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( Cecilia Perez-cruz ),( Carlos N. Cano-gonzalez ),( Jose Fuentes ),( Nagamani Balagurusamy ),( Carolina E. Vita ),( Roque A. Hours ),( Cristobal N. Aguilar ),( Sebastian F. Cavalitto ),( Juan C. Cont 한국키틴키토산학회 2018 한국키틴키토산학회지 Vol.23 No.3
Aspergillus niger biomass, an industrial by-product of citric acid fermentation is an emergent source of glycoderivatives with applications in biofuel, cosmetics, feed, energy, food, medicine, and nanotechnology. In this study, the effect of purified neutral protease for deprotenization of fungal biomass studied at various levels (0, 5, 10, 20 and 40 U/100 mg of biomass) and the saccharification of fungal biomass was evaluated with amylolytic enzymes and chitosanases. The efficiency of deproteinization of fungal biomass was based on the enzyme concentration and contact time. Protease at a concentration of 20 U/100 mg of dry biomass and with a contact time of 8 h achieved 30% final deproteinization. No effect on saccharification of A. niger biomass was observed by treatment with purified amylolytic enzymes. Meanwhile, the endo- and exo-chitosanases treatment yielded 54 g of g reducing sugars (equivalent to amino sugars)/ kg of fungal biomass, which can be employed for tailor-made carbohydrate production.
Pectin from Passion Fruit Fiber and Its Modification by Pectinmethylesterase
Contreras-Esquivel, Juan Carlos,Aguilar, Cristobal N.,Montanez, Julio C.,Brandelli, Adriano,Espinoza-Perez, Judith D.,Renard, Catherine M.G.C. The Korean Society of Food Science and Nutrition 2010 Preventive Nutrition and Food Science Vol.15 No.1
Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.
Pectin from Passion Fruit Fiber and Its Modification by Pectinmethylesterase
Juan Carlos Contreras-Esquivel,Cristobal N. Aguilar,Julio C. Montanez,Adriano Brandelli,Judith D. Espinoza-Perez,Catherine M.G.C. Renard 한국식품영양과학회 2010 Preventive Nutrition and Food Science Vol.15 No.1
Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at 121℃. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 ㎎/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.
Daniela Sánchez Aldana,Cristobal Noé Aguilar,Juan Carlos Contreras-Esquivel,Marthyna Pessoa Souza,Maria das Graças Carneiro-da-Cunha,Guadalupe Virginia Nevárez-Moorillón 한국원예학회 2021 Horticulture, Environment, and Biotechnology Vol.62 No.5
This work aimed to develop an edible coating based on Mexican lime ( Citrus aurantifolia Swingle) pectic extract and essentialoil on Haden mango ( Mangifera indica L.) to extend its shelf life. Mango cubes were coated by immersion in a lime pecticextract (1% pectin w/v), lime essential oil (0.05% v/v), and glycerol (0.7% v/v) solution for 2, 5, and 10 min. Subsequently,coated and uncoated (control) test samples were stored for 21 days, and physical–chemical and microbiological analyseswere performed every 3 days. The results showed no signifi cant diff erences for total soluble solids, pH, and fi rmness. On thesixth day, bacterial growth was signifi cantly lower in coated mangos than in the control (log 6.08 ± 0.49 and 7.63 ± 0.20 UFCg −1 , respectively). The application of the edible coating extended the shelf life of minimally processed mangos by 3 days,delaying physical and chemical changes as well as bacterial growth.
Improvement of the Quality and Shelf-life of Corn Tortillas by Water Soluble Chitosan
( Araceli Loredo-trevino ),( Alfonso Ocampo-ramirez ),( Ana Veronica Charles-rodriguez ),( Maria De La Luz Reyes-vega ),( Cristobal N. Aguilar ),( Juan Carlos Contreras-esquivel ) 한국키틴키토산학회 2018 한국키틴키토산학회지 Vol.23 No.1
Chitosan-oligosaccharides and water soluble chitosan have wide applications in several industries such as agronomic, cosmetic, feed, food, medicine, and nanotechnology. The aim of this work was to depolymerize chitosan enzymatically using endo-chitosanase from Bacillus sp. and to evaluate the hydrolyzates as fungistatic on corn tortillas prepared with these products. Five water soluble chitosan (2, 4, 8, 12 and 24 h) series were prepared with endo-chitosanase (40ºC, 3.5 U/g chitosan). Two filamentous fungi of contaminated corn tortillas were isolated and later used for the inhibition studies of water soluble chitosan series on agar plates. Furthermore, corn tortillas were elaborated with water soluble chitosan obtained after 4 h of enzyme degradation to evaluate the microbial inhibition effect and sensorial analysis. All water soluble chitosan series were totally soluble in water, except that material modified enzymatically by 2 h. The fungal strains isolated from corn tortillas were Aspergillus sp. and Penicillum sp. Results on microbial radial growth showed that the water soluble chitosan series obtained at the time of 4 h had the biggest effectiveness for the inhibition of growth of both filamentous fungi on agar plate. When the corn tortillas were prepared with water soluble chitosan at a 1% (w/v), a partial inhibition of growth of filamentous fungi was achieved in contrast to the prepared tortillas without this hydrolyzate. Unpleasant flavor was not presented in the corn tortillas by effect of the hydrolyzate addition; this indicates that this material can be used appropriately as food additive in the tortilla industry as inhibitor of microbial growth. This water soluble chitosan can also be considered as a dietary fiber and a prebiotic.
Optimization of Tannase Production by Aspergillus niger in Solid-State Packed-Bed Bioreactor
( Rodriguez Duran Luis ),( Juan C. Contreras Esquivel ),( Raul Rodriguez ),( L. Arely Prado Barragan ),( Cristobal N. Aguilar ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.9
Tannin acyl hydrolase, also known as tannase, is an enzyme with important applications in the food, feed, pharmaceutical, and chemical industries. However, despite a growing interest in the catalytic properties of tannase, its practical use is very limited owing to high production costs. Several studies have already demonstrated the advantages of solid-state fermentation (SSF) for the production of fungal tannase, yet the optimal conditions for enzyme production strongly depend on the microbial strain utilized. Therefore, the aim of this study was to improve the tannase production by a locally isolated A. niger strain in an SSF system. The SSF was carried out in packed-bed bioreactors using polyurethane foam as an inert support impregnated with defined culture media. The process parameters influencing the enzyme production were identified using a Plackett-Burman design, where the substrate concentration, initial pH, and incubation temperature were determined as the most significant. These parameters were then further optimized using a Box-Behnken design. The maximum tannase production was obtained with a high tannic acid concentration (50 g/l), relatively low incubation temperature (30oC), and unique low initial pH (4.0). The statistical strategy aided in increasing the enzyme activity nearly 1.97-fold, from 4,030 to 7,955 U/l. Consequently, these findings can lead to the development of a fermentation system that is able to produce large amounts of tannase in economical, compact, and scalable reactors.