and 1.75 mg mL-1, respectively. Additionally, this EO is selective to non-target organisms, i.e., ladybeetles and lacewing.
{"title":"Seasonal and Circadian Evaluation of the Pectis brevipedunculata Essential Oil and Its Acaricidal Activity against Rhipicephalus microplus (Acari: Ixodidae)","authors":"M. Camara, Aldilene Lima, L. Jumbo, C. Tavares, C. Mendonça, O. Monteiro, Sabrina H. C. Araujo, E. D. de Oliveira, J. Neto, J. Maia, L. Costa-Júnior, C. D. da Rocha","doi":"10.21577/0103-5053.20230017","DOIUrl":"https://doi.org/10.21577/0103-5053.20230017","url":null,"abstract":"Pectis brevipedunculata are native species and widely available in dry and semi-arid ecosystems showing high biotechnological potential. The objective of this study was to evaluate the circadian and seasonal chemical variation of the essential oil (EO) of P. brevipedunculata, as well as its acaricide effect on Rhipicephalus microplus larvae. Aerial parts were collected and submitted to the hydrodistillation process, and the chemical composition was determined by gas chromatography mass spectrometry (GC-MS). For the assays with R. microplus, the larval immersion test was performed. The main constituents were citral (75% of the EO), followed by α-pinene and limonene. In the seasonality analysis, the highest yields were in the months of April (2.08%) and August (2.05%), while in the study of circadian rhythm, the percentage was 2.0% at 6 p.m. in the rainy season, and 1.2%, dry season at 6 p.m. Concerning acaricidal activity (50% lethal concentration (LC50)), the April (1.17 mg mL-1), March (1.28 mg mL-1), June (1.37 mg mL-1), and October (1.27 mg mL-1) oils obtained were the most active and assays performed with circadian rhythm revealed in the rain season (April) at 6 p.m. and dry season (September) at 12 a.m. LC50 values of 1.75 and 1.75 mg mL-1, respectively. Additionally, this EO is selective to non-target organisms, i.e., ladybeetles and lacewing.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230007
Nicolle F. Robaina, G. Cruz, R. Cassella
In this study, we propose a microextraction method for the determination of CdII in produced waters. The process is based on the conversion of CdII ions into a hydrophobic diethyldithiocarbamate (DDTC) complex with its subsequent dispersive liquid phase microextraction (DLPME) from the aqueous medium with chloroform. The organic phase was then diluted with ethanol and Cd absorbance was measured by graphite furnace atomic absorption spectrometry (GF AAS). The experimental conditions related to the DLPME process were investigated, and the best microextraction conditions were achieved at pH = 6.0 (acetate buffer), 7.5 × 10-6 mol L-1 of DDTC, and when using 200 µL of chloroform as the extracting solvent. No dispersing solvent was needed, which allowed the recovery of approximately 140 µL of chloroform extract. Pyrolysis and atomization temperatures of the GF AAS program were determined through the construction of the respective curves. The estimated limits of detection (LOD) and quantification (LOQ) were 5 and 17 ng L-1, respectively, whereas the enrichment factor for the method was 17. Six samples of seawater and five samples of produced waters with salinities between 30 and 270‰ were analyzed as well as two certified reference materials of saline waters.
{"title":"Dispersive Liquid Phase Microextraction (DLPME) as a Strategy for CdII Separation and Determination in High-Salinity Produced Waters by Graphite Furnace Atomic Absorption Spectrometry","authors":"Nicolle F. Robaina, G. Cruz, R. Cassella","doi":"10.21577/0103-5053.20230007","DOIUrl":"https://doi.org/10.21577/0103-5053.20230007","url":null,"abstract":"In this study, we propose a microextraction method for the determination of CdII in produced waters. The process is based on the conversion of CdII ions into a hydrophobic diethyldithiocarbamate (DDTC) complex with its subsequent dispersive liquid phase microextraction (DLPME) from the aqueous medium with chloroform. The organic phase was then diluted with ethanol and Cd absorbance was measured by graphite furnace atomic absorption spectrometry (GF AAS). The experimental conditions related to the DLPME process were investigated, and the best microextraction conditions were achieved at pH = 6.0 (acetate buffer), 7.5 × 10-6 mol L-1 of DDTC, and when using 200 µL of chloroform as the extracting solvent. No dispersing solvent was needed, which allowed the recovery of approximately 140 µL of chloroform extract. Pyrolysis and atomization temperatures of the GF AAS program were determined through the construction of the respective curves. The estimated limits of detection (LOD) and quantification (LOQ) were 5 and 17 ng L-1, respectively, whereas the enrichment factor for the method was 17. Six samples of seawater and five samples of produced waters with salinities between 30 and 270‰ were analyzed as well as two certified reference materials of saline waters.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-23DOI: 10.21577/0103-5053.20230004
Pedro do Nascimento, Vilma Prado, R. D. de Jesus, Wenes Ramos da Silva, Alberto Wisniewski Jr., José Carlos Freitas de Sá Filho, A. Blank, Daniel G. de Souza, E. Wartha, P. Nogueira, V. Moraes
Research to identify plant bioactive compounds led to the evolution of extraction methods. This study optimized ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) to extract the flavonoids of Croton grewioides Baill. species contributing to characterize the polar extract profile and understand the antioxidant potential of these plant constituents. The use of experimental design and statistical treatments enabled the determination of the ideal conditions for each technique. The extracts of five accessions of C. grewioides were obtained under the optimized extraction conditions and were analyzed using ultra high-resolution mass spectrometry (FT-Orbitrap MS) operating at negative ionization mode for flavonoids detection. The accurate experimental mass obtained to the main compounds was used to attribute the molecular formula. Chemical structures of the main compounds detected were proposed using structure data bases. Chemometric analysis were performed with two FT-Orbitrap MS spectra samples using the identified metabolites and, the antioxidant activity data, showing that for this species the MAE was most effective in extracting the antioxidant compounds. It was possible to propose the structures for forty compounds in the C. grewioides extracts, demonstrating the excellent performance of the FT-Orbitrap MS in providing information on the chemical profile of polar compounds in plant extracts.
{"title":"Characterization of Flavonoids Profiles in Polar Extracts from Croton grewioides Baill. Using Ultra-High Resolution Mass Spectrometry","authors":"Pedro do Nascimento, Vilma Prado, R. D. de Jesus, Wenes Ramos da Silva, Alberto Wisniewski Jr., José Carlos Freitas de Sá Filho, A. Blank, Daniel G. de Souza, E. Wartha, P. Nogueira, V. Moraes","doi":"10.21577/0103-5053.20230004","DOIUrl":"https://doi.org/10.21577/0103-5053.20230004","url":null,"abstract":"Research to identify plant bioactive compounds led to the evolution of extraction methods. This study optimized ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) to extract the flavonoids of Croton grewioides Baill. species contributing to characterize the polar extract profile and understand the antioxidant potential of these plant constituents. The use of experimental design and statistical treatments enabled the determination of the ideal conditions for each technique. The extracts of five accessions of C. grewioides were obtained under the optimized extraction conditions and were analyzed using ultra high-resolution mass spectrometry (FT-Orbitrap MS) operating at negative ionization mode for flavonoids detection. The accurate experimental mass obtained to the main compounds was used to attribute the molecular formula. Chemical structures of the main compounds detected were proposed using structure data bases. Chemometric analysis were performed with two FT-Orbitrap MS spectra samples using the identified metabolites and, the antioxidant activity data, showing that for this species the MAE was most effective in extracting the antioxidant compounds. It was possible to propose the structures for forty compounds in the C. grewioides extracts, demonstrating the excellent performance of the FT-Orbitrap MS in providing information on the chemical profile of polar compounds in plant extracts.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68328820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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