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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.
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.
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.
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.
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.
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.
Guillermo Cristian Guadalupe M,Louise Wicker,Cristobal Noe Aguilar,Raul Rodriguez-Herrera,Juan Carlos Contreras-Esquivel 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.3
An acidic polygalacturonase (PG) from Aspergillus kawachii was produced by solid state fermentation employing a polyurethane foam support. The conditions used for the production of acidic PG were particle size of support (0.6 or 500 ㎣) and fermentation time. From the factors studied, the particle size had important influence on enzyme production. The best conditions for acidic PG production were 0.6 ㎣ particle size, 18 hr at 30℃ and initial pH of 5.0. In addition, pectin was extracted from citrus pomaces (grapefruit, lime, and tangerine) by acidic PG at 50℃ for 24 hr with citric acid solution. Infrared spectroscopy showed that lime pomace had more high-methoxylated (65%) endogenous pectin than was obtained than from grapefruit or tangerine pomaces. The enzymatically extracted pectin yield in dry basis (d.b.) for grapefruit and lime pectins were 6.95 and 4.25%, respectively. The citric acid solution alone also contributed to pectin extraction from citrus pomaces (7-9%, d.b.). Limited pectin extraction by acidic PG from tangerine pomace was most likely due to the presence of low-methoxylated endogenous pectin. The enzymatic method for pectin extraction using acidic PG from A. kawachii is a promising technique for releasing highly polymerized pectic substances from high-methoxylated lime or grapefruit pomaces.
Luz M. Ramos-Ponce,Mireille Vega,Edith Colunga-Urbina,Georgina C. Sandoval-Fabián,Nagamani Balagurusamy,Juan Carlos Contreras-Esquivel,Francisco J. Rodriguez-Gonzalez 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.3
A colorimetric method for quantitative measurement of free amino groups of water soluble chitin derivatives is described. The method utilizes genipin as a natural and specific reagent for determining the concentration of free amino groups in samples of water soluble chitin derivatives. The blue color adduct (complex) formed during genipin reaction with free amino groups was measured at about 589 nm and Beer-Lambert’s law obeyed over the concentration range of 50 to 300 mg/L. Parameters of analytical conditions were considered and kept constant during the experimental procedure. Highly acetylated water soluble chitin derivatives can be differentiated from water soluble chitosan using this genipin method. The colorimetric method with genipin was proved to be a rapid and efficient technique to determine the free amino groups in water soluble chitin derivatives. This method can also be applied for the detection of the enzymatic activity of chitindeacetylase.