Lundoi Tobias Lee, Ana Paula Martinazzo, Sabrinna Aires Garcia, Pedro Amorim Berbet, C. Teodoro
Fungi are one of the main food spoilage agents. Numerous species when subjected to stress conditions produce secondary metabolites known as mycotoxins, which are mutagenic and carcinogenic substances. The fungus Aspergillus flavus is one of the main contaminants of grains and is known to produce Aflatoxin. Pesticides are used in agriculture to contain fungi and other pests, but they harm other species, the environment and the human health, in addition to the development of resistance to these substances in pest species. Natural alternatives have been sought to control these organisms. In this context, essential oils are a viable option against A. flavus. The aim of this study was to identify the main components and evaluate the effectiveness of lemongrass essential oil (Cymbopogon flexuosus) for controlling the fungus Aspergillus flavus. Initially, the effect of essential oil on mycelial growth of the fungus was assessed by in vitro tests at the doses: 0.05; 0.1; 0.2; 0.4; 0.6; 0.8; 1.6; 3.2; 6.4; and 12.8 μL mL-1. The minimum inhibitory concentration (MIC) was 0.8 μL mL-1. The in vivo test was performed at the following concentrations: 0.6; 0.8; and 1.6 μL mL-1. The results showed that the essential oil has fungicidal potential against A. flavus. The main component of the essential oil was citral.
{"title":"Control of Aspergillus flavus in wheat grains using Cymbopogon flexuosus essential oil","authors":"Lundoi Tobias Lee, Ana Paula Martinazzo, Sabrinna Aires Garcia, Pedro Amorim Berbet, C. Teodoro","doi":"10.22571/2526-4338528","DOIUrl":"https://doi.org/10.22571/2526-4338528","url":null,"abstract":"Fungi are one of the main food spoilage agents. Numerous species when subjected to stress conditions produce secondary metabolites known as mycotoxins, which are mutagenic and carcinogenic substances. The fungus Aspergillus flavus is one of the main contaminants of grains and is known to produce Aflatoxin. Pesticides are used in agriculture to contain fungi and other pests, but they harm other species, the environment and the human health, in addition to the development of resistance to these substances in pest species. Natural alternatives have been sought to control these organisms. In this context, essential oils are a viable option against A. flavus. The aim of this study was to identify the main components and evaluate the effectiveness of lemongrass essential oil (Cymbopogon flexuosus) for controlling the fungus Aspergillus flavus. Initially, the effect of essential oil on mycelial growth of the fungus was assessed by in vitro tests at the doses: 0.05; 0.1; 0.2; 0.4; 0.6; 0.8; 1.6; 3.2; 6.4; and 12.8 μL mL-1. The minimum inhibitory concentration (MIC) was 0.8 μL mL-1. The in vivo test was performed at the following concentrations: 0.6; 0.8; and 1.6 μL mL-1. The results showed that the essential oil has fungicidal potential against A. flavus. The main component of the essential oil was citral.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43910580","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}
Os micronutrientes, micro ou oligoelementos, incluem vitaminas e alguns metais, sendo que uma parcela significativa da população mundial apresenta deficiência nutricional desses elementos. Este estudo avaliou os teores de micronutrientes metálicos em Crassostrea rhizophorae (ostra) e Mytella guyanensis (sururu) coletados no sul da Bahia, Brasil, num trecho de 280 km de extensão. Os teores dos metais (Cu, Fe, Mn e Zn) da parte edível das espécies foram avaliados em espectrometria de emissão óptica de plasma indutivamente acoplado (ICP OES). As concentrações médias encontradas para C. rhizophorae e M. guyanensis, respectivamente, foram: Cu (2,09 ± 0,90 e 2,31 ± 0,63); Fe (32,03 ± 4,18 e 213,36 ± 51,67); Mn (1,75 ± 0,44 e 13,61 ± 2,83) e Zn (129,54 ± 25,88 e 12,13 ± 1,13), em mg kg-1. Ambos os bivalves foram relevantes na concentração dos micronutrientes investigados, com destaque para os valores elevados de Zn em C. rhizophorae e de Fe em M. guyanensis. Palavras-chave: Cobre, elementos essenciais, ferro, manganês, zinco.
{"title":"Micronutrientes metálicos nos moluscos bivalves Crassostrea rhizophorae e Mytella guyanensis","authors":"Glaucia Batista Maciel dos Santos, Guisla Boehs","doi":"10.22571/2526-4338536","DOIUrl":"https://doi.org/10.22571/2526-4338536","url":null,"abstract":"Os micronutrientes, micro ou oligoelementos, incluem vitaminas e alguns metais, sendo que uma parcela significativa da população mundial apresenta deficiência nutricional desses elementos. Este estudo avaliou os teores de micronutrientes metálicos em Crassostrea rhizophorae (ostra) e Mytella guyanensis (sururu) coletados no sul da Bahia, Brasil, num trecho de 280 km de extensão. Os teores dos metais (Cu, Fe, Mn e Zn) da parte edível das espécies foram avaliados em espectrometria de emissão óptica de plasma indutivamente acoplado (ICP OES). As concentrações médias encontradas para C. rhizophorae e M. guyanensis, respectivamente, foram: Cu (2,09 ± 0,90 e 2,31 ± 0,63); Fe (32,03 ± 4,18 e 213,36 ± 51,67); Mn (1,75 ± 0,44 e 13,61 ± 2,83) e Zn (129,54 ± 25,88 e 12,13 ± 1,13), em mg kg-1. Ambos os bivalves foram relevantes na concentração dos micronutrientes investigados, com destaque para os valores elevados de Zn em C. rhizophorae e de Fe em M. guyanensis. \u0000Palavras-chave: Cobre, elementos essenciais, ferro, manganês, zinco.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44666677","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}
Ana Rosa de Figueiredo, Leirson Rodrigues da Silva, S. Camargo, L. S. Morais
Lavandula dentata L., popularly known as lavender, is considered to be a medicinal plant that has great economic potential. The aims of the present study were to characterize the morphology of L. dentata grown in Paraíba do Sul, Rio de Janeiro, Brazil and determine the content and chemical composition of its essential oil. Morphology of the plant was determined using the optical microscope, digital calliper and measuring tape. The fresh plant material characteristics consisting of the branches, leaves, and inflorescence were described. The essential oil was obtained by hydrodistillation and analyses chemical characteristics were performed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC/MS). Our study shows a large number of non-glandular trichomes were identified, as well as two types of glandular trichomes, including capitate and peltate glandular trichomes. This work achieved high essential oil content which were related to vegetable biomass. The major constituents found in the essential oil from L. dentata were the monoterpenes: eucalyptol - 1.8 cineol (39.43%), camphor (20.11%), and fenchone (18.40%). Thus, it was possible to characterize the morphology and chemical composition of L. dentata.
Lavandula dentata L.，俗称薰衣草，被认为是一种具有巨大经济潜力的药用植物。本研究的目的是表征生长在巴西里约热内卢Paraíba do Sul，里约热内卢de Janeiro的L. dentata的形态，并确定其精油的含量和化学成分。利用光学显微镜、数字卡尺和卷尺测定了植株的形态。描述了由枝条、叶片和花序组成的新鲜植物材料特征。采用水蒸气蒸馏法提取精油，并采用气相色谱(GC)和气相色谱-质谱联用(GC/MS)对其化学特性进行分析。我们的研究发现了大量的非腺毛，以及两种类型的腺毛，包括头状和盆状腺毛。本研究获得了与植物生物量有关的高精油含量。主要成分为单萜类:桉叶精油(39.43%)、樟脑(20.11%)和茴香(18.40%)。因此，有可能表征齿形草的形态和化学成分。
{"title":"Morphological and phytochemical characterization of Lavandula dentata L. cultivated in Paraíba do Sul, Rio de Janeiro, Brazil","authors":"Ana Rosa de Figueiredo, Leirson Rodrigues da Silva, S. Camargo, L. S. Morais","doi":"10.22571/2526-4338483","DOIUrl":"https://doi.org/10.22571/2526-4338483","url":null,"abstract":"Lavandula dentata L., popularly known as lavender, is considered to be a medicinal plant that has great economic potential. The aims of the present study were to characterize the morphology of L. dentata grown in Paraíba do Sul, Rio de Janeiro, Brazil and determine the content and chemical composition of its essential oil. Morphology of the plant was determined using the optical microscope, digital calliper and measuring tape. The fresh plant material characteristics consisting of the branches, leaves, and inflorescence were described. The essential oil was obtained by hydrodistillation and analyses chemical characteristics were performed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC/MS). Our study shows a large number of non-glandular trichomes were identified, as well as two types of glandular trichomes, including capitate and peltate glandular trichomes. This work achieved high essential oil content which were related to vegetable biomass. The major constituents found in the essential oil from L. dentata were the monoterpenes: eucalyptol - 1.8 cineol (39.43%), camphor (20.11%), and fenchone (18.40%). Thus, it was possible to characterize the morphology and chemical composition of L. dentata.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41699700","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}
In this study, honeybees, propolis, air, soil and plant samples were gathered from two contrasting sites Ħal Luqa (industrial area) and L-Imġarr (agricultural area) in mainland Malta. Superficial heavy metals were extracted from the samples and tested using microwave plasma-atomic emission spectrometry in order to determine the concentrations of Ag, As, Cd, Cr, Cu, Pb, Sn, Zn, Ni and Hg. The honeybee and propolis samples were digested using nitric acid and hydrogen peroxide and then ashed using a muffle furnace in order to prepare mineral solutions. Simultaneously the air samplers, soil and plant samples were washed using de-ionised water in order to extract the heavy metals settling on sample surfaces. Different methods of filtration were used in order to extract the metals from the surfaces of the samples. The most abundant metals in honeybees and propolis, and on plant and soil samples, were Sn and As (p<0.0001). In air samples0, the most abundant metal was Pb followed by Sn (p<0.05). These findings indicate that the honeybee and its propolis are good indicators for Sn and As contamination.
{"title":"Honeybees and their products as bioindicators for heavy metal pollution in Malta","authors":"D. Borg, E. Attard","doi":"10.22571/2526-4338282","DOIUrl":"https://doi.org/10.22571/2526-4338282","url":null,"abstract":"In this study, honeybees, propolis, air, soil and plant samples were gathered from two contrasting sites Ħal Luqa (industrial area) and L-Imġarr (agricultural area) in mainland Malta. Superficial heavy metals were extracted from the samples and tested using microwave plasma-atomic emission spectrometry in order to determine the concentrations of Ag, As, Cd, Cr, Cu, Pb, Sn, Zn, Ni and Hg. The honeybee and propolis samples were digested using nitric acid and hydrogen peroxide and then ashed using a muffle furnace in order to prepare mineral solutions. Simultaneously the air samplers, soil and plant samples were washed using de-ionised water in order to extract the heavy metals settling on sample surfaces. Different methods of filtration were used in order to extract the metals from the surfaces of the samples. The most abundant metals in honeybees and propolis, and on plant and soil samples, were Sn and As (p<0.0001). In air samples0, the most abundant metal was Pb followed by Sn (p<0.05). These findings indicate that the honeybee and its propolis are good indicators for Sn and As contamination.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2020-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48253563","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}
S. Costa, I. J. N. Brito, L. Lohmann, J. I. M. D. Melo
This study reports eight new records of the tribe Bignonieae (Bignoniaceae) for Paraiba state, northeastern Brazil: Anemopaegma album (Mart. ex DC.), Anemopaegma gracile Bureau & K.Schum., Bignonia corymbosa (Vent.) L.G. Lohmann, Bignonia ramentacea (Mart. ex DC.) L.G. Lohmann, Bignonia sciuripabulum (K. Schum.) L.G. Lohmann, Cuspidaria argentea (Wawra) Sandwith, Cuspidaria lateriflora (Mart.) DC., and Fridericia conjugata (Vell.) L.G. Lohmann. These species were found in the Caatinga and/or the Atlantic Forest, growing on sandy and clay soils of dry and humid forests, from lowlands to high altitudes. For each new occurrence for the state of Paraiba, we present detailed description, taxonomic notes, and information on phenology, geographic distribution, illustrations and photographs.
{"title":"New records of the tribe Bignonieae (Bignoniaceae) for Paraiba state, northeastern Brazil","authors":"S. Costa, I. J. N. Brito, L. Lohmann, J. I. M. D. Melo","doi":"10.22571/2526-4338251","DOIUrl":"https://doi.org/10.22571/2526-4338251","url":null,"abstract":"This study reports eight new records of the tribe Bignonieae (Bignoniaceae) for Paraiba state, northeastern Brazil: Anemopaegma album (Mart. ex DC.), Anemopaegma gracile Bureau & K.Schum., Bignonia corymbosa (Vent.) L.G. Lohmann, Bignonia ramentacea (Mart. ex DC.) L.G. Lohmann, Bignonia sciuripabulum (K. Schum.) L.G. Lohmann, Cuspidaria argentea (Wawra) Sandwith, Cuspidaria lateriflora (Mart.) DC., and Fridericia conjugata (Vell.) L.G. Lohmann. These species were found in the Caatinga and/or the Atlantic Forest, growing on sandy and clay soils of dry and humid forests, from lowlands to high altitudes. For each new occurrence for the state of Paraiba, we present detailed description, taxonomic notes, and information on phenology, geographic distribution, illustrations and photographs.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41419479","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}
Joice Machado Garcia, Alessandra Leite da Silva, Catarina Araújo Siqueira, R. Longo
Green areas, whether located in urban or rural environments, play an important role in maintaining ecological systems that provide vital environmental services for the quality of life of populations. In this sense, the present study assessed the environmental damage in the forest remnants that make up the Santa Genebrinha ecological corridor in Campinas city, São Paulo State, to identify limitations in the implementation and maintenance of this corridor. Initially, we surveyed geoindicators and the distribution of forest remnants in the Ribeirão Anhumas watershed, where the corridor is inserted. Subsequently, we developed an impact assessment matrix to quantify the main environmental damages affecting the forest remnants that make up this corridor. The results allowed us to identify the most impacting actions on the corridor: agriculture/monoculture, deforestation, burning, urbanization, and land use and occupation, with quantification (Q) averages of -7.6; -8.3; -7.3; -8.1; and -7.3, respectively, resulting in a high damage percentage (66.7%) for each action. The diagnosis pointed to local scope, direct incidence, and current temporality, reinforcing the need to consider these factors for implementation and management of the quoted corridor.
{"title":"Diagnóstico ambiental dos fragmentos florestais pertencentes ao corredor ecológico Santa Genebrinha, Campinas, São Paulo","authors":"Joice Machado Garcia, Alessandra Leite da Silva, Catarina Araújo Siqueira, R. Longo","doi":"10.22571/2526-4338262","DOIUrl":"https://doi.org/10.22571/2526-4338262","url":null,"abstract":"Green areas, whether located in urban or rural environments, play an important role in maintaining ecological systems that provide vital environmental services for the quality of life of populations. In this sense, the present study assessed the environmental damage in the forest remnants that make up the Santa Genebrinha ecological corridor in Campinas city, São Paulo State, to identify limitations in the implementation and maintenance of this corridor. Initially, we surveyed geoindicators and the distribution of forest remnants in the Ribeirão Anhumas watershed, where the corridor is inserted. Subsequently, we developed an impact assessment matrix to quantify the main environmental damages affecting the forest remnants that make up this corridor. The results allowed us to identify the most impacting actions on the corridor: agriculture/monoculture, deforestation, burning, urbanization, and land use and occupation, with quantification (Q) averages of -7.6; -8.3; -7.3; -8.1; and -7.3, respectively, resulting in a high damage percentage (66.7%) for each action. The diagnosis pointed to local scope, direct incidence, and current temporality, reinforcing the need to consider these factors for implementation and management of the quoted corridor.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41645495","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}
Mylenna Nádja Ferreira de Sá, J. Lima, Fábio Nascimento De Jesus, J. Perez
Vigna unguiculata L. Walp (feijão-caupi) tem grande importância como fonte de alimento e como gerador de emprego e renda para a população rural brasileira. O tratamento de sementes por meio da microbiolização pode beneficiar a germinação de sementes, emergência e desenvolvimento das plântulas e produção de grãos. Objetivou-se com esta pesquisa avaliar o efeito da microbiolização na germinação e sanidade de sementes, assim como o crescimento inicial de plantas de Vigna unguiculata L. Walp cv. BRS Pujante. Os organismos utilizados na microbiolização das sementes foram Bacillus subtilis (LCB30), Bacillus subtilis (LCB45), Bacillus sp. (BMH), Bacillus sp. (INV) e Trichoderma sp. Avaliou-se o percentual de germinação, o crescimento da radícula e a incidência de fungos nas sementes microbiolizadas. Em viveiro, foram utilizados os mesmos microrganismos para microbiolização em um delineamento experimental inteiramente casualizado, com 4 repetições para teste de germinação, e 10 repetições para teste em casa de vegetação. Após 51 dias de crescimento das plantas, foram analisadas a massa fresca da parte aérea (MFPA) e da raiz (MFR), massa seca da parte aérea (MSPA) e da raiz (MSR) e a contagem de nódulos (NN). Todos os tratamentos proporcionaram o incremento na germinação de sementes de V. unguiculata BRS Pujante, exceto INV, com apenas 81% das sementes germinadas. Todas as sementes microbiolizadas reduziram a incidência de fungos. A microbiolização das sementes com os diferentes microrganismos não apresentou eficiência na nodulação das plantas. O isolado LCB 30 promoveu aumento significativo na MSPA e MSR de plantas de V. unguiculata.
{"title":"Microbiolização na qualidade de sementes e crescimento inicial de plantas de Vigna unguiculata L. Walp","authors":"Mylenna Nádja Ferreira de Sá, J. Lima, Fábio Nascimento De Jesus, J. Perez","doi":"10.22571/2526-4338176","DOIUrl":"https://doi.org/10.22571/2526-4338176","url":null,"abstract":"Vigna unguiculata L. Walp (feijão-caupi) tem grande importância como fonte de alimento e como gerador de emprego e renda para a população rural brasileira. O tratamento de sementes por meio da microbiolização pode beneficiar a germinação de sementes, emergência e desenvolvimento das plântulas e produção de grãos. Objetivou-se com esta pesquisa avaliar o efeito da microbiolização na germinação e sanidade de sementes, assim como o crescimento inicial de plantas de Vigna unguiculata L. Walp cv. BRS Pujante. Os organismos utilizados na microbiolização das sementes foram Bacillus subtilis (LCB30), Bacillus subtilis (LCB45), Bacillus sp. (BMH), Bacillus sp. (INV) e Trichoderma sp. Avaliou-se o percentual de germinação, o crescimento da radícula e a incidência de fungos nas sementes microbiolizadas. Em viveiro, foram utilizados os mesmos microrganismos para microbiolização em um delineamento experimental inteiramente casualizado, com 4 repetições para teste de germinação, e 10 repetições para teste em casa de vegetação. Após 51 dias de crescimento das plantas, foram analisadas a massa fresca da parte aérea (MFPA) e da raiz (MFR), massa seca da parte aérea (MSPA) e da raiz (MSR) e a contagem de nódulos (NN). Todos os tratamentos proporcionaram o incremento na germinação de sementes de V. unguiculata BRS Pujante, exceto INV, com apenas 81% das sementes germinadas. Todas as sementes microbiolizadas reduziram a incidência de fungos. A microbiolização das sementes com os diferentes microrganismos não apresentou eficiência na nodulação das plantas. O isolado LCB 30 promoveu aumento significativo na MSPA e MSR de plantas de V. unguiculata.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48162584","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}
A. Moreira, Thales Martins Silva, G. P. G. Freschi
This study broadens the understanding of photochemical processes by calculating the quantum efficiency of the Hg-MDEL lamp and discusses the environmental application of this lamp model in advanced oxidative processes. This set of information is relevant to broaden the application of Hg-MDEL in various environmental studies. Thus, a photochemical reactor composed of a microwave-fired mercury-free mercury (Hg-MDEL) lamp (MW) was evaluated from KI/KIO3 actinometric studies. The emission spectra were characterized along the UV-A, UV-B, UV-C and visible regions by means of a spectroradiometer, displaying linear correlation with the microwave power variation applied. The photochemical conversion of KI / KIO3 to I3- was up to 0.073 mmol L-1 when the KI initial concentration was 0.1 mol L-1 and 0.65 mmol L-1 when the KI concentration was 0.7 mol L-1, applying a microwave power of 600 and 400 W respectively. These results indicate that the photon emission near the reactor is more significant for higher powers, actively contributing to the formation of I3-.
{"title":"Caracterização de reator fotoquímico para aplicações em processos oxidativos avançados","authors":"A. Moreira, Thales Martins Silva, G. P. G. Freschi","doi":"10.22571/2526-4338240","DOIUrl":"https://doi.org/10.22571/2526-4338240","url":null,"abstract":"This study broadens the understanding of photochemical processes by calculating the quantum efficiency of the Hg-MDEL lamp and discusses the environmental application of this lamp model in advanced oxidative processes. This set of information is relevant to broaden the application of Hg-MDEL in various environmental studies. Thus, a photochemical reactor composed of a microwave-fired mercury-free mercury (Hg-MDEL) lamp (MW) was evaluated from KI/KIO3 actinometric studies. The emission spectra were characterized along the UV-A, UV-B, UV-C and visible regions by means of a spectroradiometer, displaying linear correlation with the microwave power variation applied. The photochemical conversion of KI / KIO3 to I3- was up to 0.073 mmol L-1 when the KI initial concentration was 0.1 mol L-1 and 0.65 mmol L-1 when the KI concentration was 0.7 mol L-1, applying a microwave power of 600 and 400 W respectively. These results indicate that the photon emission near the reactor is more significant for higher powers, actively contributing to the formation of I3-.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43356209","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}
Denise Rubinho dos Santos Martins, J. C. Serra, Joel Carlos Zukowski Junior, M. Pedroza
Toxic metals are naturally present in the environment even if there is no anthropic action. Several methods are used for the removal of these metals from water and effluents, such as: chemical precipitation, oxidation/reduction, filtration, ion exchange, membrane separation, and adsorption. Biosorption stands out as an effective treatment because it has a high rate of renewal in nature, low production costs, and high removal of metals due to the possibility of recovery of the contaminant, either by incinerating the biomass or by desorbing it. Thus, this study identified some biochars used as adsorbents for the removal of copper, lead, chromium, and mercury in water. It can be concluded from this study that adsorption is a very efficient technique for removing or recovering heavy metals from the environment. These biocarbons are alternatives that can replace commercial activated carbon because, besides having a low production cost, they have been shown to efficiently remove metal ions, ensuring an effective treatment in compliance with effluent release standards.
{"title":"Efficiency of biochars in the removal of heavy metals","authors":"Denise Rubinho dos Santos Martins, J. C. Serra, Joel Carlos Zukowski Junior, M. Pedroza","doi":"10.22571/2526-4338242","DOIUrl":"https://doi.org/10.22571/2526-4338242","url":null,"abstract":"Toxic metals are naturally present in the environment even if there is no anthropic action. Several methods are used for the removal of these metals from water and effluents, such as: chemical precipitation, oxidation/reduction, filtration, ion exchange, membrane separation, and adsorption. Biosorption stands out as an effective treatment because it has a high rate of renewal in nature, low production costs, and high removal of metals due to the possibility of recovery of the contaminant, either by incinerating the biomass or by desorbing it. Thus, this study identified some biochars used as adsorbents for the removal of copper, lead, chromium, and mercury in water. It can be concluded from this study that adsorption is a very efficient technique for removing or recovering heavy metals from the environment. These biocarbons are alternatives that can replace commercial activated carbon because, besides having a low production cost, they have been shown to efficiently remove metal ions, ensuring an effective treatment in compliance with effluent release standards.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42862320","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}
Laís Alvares Fonseca, F. D. A. Braga, G. Fernandes
The natural regeneration of tree species in forested areas has been studied by several researches. This study aimed to evaluate the natural regeneration of tree species in Corymbia citriodora (Hook.) K. D. Hill & L. A. Johnson planted forest understory in Florestal, Minas Gerais, Brazil. Individuals with diameter at breast height (DBH) ≥ 5 cm were evaluated in seven 25 x 4 m plots randomly distributed. A phytosociological survey was carried out and the ecological groups and the dispersal syndromes of the regenerants were determined. We found 28 species belonging to 12 families, among which Fabacea and Annonaceae stood out. Density was 1,557 regenerants ha-1, and basal area was 23 m2 ha-1. The most important species were Psidium sp; Schefflera macrocarpa (Cham. & Schltdl.) Frodin; Pera glabrata (Schott) Poepp. ex Baill.; Astronium fraxinifolium Schott & Spreng.; Matayba guianensis Aubl.; and Plathymenia reticulata Benth. We found 35% pioneer, 40% early secondary, 18% late secondary, and 7% climax species, of which 57% are zoochoric, 40% anemochoric, and 3% autochoric. It is concluded that the natural regeneration in the understory studied comprises typical species of the Seasonal Semideciduous Forest of the Atlantic Forest biome, presenting significant density and individuals from all ecological groups.The natural regeneration of tree species in forested areas has been studied by several researches. This study aimed to evaluate the natural regeneration of tree species in Corymbia citriodora (Hook.) K. D. Hill & L. A. Johnson planted forest understory in Florestal, Minas Gerais, Brazil. Individuals with diameter at breast height (DBH) ≥ 5 cm were evaluated in seven 25 x 4 m plots randomly distributed. A phytosociological survey was carried out and the ecological groups and the dispersal syndromes of the regenerants were determined. We found 28 species belonging to 12 families, among which Fabacea and Annonaceae stood out. Density was 1,557 regenerants ha-1, and basal area was 23 m2 ha-1. The most important species were Psidium sp; Schefflera macrocarpa (Cham. & Schltdl.) Frodin; Pera glabrata (Schott) Poepp. ex Baill.; Astronium fraxinifolium Schott & Spreng.; Matayba guianensis Aubl.; and Plathymenia reticulata Benth. We found 35% pioneer, 40% early secondary, 18% late secondary, and 7% climax species, of which 57% are zoochoric, 40% anemochoric, and 3% autochoric. It is concluded that the natural regeneration in the understory studied comprises typical species of the Seasonal Semideciduous Forest of the Atlantic Forest biome, presenting significant density and individuals from all ecological groups.
{"title":"Natural regeneration of tree species in the understory of Corymbia citriodora in Florestal city, Minas Gerais, Brazil","authors":"Laís Alvares Fonseca, F. D. A. Braga, G. Fernandes","doi":"10.22571/2526-4338244","DOIUrl":"https://doi.org/10.22571/2526-4338244","url":null,"abstract":"The natural regeneration of tree species in forested areas has been studied by several researches. This study aimed to evaluate the natural regeneration of tree species in Corymbia citriodora (Hook.) K. D. Hill & L. A. Johnson planted forest understory in Florestal, Minas Gerais, Brazil. Individuals with diameter at breast height (DBH) ≥ 5 cm were evaluated in seven 25 x 4 m plots randomly distributed. A phytosociological survey was carried out and the ecological groups and the dispersal syndromes of the regenerants were determined. We found 28 species belonging to 12 families, among which Fabacea and Annonaceae stood out. Density was 1,557 regenerants ha-1, and basal area was 23 m2 ha-1. The most important species were Psidium sp; Schefflera macrocarpa (Cham. & Schltdl.) Frodin; Pera glabrata (Schott) Poepp. ex Baill.; Astronium fraxinifolium Schott & Spreng.; Matayba guianensis Aubl.; and Plathymenia reticulata Benth. We found 35% pioneer, 40% early secondary, 18% late secondary, and 7% climax species, of which 57% are zoochoric, 40% anemochoric, and 3% autochoric. It is concluded that the natural regeneration in the understory studied comprises typical species of the Seasonal Semideciduous Forest of the Atlantic Forest biome, presenting significant density and individuals from all ecological groups.The natural regeneration of tree species in forested areas has been studied by several researches. This study aimed to evaluate the natural regeneration of tree species in Corymbia citriodora (Hook.) K. D. Hill & L. A. Johnson planted forest understory in Florestal, Minas Gerais, Brazil. Individuals with diameter at breast height (DBH) ≥ 5 cm were evaluated in seven 25 x 4 m plots randomly distributed. A phytosociological survey was carried out and the ecological groups and the dispersal syndromes of the regenerants were determined. We found 28 species belonging to 12 families, among which Fabacea and Annonaceae stood out. Density was 1,557 regenerants ha-1, and basal area was 23 m2 ha-1. The most important species were Psidium sp; Schefflera macrocarpa (Cham. & Schltdl.) Frodin; Pera glabrata (Schott) Poepp. ex Baill.; Astronium fraxinifolium Schott & Spreng.; Matayba guianensis Aubl.; and Plathymenia reticulata Benth. We found 35% pioneer, 40% early secondary, 18% late secondary, and 7% climax species, of which 57% are zoochoric, 40% anemochoric, and 3% autochoric. It is concluded that the natural regeneration in the understory studied comprises typical species of the Seasonal Semideciduous Forest of the Atlantic Forest biome, presenting significant density and individuals from all ecological groups.","PeriodicalId":41699,"journal":{"name":"Acta Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45085943","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}
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