A New Advancement in Germination Biotechnology of Purple Creole Corn: Bioactive Compounds and In Situ Enzyme Activity for Water-Soluble Extract and Pan Bread.

Germination is a simple and cost-effective technology that enhances the technological, sensory, and nutritional potential of grains, making them more attractive for use in the food industry. Germinating indigenous seeds is an alternative to increase noticeability and add value to these grains, which hold social and economic significance in the regions where they are cultivated, such as creole purple pericarp corn (PPCC) from the Couto Magalhães de Minas region in Brazil. This study aimed to optimize the germination parameters of time (24-96 h) and temperature (18-32 °C) for PPCC to produce water-soluble extracts and bread. Endogenous enzymes resulting from the germination process significantly enhanced (p < 0.10) the technological (total reducing sugars, total soluble solids, and soluble proteins) and biological properties (γ-aminobutyric acid, total soluble phenolic compounds, and antioxidant capacity) of the water-soluble extracts. The optimum point for obtaining the extracts was found to be at 85.3 h at 30.46 °C (with desirability of 90.42%), and this was statistically validated. The incorporation of germinated PPCC flours into bread was also promising (p < 0.10) and had a positive impact on the dough property (dough volume increase) and the final product, especially in terms of instrumental texture (springiness, cohesiveness, gumminess, chewiness, and resilience), resulting in a softer texture (lower firmness and hardness). The addition of PPCC flours did not alter instrumental color parameters, which may lead to greater consumer acceptance due to imperceptible differences in color to untrained individuals, with the optimized point at 96 h at 29.34 °C, with a desirability of 92.60%. Therefore, germinated PPCC shows promise for use as a base for obtaining water-soluble extracts and in bread as a replacement for commercial flour improvers, while also adding value to a raw material that is part of the local culture and agrobiodiversity.

Novel amylase-producing fungus hydrolyzing wheat and brewing residues, Aspergillus carbonarius, discovered in tropical forest remnant.

Today, many microbial amylases are available commercially and they have almost completely replaced chemical hydrolysis in several industry processes. Amylases from microorganisms have a broad spectrum of industrial applications as they are more stable than amylases obtained from plants and animals. The objective of this work was to use potato baits in an Atlantic Forest remnant located in Ribeirão Preto, São Paulo, Brazil, in order to obtain amylase-producing fungi with potential for biotechnological application. In addition, the culture conditions for the fungal strain that presented higher production of glucoamylase were standardized using industrial wastes. For this, 6 PET bottles containing potatoes as baits were scattered at different points in an Atlantic forest remnant. After 6 days, the samples were collected, and the filamentous fungi were isolated in Petri dishes. Fungi screening was carried out in Khanna liquid medium with 1% starch Reagen®, at 30 °C, pH 6.0, under static conditions for 4 days. Proteins and glucoamylase activity were determined by Bradford and 3,5-dinitrosalicylic acid (DNS), respectively. Among all isolated fungi, A. carbonarius showed the highest glucoamylase production. Its best cultivation conditions were observed in Khanna medium, 4 days, at 30 °C, pH 6.0, under static condition with 0.1% yeast extract and 1% starch Reagen®. Wheat and brewing residues were also used as inducers for large quantities of glucoamylase production. A. carbonarius showed to be a good alternative for the wheat and brewing waste destinations in order to obtain high added value products.

Determination of the biodegradability of chitosan utilizing the most probable number technique

The present work aimed to evaluate the degradability of the chitosan polymer by soil microorganisms.This evaluation was accomplished using the Most Probable Number (MPN) method by plating in drops so that soil microorganisms capable of degrading the polymeric material could be quantified. Soil samples diluted in three specific culture media for each typeof microorganism were plated –bacteria, fungi and actinobacteria–and they were maintained at 28°C for seven days to determine the growth rate of fungi and actinobacteria, and for 48hoursfor the development of bacteria. Significant differences in the MPN of actinobacteriarelative to the other groups analyzed were observed. Thus, the method used was effective for determining the degradability of the chitosan biopolymer when observing the development of microorganisms subjected to the replacement of thecarbonsource by the addition of 2% w v-1of the chitosan biopolymer to the culture medium. The formation of clear regions around the microbial colonies was a strong indicator of biodegradation.

Purification and functional properties of a novel glucoamylase activated by manganese and lead produced by Aspergillus japonicus.

Microbial amylases are used to produce ethanol, glucose and can be applied in textiles products, detergents and other industries. This study aimed to determine the best carbon source concentration to induce the amylase production by A. japonicus, and its purification and biochemical characterization. For that, this fungus was cultivated in Khanna medium, pH 5.5, for 4 days, at 25°C, in static condition, supplemented with potato starch and maltose in different concentrations. The fungal crude enzymatic extract was purified in a unique elution in DEAE-cellulose column and the molecular mass was determined as 72kDa. The optimum temperature and pH was 65°C and 5.0, respectively. Amylase remained 75% of its activity after one hour at 50°C and was stable in the pH range 3.0-7.0. The analysis of the end-products by thin layer chromatography showed only glucose formation, which characterizes the purified enzyme as a glucoamylase. Amylopectin was the best substrate for the enzyme assay and Mn+2 and Pb+2 were good glucoamylase activators. This activation, in addition to the biochemical characteristics are important results for future biotechnological applications of this glucoamylase in the recycling and deinking process by the paper industries.

Screening of thermotolerant and thermophilic fungi aiming β-xylosidase and arabinanase production

Plant cell wall is mainly composed by cellulose, hemicellulose and lignin. The heterogeneous structure and composition of the hemicellulose are key impediments to its depolymerization and subsequent use in fermentation processes. Thus, this study aimed to perform a screening of thermophilic and thermotolerant filamentous fungi collected from different regions of the São Paulo state, and analyze the production of β-xylosidase and arabinanase at different temperatures. These enzymes are important to cell wall degradation and synthesis of end products as xylose and arabinose, respectively, which are significant sugars to fermentation and ethanol production. A total of 12 fungal species were analyzed and 9 of them grew at 45 ºC, suggesting a thermophilic or thermotolerant character. Additionally Aspergillus thermomutatus anamorph of Neosartorya and A. parasiticus grew at 50 ºC. Aspergillus niger and Aspergillus thermomutatus were the filamentous fungi with the most expressive production of β-xylosidase and arabinanase, respectively. In general for most of the tested microorganisms, β-xylosidase and arabinanase activities from mycelial extract (intracellular form) were higher in cultures grown at high temperatures (35-40 ºC), while the correspondent extracellular activities were favorably secreted from cultures at 30 ºC. This study contributes to catalogue isolated fungi of the state of São Paulo, and these findings could be promising sources for thermophilic and thermotolerant microorganisms, which are industrially important due to their enzymes.

A novel glucoamylase activated by manganese and calcium produced in submerged fermentation by Aspergillus phoenicis.

This study investigates the production of glucoamylase from Aspergillus phoenicis in Machado Benassi (MB) medium using 1% maltose as carbon source. The maximum amylase activity was observed after four days of cultivation, on static conditions at 30 °C. Glucoamylase production was induced by maltose and inhibited by different glucose concentrations. The optimum of temperature and pH were 60-65 °C, and 4.5 or 5.0 to sodium acetate and Mcllvaine buffers, respectively. It was observed that the enzyme was totally stable at 30-65 °C for 1 h, and the pH range was 3.0-6.0. The enzyme was mainly activated by manganese (176%), and calcium (130%) ions. The products of starch hydrolysis were analyzed by thin layer chromatography and after 3 h, only glucose was detected, characterizing the amylolytic activity as a glucoamylase.

Screening of thermotolerant and thermophilic fungi aiming ß-xylosidase and arabinanase production.

Plant cell wall is mainly composed by cellulose, hemicellulose and lignin. The heterogeneous structure and composition of the hemicellulose are key impediments to its depolymerization and subsequent use in fermentation processes. Thus, this study aimed to perform a screening of thermophilic and thermotolerant filamentous fungi collected from different regions of the São Paulo state, and analyze the production of ß-xylosidase and arabinanase at different temperatures. These enzymes are important to cell wall degradation and synthesis of end products as xylose and arabinose, respectively, which are significant sugars to fermentation and ethanol production. A total of 12 fungal species were analyzed and 9 of them grew at 45 °C, suggesting a thermophilic or thermotolerant character. Additionally Aspergillus thermomutatus anamorph of Neosartorya and A. parasiticus grew at 50 °C. Aspergillus niger and Aspergillus thermomutatus were the filamentous fungi with the most expressive production of ß-xylosidase and arabinanase, respectively. In general for most of the tested microorganisms, ß-xylosidase and arabinanase activities from mycelial extract (intracellular form) were higher in cultures grown at high temperatures (35-40 °C), while the correspondent extracellular activities were favorably secreted from cultures at 30 °C. This study contributes to catalogue isolated fungi of the state of São Paulo, and these findings could be promising sources for thermophilic and thermotolerant microorganisms, which are industrially important due to their enzymes.