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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.
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.
Pectolytic Enzymes of the Industrial Fungus Aspergillus kawachii
Carolina Elena Vita,Juan Carlos Contreras Esquivel,Claudio Enrique Voget 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.6
Aspergillus kawachii extracellular pectinases were screened in liquid cultures with different carbon sources. The fungus grown on citrus pectin or lemon pomace produced at least one of these inducible pectinases: acidic polygalacturonase, pectin lyase, pectin methylesterase, α-L-arabinofuranosidase, α-1,5-endoarabinase, β-D-galactosidase/exogalactanase, and β-1,4-endogalactanase. The lemon-pomace filtrates also contained significant α-L-rhamnosidase and β-D-fucosidase activities. Most of the screened pectinases were active at pH 2.0-2.5, indicating that the A. kawachii enzymes were acidophilic. Under the culture conditions employed we could not detect enzymatic degradation of soybean rhamnogalacturonan. The A. kawachii pectinase-production-related regulatory phenomena of induction-repression resemble those described for other Aspergillus sp.
Rapid physicochemical characterization of innovative fucoidan/fructan powders by ATR-FTIR
Espinosa-Velazquez, Gerardo,Ramos-de-la-Pena, Ana Mayela,Montanez, Julio,Contreras-Esquivel, Juan Carlos 한국식품과학회 2018 Food Science and Biotechnology Vol.27 No.2
Functional food has been highly demanded lately because of its benefits in counteracting diseases. Fucoidan and agave fructan are ingredients that enhance the growth of beneficial bacteria in the gut (prebiotics). This mixture has great potential to develop innovative products but it has never been explored before. Because of fucoidan is more expensive than agave fructan, the innovative proposed mixture is vulnerable to adulteration. This research was aimed to assess the accuracy of Fourier transform infrared spectroscopy with attenuated total reflectance (ATR-FTIR) coupled with chemometrics to identify and predict concentration of both polysaccharides in powder mixtures (0-100%). Absorption bands at 1240-1255 and $836-840cm^{-1}$ were attributed to fucoidan and a strong peak at ${\sim}936cm^{-1}$ confirmed the fructan presence. Peak areas were best fitted into linear models ($R^2_{adj}{\geq}0.92$, $RMSE{\leq}3.54%$). This achievement may be useful to certificate ingredients contained in fucoidan-fructan mixtures, preventing adulteration.
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.
Presence of Transgenic Genes and Proteins in Commercial Soybean Foods from Mexican Grocery Stores
Yendi Arely Cruz-Flores,Raul Rodriguez-Herrera,Cristobal Noe Aguilar-Gonzalez,Juan Carlos Contreras-Esquivel,Maria de la Luz Reyes-Vega 한국식품과학회 2008 Food Science and Biotechnology Vol.17 No.5
Commercial food products from major cities of Coahuila, Mexico were screened to identify residues of transgenic deoxyribonucleic acid (DNA) and/or proteins. After performed, an inventory on all products that contained a soybean-based ingredient in a commercial grocery store in the city of Saltillo, Coahuila, Mexico, 245 food products were identified and grouped in 15 classes according to the soybean ingredient as well as the manufacturing process used for their elaboration. Similar sampling was made for the different food classes in the cities of Monclova, Piedras Negras, and Torreon. A total of 88 samples were analyzed and DNA was extracted by the hexadecyltrimethyl-ammonium bromide (CTAB) technique with slight modification to obtain better DNA quality (1). In addition, segments of the transgenic genes one that codifies for 5-enolpyruvylshikimate-3-phosphate synthase (epsps), cry 1A, and the cauliflower mosaic virus (CaMV) promoter were amplified using polymerase chain reaction (PCR). The transgenic proteins 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) and insecticidal crystal protein (Cry 1Ab/Ac) were identified using double antibody sandwich-enzymatic linked immunoassay analysis (DAS-ELISA). Presence of transgenic genes and/or proteins was identified in 35.3% of the commercial products samples.