Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 272
Filtrar
1.
Vitae (Medellín) ; 30(2): 1-11, 2023-05-08. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1538058

RESUMO

Background: The concern about consuming healthy foods has increased in recent years. Not only are they expected to comply with essential feeding functions, but they also provide health benefits. Probiotics are one of the main functional components expected to be present in functional foods and beverages. They provide many health benefits and stand out due to their metabolic capacities and adaptability to different habitats. In addition, Quinoa seeds contain valuable quantities of quality protein and nutritional values of carbohydrates, proteins, fats, fibers, and mineral substances for which they are considered an ideal dietary alternative. Objectives: This research aimed to elaborate on a probiotic quinoa beverage, which combines the effect of enzymatic hydrolysis of the starches obtained from its seeds with lactic acid fermentation using probiotic cultures, seeking to enhance its nutritional properties and converting it into a functional beverage. Methods: For this, fermentations were carried out in three different concentrations of probiotic cultures (inoculum): 10%, 5%, 1%, and three other different fermentation times: 8, 10, and 12 hours. pH, Total titrable acidity expressed as lactic acid (%), reducing sugars, and soluble solids were measured. After that, the beverage was formulated with honey, carob, preservatives, and mango flavoring. Results: Statistical analysis indicated optimal conditions were achieved with 10% probiotic cultures and 10 hours of fermentation. The microbiological analysis confirmed the presence of probiotic microorganisms at a concentration of 108 CFU/mL. Proximal analysis indicated that the composition contained 84.6 Kcal, 19.3 g of carbohydrates, and 1.4 g of protein per 100 g of beverage. Conclusions: The probiotic quinoa beverage was produced and can be considered in the group of plant-based foods, as well as a functional beverage, since the probiotic cultures it contains contribute to maintaining the intestinal microbiota and prevent the onset of chronic diseases.


Antecedentes: La preocupación por el consumo alimentos saludables ha aumentado en los últimos años. No solo se espera que cumplan con las funciones esenciales de alimentación, sino que también brinden beneficios para la salud. Los probióticos son uno de los principales componentes funcionales que se espera que estén presentes en los alimentos y bebidas funcionales. Aportan múltiples beneficios para la salud y destacan por sus capacidades metabólicas y adaptabilidad a diferentes hábitats. Además, las semillas de quinua contienen valiosas cantidades de proteína de notable calidad, valores nutricionales de carbohidratos, proteínas, grasas, fibras y sustancias minerales por lo que se consideran una alternativa dietética ideal. Objetivos: Esta investigación tuvo como objetivo elaborar una bebida probiótica de quinua, que combina el efecto de la hidrólisis enzimática de los almidones obtenidos de sus semillas con la fermentación láctica utilizando cultivos probióticos, buscando potenciar sus propiedades nutricionales y convertirla en una bebida funcional. Métodos: Para ello se realizaron fermentaciones en tres concentraciones diferentes de cultivos probióticos (inóculo): 10%, 5%, 1%, y tres distintos tiempos de fermentación: 8, 10 y 12 horas. Se midió pH, Acidez titulable total expresada como ácido láctico (%), azúcares reductores y sólidos solubles. Posteriormente, se formuló la bebida con miel, algarrobina, conservantes y saborizante de mango. Resultados: El análisis estadístico indicó que se lograron condiciones óptimas con 10% de cultivos probióticos y 10 horas de fermentación. El análisis microbiológico confirmó la presencia de microorganismos probióticos a una concentración de 108 UFC/mL. El análisis proximal indicó que la composición contenía 84,6 Kcal, 19,3 g de carbohidratos y 1,4 g de proteína por 100 g de bebida. Conclusiones: la bebida probiótica de quinua fue elaborada y puede ser considerada en el grupo de alimentos de origen vegetal, así como una bebida funcional, ya que los cultivos probióticos que contiene contribuyen al mantenimiento de la microbiota intestinal y previenen la aparición de enfermedades crónicas.


Assuntos
Humanos , Probióticos , Fermentação , Bebidas Fermentadas , Hidrólise
2.
J. venom. anim. toxins incl. trop. dis ; 27: e20200105, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1180822

RESUMO

Amphibians inhabit the terrestrial environment, a conquest achieved after several evolutionary steps, which were still insufficient to make them completely independent of the aquatic environment. These processes gave rise to many morphological and physiological changes, making their skin (and cutaneous secretion) rich in bioactive molecules. Among the tree frogs, the secretion is composed mainly of peptides; but alkaloids, proteins and steroids can also be found depending on the species. The most known class of biologically active molecules is the antimicrobial peptides (AMPs) that act against bacteria, fungi and protozoans. Although these molecules are well-studied among the hylids, AMPs ontogeny remains unknown. Therefore, we performed peptidomic and proteomic analyses of Pithecopus nordestinus (formerly Phyllomedusa nordestina) in order to evaluate the peptide content in post-metamorphosed juveniles and adult individuals. Methods: Cutaneous secretion of both life stages of individuals was obtained and analyzed by LC-MS/MS after reduction and alkylation of disulfide bonds or reduction, alkylation and hydrolysis by trypsin. Results: Differences in the TIC profile of juveniles and adults in both treatments were observed. Moreover, the proteomic data revealed known proteins and peptides, with slight differences in the composition, according to the life stage and the treatment. AMPs were identified, and bradykinin-potentiating peptides were observed in trypsin-treated samples, which suggests a protein source of such peptide (cryptide). Conclusion: In general, skin secretion contents were similar between juveniles and adults, varying in quantity, indicating that the different stages of life are reflected in the number of molecules and not on their diversity.(AU)


Assuntos
Animais , Feminino , Peptídeos , Tripsina , Proteômica , Anfíbios , Secreções Corporais , Hidrólise
3.
Acta amaz ; 50(4): 346-354, out. - dez. 2020.
Artigo em Inglês | LILACS | ID: biblio-1146380

RESUMO

Fungos filamentosos tem sido alvo de estudos de bioprospecção devido à sua grande eficiencia em produzir enzimas extracelulares, as quais tem grande potencial para uso em bioindústrias. Neste estudo, fungos filamentosos foram isolados do intestino de larvas de insetos aquáticos da Amazônia, para avaliar sua atividade celulolítica. Foram coletadas 69 larvas de insetos aquáticos fragmentadores de três gêneros: Phylloicus (Trichoptera: Calamoceratidae), Triplectides (Trichoptera:Leptoceridae) e Stenochironomus (Diptera: Chironomidae) em dez igarapés de uma área protegida na Amazônia central brasileira. O crescimento dos fungos isolados foi feito em meio de cultura Ágar Batata Dextrose (BDA). Os isolados fúngicos foram transferidos para o meio sintético com Carboximetil celulose e utilizou-se vermelho Congo para determinar o índice enzimático. O halo de hidrólise, indicando a produção de celulases, foi observado em 175 isolados fúngicos (70% do total), dos quais 25 tiveram um índice enzimático ≥ 2,0 e pertencem a sete gêneros fúngicos. Os táxons fúngicos Cladosporium, Gliocephalotrichum, Penicillium, Pestalotiopsis, Talaromyces, Trichoderma e Umbelopsis foram isolados dos intestinos das larvas de Phylloicus, Triplectides e Stenochironomus e são tradicionalmente utilizados em aplicações biotecnológicas. Os resultados indicam um potencial celulolítco destes fungos associados ao intestino de insetos aquáticos amazônicos. (AU)


Assuntos
Celulase , Ecossistema Amazônico , Hidrólise
4.
Electron. j. biotechnol ; 48: 101-108, nov. 2020. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1254920

RESUMO

BACKGROUND: Collagen is the most abundant protein in animals and can be obtained from residues of the food industry. Its hydrolysate has many desirable properties that make it suitable as an additive in foods and cosmetics, or as a component of scaffold materials to be used in biomedicine. RESULTS: We report here the characterization of type I collagen from five different sources, namely bovine, porcine, chicken, trout and salmon, as well as their hydrolysates by means of bioinformatics tools. As expected, the results showed that bovine and porcine collagen, as well as trout and salmon collagen, can be used interchangeably due to their high identity. This result is consistent with the evolution of proteins with highly identical sequences between related species. Also, 156 sequences were found as potential bioactive peptides, 126 from propeptide region and 30 from the central domain, according to the comparison with reported active sequences. CONCLUSIONS: Collagen analysis from a bioinformatic approach allowed us to classify collagen from 5 different animal sources, to establish its interchangeability as potential additive in diverse fields and also to determine the content of bioactive peptides from its in silico hydrolysis.


Assuntos
Animais , Bovinos , Peptídeos , Colágeno/química , Biologia Computacional , Hidrolisados de Proteína , Salmão , Suínos , Análise por Conglomerados , Colágeno Tipo I , Aditivos em Cosméticos , Aditivos Alimentares , Hidrólise
5.
Electron. j. biotechnol ; 46: 38-49, jul. 2020. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1223238

RESUMO

BACKGROUND: Quizalofop-p-ethyl (QPE), a unitary R configuration aromatic oxyphenoxypropionic acid ester (AOPP) herbicide, was widely used and had led to detrimental environmental effects. For finding the QPEdegrading bacteria and promoting the biodegradation of QPE, a series of studies were carried out. RESULTS: A QPE-degrading bacterial strain YC-XJ1 was isolated from desert soil and identified as Methylobacterium populi, which could degrade QPE with methanol by cometabolism. Ninety-seven percent of QPE (50 mg/L) could be degraded within 72 h under optimum biodegradation condition of 35°C and pH 8.0. The maximum degradation rate of QPE was 1.4 mg/L/h, and the strain YC-XJ1 exhibited some certain salinity tolerance. Two novel metabolites, 2-hydroxy-6-chloroquinoxaline and quinoxaline, were found by high-performance liquid chromatography/mass spectroscopy analysis. The metabolic pathway of QPE was predicted. The catalytic efficiency of strain YC-XJ1 toward different AOPPs herbicides in descending order was as follows: haloxyfop-pmethyl ≈ diclofop-methyl ≈ fluazifop-p-butyl N clodinafop-propargyl N cyhalofop-butyl N quizalofop-p-ethyl N fenoxaprop-p-ethyl N propaquizafop N quizalofop-p-tefuryl. The genome of strain YC-XJ1 was sequenced using a combination of PacBio RS II and Illumina platforms. According to the annotation result, one α/ß hydrolase gene was selected and named qpeh1, for which QPE-degrading function has obtained validation. Based on the phylogenetic analysis and multiple sequence alignment with other QPE-degrading esterases reported previously, the QPEH1 was clustered with esterase family V. CONCLUSION: M. populi YC-XJ1 could degrade QPE with a novel pathway, and the qpeh1 gene was identified as one of QPE-degrading esterase gene.


Assuntos
Propionatos/metabolismo , Quinoxalinas/metabolismo , Methylobacterium/metabolismo , Microbiologia do Solo , Biodegradação Ambiental , Methylobacterium/enzimologia , Methylobacterium/genética , Análise de Sequência de Proteína , Esterases/análise , Esterases/metabolismo , Herbicidas , Hidrolases/análise , Hidrolases/metabolismo , Hidrólise
6.
Electron. j. biotechnol ; 44: 60-68, Mar. 2020. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1087705

RESUMO

Background: Oleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources. Results: A total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1 . Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using Box­Behnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids. Conclusion: The fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification


Assuntos
Trichosporon/metabolismo , Oryza , Xilose/isolamento & purificação , Trichosporon/química , Óleos/química , Lipogênese , Biocombustíveis , Fermentação , Glucose/isolamento & purificação , Hidrólise , Lignina/metabolismo , Lipídeos/biossíntese
7.
Rev. chil. nutr ; 47(1): 14-21, feb. 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1092739

RESUMO

Se evaluó el efecto de la temperatura sobre la desnaturalización de proteínas y la reacción de Maillard en leche entera y descremada con lactosa hidrolizada. Las leches hidrolizadas se trataron térmicamente a 100, 110, 120 y 130 °C durante un período de 1 hora y se midió la concentración de glucosa, el grado de pardeamiento y la desnaturalización de proteínas. El grado de dorado en la leche entera varió de 14.4 (100 °C) a 42.6 (130 °C). Para la leche descremada fue de 20.2 (100 °C) a 38.0 (130 °C). La concentración de glucosa en leche entera (47% p/v) y en leche descremada (41% p/v) después del tratamiento térmico (130 °C) mostró una reducción significativa en relación con el control (25 °C). El efecto de la temperatura en la desnaturalización de proteínas en leche entera y descremada en relación con el control (25 °C) fue del 100%. La leche tratada térmicamente con lactosa hidrolizada promovió la desnaturalización de proteínas con un aumento del pardeamiento característico de la reacción de Maillard, lo que afectó la calidad nutricional.


The effect of temperature in protein denaturation and Maillard reaction in whole and skim milk with hydrolyzed lactose was evaluated. Hydrolyzed milk was thermally treated at 100, 110, 120 and 130 °C over a period of 1 hour and glucose concentration, browning degree and protein denaturation were measured. The browning degree in whole milk varied from 14.42 (100 °C) to 42.63 (130 °C) and 20.21 (100 °C) to 38.03 (130 °C) in skim milk. Glucose concentration in whole milk (47% - w/v) and skim milk (41% - w/v) after heat treatment (130 °C) showed a significant reduction in relation to the control (25 °C). The temperature effect in protein denaturation in whole and skim milk in relation to the control (25 °C) was 100%. Thermally treated milk with hydrolyzed lactose promoted protein denaturation with increasing browning characteristic of the Maillard reaction, thus affecting the nutritional quality.


Assuntos
Desnaturação Proteica , Temperatura , Reação de Maillard , Leite/química , Lactose/química , Tratamento Térmico , beta-Galactosidase , Cor , Glucose/análise , Hidrólise
8.
Braz. J. Pharm. Sci. (Online) ; 56: e18817, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132040

RESUMO

A simple, accurate, precise and robust stability indicating RP-HPLC assay method has been developed for the estimation of trimethobenzamide in stress sample. An isocratic separation of trimethobenzamide was achieved on Kromasil 100 C-18 column (250 X 4.6mm, 5µ) with a flow rate of 1.0 ml/min and by using a photodiode array detector to detect the analyte at 213nm. The optimized mobile phase consisted of methanol: ammonium formate (44:56, v/v). The drug was subjected to different forced degradation conditions according to ICH guidelines including acid, base, neutral hydrolysis, oxidation, photolysis and thermal degradation. Degradation products were found only in basic and oxidative degradation conditions. All the degradation products got eluted in an overall analytical run time of 12min. The developed analytical method has been validated according to the ICH guidelines. Response of trimethobenzamide was linear over the concentration range of 0.5-50µg/mL (r2 = 0.999). Accuracy was found to be in between 94.03% to 100.39%. Degradation products resulting from the stress studies did not interfere with the detection of the analyte.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , /análise , Estudo de Validação , Métodos , Preparações Farmacêuticas/administração & dosagem , Hidrólise
9.
Braz. J. Pharm. Sci. (Online) ; 56: e18660, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132061

RESUMO

The effect of drying method, a process variable, on the powder and compaction properties of microcrystalline cellulose (MCC) obtained from the partial acid hydrolysis of bleached alpha (α) cellulose content of matured linters of Gossypium herbaceum (GH) was investigated. A portion of the wet MCC obtained was fluid bed dried at 60 ± 1 ºC, inlet air of 30 m3 min-1 for 3 h (coded MCC-GossF). The second portion was lyophilized at - 45 ± 2 ºC for 6 h (coded MCC-GossL). The physicochemical, scanning electron micrographs, X ray diffraction patterns and micromeritic properties of the derived MCCs were determined using standard methods. The cohesiveness and compactibility of the powders were investigated using Kawakita model while the deformation and compressibility pattern were determined using Heckel model. Avicel® PH 102 (AV-102) was used as comparing standard. Ash values of < 2%, pH (6.54 ± 0.23 to 6.58 ± 0.08), degree of polymerization, DP (231.50) was obtained. MCC-GossF had higher moisture content, swellability, better flow indices, and lesser porosity than MCC-GossL. Kawakita model demonstrated good consolidation and compactibility for both powders. Compacts of MCC-GossL were significantly (p < 0.05) harder than those of MCC-GossF. Heckel analysis demonstrated good compressibility and deformation pattern that was comparable with AV-102. Compacts of MCC-GossL had better mechanical and tablet compression properties than MCC-GossF


Assuntos
Pós , Cinzas/efeitos adversos , Celulose/classificação , Gossypium herbaceum/análise , Baías/análise , Ar , Concentração de Íons de Hidrogênio , Hidrólise , Métodos
10.
Braz. arch. biol. technol ; 63: e20190151, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132269

RESUMO

Abstract A comprehensive comparison of the main fermentation parameters, productivity, yield and final L-lactic acid concentration, obtained through batch, fed-batch and continuous cultivations using Lactobacillus casei CCDM 198 and a model cultivation medium was carried out. Using this data, a pulse-feed fed-batch process was established for testing chicken feather hydrolysate as a replacement for all complex nitrogen sources (yeast and beef extracts and peptone) in the medium. As comparably high values of productivity (about 4.0 g/L/h) and yield (about 98 %) were reached under all cultivation conditions, the maximum final L-lactic acid concentration (116.5 g/L), as achieved through pulse-feed fed-batch fermentation, was chosen as the most important criterion for process selection. Fed-batch cultivation with chicken feather hydrolysate as both a complex nitrogen source and a neutralizing agent for maintaining constant culture pH yielded half the concentration of L-lactic acid compared to the model medium. We demonstrate here that chicken feather hydrolysate has potential for use in the production of L-lactic acid but its utilization requires further optimization


Assuntos
Animais , Ácido Láctico/metabolismo , Fermentação , Lacticaseibacillus casei/crescimento & desenvolvimento , Biotecnologia/métodos , Cromatografia Líquida de Alta Pressão , Biomassa , Reatores Biológicos , Hidrólise
11.
Rev. argent. microbiol ; 51(3): 201-207, set. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1041825

RESUMO

The consumption of soybean isoflavones (IS) is associated with several beneficial properties on human health. Some lactic acid bacteria possess ß-glucosidase enzyme, that allows to obtain the active form of IS (aglycone). The solid state fermentation (SSF) has received great attention in the last years in order to obtain several valuable compounds. SSF, using soybean as substrate and Lactobacillus rhamnosus CRL 981 as starter, was studied in the present work. Sucrose was added into soybean paste to study the effect on the behavior of the selected strain. The development of L. rhamnosus CRL 981 through pH and recount measures, sugar intake, organic acid production, ß-glucosidase activity and IS conversion were analyzed. No significant differences in growth and acidity were observed between soybean pastes with and without sucrose added, but the production of lactic acid was higher in the latter paste. The ß-glucosidase activity was detected in both pastes and the complete hydrolysis of IS at 12 h of fermentation was observed. Also, this strain was able to increase the free amino acids in soybean paste. SSF, using soybean as substrate and L. rhamnosus CRL 981 as starter culture, is an alternative process to obtain a soybean product bio-enriched in active IS with attractive nutritional characteristics.


El consumo de isoflavonas de soja (IS) está asociado a diversos beneficios para la salud humana. Ciertas bacterias lácticas poseen la enzima ß-glucosidasa, que permite obtener la forma bioactiva (agliconas) de las IS. La fermentación en sustrato sólido (FSS) ha recibido gran atención en los últimos anos debido a sus numerosas ventajas, y permite la obtención de productos con valor agregado. En el presente trabajo se estudió la FSS utilizando soja como sustrato y Lactobacillus rhamnosus CRL981 como cultivo iniciador. Con el fin de estudiar el efecto de una fuente de carbono externa sobre el comportamiento de la cepa seleccionada, se adicionó sacarosa a la pasta de soja. Se evaluó el crecimiento de L. rhamnosus CRL 981 a través de medidas de pH y recuento en placa. Además, se analizó el consumo de azúcares, producción de ácidos orgánicos, actividad ß-glucosidasa y conversión de IS. No se observaron diferencias significativas en el crecimiento y acidez entre las pastas de soja sin adición de sacarosa y con ella, sin embargo, la producción de ácido láctico fue mayor en esta última. La actividad de ß-glucosidasa se detectó en ambas pastas y se observó la hidrólisis completa de IS a las 12 h de fermentación. Además, esta cepa fue capaz de aumentar los aminoácidos libres en la pasta de soja. La FSS, utilizando soja como sustrato y L. rhamnosus CRL 981 como cultivo iniciador, es un proceso alternativo para obtener un producto de soja bioenriquecido en IS bioactivas con características nutricionales atractivas.


Assuntos
Soja/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Fermentação , Produtos Vegetais/análise , Isoflavonas/biossíntese , Sacarose/farmacologia , Proteínas de Bactérias/metabolismo , beta-Glucosidase/metabolismo , Ácido Láctico/biossíntese , Microbiologia de Alimentos , Aminoácidos/metabolismo , Hidrólise
12.
Electron. j. biotechnol ; 41: 95-99, sept. 2019. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1087252

RESUMO

Background: Pretreatment is the critically important step for the production of ethanol from lignocelluloses. In this study, hardwood birch (Betula pendula) and softwood spruce (Norway spruce) woods were pretreated with a newly synthesized morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]), followed by enzymatic hydrolysis and fermentation to ethanol. Results: [HMMorph][Cl] was synthesized using inexpensive raw materials, i.e., hydrochloric acid and N-methyl morpholine, following a simple process. The influence of pretreatment time (2, 3, 5, and 8 h) and temperature (120 and 140°C) in terms of hydrolysis efficiency was investigated. Glucose yields from enzymatic hydrolysis were improved from 13.7% to 45.7% and 12.9% to 51.8% after pretreatment of birch and spruce woods, respectively, under optimum pretreatment conditions (i.e., at 140°C for 3 h) as compared to those from pristine woods. Moreover, the yields of ethanol production from birch and spruce were increased to 34.8% and 44.2%, respectively, while the yields were negligible for untreated woods. Conclusions: This study demonstrated the ability of [HMMorph][Cl] as an inexpensive agent to pretreat both softwood and hardwood.


Assuntos
Betula/metabolismo , Etanol/metabolismo , Etanol/síntese química , Lignina/metabolismo , Celulose/metabolismo , Cloretos/química , Abies , Biocombustíveis , Fermentação , Hidrólise
13.
Electron. j. biotechnol ; 41: 1-8, sept. 2019. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1053552

RESUMO

Background: The bioethanol produced from biomass is a promising alternative fuel. The lignocellulose from marginal areas or wasteland could be a promising raw material for bioethanol production because it is present in large quantities, is cheap, renewable and has favorable environmental properties. Despite these advantages, lignocellulosic biomass is much more difficult to process than cereal grains, due to the need for intensive pretreatment and relatively large amounts of cellulases for efficient hydrolysis. Therefore, there is a need to develop an efficient and cost-effective method for the degradation and fermentation of lignocellulosic biomass to ethanol. Results: The usefulness of lignocellulosic biomass from wasteland for the production of bioethanol using pretreatment with the aid of ionic liquids of 1-ethyl-3-methylimidazolium acetate and 1-ethyl-3-methylimidazolium chloride was evaluated in this study. The pretreatment process, enzymatic hydrolysis and alcoholic fermentation lasted a total of 10 d. The largest amounts of bioethanol were obtained from biomass originating from agricultural wasteland, in which the dominant plant was fireweed (Chamaenerion angustifolium) and from the field where the common broom (Cytisus scoparius) was the dominant. Conclusions: The plants such as fireweed, common broom, hay and goldenrod may be useful for the production of liquid biofuels and it would be necessary in the further stage of research to establish and optimize the conditions for the technology of ethyl alcohol producing from these plant species. Enzymatic hydrolysis of biomass from agricultural wastelands results in a large increase in fermentable sugars, comparable to the enzymatic hydrolysis of rye, wheat, rice or maize straw.


Assuntos
Solo/química , Biomassa , Etanol/metabolismo , Biodegradação Ambiental , Celulases/análise , Enzimas/metabolismo , Líquidos Iônicos , Biocombustíveis , Hidrólise , Lignina/análise
14.
Electron. j. biotechnol ; 40: 78-83, July. 2019. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1053493

RESUMO

Background: Mathematical modeling is useful in the analysis, prediction, and optimization of an enzymatic process. Unlike the conventional modeling methods, Monte Carlo method has special advantages in providing representations of the molecule's spatial distribution. However, thus far, Monte Carlo modeling of enzymatic system is namely based on unimolecular basis, not suitable for practical applications. In this research, Monte Carlo modeling is performed for enzymatic hydrolysis of lactose for the purpose of real-time applications. Results: The enzyme hydrolysis of lactose, which is conformed to Michaelis­Menten kinetics, is modeled using the Monte Carlo modeling method, and the simulation results prove that the model predicts the reaction kinetics very well. Conclusions: Monte Carlo modeling method can be used to model enzymatic reactions in a simple way for real-time applications.


Assuntos
Método de Monte Carlo , Enzimas/metabolismo , Hidrólise , Lactose/metabolismo , Fatores de Tempo , Cinética , beta-Galactosidase/metabolismo , Enzimas Imobilizadas , Galactose/metabolismo
15.
Electron. j. biotechnol ; 39: 52-60, may. 2019. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1052027

RESUMO

BACKGROUND: Biologically active peptides produced from fish wastes are gaining attention because their health benefits. Proteases produced by halophilic microorganisms are considered as a source of active enzymes in high salt systems like fish residues. Hence, the aim of this study was the bioprospection of halophilic microorganisms for the production of proteases to prove their application for peptide production. RESULTS: Halophilic microorganisms were isolated from saline soils of Mexico and Bolivia. An enzymatic screening was carried out for the detection of lipases, esterases, pHB depolymerases, chitinases, and proteases. Most of the strains were able to produce lipases, esterases, and proteases, and larger hydrolysis halos were detected for protease activity. Halobacillus andaensis was selected to be studied for proteolytic activity production; the microorganism was able to grow on gelatin, yeast extract, skim milk, casein, peptone, fish muscle (Cyprinus carpio), and soy flour as protein sources, and among these sources, fish muscle protein was the best inducer of proteolytic activity, achieving a protease production of 571 U/mL. The extracellular protease was active at 50°C, pH 8, and 1.4 M NaCl and was inhibited by phenylmethylsulfonyl fluoride. The proteolytic activity of H. andaensis was used to hydrolyze fish muscle protein for peptide production. The peptides obtained showed a MW of 5.3 kDa and a radical scavenging ability of 10 to 30% on 2,2-diphenyl-1-picrylhydrazyl and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and a ferric reducing ability of plasma. Conclusion: The use of noncommercial extracellular protease produced by H. andaensis for biologically active peptide production using fish muscle as the protein source presents a great opportunity for high-value peptide production.


Assuntos
Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo , Proteínas de Peixes/metabolismo , Halobacillus/enzimologia , Solo , Bactérias/isolamento & purificação , Bolívia , Esterases , Salinidade , Hidrólise , Lipase , México , Proteínas Musculares , Antioxidantes
16.
Hig. aliment ; 33(288/289): 1105-1109, abr.-maio 2019. graf, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482108

RESUMO

A lactose é o carboidrato predominante no leite e responsável por diversas reações importantes no processamento de derivados lácteos. Contudo, também é responsável pelo desconforto trazido às pessoas intolerantes à este açúcar. A indústria vem se aprimorando para retirar ou reduzir a lactose dos produtos lácteos. Este trabalho objetivou testar o método de hidrólise para reduzir o teor de lactose no leite de vaca pasteurizado utilizando três concentrações de enzima diferentes e observar as propriedades físico-químicas decorrentes do processo. Os três tratamentos foram submetidos a 30ºC por tempo suficiente para que a crioscopia de cada um estabilizasse. Os resultados demonstraram que a enzima testada foi eficaz para reduzir o teor de lactose no leite em até aproximadamente 93%, mas nenhum dos tratamentos se enquadraria na legislação vigente como “zero lactose”. As propriedades físico-químicas mantiveram-se dentro dos limites da legislação para leite pasteurizado.


Assuntos
Hidrólise , Lactase/administração & dosagem , Lactase/efeitos adversos , Lactose/química , Leite/química , Fenômenos Químicos
17.
Biosci. j. (Online) ; 35(1): 277-288, jan./fev. 2019. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1048581

RESUMO

The international standards for top glucomannan flour require a minimum of 70% glucomannan. The glucomannan content of Amorphophallus oncophyllus flour was approximately 60%, with starch as the major impurity. Elimination of starch was expected to increase the purity of glucomannan. The purpose of this research was to study starch hydrolysis of the flour using α-amylase. Temperature (35.5-84.5oC), time (0.4-3.6 h) and pH (2.2-8.8) of hydrolysis were selected as independent variables. A central composite design of response surface methodology (RSM) was performed to obtain the optimum condition. This approach was a novelty of this enzymatic purification of A. oncophyllus. Glucomannan content, starch content, and solubility were chosen as the response variables. The models were reliable for predicting the responses (R2≥ 0.771). It was predicted that the highest glucomannan content (93.0%) obtained at the lowest starch content (1.14%), which hydrolysed at pH 6.17, 84.5oC and 3.6 h. Prior the verification of the optimum hydrolysed condition from the model, the glucomannan and starch content was 81.59% and 2.27%, respectively. After purification, the absorbance of the ß-1,4 glycosidic bond increased as a sign of higher glucomannan purity. A less rough surface and irregular shape of the grain morphology was observed after purification.


Os padrões internacionais para a farinha de alta calidade de glucomanan requerem um mínimo de 70% de glucomanan. O conteúdo de glucomanano da farinha de Amorphophallus oncophyllus foi de aproximadamente 60%, com o amido como a maior impureza. Esperava-se que a eliminação do amido aumentasse a pureza do glucomanan. O objetivo desta pesquisa foi estudar a hidrólise do amido da farinha usando α-amilase. A temperature (35,5-84,5oC), o tempo (0,4-3,6 h) e o pH (2,2-8,8) da hidrólise foram selecionados como variáveis independentes. Um desenho central composto pertencente á metodologia da superfície de resposta (MSR) foi realizado para obter a condição ótima. Esta abordagem foi uma novidade desta purificação enzimática de A. oncophyllus. O conteúdo de glucomanan, conteúdo de amido e solubilidade foram escolhidos como as respostas. Os modelos foram confiáveis para predizer as respostas (R2≥ 0,771). Os modelos indicaram que o maior conteúdo de glucomanan (93,0%) foram obtidos no menor conteúdo de amido (1,14%),que hidrolisou a um pH 6,17, 84,5ºC e 3,6 h. Antes da verificação da condição hidrolisada ótima do modelo, o conteúdo de glucomanan e amido foi de 81,59% e 2,27%, respectivamente. Após a purificação, a absorbância da ligação ß-1,4 glicosídica aumentou com um sinal de maior pureza de glucomanan. Uma superfície mais lisa e forma irregular da morfologia do grão foi observada após a purificação.


Assuntos
Amorphophallus , alfa-Amilases , Farinha , Hidrólise
18.
Braz. arch. biol. technol ; 62: e19160816, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011524

RESUMO

Abstract The development of new technologies which increase the production of biofuel without directly compete with food production is required. Microalgal biomass has recently been in the highlight. The role of this biomass is here discussed within the concept of biorefinery and industrial sustainability of bioethanol production. The process of cultivation in order to accumulate around 50% of carbohydrates in the biomass (dry weight) and the importance of water and nutrient recycling are reviewed. Saccharification of biomass using enzymes or acids and alternative processes such as hydrothermal liquefaction and flash hydrolysis are addressed. Since the main monosaccharide in microalgal biomass is glucose, high rates of hydrolysis and fermentation were, generally, achieved (more than 80% of the efficiency as a sum of these two processes). Anaerobic digestion to treat vinasse and the recycling of CO2 from the ethanolic fermentation and biogas could increase the process sustainability. Alternative techniques for the concentration of bioethanol from fermentation broth and for the optimization of fuel transportation are mentioned. Finally, the advantage of using microalgae rather than other sources is estimated with reference to the production rate, even though the cultivation costs are still high.


Assuntos
Biomassa , Etanol/economia , Microalgas , Reciclagem/métodos , Hidrólise
19.
Diaeta (B. Aires) ; 36(165): 22-27, dic. 2018. graf, tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1011982

RESUMO

Introducción: la sintomatología de la alergia a la proteína de leche de vaca conlleva deterioro en el crecimiento y aumento concomitante de las necesidades nutricionales. En niños que consumen fórmula como complemento a la lactancia materna o cuando ésta no es posible, debe indicarse como primera opción una fórmula con proteína extensamente hidrolizada (FeH). Es necesaria una ingesta adecuada para revertir síntomas y recuperar crecimiento. Sin embargo, los lactantes rechazan frecuentemente las FeHs debido al gusto desagradable. Objetivo: evaluar sensorialmente cinco FeH presentes en el mercado, en orden decreciente de aceptación y relacionarlo con ingredientes responsables del sabor. Materiales y Método: se realizó un testeo sensorial ciego en cinco FeH (A, B, C, D y E) en población universitaria. Los 54 participantes fueron entrenados previamente sobre la metodología de testeo y la forma de completar el cuestionario en estaciones individuales. Las fórmulas fueron calificadas con puntaje del 1 al 5 (más aceptable - menos aceptable) y la preferencia se analizó por prueba de Rangos de Wilcoxon (nivel de significación 0,025). Resultados: según el puntaje de aceptación, las fórmulas quedaron ordenadas de la siguiente manera: E, D, A, C, B; de la más aceptable a menos aceptable. La fórmula E fue la "preferida", aunque no presentó diferencias significativas con D. A, C y B mostraron una baja aceptación significativa con respecto a E y D. El análisis de ingredientes mostró mayor aceptación para hidrolizados de suero con presencia de lactosa y/o jarabe de glucosa y grasa saturada. El nivel de hidrólisis y los péptidos resultantes serían factores determinantes en la aceptación. Conclusión: la resultante de las combinaciones de ingredientes y su estructura química podrían ser responsables de mejor sabor o mayor aceptación de las FeH, facilitando la recuperación nutricional del lactante y la adherencia al tratamiento(AU).


Introduction: symptoms coming from allergy to cow's milk protein may impair a child's growth as well as concomitant increase in nutritional needs. In children consuming formula as a supplement to breastfeeding or when breastfeeding is not possible, a formula with extensively hydrolyzed protein (eHF) should be indicated as first option. Adequate intake is necessary to reverse symptoms and regain growth. However, infants frequently reject eHFs due to unpleasant taste. Objective: to sensorially evaluate five eHFs present in the market, in decreasing order of acceptance, and relate them to ingredients responsible for taste. Materials and Methods: blind sensory testing was performed on five eHFs (A, B, C, D and E) in university population. The fifty-four participants were previously trained on testing methodology and how to complete the questionnaire in individual stations. Formulas were scored from 1 to 5 (more acceptable - less acceptable) and preference was analyzed by Wilcoxon Range test (significance level 0.025). Results: based on acceptance score, formulas remained ordered as follows: E, D, A, C, B; from most acceptable to least acceptable. Formula E was the "preferred" one, although it did not show significant differences with D. A, C and B showed a significant low acceptance with respect to E and D. Ingredients analysis showed greater acceptance for whey hydrolysates with presence of lactose and/or glucose syrup and saturated fat. Level of hydrolysis and resulting peptides would be determining factors in acceptance. Conclusion: combinations of ingredients and their chemical structure could be responsible for better taste or greater acceptance of eHFs, facilitating the nutritional recovery of the infant and adherence to treatment(AU).


Assuntos
Hipersensibilidade a Leite , Hidrólise , Necessidades Nutricionais
20.
Rev. chil. nutr ; 45(4): 316-322, dic. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-978092

RESUMO

RESUMEN Se evaluó el efecto de adición de lactasa (β-galactosidasa) y sacarosa (como edulcorante) en una bebida isotónica a partir del lactosuero dulce. Se estableció dos factores en estudio: factor "A" dosis de lactasa 5200 NLU (0,5; 1,1 y 3,0 mL) y factor "B" porcentajes de sacarosa (7 y 8%). La unidad experimental fue de 18.18 kg de lactosuero dulce, distribuidos en seis tratamientos con tres réplicas, formulándose combinaciones: T1 (0,5:7), T2 (0,5:8), T3 (1,1:7), T4 (1,1:8), T5 (3:7) y T6 (3:8). Se evaluó la energia y carbohidratos. Los resultados mostraron diferencias significativas para la variable carbohidratos sobre los tratamientos, y diferencias significativas para el factor "B" sobre la variable carbohidratos. Se determinó al T2 como el mejor tratamiento en base a una prueba afectiva. Los análisis de electrolitos de sodio y potasio realizados al mismo T2 demostraron que el sodio fue el único que cumple con los valores establecidos. La adición de varias dosis de lactasa no incidió en los parámetros sustanciales de una bebida isotónica, mientras que los porcentajes de sacarosa incidieron significativamente sobre las variables respuesta, aumentando los carbohidratos y calorias por encima del valor normado.


ABSTRACT The effect of adding lactase (β-galactosidase) and sucrose (as a sweetener) to an isotonic drink from sweet whey was evaluated. Two factors were studied: factor "A" lactase dose 5200 NLU (0.5, 1.1 and 3 mL) and factor "B" percentages of sucrose (7 and 8%). The experimental unit was 18.18 kg of sweet whey, distributed in six treatments with three replications, creating the following combinations: T1 (0.5: 7), T2 (0.5: 8), T3 (1.1: 7), T4 (1.1: 8), T5 (3: 7) and T6 (3: 8). Energy and carbohydrates were evaluated. The results showed significant differences for the carbohydrate variable over the treatments, and significant differences for the "B" factor over the carbohydrate variable. T2 was determined as the best treatment based on a test of affect. The sodium and potassium electrolyte analyses performed on the same T2 show that sodium was the only one that complied with established values. The addition of several doses of lactase did not affect the substantial parameters of an isotonic drink, while the percentages of sucrose significantly affected the response variables, increasing carbohydrates and calories above normal values.


Assuntos
Carboidratos , Eletrólitos , Bebidas Energéticas , Hidrólise , Sacarose , Lactase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...