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1.
Microorganisms ; 12(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38792761

RESUMO

The competitive colonization of bacteria on similar ecological niches has a significant impact during their establishment. The synthesis speeds of different chemical classes of molecules during early competitive colonization can reduce the number of competitors through metabolic effects. In this work, we demonstrate for the first time that Kosakonia cowanii Cp1 previously isolated from the seeds of Capsicum pubescens R. P. produced volatile organic compounds (VOCs) during competitive colonization against Pectobacterium aroidearum SM2, affecting soft rot symptoms in serrano chili (Capsicum annuum L.). The pathogen P. aroidearum SM2 was isolated from the fruits of C. annuum var. Serrano with soft rot symptoms. The genome of the SM2 strain carries a 5,037,920 bp chromosome with 51.46% G + C content and 4925 predicted protein-coding genes. It presents 12 genes encoding plant-cell-wall-degrading enzymes (PCDEWs), 139 genes involved in five types of secretion systems, and 16 genes related to invasion motility. Pathogenic essays showed soft rot symptoms in the fruits of C. annuum L., Solanum lycopersicum, and Physalis philadelphica and the tubers of Solanum tuberosum. During the growth phases of K. cowanii Cp1, a mix of VOCs was identified by means of HS-SPME-GC-MS. Of these compounds, 2,5-dimethyl-pyrazine showed bactericidal effects and synergy with acetoin during the competitive colonization of K. cowanii Cp1 to completely reduce soft rot symptoms. This work provides novel evidence grounding a better understanding of bacterial interactions during competitive colonization on plant tissue, where VOC synthesis is essential and has a high potential capacity to control pathogenic microorganisms in agricultural systems.

2.
Foods ; 13(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38672881

RESUMO

Quercetin (Q) dietary supplements exhibit poor oral bioavailability because of degradation throughout gastrointestinal digestion (GD), which may be overcome using mesoporous silica particles (MSPs) as an oral delivery system (ODS). This study aimed to elucidate the effect of the functionalization of MSPs with amine-(A-MSP), carboxyl-(C-MSP), or thiol-(T-MSP) groups on their efficiency as a quercetin ODS (QODS). The type and degree of functionalization (DF) were used as factors in an experimental design. The Q-loaded F-MSP (F-MSP/Q) was characterized by gas physisorption analysis, loading capacity (LC), and dynamic light scattering and kinetics of Q release at gastric and intestinal pHs. Antioxidant capacity and Q concentration of media containing F-MSP/Q were evaluated after simulated GD. A-MSP showed the highest LC (19.79 ± 2.42%). C-MSP showed the lowest particle size at pH 1.5 or 7.4 (≈200 nm). T-MSP exhibited the maximum Q release at pH 7.4 (11.43%). High DF of A-MSP increased Q retention, regardless of pH. A-MSP preserved antioxidant capacity of Q-released gastric media (58.95 ± 3.34%). Nonetheless, MSP and F-MSP did not protect antioxidant properties of Q released in intestinal conditions. C-MSP and T-MSP showed essential features for cellular uptake and Q release within cells that need to be assessed.

3.
Antibiotics (Basel) ; 13(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38391568

RESUMO

Chili powder is an important condiment around the world. However, according to various reports, the presence of pathogenic microorganisms could present a public health risk factor during its consumption. Therefore, microbiological quality assessment is required to understand key microbial functional traits, such as antibiotic resistance genes (ARGs). In this study, metagenomic next-generation sequencing (mNGS) and bioinformatics analysis were used to characterize the comprehensive profiles of the bacterial community and antibiotic resistance genes (ARGs) in 15 chili powder samples from different regions of Mexico. The initial bacterial load showed aerobic mesophilic bacteria (AMB) ranging between 6 × 103 and 7 × 108 CFU/g, sporulated mesophilic bacteria (SMB) from 4.3 × 103 to 2 × 109 CFU/g, and enterobacteria (En) from <100 to 2.3 × 106 CFU/g. The most representative families in the samples were Bacillaceae and Enterobacteriaceae, in which 18 potential pathogen-associated species were detected. In total, the resistome profile in the chili powder contained 68 unique genes, which conferred antibiotic resistance distributed in 13 different classes. Among the main classes of antibiotic resistance genes with a high abundance in almost all the samples were those related to multidrug, tetracycline, beta-lactam, aminoglycoside, and phenicol resistance. Our findings reveal the utility of mNGS in elucidating microbiological quality in chili powder to reduce the public health risks and the spread of potential pathogens with antibiotic resistance mechanisms.

4.
Foods ; 13(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397576

RESUMO

Electrostatic fermentation avoids the cellular redox imbalance of traditional fermentation, but knowledge gaps exist. This study explores the impact of electrostatic fermentation on the growth, volatile profile, and genetic response of Saccharomyces pastorianus Saflager S-23. The applied voltage (15 and 30 V) in the electrostatic fermentation system increased the growth and substrate utilization of S. pastorianus while decreasing ethanol production. The aromas typically associated with traditional fermentation, such as alcoholic, grape, apple, and sweet notes, were diminished, while aromas like roses, fruits, flowers, and bananas were augmented in electrostatic fermentation. RNA-seq analysis revealed upregulation of genes involved in cell wall structure, oxidoreductase activity, and iron ion binding, while genes associated with protein synthesis, growth control, homeostasis, and membrane function were downregulated under the influence of applied voltage. The electrostatic fermentation system modulates genetic responses and metabolic pathways in yeast, rendering it a promising method for tailored beer production. Demonstrating feasibility under industrial-scale and realistic conditions is crucial for advancing towards commercialization.

5.
Microorganisms ; 11(10)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37894149

RESUMO

The Kosakonia cowanii Cp1 strain was isolated from seeds of Capsicum pubescens R. & P. cultivated in Michoacan, Mexico. Genetic and ecological role analyses were conducted for better characterization. The results show that genome has a length of 4.7 Mbp with 56.22% G + C and an IncF plasmid of 128 Kbp with 52.51% G + C. Furthermore, pathogenicity test revealed nonpathogenic traits confirmed by the absence of specific virulence-related genes. Interestingly, when fungal inhibitory essays were carried out, the bacterial synthesis of volatile organic compounds (VOCs) with antifungal activity showed that Sclerotinia sp. and Rhizoctonia solani were inhibited by 87.45% and 77.24%, respectively. Meanwhile, Sclerotium rolfsii, Alternaria alternata, and Colletotrichum gloeosporioides demonstrated a mean radial growth inhibition of 52.79%, 40.82%, and 55.40%, respectively. The lowest inhibition was by Fusarium oxysporum, with 10.64%. The VOCs' characterization by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) revealed 65 potential compounds. Some of the compounds identified with high relative abundance were ketones (22.47%), represented by 2-butanone, 3-hydroxy (13.52%), and alcohols (23.5%), represented by ethanol (5.56%) and 1-butanol-3-methyl (4.83%). Our findings revealed, for the first time, that K. cowanii Cp1 associated with C. pubescens seeds possesses potential traits indicating that it could serve as an effective biocontrol.

6.
Plants (Basel) ; 12(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37896019

RESUMO

For the management of Spodoptera frugiperda, botanical extracts have been used to reduce the environmental impacts of synthetic chemical pesticides. In the present investigation, the insecticidal activity of the acetonic and methanolic extracts of Heterotheca inuloides (Asteraceae) and of the main compound 7-hydroxy-3,4-dihydrocadalene on this pest as well as its ecotoxicological effect on Poecilia reticulata were evaluated. A greater insecticidal response was obtained from the acetonic extracts than from the methanolic extracts, with LC50 values of 730.4 ppm and 711.7 ppm for samples 1 and 2, respectively. Similarly, there was a lethal effect on 50% of the P. reticulata population at low concentrations in the acetonic extract compared to the methanolic extract. The sesquiterpene 7-hydroxy-3,4-dihydrocadalene has greater insecticidal activity by presenting an LC50 of 44.36 ppm; however, it is classified as moderately toxic for guppy fish.

7.
Microorganisms ; 11(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37512930

RESUMO

Kosakonia cowanii strain Ch1 was isolated from Mexican chili powder, and the genome was sequenced. The genome was 4,765,544 bp in length, with an average G + C content of 56.22%, and a plasmid (pCh1) of 128,063 bp with an average G + C content of 52.50%. A phylogenetic analysis revealed a close relation with pathogenic strains; nevertheless, some virulence-related genes were absent, and this genetic characteristic may explain the fact that K. cowanii Ch1 behaved as a non-pathogenic strain when infection assays were performed on the leaves and fruits of Capsicum annuum L. Surprisingly, we observed that this bacterial strain had the ability to spread throughout serrano pepper seeds. Furthermore, K. cowanii Ch1 was evaluated for the production of volatile organic compounds (VOCs) against fungal pathogens, and the results showed that Alternaria alternata and Sclerotium rolfsii were inhibited in a radial mycelial growth assay by a mean rate of 70% and 64%, while Fusarium oxysporum was inhibited by only approximately 10%. Based on the headspace solid-phase microextraction combined with the gas chromatography mass spectrometry (HS-SPME-GC-MS), 67 potential VOCs were identified during the fermentation of K. cowanii Ch1 in TSA medium. From these VOCs, nine main compounds were identified based on relative peak area: dodecanoic acid; 3-hydroxy ethanol; 1-butanol-3-methyl; acetaldehyde; butanoic acid, butyl ester; cyclodecane; 2-butanone, 3-hydroxy; disulfide, dimethyl and pyrazine-2,5-dimethyl. Our findings show the potential of K. cowanii Ch1 for the biocontrol of fungal pathogens through VOCs production and reveal additional abilities and metabolic features as beneficial bacterial specie.

8.
Polymers (Basel) ; 15(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36987186

RESUMO

Sargassum spp. affects the Caribbean shores; thus, its remotion or valorization is a priority. This work aimed to synthesize a low-cost magnetically retrievable Hg+2 adsorbent functionalized with ethylenediaminetetraacetic acid (EDTA) based on Sargassum. The Sargassum was solubilized to synthesize by co-precipitation a magnetic composite. A central composite design was assessed to maximize the adsorption of Hg+2. The solids yield magnetically attracted mass, and the saturation magnetizations of the functionalized composite were 60.1 ± 17.2%, 75.9 ± 6.6%, and 1.4 emu g-1. The functionalized magnetic composite yielded 29.8 ± 0.75 mg Hg+2 g-1 of chemisorption after 12 h, pH 5, and 25 °C achieving 75% Hg+2 adsorption after four reuse cycles. Crosslinking and functionalization with Fe3O4 and EDTA created differences in surface roughness as well as the thermal events of the composites. The Fe3O4@Sargassum@EDTA composite was a magnetically recovered biosorbent of Hg2+.

9.
World J Hepatol ; 14(8): 1678-1686, 2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36157873

RESUMO

BACKGROUND: The global coronavirus disease 2019 (COVID-19) pandemic has caused more than 5 million deaths. Multiorganic involvement is well described, including liver disease. In patients with critical COVID-19, a new entity called "post-COVID-19 cholangiopathy" has been described. CASE SUMMARY: Here, we present three patients with severe COVID-19 that subsequently developed persistent cholestasis and chronic liver disease. All three patients required intensive care unit admission, mechanical ventilation, vasopressor support, and broad spectrum antibiotics due to secondary infections. Liver transplant protocol was started for two of the three patients. CONCLUSION: Severe COVID-19 infection should be considered a potential risk factor for chronic liver disease and liver transplantation.

10.
Parasitol Res ; 121(5): 1407-1417, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35106653

RESUMO

Avian haemosporidians from the genera Plasmodium and Haemoproteus are vector transmitted parasites. A growing body of evidence suggests that variation in their prevalence within avian communities is correlated with a variety of avian ecological traits. Here, we examine the relationship between infection probability and diversity of haemosporidian lineages and avian host ecological traits (average body mass, foraging stratum, migratory behavior, and nest type). We used molecular methods to detect haemosporidian parasites in blood samples from 642 individual birds of 149 species surveyed at four localities in the Brazilian Pantanal. Based on cytochrome b sequences, we recovered 28 lineages of Plasmodium and 17 of Haemoproteus from 31 infected avian species. Variation in lineage diversity among bird species was not explained by avian ecological traits. Prevalence was heterogenous across avian hosts. Bird species that forage near the ground were less likely to be infected by Haemoproteus, whereas birds that build open cup nests were more likely infected by Haemoproteus. Furthermore, birds foraging in multiple strata were more likely to be infected by Plasmodium. Two other ecological traits, often related to host resistance (body mass and migratory behavior), did not predict infection probability among birds sampled in the Pantanal. Our results suggest that avian host traits are less important determinants of haemosporidian diversity in Pantanal than in other regions, but reinforces that host attributes, related to vector exposure, are to some extent important in modulating infection probability within an avian host assemblage.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Infecções Protozoárias em Animais , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Filogenia , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/epidemiologia
11.
Int J Mol Sci ; 24(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36613543

RESUMO

Beef is a fundamental part of the human diet, but it is highly susceptible to microbiological and physicochemical deterioration which decrease its shelf life. This work aimed to formulate an active edible film (AEF) incorporated with amino-functionalized mesoporous silica nanoparticles (A-MSN) loaded with Mexican oregano (Lippia graveolens Kunth) essential oil (OEO) and to evaluate its effect as a coating on fresh beef quality during refrigerated storage. The AEF was based on amaranth protein isolate (API) and chitosan (CH) (4:1, w/w), to which OEO emulsified or encapsulated in A-MSN was added. The tensile strength (36.91 ± 1.37 MPa), Young's modulus (1354.80 ± 64.6 MPa), and elongation (4.71%) parameters of AEF made it comparable with synthetic films. The antimicrobial activity of AEF against E. coli O157:H7 was improved by adding 9% (w/w) encapsulated OEO, and interactions of glycerol and A-MSN with the polymeric matrix were observed by FT-IR spectroscopy. In fresh beef, after 42 days, AEF reduced the population growth (Log CFU/cm2, relative to uncoated fresh beef) of Brochothrix thermosphacta (5.5), Escherichia coli (3.5), Pseudomonas spp. (2.8), and aerobic mesophilic bacteria (6.8). After 21 days, odor acceptability of coated fresh beef was improved, thus, enlarging the shelf life of the beef and demonstrating the preservation capacity of this film.


Assuntos
Filmes Comestíveis , Lippia , Nanopartículas , Óleos Voláteis , Origanum , Animais , Bovinos , Humanos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Origanum/química , Lippia/química , Conservação de Alimentos/métodos , Microbiologia de Alimentos , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Embalagem de Alimentos/métodos
12.
Plants (Basel) ; 10(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34579435

RESUMO

Castor bean (Ricinus communis) seeds contain ricinine, an alkaloid with insecticidal and insectistatic activities. Elicitation with salicylic acid (SA) has proven to stress R. communis and might modify the ricinine concentration. The aim of this study was to evaluate the concentration of ricinine in the bagasse of seeds from R. communis elicited with exogenous SA under greenhouse conditions. Plants were grown and divided into five groups, which were sprayed with SA and drench with 50 mL 60 days after sowing with concentrations of SA (0, 100, 300, 600 and 900 µM). Clusters were mixed and separated according to the treatment, and dried. The seeds were ground, the oil was extracted by Soxhlet with hexane, and then the bagasse was extracted with methanol. Ricinine was determined by HPLC. Elicitation did not change the plant height or diameter; the control group had 9.17 µg mL-1 of ricinine; and the concentrations followed a hormesis curve with the peak at 300 µM of SA that had a ricinine concentration of 18.25 µg mL-1. Elicitation with SA might be a cost-effective technique to increase ricinine from R. communis bagasse.

13.
Int J Emerg Med ; 14(1): 8, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472577

RESUMO

The WHO defines a possible case of COVID-19 as a person experiencing fever, cough, shortness of breath, and neurological signs including anosmia, ageusia, or dysgeusia. However, experiences from hospitals all over the world have shown that presentations vary widely. Some atypical presentations include cardiac, gastrointestinal, neurological, and cutaneous and while some are driven by the inflammatory response, others are a consequence of the hypercoagulable state. In our emergency department in a private hospital in Mexico City, we received two patients with very different symptoms on the same shift. Two previously healthy men in their 40s presented to the ER with very atypical manifestations of COVID-19. Neither of them complained of fever, cough, or shortness of breath. The first referred a 3-day history of hiccups that had not resolved with metoclopramide. The second presented with an acute episode of altered mental status. While the first case revealed lung involvement of the disease, the second case had a clean chest CT scan. These cases are relevant as manifestations of COVID-19 vary widely, especially in previously healthy young adults.

14.
Foods ; 9(11)2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33172144

RESUMO

Food packaging faces the negative impact of synthetic materials on the environment, and edible coatings offer one alternative from filmogenic suspensions (FS). In this work, an active edible FS based on chitosan (C) and quinoa protein (QP) cross-linked with transglutaminase was produced. Thyme (T) and rosemary (R) essential oils (EOs) were incorporated as antimicrobial agents. Particle size, Z potential, and rheological parameters were evaluated. The antimicrobial activity against Micrococcus luteus (NCIB 8166) and Salmonella sp. (Lignieres 1900) was monitored using atomic force microscopy and image analysis. Results indicate that EOs incorporation into C:QP suspensions did not affect the Z potential, ranging from -46.69 ± 3.19 mV to -46.21 ± 3.83 mV. However, the polydispersity index increased from 0.51 ± 0.07 to 0.80 ± 0.04 in suspensions with EO. The minimum inhibitory concentration of active suspensions against Salmonella sp. was 0.5% (v/v) for thyme and 1% (v/v) for rosemary. Entropy and fractal dimension of the images were used to confirm the antimicrobial effect of EOs, which modified the surface roughness.

15.
Appl Biochem Biotechnol ; 188(2): 395-409, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30478822

RESUMO

Enzymes are gradually increasingly preferred over chemical processes, but commercial enzyme applications remain limited due to their low stability and low product recovery, so the application of an immobilization technique is required for repeated use. The aims of this work were to produce stable enzyme complexes of cross-linked xylanase on magnetic chitosan, to describe some characteristics of these complexes, and to evaluate the thermal stability of the immobilized enzyme and its reusability. A xylanase was cross-linked to magnetite particles prepared by in situ co-precipitation of iron salts in a chitosan template. The effect of temperature, pH, kinetic parameters, and reusability on free and immobilized xylanase was evaluated. Magnetization, morphology, size, structural change, and thermal behavior of immobilized enzyme were described. 1.0 ± 0.1 µg of xylanase was immobilized per milligram of superparamagnetic chitosan nanoparticles via covalent bonds formed with genipin. Immobilized xylanase showed thermal, pH, and catalytic velocity improvement compared to the free enzyme and can be reused three times. Heterogeneous aggregates of 254 nm were obtained after enzyme immobilization. The immobilization protocol used in this work was successful in retaining enzyme thermal stability and could be important in using natural compounds such as Fe3O4@Chitosan@Xylanase in the harsh temperature condition of relevant industries.


Assuntos
Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Ascomicetos/enzimologia , Biotecnologia , Quitosana/química , Reagentes de Ligações Cruzadas , Endo-1,4-beta-Xilanases/ultraestrutura , Estabilidade Enzimática , Enzimas Imobilizadas/ultraestrutura , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/ultraestrutura , Concentração de Íons de Hidrogênio , Iridoides , Cinética , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Varredura , Temperatura
16.
Med. interna Méx ; 34(6): 924-932, nov.-dic. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-990162

RESUMO

Resumen: El advenimiento de nuevos fármacos para el tratamiento de los distintos componentes del síndrome metabólico, que por su farmacocinética y farmacodinamia tengan un efecto pleiotrópico, ha tomado auge. Hace poco los inhibidores del cotransportador sodio glucosa tipo 2 (SGLT2) prescritos para el tratamiento de la diabetes mellitus 2 han demostrado tener un efecto protector cardiorrenal. Éstos actúan en el segmento S1 del túbulo proximal disminuyendo la filtración de glucosa e incrementando su excreción urinaria; con efecto glucosúrico y natriurético. Este último es el principal mecanismo de protección cardiovascular. Modelos experimentales y estudios, entre los que destacan el estudio EMPAREG y el programa CANVAS, han demostrado que los inhibidores de SGLT2 permiten disminuir la progresión de la miocardiopatía hipertrófica, fibrosis, remodelamiento, disfunción sistólica e insuficiencia cardiaca, por su efecto en la precarga y poscarga. Los resultados de estos estudios reconocen a este grupo de fármacos (específicamente a la empagliflozina y canagliflozina) como tratamiento de protección cardiovascular en pacientes con diabetes mellitus 2, recomendados actualmente por la FDA, ACC/AHA, la Sociedad Europea de Cardiología y recientemente por la Asociación Americana de Diabetes (ADA) en su reciente publicación de 2018.


Abstract: There is an increase in the use of new drugs for the treatment of the different elements that integrate the metabolic syndrome; that, by their pharmacokinetics and pharmacodynamics have a pleiotropic effect. Recently, the inhibitors of sodium glucose cotransporter type 2 (SGLT2) used for the treatment of diabetes mellitus type 2 have demonstrated a cardio-renal protector effect. They function at the S1 segment of the proximal tube, lowering the filtration of glucose and enhancing its excretion; resulting in a glycosuric and natriuretic effect. This is the main mechanism of cardiovascular protection. Experimental essays and different studies, such as the EMAREG study and the CANVAS program, have established that the inhibitors of SGLT2 reduce the progression of hypertrophic cardiomyopathy, fibrosis, cardiac remodeling, systolic dysfunction and heart failure. The results of these studies recognize this group of drugs (empaglifozine and canaglifozine) as a valid treatment for cardiovascular protection in patients with diabetes mellitus type 2, and which is recommended by the FDA, the ACC/AHA, the European Society of Cardiology and the American Diabetes Association (ADA) in its last publication in 2018.

17.
Int J Mol Sci ; 18(11)2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29117148

RESUMO

Edible films (EFs) have gained great interest due to their ability to keep foods safe, maintaining their physical and organoleptic properties for a longer time. The aim of this work was to develop EFs based on a chitosan-zein mixture with three different essential oils (EOs) added: anise, orange, and cinnamon, and to characterize them to establish the relationship between their structural and physical properties. The addition of an EO into an EF significantly affected (p < 0.05) the a* (redness/greenness) and b* (yellowness/blueness) values of the film surface. The EFs presented a refractive index between 1.35 and 1.55, and thus are classified as transparent. The physical properties of EFs with an added EO were improved, and films that incorporated the anise EO showed significantly lower water vapor permeability (1.2 ± 0.1 g mm h-1 m-2 kPa-1) and high hardness (104.3 ± 3.22 MPa). EFs with an added EO were able to inhibit the growth of Penicillium sp. and Rhizopus sp. to a larger extent than without an EO. Films' structural changes were the result of chemical interactions among amino acid side chains from zein, glucosamine from chitosan, and cinnamaldehyde, anethole, or limonene from the EOs as detected by a Raman analysis. The incorporation of an EO in the EFs' formulation could represent an alternative use as coatings to enhance the shelf life of food products.


Assuntos
Antifúngicos/química , Quitosana/química , Embalagem de Alimentos , Óleos Voláteis/química , Zeína/química , Acroleína/análogos & derivados , Acroleína/química , Derivados de Alilbenzenos , Anisóis/química , Cicloexenos/química , Limoneno , Penicillium/efeitos dos fármacos , Polímeros/farmacologia , Refratometria , Rhizopus/efeitos dos fármacos , Propriedades de Superfície , Terpenos/química
18.
Bioresour Technol ; 212: 334-337, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27130226

RESUMO

Solid state fermentation (SSF) is used to produce industrial enzymes. The objective of this study was to use a co-culture of Aspergillus niger GS1 and Trichoderma reesei, grown on a mixture of Bermuda grass and corn cob to obtain fermented forage (FF) rich in hydrolytic enzymes, as a value added ingredient for animal feed. FPase, amylase and xylanase productivities (dry matter, DM) were 8.8, 181.4, and 42.1Ug(-1)h(-1), respectively (1U=reducing sugars released min(-1)), after 12-16h of SSF with C/N=60. Cellulose, hemicellulose and lignin decreased 1.6-, 2.7- and 1.9-fold (DM), respectively. In vitro ruminal and true digestibility of DM was improved 2.4- and 1.4-fold. Ruminal digestion of FF reduced 1.32-fold the acetate:propionate ratio, which may reduce the environmental impact of ruminants feeding. On-site hydrolytic enzymes productivity using SSF without enzymes extraction could be of economic potential for digestibility improvement in animal feed.


Assuntos
Ração Animal , Aspergillus niger/enzimologia , Cynodon , Trichoderma/enzimologia , Zea mays , Animais , Aspergillus niger/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Celulose/metabolismo , Técnicas de Cocultura , Cynodon/microbiologia , Digestão , Enzimas/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fermentação , Hidrólise , Lignina/metabolismo , Polissacarídeos/metabolismo , Ruminantes , Trichoderma/crescimento & desenvolvimento , Zea mays/microbiologia
19.
Endocrine ; 53(1): 258-70, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26767652

RESUMO

Maternal obesity during pregnancy has been related with several pathological states in offspring. However, the impact of maternal obesity on reproductive system on the progeny is beginning to be elucidated. In this work, we characterize the effect of maternal obesity on puberty onset and follicular development in adult offspring in rats. We also propose that alterations in ovarian physiology observed in offspring of obese mothers are due to increased levels of estradiol during early development. Offspring of control dams and offspring of dams exposed to a high-fat diet (HF) were studied at postnatal days (PND) 1, 7, 14, 30, 60, and 120. Body weight and onset of puberty were measured. Counting of ovarian follicles was performed at PND 60 and 120. Serum estradiol, estriol, androstenedione, FSH, LH, and insulin levels were measured by ELISA. Hepatic CYP3A2 expression was determined by Western blot. HF rats had a higher weight than controls at all ages and they also had a precocious puberty. Estradiol levels were increased while CYP3A2 expression was reduced from PND 1 until PND 60 in HF rats compared to controls. Estriol was decreased at PND60 in HF rats. Ovaries from HF rats had a decrease in antral follicles at PND60 and PND120 and an increase in follicular cysts at PND60 and PND120. In this work, we demonstrated that maternal obesity in rats alters follicular development and induces follicular cysts generation in the adult offspring. We observed that maternal obesity produces an endocrine disruption through increasing endogenous estradiol in early life. A programmed failure in hepatic metabolism of estradiol is probably the cause of its increase.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Estradiol/sangue , Fígado/metabolismo , Obesidade/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Androstenodiona/sangue , Animais , Peso Corporal/fisiologia , Dieta Hiperlipídica , Estriol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Insulina/sangue , Hormônio Luteinizante/sangue , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/sangue , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Ratos , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia
20.
Electron. j. biotechnol ; Electron. j. biotechnol;14(2): 9-9, Mar. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591939

RESUMO

Hemicellulosic agricultural by-products such as corn stover (CS) are highly available materials which represent an opportunity to develop value added products. Native Aspergillus niger GS1 was used for solid-state fermentation (SSF) on alkali pre-treated CS (ACS) aimed to optimize xylanolytic enzymes production, and their effect on in vitro ruminal and true digestibility of ACS. Enzyme production was empirically modelled using a fractional factorial design 2(9-5), and the resulting significant factors were glucose, yeast extract and two mineral salts, which were arranged in a Draper-Lin optimization design at two levels. Predicted optimum xylanolytic activity of 33.6 U (mg protein)-1 was achieved at 48 hrs of SSF, and was validated by confirmatory experiments. ACS was incubated with a semipurified enzymatic extract (EE) showing a xylanolytic activity of 1600 U kg-1 dry ACS for 12 hrs before exposure to cow's ruminal liquid for 72 hrs, which led to 5 percent and 10 percent increase of in vitro ruminal and true digestibility, respectively. CS is a readily available by-product in different regions which after alkaline treatment and partial hydrolysis with the EE, may be advantageously used as supplement for ruminant feed.


Assuntos
Animais , Ração Animal , Aspergillus niger/enzimologia , Zea mays/química , Dióxido de Carbono , Celulose/metabolismo , Digestão , Fermentação , Polissacarídeos/metabolismo , Fatores de Tempo , Xilanos/metabolismo
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