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1.
Planta ; 259(1): 23, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108903

RESUMO

MAIN CONCLUSION: The ex vitro hairy root system from petioles of detached soybean leaves allows the functional validation of genes using classical transgenesis and CRISPR strategies (e.g., sgRNA validation, gene activation) associated with nematode bioassays. Agrobacterium rhizogenes-mediated root transformation has been widely used in soybean for the functional validation of target genes in classical transgenesis and single-guide RNA (sgRNA) in CRISPR-based technologies. Initial data showed that in vitro hairy root induction from soybean cotyledons and hypocotyls were not the most suitable strategies for simultaneous performing genetic studies and nematode bioassays. Therefore, an ex vitro hairy root system was developed for in planta screening of target molecules during soybean parasitism by root-knot nematodes (RKNs). Applying this method, hairy roots were successfully induced by A. rhizogenes from petioles of detached soybean leaves. The soybean GmPR10 and GmGST genes were then constitutively overexpressed in both soybean hairy roots and tobacco plants, showing a reduction in the number of Meloidogyne incognita-induced galls of up to 41% and 39%, respectively. In addition, this system was evaluated for upregulation of the endogenous GmExpA and GmExpLB genes by CRISPR/dCas9, showing high levels of gene activation and reductions in gall number of up to 58.7% and 67.4%, respectively. Furthermore, morphological and histological analyses of the galls were successfully performed. These collective data validate the ex vitro hairy root system for screening target genes, using classical overexpression and CRISPR approaches, directly in soybean in a simple manner and associated with nematode bioassays. This system can also be used in other root pathosystems for analyses of gene function and studies of parasite interactions with plants, as well as for other purposes such as studies of root biology and promoter characterization.


Assuntos
Soja , Nematoides , Animais , Soja/genética , RNA Guia de Sistemas CRISPR-Cas , Bioensaio , Cotilédone , Nematoides/genética
2.
Mikrochim Acta ; 190(8): 321, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491620

RESUMO

Neglected tropical diseases are those caused by infectious agents or parasites and are considered endemic in low-income populations. These diseases also have unacceptable indicators and low investment in research, drug production, and control. Tropical diseases such as leishmaniasis are some of the main causes of morbidity and mortality around the globe. Electrochemical immunosensors are promising tools for diagnostics against these diseases. One such benefit is the possibility of assisting diagnosis in isolated regions, where laboratory infrastructure is lacking. In this work, different peptides were investigated to detect antibodies against Leishmania in human and canine serum samples. The peptides evaluated (395-KKG and 395-G) have the same recognition site but differ on their solid-binding domains, which ensure affinity to spontaneously bind to either graphene oxide (GO) or graphene quantum dots (GQD). Cyclic voltammetry and differential pulse voltammetry were employed to investigate the electrochemical behavior of each assembly step and the role of each solid-binding domain coupled to its anchoring material. The graphene affinity peptide (395-G) showed better reproducibility and selectivity when coupled to GQD. Under the optimized set of experimental conditions, negative and positive human serum samples responses were distinguished based on a cut-off value of 82.5% at a 95% confidence level. The immunosensor showed selective behavior to antibodies against Mycobacterium leprae and Mycobacterium tuberculosis, which are similar antibodies and potentially sources of false positive tests. Therefore, the use of the graphene affinity peptide as a recognition site achieved outstanding performance for the detection of Leishmania antibodies.


Assuntos
Técnicas Biossensoriais , Grafite , Leishmaniose , Animais , Cães , Humanos , Carbono/química , Grafite/química , Reprodutibilidade dos Testes , Imunoensaio , Peptídeos , Anticorpos , Leishmaniose/diagnóstico
3.
Talanta ; 257: 124348, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801564

RESUMO

Electrochemical immunosensors are excellent alternatives to prepare portable platforms used for rapid and inexpensive diagnostic of infectious diseases such as the recently emerged COVID-19. Incorporating synthetic peptides as selective recognition layers combined with nanomaterials such as gold nanoparticles (AuNPs) can significantly enhance the analytical performance of immunosensors. In the present study, an electrochemical immunosensor based on solid-binding peptide was built and evaluated towards SARS-CoV-2 Anti-S antibodies detection. The peptide used as recognition site has two important portions: one based on the viral receptor binding domain (RBD), capable of recognizing antibodies of the spike protein (Anti-S), and another suitable for interacting with gold nanoparticles. Gold-binding peptide (Pept/AuNP) dispersion was used directly to modify a screen-printed carbon electrode (SPE). The voltammetric behavior of the [Fe(CN)6]3-/4- probe after every construction and detection step was recorded using cyclic voltammetry by assessing the stability of the Pept/AuNP as a recognition layer onto the electrode surface. Differential pulse voltammetry was used as a detection technique, and a linear working range from 75 ng mL-1 to 15 µg mL-1 was established, with 1.059 µA dec-1 of sensitivity and R2 = 0.984. The response selectivity against SARS-CoV-2 Anti-S antibodies was investigated in presence of concomitant species. The immunosensor was used to detect SARS-CoV-2 Anti-spike protein (Anti-S) antibodies in human serum samples, successfully differentiating between negative and positive responses of samples at a 95% confidence level. Therefore, the gold-binding peptide is a promising tool to be applied as a selective layer for antibody detection.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Humanos , Ouro/química , SARS-CoV-2 , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Imunoensaio/métodos , Anticorpos Antivirais , Peptídeos , Técnicas Eletroquímicas/métodos
4.
Planta ; 257(2): 31, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36602606

RESUMO

MAIN CONCLUSION: Molecular studies have elucidated Trichoderma's biocontrol mechanisms. Since fungicides have limited use, Trichoderma could control disease by new metabolic routes and epigenetic alterations. Due to environmental and health hazards, agrochemicals have been a concern since they were introduced in agriculture. Trichoderma, a well-known fungal genus with different mechanisms of action, is an alternative to pesticides and a great tool to help minimize disease incidence. Trichoderma-treated plants mainly benefit from disease control and growth promotion through priming, and these fungi can modulate plants' gene expression by boosting their immune system, accelerating their response to threats, and building stress tolerance. The latest studies suggest that epigenetics is required for plant priming and could be essential for growth promotion, expanding the possibilities for producing new resistant plant varieties. Trichoderma's propagules can be mass produced and formulated depending on the delivery method. Microsclerotia-based bioproducts could be a promising way of increasing the reliability and durability of marketed products in the field, as well as help guarantee longer shelf life. Developing novel formulations and selecting efficient Trichoderma strains can be tiresome, but patent search indicates an increase in the industrialization and commercialization of technologies and an expansion of companies' involvement in research and development in this field. Although Trichoderma is considered a well-known fungal genus, it still attracts the attention of large companies, universities, and research institutes around the world.


Assuntos
Micoses , Trichoderma , Trichoderma/genética , Reprodutibilidade dos Testes , Plantas/microbiologia , Agricultura , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
5.
Biosensors (Basel) ; 12(10)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36291021

RESUMO

The development of immunosensors to detect antibodies or antigens has stood out in the face of traditional methods for diagnosing emerging diseases such as the one caused by the SARS-CoV-2 virus. The present study reports the construction of a simplified electrochemical immunosensor using a graphene-binding peptide applied as a recognition site to detect SARS-CoV-2 antibodies. A screen-printed electrode was used for sensor preparation by adding a solution of peptide and reduced graphene oxide (rGO). The peptide-rGO suspension was characterized by scanning electron microscopy (SEM), Raman spectroscopy, and Fourier transform infrared spectroscopy (FT-IR). The electrochemical characterization (electrochemical impedance spectroscopy-EIS, cyclic voltammetry-CV and differential pulse voltammetry-DPV) was performed on the modified electrode. The immunosensor response is based on the decrease in the faradaic signal of an electrochemical probe resulting from immunocomplex formation. Using the best set of experimental conditions, the analytic curve obtained showed a good linear regression (r2 = 0.913) and a limit of detection (LOD) of 0.77 µg mL-1 for antibody detection. The CV and EIS results proved the efficiency of device assembly. The high selectivity of the platform, which can be attributed to the peptide, was demonstrated by the decrease in the current percentage for samples with antibody against the SARS-CoV-2 S protein and the increase in the other antibodies tested. Additionally, the DPV measurements showed a clearly distinguishable response in assays against human serum samples, with sera with a response above 95% being considered negative, whereas responses below this value were considered positive. The diagnostic platform developed with specific peptides is promising and has the potential for application in the diagnosis of other infections that lead to high antibody titers.


Assuntos
Técnicas Biossensoriais , COVID-19 , Grafite , Humanos , Grafite/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , SARS-CoV-2 , Espectroscopia de Infravermelho com Transformada de Fourier , Imunoensaio , COVID-19/diagnóstico , Eletrodos , Limite de Detecção , Peptídeos
6.
Crit Rev Food Sci Nutr ; 62(7): 1870-1889, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33207956

RESUMO

The emergence of next-generation sequencing (NGS) technologies has revolutionized the way to investigate the microbial diversity in traditional fermentations. In the field of food microbial ecology, different NGS platforms have been used for community analysis, including 454 pyrosequencing from Roche, Illumina's instruments and Thermo Fisher's SOLiD/Ion Torrent sequencers. These recent platforms generate information about millions of rDNA amplicons in a single running, enabling accurate phylogenetic resolution of microbial taxa. This review provides a comprehensive overview of the application of NGS for microbiome analysis of traditional fermented milk products worldwide. Fermented milk products covered in this review include kefir, buttermilk, koumiss, dahi, kurut, airag, tarag, khoormog, lait caillé, and suero costeño. Lactobacillus-mainly represented by Lb. helveticus, Lb. kefiranofaciens, and Lb. delbrueckii-is the most important and frequent genus with 51 reported species. In general, dominant species detected by culturing were also identified by NGS. However, NGS studies have revealed a more complex bacterial diversity, with estimated 400-600 operational taxonomic units, comprising uncultivable microorganisms, sub-dominant populations, and late-growing species. This review explores the importance of these discoveries and address related topics on workflow, NGS platforms, and knowledge bioinformatics devoted to fermented milk products. The knowledge that has been gained is vital in improving the monitoring, manipulation, and safety of these traditional fermented foods.


Assuntos
Produtos Fermentados do Leite , Bactérias/genética , Produtos Fermentados do Leite/microbiologia , Fermentação , Sequenciamento de Nucleotídeos em Larga Escala , Lactobacillus , Filogenia
7.
Enzyme Microb Technol ; 149: 109836, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34311881

RESUMO

Complex carbohydrates, proteins, and other food components require a longer digestion process to be absorbed by the lining of the alimentary canal. In addition to the enzymes of the gastrointestinal tract, gut microbiota, comprising a large range of bacteria and fungi, has complementary action on the production of digestive enzymes. Within this universe of "hidden soldiers", lactobacilli are extensively studied because of their ability to produce lactase, proteases, peptidases, fructanases, amylases, bile salt hydrolases, phytases, and esterases. The administration of living lactobacilli cells has been shown to increase nutrient digestibility. However, it is still little known how these microbial-derived enzymes act in the human body. Enzyme secretion may be affected by variations in temperature, pH, and other extreme conditions faced by the bacterial cells in the human body. Besides, lactobacilli administration cannot itself be considered the only factor interfering with enzyme secretion, human diet (microbial substrate) being determinant in their metabolism. This review highlights the potential of lactobacilli to release functional enzymes associated with the digestive process and how this complex metabolism can be explored to contribute to the human diet. Enzymatic activity of lactobacilli is exerted in a strain-dependent manner, i.e., within the same lactobacilli species, there are different enzyme contents, leading to a large variety of enzymatic activities. Thus, we report current methods to select the most promising lactobacilli strains as sources of bioactive enzymes. Finally, a patent landscape and commercial products are described to provide the state of art of the transfer of knowledge from the scientific sphere to the industrial application.


Assuntos
6-Fitase , Lactobacillus , Bactérias , Digestão , Trato Gastrointestinal , Humanos
8.
World J Microbiol Biotechnol ; 37(7): 118, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34131809

RESUMO

This review provides an overview of the application of next-generation sequencing (NGS) technologies for microbiome analysis of cocoa beans fermentation. The cocoa-producing regions where NGS has been applied include Brazil, Ghana, Ivory Coast, Cameroon, Nicaragua, and Colombia. The data collected were processed by principal component analysis (PCA) and Venn diagrams to perform a multivariate association between microbial diversity and cocoa-producing regions. NGS studies have confirmed the dominance of three major microbial groups revealed by culture-dependent approaches, i.e., lactic acid bacteria, acetic acid bacteria, and yeasts. However, a more complex microbial diversity has been revealed, comprising sub-dominant populations, late-growing species, and uncultivable microorganisms. A total of 99 microbial genera and species were for the first time reported in cocoa beans fermentation, such as Brevibacillus sp., Halomonas meridiana, Methylobacterium sp., Novosphingobium sp., and Paenibacillus pabuli. PCA and Venn diagrams showed that species composition is rarely fixed and often experiences fluctuations of varying degrees and at varying frequencies between different cocoa-producing regions. Understanding these differences will provide further directions for exploring the functional and metabolic activity of rare and abundant taxa, as well as their use as starter cultures to obtain high-quality cocoa beans.


Assuntos
Bactérias/classificação , Cacau/microbiologia , Análise de Sequência de DNA/métodos , Leveduras/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , DNA Bacteriano/genética , DNA Fúngico/genética , Fermentação , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Leveduras/genética , Leveduras/isolamento & purificação , Leveduras/fisiologia
9.
Bioresour Technol ; 330: 124888, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33713945

RESUMO

The aim of this study was to develop optimized enzyme cocktails, containing native and recombinant purified enzymes from five fungal species, for the saccharification of alkali- and acid-pretreated sugarcane bagasse (SCB), soybean hulls (SBH) and oil palm empty fruit bunches (EFB). Basic cellulases were represented by cellobiohydrolase I (CBH) and endo-glucanase II (EG) from Penicillium verruculosum and ß-glucosidase (BG) from Aspergillus niger. Auxiliary enzymes were represented by endo-xylanase A (Xyl), pectin lyase (PNL) and arabinoxylanhydrolase (AXH) from Penicillium canescens, ß-xylosidase (BX) from Aspergillus japonicus, endo-arabinase (ABN) from A. niger and arabinofuranosidase (Abf) from Aspergillus foetidus. Enzyme loads were 5 mg protein/g dry substrate (basic cellulases) and 1 mg/g (each auxiliary enzyme). The best choice for SCB and EFB saccharification was alkaline pretreatment and addition of Xyl + BX, AXH + BX or ABN + BX + Abf to basic cellulases. For SBH, acid pretreatment and basic cellulases combined with ABN + BX + Abf or Xyl + BX performed better than other enzyme preparations.


Assuntos
Penicillium , Aspergillus , Hidrólise , Resíduos Industriais , Talaromyces
10.
Bioresour Technol ; 309: 123295, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32299050

RESUMO

The aim of this work was to develop a new production, recovery and formulation process of gibberellic acid (GA3). Low-cost byproducts - citrus pulp (CP) and soybean hulls (SH) - were employed as substrate for GA3 production by Gibberella fujikuroi in semisolid fermentation. A CP/SH mixture (70%/30%) promoted high productivities both in bubble column reactor (1.66 mg L/h), and in stirred tank reactor (2.13 mg L/h). GA3 production medium cost (US$ 6.70/m3) was reduced by 85% when compared to previously reported synthetic media (US$ 44.96/m3). It was described that GA3 fermented extract has low stability, and that liquid and powder formulation of the fermented extract maintained the biomolecule activity over 6 months. Alginate and alginate/kefiran beads containing GA3 showed encapsulation efficiency of 70% and 60%, respectively. This work supports good perspectives for GA3 production using cheap substrates and simple formulation of clarified extract to favour its use in agricultural countries.


Assuntos
Reatores Biológicos , Gibberella , Fermentação , Giberelinas
11.
Planta ; 251(3): 70, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32086615

RESUMO

MAIN CONCLUSION: Lipopeptides could help to overcome a large concern in agriculture: resistance against chemical pesticides. These molecules have activity against various phytopathogens and a potential to be transformed by genetic engineering. The exponential rise of pest resistances to different chemical pesticides and the global appeal of consumers for a sustainable agriculture and healthy nutrition have led to the search of new solutions for pest control. Furthermore, new laws require a different stance of producers. Based on that, bacteria of the genus Bacillus present a great agricultural potential, producing lipopeptides (LPs) that have high activity against insects, mites, nematodes, and/or phytopathogens that are harmful to plant cultures. Biopesticide activity can be found mainly in three families of Bacillus lipopeptides: surfactin, iturin, and fengycin. These molecules have an amphiphilic nature, interfering with biological membrane structures. Their antimicrobial properties include activity against bacteria, fungi, oomycetes, and viruses. Recent studies also highlight the ability of these compounds to stimulate defense mechanisms of plants and biofilm formation, which is a key factor for the successful colonization of biocontrol organisms. The use of molecular biology has also recently been researched for continuous advances and discoveries of new LPs, avoiding possible future problems of resistance against these molecules. As a consequence of the properties and possibilities of LPs, numerous studies and developments as well as the attention of large companies in the field is expected in the near future.


Assuntos
Agricultura , Bacillus/metabolismo , Lipopeptídeos/farmacologia , Controle Biológico de Vetores/métodos , Animais , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Resistência a Medicamentos , Fungos/efeitos dos fármacos , Insetos/efeitos dos fármacos , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Ácaros/efeitos dos fármacos , Nematoides/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Praguicidas/farmacologia , Doenças das Plantas/prevenção & controle , Plantas/microbiologia , Vírus/efeitos dos fármacos
12.
Appl Biochem Biotechnol ; 191(3): 1271-1279, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32086704

RESUMO

New studies on cellulolytic enzymes aiming to improve biofuels production lead to a concern over the assaying methods commonly applied to measure their activity. One of the most used methods is Ghose's cellulase and endoglucanase assay, developed by the International Union of Pure and Applied Chemistry in 1987. Carrying out this method demands high volumes of reagents and generation of high amounts of chemical residues. This work aimed to adapt Ghose's methodology to reduce its application cost and residue generation and validate the adjustments. To do so, International and Brazilian laws were applied to validate methodologies. Method's modifications were successfully validated according to all institutions and were considered linear, accurate, precise, and reproducible. It was possible to reduce the volume of reagents and residues in 12 times. Considering the routine work of most laboratories, it is a great reduction on material costs and residue treatment, which reflects in sustainability and environmental impacts.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Celulase/química , Celulose/química , Técnicas de Química Analítica/normas , Biotecnologia/normas , Brasil , Calibragem , Técnicas de Química Analítica/métodos , Fermentação , Glucose/química , Hidrólise , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Açúcares/química
13.
Sci Rep ; 9(1): 8794, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217528

RESUMO

In Colombia, coffee growers use a traditional method of fermentation to remove the cherry pulp surrounding the beans. This process has a great influence on sensory quality and prestige of Colombian coffee in international markets, but has never been studied. Here we use an Illumina-based amplicon sequencing to investigate bacterial and fungal communities associated with spontaneous coffee-bean fermentation in Colombia. Microbial-derived metabolites were further analysed by high-performance liquid chromatography and gas chromatography-mass spectrometry. Highly diverse bacterial groups, comprising 160 genera belonging to 10 phyla, were found. Lactic acid bacteria (LAB), mainly represented by the genera Leuconostoc and Lactobacillus, showed relative prevalence over 60% at all sampling times. The structure of the fungal community was more homogeneous, with Pichia nakasei dominating throughout the fermentation process. Lactic acid and acetaldehyde were the major end-metabolites produced by LAB and Pichia, respectively. In addition, 20 volatile compounds were produced, comprising alcohols, organic acids, aldehydes, esters, terpenes, phenols, and hydrocarbons. Interestingly, 56 microbial genera, associated with native soil, seawater, plants, insects, and human contact, were detected for the first time in coffee fermentation. These microbial groups harbour a remarkable phenotypic diversity and may impart flavours that yield clues to the terroir of Colombian coffees.


Assuntos
Bactérias/crescimento & desenvolvimento , Café/microbiologia , Fermentação , Fungos/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Bactérias/genética , Colômbia , Fungos/genética , Concentração de Íons de Hidrogênio , Metaboloma , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Açúcares/análise , Temperatura , Compostos Orgânicos Voláteis/análise
14.
Waste Manag ; 90: 72-83, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31088675

RESUMO

Cocoa beans provide raw materials for global food industries valued in excess of $47 billion in world exportations. Through on-farm processing, about 80% of cocoa fruit is discarded as residual biomass, including cocoa pod husks, cocoa bean shells and cocoa sweatings. Farmers routinely discard these residues/by-products during the initial cocoa bean processing steps, occupying vast areas and raising social and environmental concerns. Alternatively, this residual biomass is used as cocoa tree fertilizer. However, its disposal is performed without proper treatment, resulting in putrid odors and plant diseases. Recently, some studies have reported the use of cocoa by-products in the production of high-value-adding molecules with potential applications in the food, pharmaceutical and cosmetic industries. In this aspect, biotechnological approaches have been shown to be a viable alternative for the transformation of this residual biomass into fine products. This article reviews the biotechnological approaches implemented for the management and exploitation of cocoa by-product. Related topics on cocoa production and residual biomass generation, sustainability and valorization of cocoa chain are addressed and discussed.


Assuntos
Cacau , Biomassa , Biotecnologia , Indústria Alimentícia , Frutas
15.
Food Chem ; 272: 441-452, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309567

RESUMO

The aim of this review is to describe the volatile aroma compounds of green coffee beans and evaluate sources of variation in the formation and development of coffee aroma through postharvest processing. The findings of this survey showed that the volatile constituents of green coffee beans (e.g., alcohols, aldehydes, and alkanes) have no significant influence on the final coffee aroma composition, as only a few such compounds remain in the beans after roasting. On the other hand, microbial-derived, odor-active compounds produced during removal of the fruit mucilage layer, including esters, higher alcohols, aldehydes, and ketones, can be detected in the final coffee product. Many postharvest processing including drying and storage processes could influence the levels of coffee aroma compositions, which remain to be elucidated. Better understanding of the effect of these processes on coffee aroma composition would assist coffee producers in the optimal selection of postharvest parameters that favor the consistent production of flavorful coffee beans.


Assuntos
Café/química , Manipulação de Alimentos/métodos , Compostos Orgânicos Voláteis/análise , Aldeídos/química , Aldeídos/isolamento & purificação , Café/metabolismo , Culinária/métodos , Armazenamento de Alimentos/métodos , Cetonas/química , Cetonas/isolamento & purificação , Mucilagem Vegetal/química , Mucilagem Vegetal/isolamento & purificação , Compostos Orgânicos Voláteis/química
16.
Bioresour Technol ; 273: 103-113, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30419445

RESUMO

An environmental friendly process was developed to produce Arthrospira maxima's biomass from sugarcane vinasse, which was generated in a bioethanol production chain, at laboratory and pilot scale. Peptides fractions were than obtained from enzymatically hydrolyzed biomass. High microalgae biomass productivities were reached (0.150 g L-1 day-1) coupled with a significant reduction of BOD and COD (89.2 and 81%, respectively). Three peptide fractions were obtained from microalgae biomass through single or sequential enzymatic hydrolysis. Antioxidant, antimicrobial, anti-inflammatory, and/or anti-collagenase activities of biopetides' fractions were observed. The PHS showed multi-biological activities. The three peptides fractions could be potential candidates for different applications in pharmaceutical, cosmetic and food industry.


Assuntos
Produtos Biológicos/metabolismo , Biomassa , Microalgas/metabolismo , Biossíntese Peptídica , Peptídeos/metabolismo , Saccharum/metabolismo , Spirulina/metabolismo , Projetos Piloto
17.
Planta ; 248(5): 1049-1062, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30069731

RESUMO

MAIN CONCLUSION: Gibberellic acid is a plant growth hormone that promotes cell expansion and division. Studies have aimed at optimizing and reducing production costs, which could make its application economically viable for different cultivars. Gibberellins consist of a large family of plant growth hormones discovered in the 1930s, which are synthesized via the terpenes route from the geranylgeranyl diphosphate and feature a basic structure formed by an ent-gibberellane tetracyclic skeleton. Among them, only four have biological activity, including gibberellic acid (GA3), which acts as a natural plant growth regulator, especially for stem elongation, seed germination, and increased fruit size. It can be obtained from plants, fungi, and bacteria. There are also some reports about microalgae GA3 producers. Fungi, especially Gibberella fujikuroi, are preferred for GA3 production via submerged fermentation or solid-state fermentation. Many factors may affect its production, some of which are related to the control and scale-up of fermentation parameters. Different GA3 products are available on the market. They can be found in liquid or solid formulations containing only GA3 or a mixture of other biological active gibberellins, which can be applied on a wide variety of cultivars, including crops and fruits. However, the product's cost still limits its large and continuous application. New low-cost and efficient GA3 production alternatives are surely welcome. This review deals with the latest scientific and technological advances on production, recovery, formulation, and applications of this important plant growth hormone.


Assuntos
Giberelinas/síntese química , Reguladores de Crescimento de Plantas/síntese química , Biotecnologia/métodos , Fermentação , Giberelinas/química , Giberelinas/isolamento & purificação , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação
18.
Biomed Res Int ; 2017: 5191046, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29082248

RESUMO

Gibberellic acid (GA3) is an important phytohormone, a member of gibberellins family, which acts as a promoter and regulator of plant growth. This study aimed to evaluate GA3 production by Fusarium moniliforme LPB03 and Gibberella fujikuroi LPB06 using different techniques of fermentation, solid state fermentation (SSF), submerged fermentation (SmF), and semisolid state fermentation (SSSF), and different types of bioreactors. In all techniques, citric pulp (CP), a subproduct obtained from the extraction of orange juice, was employed as the substrate/support. GA3 production by SSF reached 7.60 g kg-1 and 7.34 g kg-1 in Erlenmeyer flasks and column bioreactors, respectively. For SmF, the highest concentration of GA3 obtained was 236.00 mg L-1 in Erlenmeyer flasks, 273.00 mg L-1 in a 10 L stirred tank reactor (STR), and 203.00 mg L-1 in a 1.5 L bubble column reactor (BCR). SSSF was conducted with a CP suspension. In this case, GA3 concentration reached 331.00 mg L-1 in Erlenmeyer flasks and 208 mg L-1 in a BCR. The choice of the fermentation technique is undoubtedly linked to the characteristics and productivity of each process. The methods studied are inexpensive and were found to produce good proportions of GA3, making them suitable for several applications.


Assuntos
Ácido Cítrico/química , Fermentação , Giberelinas/biossíntese , Reguladores de Crescimento de Plantas/biossíntese , Reatores Biológicos , Fusarium/química , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Gibberella/química , Gibberella/genética , Gibberella/crescimento & desenvolvimento , Giberelinas/química , Giberelinas/genética , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/genética
19.
Colloids Surf B Biointerfaces ; 145: 706-715, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27289312

RESUMO

Ciprofloxacin is a broad-spectrum antibiotic associated with gastric and intestinal side effects after extended oral administration. Alginate is a biopolymer commonly employed in gel synthesis by ionotropic gelation, but unstable in the presence of biological metal-chelating compounds and/or under dried conditions. Kefiran is a microbial biopolymer able to form gels with the advantage of displaying antimicrobial activity. In the present study, kefiran-alginate gel microspheres were developed to encapsulate ciprofloxacin for antimicrobial controlled release and enhanced bactericidal effect against common pathogens. Scanning electron microscopy (SEM) analysis of the hybrid gel microspheres showed a spherical structure with a smoother surface compared to alginate gel matrices. In vitro release of ciprofloxacin from kefiran-alginate microspheres was less than 3.0% and 5.0% at pH 1.2 (stomach), and 5.0% and 25.0% at pH 7.4 (intestine) in 3 and 21h, respectively. Fourier transform infrared spectroscopy (FTIR) of ciprofloxacin-kefiran showed the displacement of typical bands of ciprofloxacin and kefiran, suggesting a cooperative interaction by hydrogen bridges between both molecules. Additionally, the thermal analysis of ciprofloxacin-kefiran showed a protective effect of the biopolymer against ciprofloxacin degradation at high temperatures. Finally, antimicrobial assays of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhymurium, and Staphylococcus aureus demonstrated the synergic effect between ciprofloxacin and kefiran against the tested microorganisms.


Assuntos
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Microesferas , Polissacarídeos/química , Administração Oral , Sistemas de Liberação de Medicamentos , Escherichia coli/efeitos dos fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Klebsiella pneumoniae/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
20.
Food Sci Technol Int ; 22(8): 732-742, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27118768

RESUMO

The aim of this work was to study the fermentation process of honey with kefir grains through a comprehensive understanding of its rheological properties, probiotic cell viability, instrumental color parameters and kinetic aspects in a batch bioreactor and during storage. The results showed that kefir grains were well adapted to bioreactor conditions, reaching high levels of cell viability (over 106 CFU mL-1 for total yeast and bacteria), phenolic compounds content (190 GAE/100 g) and acidification after 24 h of fermentation at 30 ℃. Colorimetric analysis showed that lightness (L*) and redness (a*) remained constant, while yellowness intensities (b*) decreased during fermentation time. After 35 days of storage, honey kefir beverage maintained its chemical characteristics and microbial viability as required to be classified as a probiotic product. The Ostwald-de-Waele (R2 ≥ 0.98) and Herschel-Bulkley (R2 ≥ 0.99) models can be used to predict the behavior of honey kefir beverage. The parameters analyzed in this study should be taken into account for industrial production of this novel non-dairy beverage.


Assuntos
Bebidas/microbiologia , Fermentação , Armazenamento de Alimentos , Mel/microbiologia , Kefir/microbiologia , Probióticos/análise , Manipulação de Alimentos , Viabilidade Microbiana , Nitrogênio/química , Paladar
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