Extraction of high methoxyl pectin from unripe waste Ponkan mandarine (Citrus reticulata Blanco cv. Ponkan) with an eco-friendly solvent.

The aqueous batch extraction of pectin from unripe Ponkan mandarin was evaluated for potential application in the food industry. A small central composite design with 4 variables (temperature, volume to mass ratio, pH, and mean particle size) and 3 levels was applied for pectin extraction optimization. Also, the kinetic of the pectin yield extraction was investigated at temperatures 70-90 °C, stirring rate of 100-700 rpm, ultrasound pretreatment system, and modeling using four mathematical models. The pectin extraction process was evaluated by yield of pectin and esterification degree. FTIR, TGA, and DTA were performed to evaluate the quality of pectin obtained. The small central composite design demonstrated that temperature and volume to mass ratio were significant variables, and the highest yield of pectin extraction was 11.62 % obtained at temperature and volume to molar ratio of 81.9 °C and 33.9 v/w %, respectively. Besides, the esterification degree showed higher than 70 % for all extraction conditions, suggesting high methoxyl pectin. The kinetics showed the stirring rate and the ultrasound pretreatment did not cause any significant alteration, while high temperatures proved to be beneficial to the rate and the yield of the pectin extraction. The best fit was provided by Fick's law, suggesting the extraction process is limited by internal mass transfer. FTIR showed the functional groups expected for pectin, and TGA and DTA indicated that the pectin obtained is proper for most food products, as only above 200 °C the pectin should degrade.

Brine Solution with Hydrocolloids Used to Enhance the Properties of Sterilized Meat.

RESEARCH BACKGROUND: Retort processing is one of the most widely used methods of thermal inactivation that provides convenient, ready-to-eat foods. Although this technology remains widespread, it can be revamped through processing of novel ingredients such as gums. This article aims to investigate the effect of the hydrocolloids collagen, soy protein isolate, carrageenan and modified starch with different salt mass fractions on the retorted meat products. EXPERIMENTAL APPROACH: Firstly, solutions of the added hydrocolloids of different salt mass fractions in order to stimulate the salting-in effect were studied. Lipid oxidation, syneresis and water activity were analysed during shelf life to find the best overall treatments. Lastly, sensory and texture analyses were then performed to assess the impact of the added hydrocolloids. RESULTS AND CONCLUSIONS: Yield, cooking loss and water-holding capacity had better results when higher salt mass fractions with hydrocolloids were used. The physicochemical results distinguished collagen from the other tested hydrocolloids. Syneresis remained in similar ranges regardless of the treatment. No difference was observed in water activity either. However, sterilization, vacuum sealing and the addition of a hydrocolloid contributed to low oxidation levels in all treatments. Lastly, sensory, texture and shear force analyses confirmed that the products with collagen were harder and firmer than the control samples, which explains the preference of control samples by the panellists. Nevertheless, assessors did not perceive the presence of collagen. NOVELTY AND SCIENTIFIC CONTRIBUTION: Physicochemical and sensory characteristics of the retorted meat can be considerably improvedwhen brine and hydrocolloids are combined with the retort technology.

An overview of cell disruption methods for intracellular biomolecules recovery.

Bacteria, yeast, and microalgae are sources of biomolecules such as enzymes, lipids, pigments, organic acids and, proteins for industrial application. These high-added-value biomolecules are often intracellularly bioaccumulated, and their recovery involves several downstream processes, in which the most crucial stage is the disruption of the cell wall. The choice of the method influences the further downstream steps and, consequently, its complexity and cost. In this review, severe and gentle methods currently used for disruption or permeabilization of bacteria, yeast, and microalgae were discussed based on their principle, application, and feasibility. Also, recent studies regarding the microbial cell disruption were presented in order to facilitate the choice of the more effective method. Some factors such as cell wall composition, nature of biomolecule, purity degree, scalability, and energy input are necessary to be considered on selecting the most appropriate disruption method. The severe methods, such as high pressure-homogenization, and ultrasonication present higher yield, lower cost, and feasibility to scale-up when compared to the gentle methods. However, in order to achieve a higher recovery yield, further studies must focus on the optimization of operational parameters and on the combination of severe and gentle methods.

Studies towards the stabilisation of a mushroom phytase produced by submerged cultivation.

A novel phytase from Ganoderma australe G24 was produced by submerged cultivation and recovery. Liquid and solid forms of phytase were developed; both types of product were formulated using different additives. Ganoderma australe G24 phytase was very stable in liquid form with NaCl and sodium acetate buffer. Solid form products were obtained by spray-drying using different polymers to encapsulate the phytase and the capsules obtained were analyzed by electron microscopy. Micrographs confirmed micro and nanoparticles formed with maltodextrin (300 nm to 7-8 µm) without the presence of agglomerates. The use of maltodextrin for solid formulation of G. australe G24 phytase is recommended, and resulted in good stability after the drying process and during storage (shelf life). Kinetic models of phytase inactivation in the microencapsulated powders over time were proposed for the different stabilizing additives. Inactivation rate constants, half-lives and D values (decimal reduction time) were obtained. Phytase encapsulated with maltodextrin remained stable after 90 days, with k 0.0019 day(-1) and a half-life (t1/2) of 367.91 days(-1).

Evaluation of probiotic properties of Pediococcus acidilactici B14 in association with Lactobacillus acidophilus ATCC 4356 for application in a soy based aerated symbiotic dessert

The aim of this study was to evaluate the probiotic properties of Pediococcus acidilactici B14 and to study its resistance in the gastrointestinal system when combined with Lactobacillus acidophilus ATCC 4356 and used in a potentially symbiotic aerated soy based dessert. P. acidilactici B14 showed some important probiotic characteristics such as survival rate of 45.9% at pH 2.5; 72.4% in 0.3% bile salts and 95.8% after gastrointestinal transit at pH 4.0. Tolerance against the antibiotics cephalexin, neomycin, vancomycin, cefotaxime and penicillin G was also observed. The strain inhibited antagonism against the following cultures: Escherichia coli ATCC 25922, Bacillus cereus ATCC 33018, Staphylococcus aureus ATCC 6538P and Salmonella sp. The mixed culture of P. acidilactici B14 with L. acidophilus ATCC 4356 showed a survival rate of 92.4% after the passage through the gastrointestinal system at pH 4.0. Furthermore, in the presence of the food matrix, an average increase in cell viability, after being subjected to the gastrointestinal system of 9.9% at pH 2.0 and 6.1% at pH 4.0, was observed. This characterized the adequacy of the associated culture as probiotic in the development of a functional food such as soy based aerated symbiotic dessert.

Analysis of inducers of xylanase and cellulase activities production by Ganoderma applanatum LPB MR-56.

This manuscript describes the analysis of the effect of cellulose, carboxymethylcellulose (CMC), xylan, and xylose as inducers of cellulase and xylanase activity production by Ganoderma applanatum MR-56 and the optimization of their production in liquid cultures by statistical methods. The Plackett-Burman screening design was applied to identify the most significant inducers of xylanase and cellulase activities production by G. applanatum MR-56. The most significant effect on xylanase and cellulase activities production was exercised by cellulose, even if xylose and CMC were also effective at some times. The combined effect of cellulose, yeast extract, and pH was analyzed by a 2(3) factorial experimental design with four central points that showed that the maximum tested cellulose (1 % w/v) and yeast extract (5 g L(-1)) concentrations gave the maximum production of xylanase (8.24 U mL(-1)) and cellulase (3.29 U mL(-1)) activity at pH 6 and 4, respectively. These values achieved for cellulase and xylanase activity represent 12-25 fold and 36 fold higher values than the maximum so far reported for other strains of G. applanatum, respectively.

Effect of forced aeration on citric acid production by Aspergillus sp. mutants in SSF.

Citric acid (CA) is one of the most important products of fermentation in the world. A great variety of agro-industrial residues can be used in solid state fermentation. Aspergillus niger parental strain (CCT 7716) and two strains obtained by mutagenesis (CCT 7717 and CCT 7718) were evaluated in Erlenmeyer flasks and glass columns using citric pulp (CP) as substrate/support, sugarcane molasses and methanol. Best results using glass columns (forced aeration) were found in the fourth day of fermentation: 278.4, 294.9 and 261.1 g CA/kg of dry CP with CCT 7716, CCT 7718 and CCT 7717, respectively. In Erlenmeyer flasks (aeration by diffusion) CA reached 410.7, 446.8 and 492.7 g CA/kg of dry CP with CCT 7716, CCT 7718 and CCT 7717, respectively. The aeration by diffusion improved CA production by the three strains. A data acquisition system specially developed for biotechnological processes analysis was used to perform the respirometric parameters measurement.

Partial characterization of an inulinase produced by Aspergillus japonicus URM5633

Enzymes obtained by fermentation processes offer a number of advantages and have been widely researched and used throughout the world. This study aimed to partially characterise an inulinase produced from palm and cassava peel. The enzyme was produced via the solid-state fermentation of Aspergillus japonicus URM5633. The optimal temperatures were 50ºC and 55ºC, and the optimal pH values were 5.2 and 3.4 for inulinase fermentatively produced from palm and cassava peel, respectively. The thermostability measurements for inulinase produced in palm showed that the relative activity remained below 100% until 30 minutes of stability for all temperatures, but reached 106.8% at a temperature of 50ºC after 60 minutes. Inulinase from the crude extract of cassava peel was pH stable and only decreased to 55% of the maximal activity over the course of the assay, suggesting that this enzyme can be used in inulinase production and can be utilized in food industries.

A bioprocess for the production of phytase from Schizophyllum commune: studies of its optimization, profile of fermentation parameters, characterization and stability.

Schizophyllum commune produces phytase through solid-state fermentation using different agroindustrial residues. After optimization of phytase production, a maximal level of phytase (113.7 Units/gram of dry substrate) was obtained in wheat bran based medium containing 5% sucrose, 50% humidity, 7.5% of biomass at 33 °C pH 7.0 during 72 h and a 285% improvement in enzyme titre was achieved. Analysis of fermentation parameters profile for phytase production showed the highest productivity (1.466 Units/gram of dry substrate/hour) in 66 h of fermentation. Phytase has an optimal pH of 5.0, an optimal temperature of 50 °C and K (m) and V (max) values of 0.16 mM and 1.85 µmol mL(-1) min(-1), respectively. Phytase activity was stimulated essentially in the presence of K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), Cu(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), acetate and citrate at concentrations of 1 mM. Phytase had the best shelf life when stored at a cooling temperature, maintaining 38% of its initial activity after 112 days of storage, and still presenting enzymatic activity after 125 days of storage. Stability studies of phytase performed in aqueous enzyme extracts showed satisfactory results using polyethyleneglycol 3350, carboxymethylcellulose, methylparaben, mannitol and benzoic acid in concentrations of 0.25, 0.025, 0.025, 0.25, and 0.0025%, respectively. PEG 3350 was shown to be the best stabilizing agent, resulting in 109% of phytase activity from the initial crude extract remaining activity in after 90 days.

Formulated products containing a new phytase from Schyzophyllum sp. phytase for application in feed and food processing

A new formulated product containing high yield of phytase from Schizophyllum sp., an important mushroom used for medicinal studies, was developed for application in feed industries and for future use in food processing. The enzyme presented a high activity yield 55.5 U/mL and 6240 U/gds in liquid and solid formulated product, respectively. It showed a good shelf-life in concentrated product, retaining 67.8 percent of its activity after 60 days of storage at room temperature and 90 percent of the activity was maintained in the liquid formulation after the same period. Powder bioformulated product maintained 77 percent of its activity after two months of storage, without the addition of chemical additives, which was named as a new bioformulated product containing high quantities of phytase. After separation and concentration steps, enzyme stability was monitored in two forms: liquid and solid. The liquid product was stable with the presence of manitol and polyethylene glycol at 1 percent (w/v), while solid product was the most stable product without the presence of chemical additives.

Production biomolecule with inhibitory activity against Gram-negative bacteria isolated from faeces of broilers and swine

The aim of this study was to investigate the potential of lactic acid bacteria, bacilli and yeasts isolates to produce antimicrobial substances, especially against Gram-negative bacteria isolated from the animal faeces, searching for a new alternative to control the enteritis diseases in animal health. Evaluations were performed by microdilution in broth using crude extract obtained from the cultivation of 272 strains against Escherichia coli, S. Typhimurium, S. Enteritidis and Pseudomonas aeruginosa. Thirty-five lactic acid bacteria presented some antimicrobial action. One Lactobacillus isolate, named FLPB-1, was selected to studies the kinetics of the production. An important increase in the production was obtained when the producer strain had cell-to-cell contact with a Gram-positive inducer culture. Maximal production of antimicrobial compounds was obtained in the beginning of stationary phase and the addition of urea in the medium increased the inhibition rate.

Lichtheimia blakesleeana as a new potencial producer of phytase and xylanase.

Brazil is known for its great potential for production of renewable resources such as agro-industrial residues. These residues can be used as alternative sources of new products. Meanwhile, solid-state fermentation, with its advantages of energy conservation and pollution reduction, has been identified as a process of great potential for the production of bioactive compounds, especially enzymes. In the present work, a 2(3) factorial design was used to evaluate the effects of pH, temperature and moisture on the production of phytase and xylanase by Lichtheimia blakesleeana URM 5604 through the fermentation of citrus pulp. Statistical analyses of the results showed that the only the pH influenced the production of these enzymes, with the best phytase production (264.68 U/g) ocurring at pH 6.0, 34 °C, initial moisture 50%, after 48 hours of culture. The best conditions for xylanase production (397.82 U/g) were fermentation for 120 hours at pH 4.0, 26 °C and initial moisture of 70%. The best parameters for the simultaneous production of phytase (226.92 U/g) and xylanase (215.59 U/g) were determined to be initial moisture of 50%, pH 6.0, 26 °C, and 48 hours of fermentation.

Monitoring fermentation parameters during phytase production in column-type bioreactor using a new data acquisition system.

Fermentation parameters for phytase production in column-type bioreactor were monitored using a new data acquisition system. There are a number of studies reporting phytase production in flasks, but a lack of data about microorganism respiration behaviour during phytase production using column bioreactor. The objectives of this work were the monitoration of fermentation parameters during phytase production and its relation with fungal growth and forced air. Phytase production by A. niger FS3 increased with forced air. The O(2) consumption and CO(2) production during solid-state fermentation were monitored by sensors (in the bottom and top of the columns) linked to controllers, recorded by acquisition software and processed by Fersol2(®) software tool. Phytase synthesis was associated with fungal growth. Therefore, phytase could be used to estimate FS3 biomass formed in citric pulp degradation.

Utilization of the biorreactor of imersion by bubbles at the micropropagation of Ananas comosus L. Merril

The research for new techniques of in vitro cultivation is being object of many studies around the world, in order to optimize and decrease production costs of seedlings with agronomical interest. The main goal of this work was to compare different systems of in vitro cultivations using Ananas comosus L. Merril. So, the in vitro growth of the plantlets was promoted in two different bioreactors: Bioreactor of Immersion by Bubbles (B.I.B.®) and the Reactor of Temporary Immersion (R.I.T.A.®) with immersion cycle every 2 hours for 15 minutes and the traditional system in flasks with 200 mL. All cultivation systems used the MS liquid nutritive solution, supplemented with BAP (1 mgL-1), ANA (0.25 mgL-1), sucrose (30 gL-1) and Tween 20® (0.5 µL). The pH was adjusted to 5.8 and sterilized at 120°C for 15 minutes. The cultures were kept into a growth room during 30 days, with controlled temperature of 25±2°C, under white cold light (46.8 µmol.m-2.s-1), with photoperiod of 16 hours. The experimental design used was randomized, with three treatments, three repetitions and ten plants each stage. Among the evaluated systems, the BIB® presented the best results for the tested variables, mainly the total number of shoots, being 2.3 e 3.1 times superior when compared with the system R.I.T.A.® and the traditional consecutively. So the system of immersion by bubbles turns into an effective equipment to produce seedlings of pineapple in large scale.

A busca por novas técnicas de cultivo in vitro vem sendo amplamente estudadas, visando otimizar e baixar o custo de produção das mudas que tenham interesse agronômico. O objetivo deste trabalho foi comparar diferentes sistemas de cultivo in vitro de Ananas comosus L. Merril. Para tanto, o crescimento in vitro de plântulas foi promovido em sistemas de biorreatores (B.I.B.® e R.I.T.A.®) com ciclo de imersão a cada 2 horas por 15 minutos e o sistema tradicional em frascos de 200 mL. Em todos os sistemas de cultivo, foram utilizadas solução nutritiva líquida MS, suplementado com 1 mg L-1 de BAP, 0,25 mg L-1 de ANA, 30 g L-1 de sacarose e 0,5 µL de Tween® 20, pH ajustado para 5,8 e autoclavagem a 120°C por 15 minutos. As culturas foram mantidas em sala de crescimento durante 30 dias, temperatura controlada de 25±2°C, sob luz branca fria (46,8 µmol.m-2.s-1), com 16 horas de fotoperíodo. O delineamento foi inteiramente casualizado, com três tratamentos, três repetições e dez plantas por estágios. Para os sistemas avaliados, o biorreator de imersão por bolhas apresentou os melhores resultados dentre as variáveis analisadas, com destaque ao número total de brotações, sendo 2,3 e 3,1 vezes superiores quando comparado com o sistema R.I.T.A.® e sistema tradicional respectivamente. Portanto, o sistema de imersão por bolhas torna-se um equipamento eficaz na produção de mudas de abacaxizeiro em larga escala.

A simplified model for A. Niger FS3 growth during phytase formation in solid State fermentation

A simplified model to describe fungal growth during citric pulp fermentation for phytase production was described for the first time. Experimental data for biomass growth were adjusted to classical mathematical growth models (Monod and Logistic). The Monod model predictions showed good agreement with the experimental results for biomass concentration during 96 hours of fermentation. Parameters such as yield of biomass from oxygen (Y X/O), maintenance coefficient (m) and specific growth rate (µ) were compared showing a good correlation between the data and the model. An alternative method for biomass determination in this process was developed since a great correlation was found between biomass growth and enzyme formation.

Um modelo simplificado para descrever o crescimento fúngico durante a fermentação em polpa citric para a produção da fitase foi descrita pela primeira vez. Dados experimentais para a formação de biomassa foram ajustados a modelos clássicos de crescimento microbiano (Monod e Logístico). O modelo Monod previsto mostrou boa correlação aos resultados experimentais para a concentração de biomassa até 96 horas de fermentação. Parâmetros como rendimento de biomassa a partir de oxigênio (Y X/O), coeficiente de manutenção (m) e taxa específica de crescimento (µ) foram comparados mostrando uma boa correlação entre os dados e o modelo. Um método alternativo para a determinação de biomassa neste processo foi desenvolvido a partir de uma excelente correlação encontrado entre o crescimento microbiano e a formação da enzima.