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1.
Nature ; 628(8009): 776-781, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658683

RESUMO

Dissolved organic matter (DOM) is one of the most complex, dynamic and abundant sources of organic carbon, but its chemical reactivity remains uncertain1-3. Greater insights into DOM structural features could facilitate understanding its synthesis, turnover and processing in the global carbon cycle4,5. Here we use complementary multiplicity-edited 13C nuclear magnetic resonance (NMR) spectra to quantify key substructures assembling the carbon skeletons of DOM from four main Amazon rivers and two mid-size Swedish boreal lakes. We find that one type of reaction mechanism, oxidative dearomatization (ODA), widely used in organic synthetic chemistry to create natural product scaffolds6-10, is probably a key driver for generating structural diversity during processing of DOM that are rich in suitable polyphenolic precursor molecules. Our data suggest a high abundance of tetrahedral quaternary carbons bound to one oxygen and three carbon atoms (OCqC3 units). These units are rare in common biomolecules but could be readily produced by ODA of lignin-derived and tannin-derived polyphenols. Tautomerization of (poly)phenols by ODA creates non-planar cyclohexadienones, which are subject to immediate and parallel cycloadditions. This combination leads to a proliferation of structural diversity of DOM compounds from early stages of DOM processing, with an increase in oxygenated aliphatic structures. Overall, we propose that ODA is a key reaction mechanism for complexity acceleration in the processing of DOM molecules, creation of new oxygenated aliphatic molecules and that it could be prevalent in nature.


Assuntos
Carbono , Água Doce , Carbono/análise , Carbono/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Água Doce/química , Lagos/química , Lignina/química , Oxirredução , Oxigênio/química , Polifenóis/química , Rios/química , Suécia , Taninos/química , Ciclo do Carbono
2.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257382

RESUMO

Schinus terebinthifolius Raddi, popularly known as "Pink pepper", is a plant native to Brazil. The objective of this work was to analyze the chemical composition and the antioxidant and antibacterial potential of essential oils (EOs) from the leaves, fruits and twigs of S. terebinthifolius, aiming for their application in food safety. EOs were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrometry. Phenolic compounds were quantified and antioxidant activity was evaluated using three different methods. The antibacterial activity was determined by the broth microdilution method against foodborne bacteria. In the chemical analysis, 22 compounds were identified in the leaves, 13 compounds in the fruits and 37 compounds in the twigs, revealing the presence of the main compounds germacrene D (12.04%, 15.78%, 20,41%), caryophyllene (15.97%, 3.12%, 11.73%), α-pinene (11.6%, 17.16%, 2.99%), ß-pinene (5.68%, 43.34%, 5.60%) and γ-gurjunene (16,85%, 3,15%) respectively. EOs showed better antioxidant potential using the ß-carotene/linoleic acid method with 40.74, 61.52 and 63.65% oxidation inhibition for leaves, fruits and twigs, respectively. The EO from the leaves showed greater antibacterial potential against Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 0.62 mg mL-1, a value lower than the MIC of sodium nitrite (5.00 mg mL-1), the antimicrobial standard synthetic. The activities of pink pepper EOs suggest their potential as a biopreservative in foods.


Assuntos
Óleos Voláteis , Piper nigrum , Frutas , Antioxidantes/farmacologia , Schinus , Óleos Voláteis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia , Escherichia coli
3.
Photochem Photobiol Sci ; 22(3): 669-686, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36417143

RESUMO

The mycelial biomass of basidiomycetes is a promising source of compounds and represents an alternative for industrial and biotechnological applications. Fungi use light as information and hold photoresponse mechanisms, in which sensors respond to light wavelengths and regulate various biological processes. Therefore, this study aimed to investigate the effects of blue, green, and red lights on the growth, chemical composition, and antioxidant and antimicrobial activity of Lentinus crinitus mycelial biomass. The chemical composition of the mycelial biomass was determined by chromatographic methods, antioxidant activity was analyzed by in vitro assays, and antimicrobial activity was investigated by the microdilution assay. The highest mycelial biomass yield was observed under blue-light cultivation. Many primordia arose under blue or green light, whereas the stroma was formed under red light. The presence of light altered the primary fungal metabolism, increasing the carbohydrate, tocopherol, fatty acid, and soluble sugar contents, mostly mannitol, and reducing the protein and organic acid concentrations. Cultivation under red light increased the phenol concentration. In contrast, cultivation under blue and green lights decreased phenol concentration. Benzoic and gallic acids were the main phenolic acids in the hydroalcoholic extracts, and the latter acids increased in all cultures under light, especially red light. Mycelial biomass cultivated under red light showed the highest antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ferric reducing antioxidant power (FRAP) method showed that all light wavelengths increased the antioxidant activity of mycelial biomass, with the highest value under red light. Moreover, the ß-carotene/linoleic acid co-oxidation (BCLA) assay demonstrated that the antioxidant activity was affected by light cultivation. Mycelial biomass grown under all conditions exhibited antibacterial and antifungal activities. Thus, mycelial biomass cultivation of L. crinitus under light conditions may be a promising strategy for controlling the mycelial chemical composition and biomass yield.


Assuntos
Anti-Infecciosos , Basidiomycota , Lentinula , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Biomassa , Lentinula/metabolismo , Basidiomycota/metabolismo , Fenóis/metabolismo
4.
Molecules ; 28(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513277

RESUMO

Gallesia integrifolia, a notable species in the Atlantic Forest, has been traditionally employed in folk medicine for treating rheumatism, asthma, and worms. This study investigated the cellular antioxidant, antiproliferative, and anti-inflammatory activities of the essential oils (EOs) and crude extracts (CEs) from G. integrifolia flowers, fruits, and leaves. The chemical identification of EOs was performed by GC-MS and CEs by UHPLC-MS. Cellular antioxidant and anti-inflammatory activities were assessed through mouse macrophage cell culture. In addition, the antiproliferative potential was evaluated in gastric, colorectal, breast, and lung tumor cell lines and non-tumor VERO cells. EOs predominantly contained organosulfur compounds in flowers (96.29%), fruits (94.94%), and leaves (90.72%). We found the main compound is 2,2'-Disulfanediyldiethanethiol in the EOs of flowers (47.00%), leaves (41.82%), and fruits (44.39%). Phenolic compounds were identified in CEs. The EOs and CEs demonstrated potential against the tumor cell lines tested (GI50 between 51 and 230 µg/mL). The selectivity index values were greater than 1.0 (1.01 to 3.37), suggesting a relative safety profile. Moreover, the anti-inflammatory activity IC50 ranged from 36.00 to 268 µg/mL, and the cellular oxidation inhibition ranged from 69% to 82%. The results suggest that oils and extracts derived from G. integrifolia have potential for use in various industrial sectors.


Assuntos
Antioxidantes , Óleos Voláteis , Camundongos , Animais , Chlorocebus aethiops , Antioxidantes/farmacologia , Antioxidantes/análise , Frutas , Células Vero , Folhas de Planta/química , Flores/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análise , Óleos Voláteis/química , Extratos Vegetais/química
5.
World J Microbiol Biotechnol ; 39(5): 110, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36905533

RESUMO

Conventional textile effluent treatments cannot remove methylene blue, a mutagenic azo dye, and an endocrine disruptor, that remains in the drinking water after conventional water treatment. However, the spent substrate from Lentinus crinitus mushroom cultivation, a waste, could be an attractive alternative to remove persistent azo dyes in water. The objective of this study was to assess the methylene blue biosorption by spent substrate from L. crinitus mushroom cultivation. The spent substrate obtained after mushroom cultivation had been characterized by the point of zero charge, functional groups, thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Moreover, the spent substrate biosorption capacity was determined in function of pH, time, and temperature. The spent substrate had a point of zero charge value of 4.3 and biosorbed 99% of methylene blue in pH from 3 to 9, with the highest biosorption in the kinetic assay of 15.92 mg g- 1, and in the isothermal assay of 120.31 mg g- 1. Biosorption reached equilibrium at 40 min after mixing and best fitted the pseudo-second-order model. Freundlich model best fitted the isothermal parameters and each 100 g spent substrate biosorbed 12 g dye in an aqueous solution. The spent substrate of L. crinitus cultivation is an effective biosorbent of methylene blue and an alternative to removing this dye from water, adding value to the mushroom production chain, and supporting the circular economy.


Assuntos
Agaricales , Poluentes Químicos da Água , Termodinâmica , Azul de Metileno , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise , Adsorção , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos Azo , Corantes
6.
World J Microbiol Biotechnol ; 38(6): 94, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35441989

RESUMO

Brunfelsia uniflora (Pohl.) D. Don (Solanaceae), commonly known as manacá-de-cheiro, is widely distributed in Brazil and used by local indigenous peoples as an antirheumatic, antisyphilitic, depurative, emetic, vermifuge, and purgative agent. Several studies have examined the biological activities and phytochemical profile of Brunfelsia; however, few have focused on the diversity of endophytic microorganisms that colonize members of the genus. This study aimed to isolate and cryopreserve endophytic fungi from B. uniflora and determine their cellulase, laccase, and antioxidant activities. Endophytic fungi were isolated from B. uniflora stems, cultured on wheat grains, immersed in a 150 g L-1 aqueous sucrose solution, and cryopreserved at - 80 °C for 1 and 6 months. Cellulase activity was determined by a qualitative test using carboxymethylcellulose medium and laccase activity by a quantitative test based on the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate). Prior to antioxidant activity assays, fungi were grown in malt extract broth for production of mycelial biomass. A methanolic extract was prepared for evaluation of DPPH· scavenging activity, FRAP activity, and total phenolic content. A total of 46 endophytic fungal isolates were obtained from B. uniflora stems and classified into 24 groups according to morphological similarities. B. uniflora was shown to harbor different genera of ascomycete fungi as endophytic organisms. Mycelial viability was observed after 1 and 6 months of cryopreservation at - 80 °C. Fungi exhibited cellulase and laccase activities. Isolate CE23 had the highest laccase activity after 7 days of cultivation. Twelve isolates were found to have low total phenolic contents and DPPH· and FRAP activities.


Assuntos
Ascomicetos , Celulase , Solanaceae , Antioxidantes/química , Criopreservação , Endófitos/química , Fungos , Lacase , Fenóis , Extratos Vegetais/química
7.
World J Microbiol Biotechnol ; 38(5): 74, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35298734

RESUMO

Lentinus crinitus basidiocarps are an alternative to antimicrobials, but the stipe (24% basidiocarp) is discarded even with potential antimicrobial activity. This study evaluated the antimicrobial activity of L. crinitus basidiocarp pileus and stipe extracts against foodborne pathogens and food spoilage microorganisms. Basidiocarps of L. crinitus were grown in sugarcane bagasse and rice husks and the pileus and stipe methanolic extract was analyzed by broth microdilution method for antimicrobial activity against eight bacteria and eight fungi. The minimum bactericidal concentration values for pileus and stipe ranged from 0.40 to 0.50 mg mL- 1, for streptomycin from 0.10 to 0.50 mg mL- 1, and for ampicillin from 0.40 to 1.20 mg mL- 1. The minimum fungicidal concentration values for pileus and stipe ranged from 0.06 to 0.60 mg mL- 1, for bifonazole from 0.20 to 0.25 mg mL- 1, and for ketoconazole from 0.30 to 3.50 mg mL- 1. Extracts had bacteriostatic, bactericidal, fungistatic and fungicidal activity against all microorganisms, but with greater efficiency and specificity for some microorganisms. Both pileus and stipe are promising and sustainable alternatives for use in food, agricultural, and pharmaceutical industries.


Assuntos
Anti-Infecciosos , Saccharum , Anti-Infecciosos/química , Celulose , Carpóforos , Lentinula , Testes de Sensibilidade Microbiana
8.
An Acad Bras Cienc ; 92 Suppl 2: e20191350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813769

RESUMO

Iron and zinc bioaccumulation in mycelial biomass of different medicinal basidiomycetes was evaluated in order to produce metal-enriched mycelial biomass as an alternative functional food from non-animal sources and based on biotechnology processes. Pleurotus ostreatus strain U2-9, U2-11, U6-8, and U6-9, Pleurotus eryngii strain U8-11, Schizophyllum commune strain U6-7, and Lentinula edodes strain U6-11 and U6-12 were grown in malt extract agar with or without addition of 50 mg/L iron or 7.5 mg/L zinc. The mycelial biomass was separated and iron and zinc concentrations were determined in a flame atomic absorption spectrophotometer. Basidiomycete strains presented different growth rates with the presence of iron and zinc; there was no dependence between the metal bioaccumulation and the fungal growth. The fungi presented greater capacity to bioaccumulate iron than zinc. P. ostreatus (U2-9) has greater iron bioaccumulation (3197.7 mg/kg) while P. ostreatus (U6-8) greater zinc bioaccumulation (440.4 mg/kg) in mycelial biomass. P. ostreatus (U2-9), P. ostreatus (U2-11), and S. commune (U6-7) had the highest metal translocation rates from the culture medium to mycelial biomass. The mycelial biomass enriched with iron or zinc is an alternative to a new functional food from non-animal sources.


Assuntos
Biomassa , Pleurotus , Ferro , Micélio , Zinco
9.
An Acad Bras Cienc ; 90(4): 3463-3473, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29947669

RESUMO

Lentinus crinitus is a white-rot fungus that produces laccase, an enzyme used for dye decolorization. Enzyme production depends on cultivation conditions, mainly agro-industrial by-products. We aimed to produce laccase from Lentinus crinitus with agro-industrial by-products for dye decolorization. Culture medium had coffee husk (CH) or citric pulp pellet (CP) and different nitrogen sources (urea, yeast extract, ammonium sulfate and sodium nitrate) at concentrations of 0, 0.7, 1.4, 2.8, 5.6 and 11.2 g/L. Enzymatic extract was used in the decolorization of remazol brilliant blue R. CH medium promoted greater laccase production than CP in all evaluated conditions. Urea provided the greatest laccase production for CH (37280 U/L) as well as for CP (34107 U/L). In CH medium, laccase activity was suppressed when carbon-to-nitrogen ratio changed from 4.5 to 1.56, but the other nitrogen concentrations did not affect laccase activity. For CP medium, reduction in carbon-to-nitrogen ratio from 6 to 1.76 increased laccase activity in 17%. The peak of laccase activity in CH medium occurred on the 11th day (41246 U/L) and in CP medium on the 12th day (32660 U/L). The maximum decolorization within 24 h was observed with CP enzymatic extract (74%) and with CH extract (76%).


Assuntos
Antraquinonas/farmacologia , Corantes/farmacologia , Meios de Cultura/farmacologia , Lacase/farmacologia , Lentinula/química
10.
Int Urogynecol J ; 28(8): 1165-1170, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28035442

RESUMO

INTRODUCTION AND HYPOTHESIS: Although pelvic organ prolapse (POP) is a prevalent condition among Brazilians, population-based epidemiological studies of POP are scarce. We studied POP in a population of women undergoing routine examination to determine its prevalence, distribution and relationship to risk factors. METHODS: This quantitative descriptive study surveyed 432 women, based on prolapse prevalence, who sought routine care and were assessed for prolapse staging using the Pelvic Organ Prolapse Quantification system (POP-Q). Demographics, health history, socioeconomic data, symptoms and risk factors for prolapse were self-reported by the participants. RESULTS: A total of 226 (52.3%) of the examined women had POP. The prevalences of POP in relation to stage were as follows: stage 1 (27.8%), stage 2 (23.1%), and stage 3 (1.4%). Regarding risk factors, a history of vaginal delivery (odds ratio, OR, 6.678, 95% confidence interval, CI, 4.16-10.73), delivery of a newborn heavier than 4 kg (OR 2.056, 95% CI 1.19-3.56) and menopausal status (OR 2.793, 95% CI 1.66-4.70) were all associated with a higher risk of prolapse. CONCLUSIONS: We found that a majority of the population sample exhibited some degree of prolapse, suggesting that POP deserves substantial clinical attention. The risk factors identified suggest that eventual prolapse may be unavoidable in some women. Public policies should be implemented with respect to modifiable risk factors and antenatal care.


Assuntos
Prolapso de Órgão Pélvico/epidemiologia , Prolapso de Órgão Pélvico/etiologia , Adulto , Brasil/epidemiologia , Parto Obstétrico/efeitos adversos , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Gravidez , Prevalência , Fatores de Risco , Inquéritos e Questionários
11.
PLoS Genet ; 7(5): e1002064, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21589895

RESUMO

The molecular mechanisms of plant recognition, colonization, and nutrient exchange between diazotrophic endophytes and plants are scarcely known. Herbaspirillum seropedicae is an endophytic bacterium capable of colonizing intercellular spaces of grasses such as rice and sugar cane. The genome of H. seropedicae strain SmR1 was sequenced and annotated by The Paraná State Genome Programme--GENOPAR. The genome is composed of a circular chromosome of 5,513,887 bp and contains a total of 4,804 genes. The genome sequence revealed that H. seropedicae is a highly versatile microorganism with capacity to metabolize a wide range of carbon and nitrogen sources and with possession of four distinct terminal oxidases. The genome contains a multitude of protein secretion systems, including type I, type II, type III, type V, and type VI secretion systems, and type IV pili, suggesting a high potential to interact with host plants. H. seropedicae is able to synthesize indole acetic acid as reflected by the four IAA biosynthetic pathways present. A gene coding for ACC deaminase, which may be involved in modulating the associated plant ethylene-signaling pathway, is also present. Genes for hemagglutinins/hemolysins/adhesins were found and may play a role in plant cell surface adhesion. These features may endow H. seropedicae with the ability to establish an endophytic life-style in a large number of plant species.


Assuntos
Genoma de Planta , Herbaspirillum/genética , Cromossomos de Plantas , Herbaspirillum/metabolismo , Interações Hospedeiro-Patógeno , Fixação de Nitrogênio , Pressão Osmótica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
World J Microbiol Biotechnol ; 30(8): 2307-13, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24770840

RESUMO

Basidiocarp of Agaricus blazei (=Agaricus brasiliensis; =Agaricus subrufescens) is used as teas or capsules due to its antineoplastic effect but there are few reports of using mycelium for this purpose. The objective of this study was to evaluate the antineoplastic activity on sarcoma 180 cells implanted in mice of two forms of preparation of the mycelium from two A. blazei strains grown in culture medium with different concentrations of isolated soy protein. Mycelia were grown in Pontecorvo medium with different concentrations of isolated soybean protein (ISP). Mycelial hot water extract, moistened mycelial powder, hot water extract of green tea, Ifosfamida(®) (ifosfamide drug), and saline solution were administered daily by gavage in mice with sarcoma 180 cells to evaluate antineoplastic activity. It was concluded that antineoplastic activity was the same for both strains, except when used as moistened mycelial powder, which rules out the use of mycelial powder in capsules. Mycelial hot water extract had high antineoplastic activity with lower metabolic demand on the spleen and maintenance of normal blood parameters. Mycelial growth in different ISP concentrations had the same antineoplastic activity. Also the vegetative mycelium was as effective as the basidiocarp for sarcoma 180 tumor inhibition. Green tea was as effective as mycelial hot water extract.


Assuntos
Agaricus/química , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Micélio/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Sarcoma 180/tratamento farmacológico , Animais , Meios de Cultura/química , Vias de Administração de Medicamentos , Composição de Medicamentos , Feminino , Ifosfamida/uso terapêutico , Camundongos , Fitoterapia , Sarcoma 180/patologia , Proteínas de Soja/farmacologia
13.
Nat Prod Res ; : 1-6, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726900

RESUMO

The chemical composition of Pachira aquatica crude extracts flowers, leaves, and seeds was obtained by UHPLC-ESI/qTOF and GC/MS. The antiproliferative activity was evaluated against the human tumour cell lines AGS (gastric), CaCo-2 (colorectal), MCF-7 (breast), and NCI-H460 (lung). The anti-inflammatory and cellular antioxidant activities were also studied. Flavonoids, phenolic acids, coumarins, and saturated fatty acids were identified in the samples. The concentration of extracts responsible for inhibiting 50% of nitric oxide production ranged from (149 to > 400 µg mL-1). Antiproliferative activity against the tumour cell lines was: AGS (GI50 175 to > 400 µg mL-1), Caco-2 (GI50 215 to > 400 µg mL-1), MCF7 (GI50 232 to > 400 µg mL-1) and NCI-H460 (GI50 208 to > 400 µg mL-1). Cellular antioxidant activity remained between 73% to > 2000%. The selectivity index (SI) ranged from 1.00 to 2.78, indicating low antiproliferative activity.

14.
ACS ES T Water ; 3(8): 2083-2095, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37588807

RESUMO

Positive and negative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and 1H NMR revealed major compositional and structural changes of dissolved organic matter (DOM) after mixing two sets of river waters in Amazon confluences: the Solimões and Negro Rivers (S + N) and the Amazon and Tapajós Rivers (A + T). We also studied the effects of water mixing ratios and incubation time on the composition and structure of DOM molecules. NMR spectra demonstrated large-scale structural transformations in the case of S + N mixing, with gain of pure and functionalized aliphatic units and loss of all other structures after 1d incubation. A + T mixing resulted in comparatively minor structural alterations, with a major gain of small aliphatic biomolecular binding motifs. Remarkably, structural alterations from mixing to 1d incubation were in essence reversed from 1d to 5d incubation for both S + N and A + T mixing experiments. Heterotrophic bacterial production (HBP) in endmembers S, N, and S + N mixtures remained near 0.03 µgC L-1 h-1, whereas HBP in A, T, and A + T were about five times higher. High rates of dark carbon fixation took place at S + N mixing in particular. In-depth biogeochemical characterization revealed major distinctions between DOM biogeochemical changes and temporal evolution at these key confluence sites within the Amazon basin.

15.
Sci Total Environ ; 857(Pt 3): 159620, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36280052

RESUMO

Rivers are natural biogeochemical systems shaping the fates of dissolved organic matter (DOM) from leaving soils to reaching the oceans. This study focuses on Amazon basin DOM processing employing negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI[±] FT-ICR MS) and nuclear magnetic resonance spectroscopy (NMR) to reveal effects of major processes on the compositional space and structural characteristics of black, white and clear water systems. These include non-conservative mixing at the confluences of (1) Solimões and the Negro River, (2) the Amazon River and the Madeira River, and (3) in-stream processing of Amazon River DOM between the Madeira River and the Tapajós River. The Negro River (black water) supplies more highly oxygenated and high molecular weight compounds, whereas the Solimões and Madeira Rivers (white water) contribute more CHNO and CHOS molecules to the Amazon River main stem. Aliphatic CHO and abundant CHNO compounds prevail in Tapajos River DOM (clear water), likely originating from primary production. Sorption onto particles and heterotrophic microbial degradation are probably the principal mechanisms for the observed changes in DOM composition in the Amazon River and its tributaries.


Assuntos
Rios , Espectrometria de Massas por Ionização por Electrospray , Rios/química , Matéria Orgânica Dissolvida , Espectroscopia de Ressonância Magnética , Água
16.
Animals (Basel) ; 13(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37048403

RESUMO

Bovine mastitis is an inflammation of the mammary gland in response to invasion by opportunistic agents. Due to the high economic importance of dairy production and the complexity related to animal health, the objective of this work was to identify and evaluate the antibacterial resistance profile of samples of mastitis milk, milking hand and milking equipment from small rural dairy farms belonging to the northwest region of the state of Paraná, Brazil. Five small, non-technical dairy farms in the municipalities of Boa Esperança, Juranda and Tapejara, all belonging to the northwest region of the state of Paraná, Brazil, were selected. The properties had Holstein and/or crossbred herds, carried out a bucket-by-foot milking system and all had the presence of animals with subclinical mastitis confirmed by the California Mastitis Test. Samples of sterile swabs from the milking insufflators, the milking hand and milk samples were collected-and later, isolation tests and phenotypic characterization of the samples, sensitivity tests to antimicrobials and phenotypic tests for the detection of beta-producing strains were performed with extended-spectrum beta-lactamase (ESBL), molecular identification of Staphylococcus aureus isolates and mecA gene research. Of the 199 samples collected from the 15 selected properties in the municipalities of Boa Esperança, Tapejara and Juranda, 72 (36.20%) were classified as multiresistant. Isolated from milkers' hands and milking machines, which phenotypically produce extended-spectrum beta-lactamase (ESBL), the presence of the mecA gene was also observed in 11 isolates of Staphylococcus spp. of milk samples, machines and milking hands. Mastitis can be spread to the herd through the milking process by the milkers' instruments and hands, and adequate management measures can prevent its transmission and the conscious use of antibiotics decreases the prevalence of multidrug-resistant pathogens. In this work, different pathogenic bacteria were detected in mastitic milk, milking equipment and milking hand with a high percentage (36.20%) of isolates classified as multidrug resistant. In addition, the presence phenotypically (ESBL) and molecularly (mecA gene) of isolates carrying resistance genes was also verified. These results directly reflect on the health of the animals, the health of the workers and the health of the respective environment, which can enable the continuity of the propagation of the etiological agents involved in the mastitis infection. The awareness of producers and workers on these properties about the disease, transmission, sanitary aspects and adequate management and treatment are essential for improving milk production and production efficiency.

17.
Indian J Microbiol ; 52(3): 484-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23997343

RESUMO

Alternative substrates for cryopreservation at -20 °C have been little explored for basidiomycetes and could bring new possibilities of lower cost cryopreservation. Nevertheless, freezing temperatures between -15 and -60 °C are very challenging because they frequently result in cryoinjuries. The objective of this study was to evaluate substrates associated to cryoprotective agents for Pleurotus ostreatus cryopreservation at -20 or -70 °C in order to develop alternative techniques for basidiomycete cryopreservation. P. ostreatus was grown on potato dextrose agar or whole grains of oat, wheat, rice or millet and transferred to cryovials with cryoprotective solution with 1 % dimethyl sulfoxide, 5 % glycerol, 10 % saccharose, 4 % glucose, 6 % polyethylene glycol-6000 or 5 % malt extract. The mycelium in the cryovials were cryopreserved at -20 or -70 °C and recovered for evaluation of the mycelial growth viability after 1 and 3 years. Both substrates and cryoprotectants affect the viability of the mycelial growth cryopreserved at -20 or -70 °C; wheat grains combined with cryoprotectants such as saccharose or glucose are effective for keeping mycelium viable after cryopreservation at -20 °C for 1 or 3 years; for cryopreservation at -70 °C after 1 or 3 years, any substrate combined with any cryoprotectant is effective for preserving the mycelium viable, except for millet grains with polyethylene glycol after 3 years; semi-permeable cryoprotective agents such as saccharose and glucose are the most effective for cryopreservation at -20 or -70 °C for at least 3 years.

18.
Front Pharmacol ; 13: 1048688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518668

RESUMO

Baccharis dracunculifolia DC (Lamiaceae) (Asteraceae) is found in South America, mainly in Argentina, Brazil, Bolivia, Paraguay and Uruguay. Folk medicine is used as a sedative, hypotensive, bronchodilator, cardiovascular disorders, anti-flu, and also in skin wounds. Considered the main source of green propolis, which increases the pharmacological interest in this species. It is also known as a "benefactor" plant facilitating the development of other plant species around it, being indicated for the recovery of degraded areas. This species has been studied for decades in order to isolate and identify the active principles present in the aerial parts (leaves and flowers) and roots. The present study consists of a review of the scientific literature addressing the ethnobotanical, ethnomedicinal, phytochemical, pharmacological and potential cytotoxic effects of the B. dracunculifolia species. In this survey, we sought to investigate issues related to the botanical and geographic description of the species, the ethnobotanical uses, as well as the phytochemical studies of the essential oil, extracts and green propolis obtained from the aerial parts and roots of B. dracunculifolia. Using high precision analytical tools, numerous compounds have already been isolated and identified from leaves and flowers such as the flavonoids: naringenin, acacetin, dihydrokaempferol, isosakuranetin and kaempferide; phenolic acids: p-coumaric, dihydrocoumaric, ferulic (E)-cinnamic, hydroxycinnamic, gallic, caffeic, and several caffeoylquinic acids derivatives; phenolic acids prenylated: artepillin C, baccharin, drupanin; the glycosides dracuculifosides and the pentacyclic triterpenoids: Baccharis oxide and friedelanol. The predominant class in the essential oil of leaves and flowers are terpenoids comprising oxygenated monoterpenes and sesquiterpenes, highlighting the compounds nerolidol, spathulenol, germacrene D and bicyclogermacrene. These compounds give the species high antimicrobial, antioxidant, antitumor, analgesic, immunomodulatory and antiparasitic potential, making this species a promising herbal medicine. In vitro toxicity assays with B. dracunculifolia extract showed low or no cytotoxicity. However, in vivo analyses with high doses of the aqueous extract resulted in genotoxic effects, which leads us to conclude that the toxicity of this plant is dose-dependent.

19.
Environ Technol ; 43(8): 1248-1254, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32928067

RESUMO

Iron bioaccumulation in basidiomycetes is an alternative to recover ferrous sulphate from titanium dioxide pigment production and to produce an iron-enriched mycelial biomass. This study aimed to evaluate iron bioaccumulation capacity in vegetative mycelium of edible and medicinal fungi grown in malt extract liquid medium with different ferrous sulphate contents. Five basidiomycetes were grown in malt extract liquid medium with different iron contents from 0.116 to 100 mg L-1 iron. The iron content of dried mycelial biomass bioaccumulated with iron was determined by flame atomic absorption spectrophotometry. All fungi grew on the iron culture media and the mycelial biomass growth ranged from 3.24 ± 0.65a mg mL-1 to 12.46 ± 0.29 mg mL-1. Iron addition to culture media increased the iron content in the mycelial biomass from 4000-13,000-fold compared with control. Pleurotus ostreatus (2181 ± 218 mg kg-1) presented the greatest iron content in the mycelial biomass, followed by Schizophyllum commune (1769 ± 131 mg kg-1), Agaricus subrufescens (1272 ± 8.84 mg kg-1), and Ganoderma lucidum (840 ± 75 mg kg-1). P. ostreatus, followed by S. commune, and G. lucidum at 90 and 100 mg L-1 iron in the culture medium are the best choices to produce iron-enriched mycelial biomass. This extensive study of several edible and medicinal basidiomycetes grown in different iron contents was effective in recovering ferrous sulphate byproduct and transferring it to mycelium to produce a new nutraceutical food of iron-enriched mycelial biomass.


Assuntos
Ferro , Pleurotus , Biomassa , Meios de Cultura , Micélio
20.
J Microbiol Methods ; 198: 106491, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35588992

RESUMO

Lentinus crinitus (Basidiomycota: Polyporales) is a saprophytic fungus with biotechnological importance described more than 20 years ago. However, there are few studies on the long-term preservation of this basidiomycete. Cryopreservation is a long-term storage technique that reduces the metabolic activity of microorganisms, but its success depends on the adjustment of the freezing process, the cryoprotectants, and the protective substrates for each species. This study aimed to assess the mycelial viability and genetic stability of L. crinitus strains cryopreserved at -86 °C for two years by the wheat grain technique using different cryoprotectants and freezing methods. Three strains of L. crinitus (U9-1, U13-5, and U15-12) were subjected to different concentrations and types of cryoprotectants (dimethyl sulfoxide, glycerol, glucose, and sucrose), freezing methods such as immediate freezing from 25 to -86 °C and progressing freezing from 25 to -86 °C in a freezing container with isopropyl alcohol to control the rate of cell freezing at -1 °C min-1, protective substrate (wheat grain and 2% malt extract agar), and cryopreservation period (1, 6, 12, and 24 months). After thawing, samples were evaluated for mycelial viability, time to mycelial recovery, mycelial stability, and genetic stability of the fungus. All techniques achieved effective cryopreservation at -86 °C, mainly with the wheat grain technique. All cryoprotectants (3.5% glycerol, 1.5% dimethyl sulfoxide, 25% sucrose, and 5% glucose), freezing methods (immediate and gradual), and protective substrate (wheat grain and malt extract agar) were effective for cryopreservation of the three L.crinitus strains in an ultra-low temperature freezer for two years. Mycelial viability, mycelial stability, and genetic stability of the fungus were not affected after two-year cryopreservation, evidencing the robustness of the long-term cryopreservation technique and the fungus.


Assuntos
Basidiomycota , Dimetil Sulfóxido , Ágar , Basidiomycota/metabolismo , Criopreservação/métodos , Crioprotetores/farmacologia , Congelamento , Glucose , Glicerol , Lentinula , Extratos Vegetais , Sacarose , Triticum
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