Physicochemical properties of carboxymethylated flamboyant (Delonix regia) seed gum Propiedades fisicoquímicas de la goma carboximetilada de flamboyán (Delonix regia)

Abstract

The worldwide high consumption of food additives has encouraged to perform research on new species producers of gums or hydrocolloids that can compete with those that are traditionally used, such as flamboyant (Delonix regia) seed gum, a species considered underutilized and of ornamental type. Flamboyant tree seeds were used to obtain a native gum (flamboyant gum (FNG)), which was modified by carboxymethylation (CFG), this reaction was confirmed using Fourier transformed infrared (FTIR) spectroscopy and colorimetric titration. Swelling index and dispersion were evaluated in a range of 30-90 8C. The apparent viscosity (m) was evaluated with a rheometer. Compression strength of the gel (CSG) was measured with a texture analyzer and calorimetric profile with differential scanning calorimetry (DSC). The CFG had a degree of substitution of 0.33 and the FTIR analysis indicated the presence of carboxy-ether groups in the CFG. The modification of the FNG increased dispersion by 66%. Both gums exhibited shear-thinning behaviors although carboxymethylation caused a decrease in viscosity. The DSC showed a state crystalline in the FNG and a state amorphous in the CFG. The modification of the FNG favored hydrogen bridge interactions with water but decreased intra-catenary interactions in the polysaccharide.Keywords: carboxymethylation; Delonix regia; flamboyant; seed gum; functional properties El alto consumo de aditivos alimentarios a nivel mundial incentiva la investigacio´n de nuevas especies productoras de gomas o hidrocoloides que puedan competir con aque´llas usadas tradicionalmente, tal es el caso de la goma de la semilla de flamboya´n (Delonix regia), especie subutilizada y considerada de tipo ornamental. Las semillas de flamboya´n fueron usadas para obtener goma nativa (FNG), la cual fue modificada por carboximetilacio´n (CFG), esta reaccio´n se confirmo´usando espectroscopia de infrarrojo con transformada de Fourier (FTIR) y titulacio´n colorime´trica. El ı´ndice de hinchamiento y la dispersio´n en agua fueron evaluados de 30 a 90 8C. La viscosidad aparente (m) fue evaluada con reo´metro. La fuerza de compresio´n del gel (CSG) fue medida con un analizador de textura y el perfil calorime´trico con un calorı´metro diferencial de barrido (DSC). La CFG tuvo un grado de sustitucio´n de 0,33. La modificacio´n de la FNG incremento´la solubilidad en un 66%. Ambas gomas tuvieron un comportamiento reofluidizante. La carboximetilacio´n ocasiono un decremento de la m. El DSC mostro´un estado cristalino en la FNG y amorfo en la CFG. La modificacio´n de la FNG favorecio´las interacciones puentes de hidro´geno con el agua pero disminuyo´las interacciones intracatenarias en el polisaca´rido.

Characterization of Guazuma ulmifolia Lam. seed gum and its effect on the activity of Metarhizium anisopliae (Metschn.) Sorokin on Bemisia tabaci Genn

“…Swelling index (SI) and water dispersion (WDIS) were determined by using the method reported by Pacheco-Aguirre et al, (2010), taking 40 ml of a 1% (w/v) dilution of GG extract in distilled water in four 50 ml centrifuge tubes. The tubes were heated separately in a water bath to 4 different temperatures (30, 50, 70 and 90°C) for 30 minutes.…”

“…Viscosity (µ) of seed gum was determined by using the method reported by Pacheco-Aguirre et al, (2010). This was carried out using an AR-2000 rheometer (TA Instrument) with a cone and plate geometry (20 mm diameter and 4° angle) and a shear rate range from 1 to 500 s -1 .…”

“…Gums or hydrocolloids are long chain polysaccharides, characterized by their property of forming viscous dispersions or gels in water. Natural gums can be found in gummy slimes from fermentation processes, seaweeds, plant exudates, plant extracts and seed flours (Pacheco-Aguirre et al, 2010). Gums has been used in industrial products as thickeners, stabilizers, emulsifiers, coatings, encapsulants and carriers.…”

“…Currently, research on non-conventional gums has opened new avenues on novel uses of these products and have replaced the use of synthetic gums (El Kader et al, 2008). Several studies has found promising results with gums from seeds of the Fabaceae Leucaena leucocephala, Delonix regia, Adenanthera pavonina, Caesalpinia pulcherrima, Gleditsia triacanthos and Sophora japonica (El Kader et al, 2008;Pacheco-Aguirre et al, 2010;Cerqueira et al, 2009), the Malvaceae Durio zibethinus and Guazuma ulmifolia (Mirhosseini & Amid, 2012;Carrascosa & Lorenzo, 2013), the Brassicaceae Lepidium perfoliatum and Alyssum homolocarpum (Koocheki et al, 2009;Koocheki et al, 2010), and the Lamiaceae Ocimum basilicum (Hosseini et al, 2010). G. ulmifolia is a tree that grows in tropical zones of Mexico, South America and in the Caribbean.…”

Development of a Delonix regia decorticating machine

“…8,9 Gums extracted from D. regia seed makes it potentially resourceful in the food industry. 10 Seed oil extracted from D. regia has potential for control of maize weevils. This facilitates traditional grain storage practices if incorporated in grain storage system.…”