Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Biotechnol Appl Biochem ; 71(4): 753-765, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38436528

RESUMO

This study aimed to assess the technical feasibility of incorporating selenized Lactobacillus spp. microencapsulated via spray drying into cattle feed. Gum Arabic and maltodextrin were used as encapsulating agents. The encapsulation process was carried out with a drying air flow rate of 1.75 m3/min, inlet air temperature of 90°C, and outlet air temperature of 75°C. The viability of the encapsulated microorganisms and the technological characteristics of the obtained microparticles were evaluated. Microorganisms were incorporated into beef cattle feed to supplement their diet with up to 0.3 mg of Se per kilogram of feed. The encapsulated particles, consisting of a 50/50 ratio of gum Arabic/maltodextrin at a 1:20 proportion of selenized biomass to encapsulant mixture, exhibited superior technical viability for application in beef cattle feed. Supplemented feeds displayed suitable moisture, water activity, and hygroscopicity values, ensuring the preservation of viable microorganisms for up to 5 months of storage, with an approximate count of 4.5 log CFU/g. Therefore, supplementing beef cattle feed with selenized and microencapsulated lactic acid bacteria represents a viable technological alternative, contributing to increased animal protein productivity through proper nutrition.


Assuntos
Ração Animal , Suplementos Nutricionais , Secagem por Atomização , Animais , Bovinos , Ração Animal/análise , Selênio/química , Polissacarídeos/química , Lactobacillus/metabolismo , Composição de Medicamentos , Goma Arábica/química
2.
Food Technol Biotechnol ; 60(4): 449-457, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36816871

RESUMO

Research background: Cheese whey and whey permeate are dairy industry by-products usually sent to effluent treatment or incorrectly disposed in the environment, generating costs for the production of dairy products and environmental problems due to the high organic load. Cheese whey and whey permeate can be reused as wall materials to form chia oil microcapsules, which act as a barrier to prooxidants. This study aims to develop an encapsulation method by spray-drying to protect chia oil using dairy by-products as wall materials. Experimental approach: We evaluated cheese whey, whey permeate and mixtures of m(cheese whey):m(whey permeate)=50, 70 and 80% as encapsulating agents with the spray-drying process. Initially, we characterized the chia oil and encapsulating materials. Chia oil emulsions were prepared using the encapsulating materials and an emulsifier. The stability of the emulsions was evaluated by creaming index, and they were characterized according to size distribution and polydispersity index. Emulsions were encapsulated in a spray dryer with inlet and outlet air temperature at 125 and 105 °C, respectively. After encapsulation, we assessed the oxidative degradation of chia oil over 30 days of storage by determining the peroxide index. Results and conclusions: Emulsions presented creaming index between 51 and 83% in all formulations, and the oxidative stability of microencapsulated chia oil was significantly higher than that of free chia oil after 30 days. Wall material combination affected both encapsulation efficiency and oxidation protection. The cheese whey and whey permeate (8:2) mixture exhibited the highest encapsulation efficiency (70.07%) and ability to protect the chia seed oil. After 30 days, the peroxide value was below the maximum limit considered safe for human consumption. Novelty and scientific contribution: According to these results, dairy by-products can be used for encapsulation of oxidation-sensitive oils. This represents an alternative use for dairy by-products, which otherwise are discarded and can impact the environment due to their high organic load. Our findings suggest that dairy by-products can be effectively used as wall materials to generate value-added products.

3.
J Toxicol Environ Health A ; 83(8): 289-301, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32366184

RESUMO

Natural products are still a promising source of bioactive molecules. Food and Drug Administration data showed that approximately 49% of the approved molecules originate naturally or chemically-resemble these substances, of which more than 70% are being used in anticancer therapy. It is noteworthy that at present there are no scientific studies to prove the effectiveness and safety of a number of plants used in folk medicine such as in the case of Calyptranthes grandifolia O. Berg (Myrtaceae) originally from South America. The aim of the present study was to determine the biological potential and toxicological effects of the aqueous leaf extract of C. grandifolia. The main detected phytoconstituents were condensed tannins and flavonoids and a high quantity of polyphenols. Regarding the antimicrobial potential, the extract exerted inhibitory activity against Pseudomonas aeruginosa. The results also revealed the extract induced DNA damage in a concentration-dependent manner in RAW 264.7 cells. In addition, C. grandifolia produced cytotoxicity in leukemia cell lines (HL60 and Kasumi-1) without affecting isolated human lymphocytes but significantly inhibited JAK3 and p38α enzyme activity. Taken together, these findings add important information on the biological and toxicological effects of C. grandifolia, indicating that aqueous extract may be a source of natural antimicrobial and antileukemic constituents.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Myrtaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Antibacterianos/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Compostos de Bifenilo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Camundongos , Picratos , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Células RAW 264.7
4.
Inflammopharmacology ; 27(3): 433-452, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30929155

RESUMO

While the inactivation mutations that eliminate JAK3 function lead to the immunological disorders such as severe combined immunodeficiency, activation mutations, causing constitutive JAK3 signaling, are known to trigger various types of cancer or are responsible for autoimmune diseases, such as rheumatoid arthritis, psoriasis, or inflammatory bowel diseases. Treatment of hyperactivated JAK3 is still an obstacle, due to different sensibility of mutation types to conventional drugs and unwanted side effects, because these drugs are not absolutely specific for JAK3, thus inhibiting other members of the JAK family, too. Lack of information, in which way sole inhibition of JAK3 is necessary for elimination of the disease, calls for the development of isoform-specific JAK3 inhibitors. Beside this strategy, up to date peptides are a rising alternative as chemo- or immunotherapeutics, but still sparsely represented in drug development and clinical trials. Beyond a possible direct inhibition function, crossing the cancer cell membrane and interfering in disease-causing pathways or triggering apoptosis, peptides could be used in future as adjunct remedies to potentialize traditional therapy and preserve non-affected cells. To discuss such feasible topics, this review deals with the knowledge about the structure-function of JAK3 and the actual state-of-the-art of isoform-specific inhibitor development, as well as the function of currently approved drugs or those currently being tested in clinical trials. Furthermore, several strategies for the application of peptide-based drugs for cancer therapy and the physicochemical and structural relations to peptide efficacy are discussed, and an overview of peptide sequences, which were qualified for clinical trials, is given.


Assuntos
Janus Quinase 3/metabolismo , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
5.
Int J Biol Macromol ; 109: 303-310, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29258896

RESUMO

This work is the first study of the immobilization of Aspergillus oryzae ß-galactosidase (Gal) on powdered collagen (Col) that had formed a chelate with aluminum (Col-Al-Gal). Other collagen treatments, including those with acetic acid, glutaraldehyde, and a combination of aluminum and glutaraldehyde (Col-Al-Glu-Gal), were also tested. High-yield (superior to 80%) and high-efficiency (superior to 99%) immobilization was obtained for the derivatives Col-Al-Gal and Col-Al-Glu-Gal, even at high protein loads (500-1,000 mg g-1 of support). The storage stability of Gal immobilized on Col-Al and Col-Al-Glu resulted in Gal retaining approximately 60% of its initial activity after 90 days at 4 °C. The half-life values of derivatives Col-Al-Gal and Col-Al-Glu-Gal were higher than those of soluble enzyme at 65, 68, 70, and 73 °C. The derivatives Col-Al-Gal and Col-Al-Glu-Gal retained high enzyme activity in batch hydrolysis of lactose in permeate and lactose solutions for 50 and 60 cycles, respectively. Our results suggest that powdered collagen treated with aluminum, a low-cost support, is a promising support for the immobilization of ß-galactosidase.


Assuntos
Aspergillus oryzae/enzimologia , Colágeno/química , Colágeno/metabolismo , Enzimas Imobilizadas , beta-Galactosidase/química , beta-Galactosidase/metabolismo , Catálise , Quelantes , Hidrólise , Cinética , Lactose/química , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Mol Cell Biochem ; 424(1-2): 35-43, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27704465

RESUMO

Calyptranthes tricona is a species (Myrtaceae) native to South Brazil. Plants belonging to this family are folkloric used for analgesia, inflammation, and infectious diseases. However, little is known about the toxic potential of C. tricona. The present study aimed to evaluate the antioxidant activity of C. tricona ethanol and hexane leaf extracts, as well as verify their effect on human lymphocytes and MCF-7 cells. The extracts were subjected to preliminary phytochemical screening, antioxidant activity using DPPH and ORAC methods. Genotoxic and mutagenic effects in cultured human lymphocytes were assessed using the comet assay and the micronucleus assay, respectively. In addition, cell viability by MTT assay and fluorometric analysis of mitochondrial potential and caspases-9 activity were performed in order to verify the possible effects of both extracts on H2O2-induced cell death of MCF-7 cells. Our findings revealed that the phenol content and the antioxidant activity were only present in the ethanol extract. Also, the phytochemical screening presented steroids, triterpenoids, condensed tannins, and flavones as the main compounds. However, both extracts were capable of inducing concentration-dependent DNA damage in human lymphocytes. When treating MCF-7 cells with the extracts, both of them inhibited MCF-7 cell death in response to oxidative stress through a decrease of mitochondrial depolarization and caspases-9 activity. Thus, our results need to be considered in future in vitro and in vivo studies of C. tricona effects. In the meanwhile, we recommend caution in the acute/chronic use of this homemade preparation for medicinal purpose.


Assuntos
Dano ao DNA , Peróxido de Hidrogênio/farmacologia , Linfócitos/metabolismo , Myrtaceae/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Morte Celular/efeitos dos fármacos , Feminino , Humanos , Linfócitos/patologia , Células MCF-7 , Extratos Vegetais/química
7.
Biomed Pharmacother ; 84: 382-386, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27668538

RESUMO

Alzheimer's and Parkinson's diseases are neurodegenerative disorders characterized by progressive neuronal dysfunction. Previous studies revealed that some natural products have neuroprotective properties, including species of the Myrtaceae family. However, the neuromodulatory potential of Calyptranthes grandifolia is not clear. In the present study, we examined the ability of the ethanol and hexane leaf extracts of C. grandifolia to prevent 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in vitro. Initially, we investigated the potential of the extracts to inhibit the neurodegenerative-related enzymes c-Jun N-terminal kinase 3 (JNK3) and acetylcholinesterase (AChE). In addition, SH-SY5Y cell viability was assessed by MTT assay after 100µM 6-OHDA-induced cell damage. In order to verify the possible effects of both extracts on 6-OHDA-induced cell death, hydrogen peroxide generation, mitochondrial potential and caspases-3 activity were assessed. Our findings revealed that ethanol extract exhibited inhibitory activity against JNK3 and AChE. In addition, when co-treating SH-SY5Y cells with 6-OHDA and the extracts, oxidative stress was inhibited by both extracts through a decrease of mitochondrial depolarization and caspases-3 activity. In summary, ethanol and hexane extracts of C. grandifolia have some suppressive property against neurotoxicity induced by 6-OHDA.


Assuntos
Myrtaceae/química , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Acetilcolinesterase/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Etanol , Hexanos , Humanos , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína Quinase 10 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/enzimologia , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/efeitos dos fármacos , Oxidopamina
8.
Appl Biochem Biotechnol ; 158(2): 302-12, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18716920

RESUMO

In this research, the effects of pH, temperature, and oxygen on growth kinetics of a newly isolated strain of Bacillus circulans from the Amazon and their correlations with transglutaminase (TGase) production and cell sporulation were investigated. Statistical experimental methods were used to optimize these parameters, while induction of sporulation was achieved by oxygen culture control. Full factorial composite experimental design and response surface methodology were experimentally tested. The model showed that temperature has a positive and significant effect on TGase production (P < 0.05) while pH and temperature, associated with anoxic conditions, have a marked effect on cell sporulation which is consistently linked with TGase production. The contour plot of results showed that the best culture conditions for TGase production of B. circulans were 30 degrees C, initial pH 8.5, and the highest production was obtained in late-stationary culture phase with maximal specific enzyme activity of 655 U g(-1) of cells (0.37 U/mL). A correlation between enzyme production and cell sporulation, as mediated by oxygen culture conditions, was also demonstrated and, although demonstrated only for B. subtilis, it corroborates the molecular mechanisms involved in this process. It can be suggested that B. circulans BL32 is a strong biological system for the industrial production of TGases.


Assuntos
Bacillus/enzimologia , Bacillus/crescimento & desenvolvimento , Meio Ambiente , Microbiologia Industrial/métodos , Transglutaminases/metabolismo , Concentração de Íons de Hidrogênio , Esporos Bacterianos/crescimento & desenvolvimento , Temperatura
9.
J Ind Microbiol Biotechnol ; 35(12): 1677-85, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18696133

RESUMO

In this work, we investigated the production of transglutaminase (TGase) by an Amazonian isolated strain of Bacillus circulans by solid-state cultivation (SSC). Several agro-industrial residues, such as untreated corn grits, milled brewers rice, industrial fibrous soy residue, soy hull, and malt bagasse, were used as substrates for microbial growth and enzyme production. Growth on industrial fibrous soy residue, which is rich in protein and hemicellulose, produced the highest TGase activity (0.74 U g(-1) of dried substrate after 48 h of incubation). A 2(3) central composite design was applied to determine the optimal conditions of aeration, cultivation temperature and inoculum cell concentration to TGase production. The best culture conditions were determined as being 0.6 L air min(-1), 33 degrees C and 10 log (10) CFU g(-1) of dried substrate, respectively. Under the proposed optimized conditions, the model predicted an enzyme production of 1.16 U g(-1) of dried substrate, closely matching the experimental activity of 1.25 U g(-1). Results presented in this work point to the use of this newly isolated B. circulans strain as a potential alternative of microbial source for TGase production by SSC, using inexpensive culture media.


Assuntos
Bacillus/enzimologia , Reatores Biológicos , Microbiologia Industrial/métodos , Transglutaminases/biossíntese , Meios de Cultura , Fermentação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA