Structure-function relationship of licorice (Glycyrrhiza glabra) root extract-xanthan/guar gum mixture in a high sugar content system.

BACKGROUND: Foam-gels are one of the most important multicomponent-model systems in aerated confectionery, and an investigation of their microstructure is desirable. In this research, the structure-function relationship of xanthan gum/guar gum (XG/GG) and licorice (Glycyrrhiza glabra) root extract powder (LEP) was investigated in a high-sugar medium. Foam-gel systems were prepared at 4:10% to 8:20% ratios of LEP to biopolymer. RESULTS: The results show that increasing the LEP content reduced both the melting point and enthalpy, probably due to higher overrun and weaker junctions. Boosting the XG/GG ratio led the enhancement of mechanical properties, whereas increasing the LEP concentration weakened all textural parameters, which could be due to the poor structure of the network in the presence of the foaming agent, increased moisture content and overrun. In the whipped mixture samples containing 10 g kg-1 XG/GG, higher foaming capacity was observed. By increasing the level of biopolymers, smaller and more uniform air cells were formed according to a scanning electron microscopical study. At higher concentration of LEP, smaller bubbles and increased porosity were seen, which could be attributed to the availability of surfactant in the interfacial layer. CONCLUSION: Maximum structural strength was achieved at a 4:20 ratio of LEP to XG/GG. In rheological experiments, pseudoplastic behavior was seen in all samples. Generally, this model system can be simulated for other herbal extracts containing natural surfactants such as saponins. Achieving a more detailed understanding of these structures and their interactions could help in formulating novel food products. © 2021 Society of Chemical Industry.

Physicochemical and release behaviour of phytochemical compounds based on black jamun pulp extracts-filled alginate hydrogel beads through vibration dripping extrusion.

The phytochemical-rich extract obtained from black jamun pulp were encapsulated using vibrating dripping extrusion technique. The utilisation of alginate (AL) with four variations of core-shell material comprising gum Arabic (AL-GA), guar gum (AL-GG), pectin (AL-P) and xanthan gum (AL-X) was engaged to form calcium-alginate based lyophilised jamun extract encapsulated beads. It resulted that among four variations, lyophilised alginate with AL-GG based encapsulated jamun extract filled beads have better physicochemical characteristics and 95% encapsulation efficiency. The results revealed the morphological comparison of each variation. The release behaviour of AL-GG based beads has a higher release of total phenolics (TPC) and total anthocyanin content (TAC). The release kinetics model involving Ritger-Peppas and Higuchi model were applied for release TPC and TAC of all variations of beads. The Ritger-Peppas model was found best suitable in terms of average R2 (0.965) and lowest χ2 (0.0039). The release kinetics study showed that AL-GA based beads followed by AL-GG could also be the best suitable in release behaviour using simulated gastrointestinal fluids at 140-160 min. Overall, results shown the encapsulated Jamun beads have the best agro-industrial efficacy in form of phytochemical compounds based microparticles, holding decent antioxidant potential.

Structure conformation, physicochemical and rheological properties of flaxseed gums extracted under alkaline and acidic conditions.

The present work aimed at investigating an extraction protocol based on consecutive steps of isoelectric point (pH ~ 4.25) mediated gum swelling and deproteinisation as an alternative method to produce flaxseed gum extracts of enhanced techno-functional characteristics. The osidic and proximate composition, structure conformation, flow behaviour, dynamic rheological and thermal properties of gums isolated from brown and golden flaxseeds were assessed. Gum extraction under near-to-isoelectric point conditions did not impair the extraction yield, residual protein and ash content, whilst it resulted in minor changes in the sugar composition of the flaxseed gum extracts. The deconvolution of the GPC/SEC chromatographs revealed the presence of four major polysaccharidic populations corresponding to arabinoxylans, rhamnogalacturonan-I and two AX-RG-I composite fractions. The latter appeared to minimise the intra- and interchain polymer non-covalent interactions (hydrogen bonding) leading to a better solvation affinity in water and lyotropic solvents. Golden flaxseed gums exerted higher molecular weight (Mw = 1.34-1.15 × 106 Da) and intrinsic viscosities (6.63-5.13 dL g-1) as well as better thickening and viscoelastic performance than the brown flaxseed gum exemplars. Golden flaxseed gums exhibited a better thermal stability compared to the brown flaxseed counterparts and therefore, they are suitable for product applications involving severe heat treatments.

Growth, yield and quality of two guar (Cyamopsis tetragonoloba L.) ecotypes affected by sowing date and planting density in a semi-arid area.

The growth period, phenology, grain yield and gum content of two different guar ecotypes were studied in response to different sowing dates and plant densities. A two-year field experiment was conducted as a split-factorial in a randomized complete block design (RCBD) with three replicates in the research field of Tarbiat Modares University during 2016 and 2017 growing season. Main plots consisted of four sowing dates (May 21, June 4, June 21 and July 5 in 2016 and May 10, May 26, June 10 and June 26 in 2017), and subplots including three plant densities (13, 20 and 40 plants m-2) and two ecotypes (Pakistani and Indian). Based on findings, the phenological traits, plant height, grain yield and harvest index were significantly affected by plant density. The effect of ecotypes was statistically significant (p<0.05) on all traits except harvest index in the first year. Furthermore, the seed sowings on May 21 and May 26 with 13 plants m-2 led to highest grain yield (3004.8 and 2826.10 kg.ha-1 for two consecutive years). The high gum content (33.68 and 33.78% for two consecutive years) was also recorded for Pakistani ecotype while for gravity, Indian ecotype showed higher value in both crop years. By and large, the Pakistani ecotype showed better response compared to the Indian one in both years, especially in 1st and 2nd sowing dates.

Synthesis, characterization and use of enzyme cashew gum nanoparticles for biosensing applications.

This research reports, for the first time, the immobilization of an enzyme - Rhus vernificera laccase - on cashew gum (CG) nanoparticles (NPs) and its application as a biological layer in the design and development of an electrochemical biosensor. Laccase-CG nanoparticles (LacCG-NPs) were prepared by the nanoprecipitation method and characterized by UV-Vis spectrophotometry, atomic force microscopy, scanning electron microscopy, attenuated total reflectance-Fourier-transform infrared spectroscopy, circular dichroism, cyclic voltammetry, and electrochemical impedance spectroscopy. The average size and stability of the NPs were predicted by DLS and zeta potential. The ATR-FTIR results clearly demonstrated an interaction between -NH and -OH groups to form LacCG-NPs. The average size found for LacCG-NPs was 280 ± 53 nm and a polydispersity index of 0.309 ± 0.08 indicated a good particle size distribution. The zeta potential shows a good colloidal stability. The use of a natural product to prepare the enzymatic nanoparticles, its easy synthesis and the immobilization efficiency should be highlighted. LacCG-NPs were successfully applied as a biolayer in the development of an amperometric biosensor for catechol detection. The resulting device showed a low response time (6 s), good sensitivity (7.86 µA µM-1 cm-2), wide linear range of 2.5 × 10-7-2.0 × 10-4 M, and low detection limit (50 nM).

Design of facile technology for the efficient removal of hydroxypropyl guar gum from fracturing fluid.

With the increasing demand for energy, fracturing technology is widely used in oilfield operations over the last decades. Typically, fracturing fluids contain various additives such as cross linkers, thickeners and proppants, and so forth, which makes it possess the properties of considerably complicated components and difficult processing procedure. There are still some difficult points needing to be explored and resolved in the hydroxypropyl guar gum (HPG) removal process, e.g., high viscosity and removal of macromolecular organic compounds. Our works provided a facile and economical HPG removal technology for fracturing fluids by designing a series of processes including gel-breaking, coagulation and precipitation according to the diffusion double layer theory. After this treatment process, the fracturing fluid can meet the requirements of reinjection, and the whole process was environment friendly without secondary pollution characteristics. In this work, the fracturing fluid were characterized by scanning electron microscopy (SEM), Energy dispersive X-ray (EDX), X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) spectroscopy technologies, etc. Further, the micro-stabilization and destabilization mechanisms of HPG in fracturing fluid were carefully investigated. This study maybe opens up new perspective for HPG removal technologies, exhibiting a low cost and strong applicability in both fundamental research and practical applications.

Comparison of the Effect of Ceratonia siliqua L. (Carob) Syrup and Vitamin E on Sperm Parameters, Oxidative Stress Index, and Sex Hormones in Infertile Men: a Randomized Controlled Trial.

Herbal products with an antioxidant capacity can boost male reproductive functions. The empiric use of Ceratonia siliqua (carob) for its antioxidant properties is common among infertile men in Iran and Turkey. The objective of this study is to investigate the effects of C. siliqua (carob) on semen parameters, oxidative stress markers, and pregnancy rate in a parallel randomized, controlled study. A total of 60 infertile men with oligozoospermia, asthenospermia, and teratospermia were recruited from April 2018 to March 2019. Participants were divided randomly into the following two groups: carob syrup twice a day or vitamin E 100 mg twice a day for 3 months. Semen analysis was performed and hormonal levels and stress oxidative markers were measured in each treatment arm after 3 months. The quality of semen parameters improved in the carob group compared with Vit E semen count (p = 0.04 Cohen's d = .51), morphology (p = 0.001 Cohen's d = .93) and motility parameters (p = 0.002 Cohen's d = .90) were significantly higher in the carob group. No significant difference can be detected in post-treatment hormonal parameters and oxidative markers between groups, except for total antioxidant capacity(TAC) which was higher after post-treatment in carob group. A significantly higher pregnancy rate was found among the carob group. The administration of carob may be an effective agent for the improvement of semen parameters, probably related both to its involvement in the changing of testosterone level and to its antioxidant properties. Nevertheless, additional studies to evaluate the optimal dose and duration of treatment are needed. The trial has been registered in the Iranian Registry of Clinical Trials (Registration number: IRCT20171209037794N1.

Furcellaran: An innovative biopolymer in the production of films and coatings.

Seaweed is a prominent source of polysaccharides with extraction processes properly established, allowing to employ them in several areas. Among all the types of biopolymers obtained from seaweed, furcellaran has gained notoriety in recent years. This is due to its abundance, water solubility and outstanding film-forming abilities. Despite still being little studied, in several works, remarkable advances in terms of improving properties of furcellaran-based films have been described in the literature. However, there are still numerous research opportunities to be explored regarding the improvement of material properties. Therefore, the objective of this review is to highlight the innovative method in preparation, characterization and performance of furcellaran-based films as food packaging. This is the first study in which current results in the area are presented. Initially, it concerns biopolymer chemical and extraction insights. In addition, a comprehensive description of the advances in film properties is outlined (from mechanical to active/intelligent responses). Ultimately, challenges and future prospects are also discussed.

Extraction, Purification, and Characterization of Polysaccharides of Araucaria heterophylla L and Prosopis chilensis L and Utilization of Polysaccharides in Nanocarrier Synthesis.

BACKGROUND: Plant gums consist of polysaccharides which can be used in the preparation of nanocarriers and provide a wide application in pharmaceutical applications including as drug delivery agents and the matrices for drug release. The objectives of the study were to collect plant gums from Araucaria heterophylla L and Prosopis chilensis L and to extract and characterize their polysaccharides. Then to utilize these plant gum-derived polysaccharides for the formulation of nanocarriers to use for drug loading and to examine their purpose in drug delivery in vitro. METHODS: Plant gum was collected, polysaccharide was extracted, purified, characterized using UV-Vis, FTIR, TGA and GCMS and subjected to various bioactive studies. The purified polysaccharide was used for making curcumin-loaded nanocarriers using STMP (sodium trimetaphosphate). Bioactivities were performed on the crude, purified and drug-loaded nanocarriers. These polysaccharide-based nanocarriers were characterized using UV-Vis spectrophotometer, FTIR, SEM, and AFM. Drug release kinetics were performed for the drug-loaded nanocarriers. RESULTS: The presence of glucose, xylose and sucrose was studied from the UV-Vis and GCMS analysis. Purified polysaccharides of both the plants showed antioxidant activity and also antibacterial activity against Bacillus sp. Purified polysaccharides were used for nanocarrier synthesis, where the size and shape of the nanocarriers were studied using SEM analysis and AFM analysis. The size of the drug-loaded nanocarriers was found to be around 200 nm. The curcumin-loaded nanocarriers were releasing curcumin slow and steady. CONCLUSION: The extracted pure polysaccharide of A. heterophylla and P. chilensis acted as good antioxidants and showed antibacterial activity against Bacillus sp. These polysaccharides were fabricated into curcumin-loaded nanocarriers whose size was below 200 nm. Both the drug-loaded nanocarriers synthesized using A. heterophylla and P. chilensis showed antibacterial activity with a steady drug release profile. Hence, these natural exudates can serve as biodegradable nanocarriers in drug delivery.

Influence of different extraction techniques on recovery, purity, antioxidant activities, and microstructure of flaxseed gum.

Four extraction techniques (that is, hot water extraction [HWE], alkaline-acidic extraction [AAE], ultrasound assisted extraction [UAE], and microwave assisted extraction [MAE]) were compared for flaxseed gum extraction and their influence on the yield, purity, structural characterization (monosaccharide composition, molecular weight distribution, and microstructure by transmission electron microscope), and antioxidant activity (in terms of scavenging ability of 2,2-diphenyl-1-picrylhydrazyl [DPPH], 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid [ABTS], and reducing power) was investigated. The HWE achieved higher yield (8.96%) than UAE (7.84%) followed by MAE (7.01%) and AAE (6.44%). Moreover, the four flaxseed gum (FSG) samples exhibited the identical monosaccharide composition, but slight difference was observed in the content, whereas the molecular weight ratios exhibited significant difference. All samples displayed concentration-dependent manner for all antioxidant assays. UAE-FSG showed significant higher scavenging ability on DPPH free radical, ABTS free radical, reducing power, and ß-carotene bleaching assay followed by HWE-FSG, MAE-FSG, and AAE-FSG. Overall results showed that UAE was favorable to the purity of FSG, whereas HWE was more advantageous to improve the extraction yield and facile as it requires no special equipment. PRACTICAL APPLICATION: Extraction methods directly affect the recovery and purity of the extracted compound. Thus, this study could help in selection of appropriate extraction method for FSG. The results suggested that FSG possesses potential healthcare application in food industry because of their nutrition composition and antioxidant activities, and thus, it can be used for formulation of functional food as a natural antioxidant agent.

Extraction of a novel water-soluble gum from nettle (Urtica dioica) seeds: Optimization and characterization.

Nettle seed gum (NSG) which is a novel potential source of hydrocolloid was characterized in terms of yield, physicochemical, rheological, functional and thermal properties. According to Response Surface Methodology, the maximum extraction yield was determined as 6.17% on dry basis. In order to clarify the structural information of the gum, the FT-IR analysis and monosaccharide composition determination were performed. In the results, the NSG had 8.48% moisture, 10.81% total ash, 2.89% total protein, 1.15% total oil and 76.67% total carbohydrate. The FT-IR analysis revealed the existence of carboxyl groups, which gives the gum the capability of ion binding. Furthermore, Mannose/Galactose ratio was calculated as 1.07, indicating the water solubility of gum. DSC analysis showed that the NSG was highly stable in thermal process. Intrinsic viscosity, average viscosity and molecular weight values were determined as 8.56 ± 0.4 dL/g and 1.89 ± 0.1 × 106 g/mol, respectively. The emulsification capacity, emulsion stability and foam formation capacity of the NSG were 48%, 40% and 4%, respectively. The NSG exhibited shear thinning behavior while dynamic rheological analysis indicated the NSG had viscoelastic properties and G' (the storage modulus) was higher than G″ (the loss modulus). In conclusion, the present study supplied novel knowledge on the NSG, which will be inestimable for clarifying its matchless functional properties.

Rheological, structural and physicochemical characteristics of heat-induced egg albumin/sesbania gum mixed gels.

The effects of sesbania gum (SG) on the rheological and physicochemical properties of heat-induced egg albumin gels were investigated. The formation of the gels of egg albumin (4%, w/v)/SG (0, 0.1, 0.2 and 0.3%, w/v) mixtures were induced by heating. It was evident from the appearance of gels' microstructure that phase separation occurred in egg albumin/SG systems. Non-Newtonian pseudoplastic flow behavior was observed in all the gels and it was further evident that 0.1% of SG could significantly (p < 0.05) improve the apparent viscosity of the egg albumin gels. The rheological characteristics of the gels demonstrated a more stable and plastic character gel formed at 0.1% SG. The temperature stability test showed that the structures of egg albumin/SG gels maintain their stability when reheated. The hardness of the egg albumin gels was improved with the addition of 0.1% SG, and their water holding capacity (WHC) was also improved. For egg albumin gel with 0.1% SG, a three-dimensional stranded network was observed, indicating the formation of a more stable and tight gel. The FTIR results confirmed that egg albumin and SG are thermodynamically incompatible, which suggested that there is no covalent bonding between egg albumin and SG.

Functional, thermal and rheological behavior of fenugreek (Trigonella foenum-graecum L.) gums from different cultivars: A comparative study.

Fenugreek gum (FG) was isolated from six different Indian fenugreek cultivars and studied for their functional, structural, thermal and rheological attributes. The highest yield (13.5%) was observed for cultivar RMT-365. All galactomannans depicted good water and oil holding capacities ranging from 2009 ± 5.5 to 2099.9 ± 2.5% and 523.5 ± 3.5 to 553.0 ± 2.0%, respectively. DSC thermograms of FG revealed the presence of one endothermic and one exothermic peak. For endothermic transition of gums from different cultivars, enthalpy change (Δ Ha) ranged from 234.2 to 351.8 J/g while for exothermic transition, Δ Ha values ranged from 72.0 to 102.1 J/g, much lower as compared with endothermic peak. The effect of variable shear rate on viscosity of 1% FG solutions showed their shear thinning behaviors for all the cultivars, whereby the viscosity decreased with increasing shear rate. Frequency sweep tests indicated typical viscoelastic fluid behavior for all the gum solutions. Increase in the magnitude of G' and G″ of FG solutions was observed with an increase in frequency. A detailed understanding of different chemical, functional and thermal properties of FG could surely enlarge the radius of its application and eventually aid in its utilization in different food, pharma and cosmetic products.

Inulinase production and mathematical modeling from carob extract by using Aspergillus niger.

The main objectives of the study were to produce inulinase from carob extract by Aspergillus niger A42 (ATCC 204447) and to model the inulinase fermentation in the optimum carob extract-based medium. In the study, carob extract was used as a novel and renewable carbon source in the production of A. niger inulinase. For medium optimization, eight different variables including initial sugar concentration (°Bx), (NH4 )2 HPO4 , MgSO4 .7H2 O, KH2 PO4 , NH4 NO3 , yeast extract, peptone, and ZnSO4 .7H2 O were employed. After fermentations, optimum medium composition contained 1% yeast extract in 5°Bx carob extract. As a result of the fermentation, the maximum inulinase activity, maximum invertase-type activity, I/S ratio, maximum inulinase- and invertase-type activity rates, maximum sugar consumption rate, and sugar utilization yield were 1507.03 U/ml, 1552.86 U/ml, 0.97, 175.82 and 323.76 U/ml/day, 13.26 g/L/day, and 98.52%, respectively. Regarding mathematical modeling, the actual inulinase production and sugar consumption data were successfully predicted by Baranyi and Cone models based on the model evaluation and validation results and the predicted kinetic values, respectively. Consequently, this was the first report in which carob extract was used in the production of inulinase as a carbon source. Additionally, the best-selected models can serve as universal equations in modeling the inulinase production and sugar consumption in shake flask fermentation with carob extract medium.

Evaluation of the mucoadhesive strengths of Abelmoschus esculentus and Irvingia gabonensis gums for possible application in veterinary vaccine delivery: the effect of extraction methods.

This study evaluates the effects of different gum extraction methods on the mucoadhesive strengths of Abelmoschus esculentus (AE) and Irvingia gabonensis (IG) gums and the release of vaccine antigen in vaccine-gum formulations. AE and IG gums were extracted employing previously documented methods with acetone or sodium chloride (NaCl) and either oven-dried or freeze-dried. Gum extracts were analyzed for mucoadhesive strengths using a modified rotational cylinder method on animal mucosa. The time taken to detach from the mucosa was taken as the Peak Adhesion Time (PAT). The gum extracts were charged with Peste des petits ruminant vaccine and the antigen release was evaluated using agar gel immunodiffusion technique. The means of the PATS were analyzed using Mann-whitney t-test at p < .05. The NaCl extracted and freeze-dried IG gum showed sustained mean PATs of 1766 ± 73 s; 2116 ± 101 s; 7044 ± 117 s, while the oven-dried IG gum and both AE gums showed short-lived average PATs. Vaccine-gum formulations of IG at ratios 2:1, 1:1 & 1:2 had strong positive reactions while only that of AE at 2:1 showed a strong positive reaction. This study shows that NaCl extracted and freeze-dried IG gum has immunomodulatory potential for mucoadhesive vaccine delivery in ruminants.

Flaxseed gum: Extraction, bioactive composition, structural characterization, and its potential antioxidant activity.

Flaxseed gum (FSG) is a heteropolysaccharide consist of neutral and acidic components that makes up approximately 8% of seed mass. FSG was extracted from mixture of brown and golden varieties of flaxseeds by hot water extraction method. The molecular weight distribution, monosaccharide analysis, chemical composition, and surface morphology of FSG were scrutinized in the current study to get a better insight regarding this important polysaccharide. The average molecular weight was recorded as 1,322 kDa with a polydispersity ratio of 1.6 for Mw/Mn and 2.4 for Mn/Mz. High-performance liquid chromatography (HPLC) screening revealed that extracted FSG was comprised of rhamnose, arabinose, mannose, glucose, fucose, xylose, galactose, glucosamine, glucuronic acid, and galacturonic acid, of which mannose and glucosamine have not been reported previously. The antioxidant activities of FSG measured as DPPH, ABTS, reducing power, and total antioxidant activity clearly demonstrated the antioxidant potency of FSG. Fourier-transform infrared spectroscopy (FTIR) and the Nuclear magnetic resonance (NMR) (1 H, 13 C) s pectra ratified the presence of functional groups typical for polysaccharide. PRACTICAL APPLICATIONS: Flaxseed gum is a natural carbohydrate polymar. This study provides useful information regarding antioxidant potential, chemical, and structural characterization of FSG. The availability of a gum is fully characterized with bioactive composition, structural features, and antioxidant potential provides a toolset for the practical application in the food or drug industry.

Fenugreek seed gum: Biological properties, chemical modifications, and structural analysis- A review.

Fenugreek is a leguminous plant belongs to the family Fabaceae, which is extensively cultivated as a semiarid crop in Northern Africa, the Mediterranean, India, and Canada. In the present review paper, first we summarized the extraction, purification, chemical composition, molecular structure, and rheological behavior of the mucilages isolated from Fenugreek seeds (FSG), and then their functional properties presented to elucidate the potential application of this traditional source of hydrocolloids in food, pharmaceutical, and other industries. To date, there is no technique that can successfully remove the attached protein from FSG. From a structural point of view, galactose and mannose are the most abundant polysaccharide in FSG composition, suggesting a galactomannan-like structure. FSG is the most soluble of the seed gums. FSG solutions at various temperatures and concentrations showed a time-dependent shear thinning behavior. Furthermore, these hydrocolloids can be employed for the fabrication of eco-friendly packaging systems. Antioxidant capacity and anti-fungi activity of FSG has been proved in different studies. In conclusion, industrial applications of FSG are possible due to its strong thickening properties. Additionally, FSG has an excellent emulsification capacity, which enables its application in the food, cosmetic and/or pharmaceutical industries.

Molecular, rheological and physicochemical characterisation of puka gum, an arabinogalactan-protein extracted from the Meryta sinclairii tree.

A water-soluble polysaccharide (type II arabinogalactan-protein) extracted from the gum exudate of the native New Zealand puka tree (Meryta sinclairii), was characterised for its molecular, rheological and physicochemical properties. In 0.1 M NaCl, the weight average molecular weight (Mw) of puka gum is 5.9 × 106 Da with an RMS radius of 56 nm and z-average hydrodynamic radius of 79 nm. The intrinsic viscosity of the polysaccharide is 57 ml/g with a coil overlap concentration 15% w/w. Together, the shape factor, p, of 0.70 (exponent of RMS radius vs. hydrodynamic radius), Smidsrød-Haug's stiffness parameter B of 0.031 and Mark-Houwink exponent α of 0.375 indicate that the polysaccharide adopts a spherical conformation in solution, similar to gum arabic. The pKa is 1.8. The polysaccharide exhibits a Newtonian to shear-thinning behaviour from 0.2 to 25% w/w. Viscosity of the polysaccharide (1 s-1) decreases with decreasing concentration, increasing temperature, ionic strength, and at acidic pH.

Sources, structure, properties and health benefits of plant gums: A review.

This article has been developed with the aim of reviewing the different sources, structure, extraction, composition, properties and health benefits of plant gums. Gums are known for their multifarious uses in food industries like bakery, meat, fruit and vegetable. Those obtained from different sources exhibit differences in their chemistry. All have a rich nutritional profile and require different methods for extraction/purification. Most studies reveal fair flow characteristics of plant gums. The X-ray diffraction studies and scanning electron micrographs confer their amorphous nature. General appearance of plant gums varies from yellow-cream to whitish in color. Water absorption and swelling are two essential physicochemical properties of the plant gums owing to their hydrophilic nature. In spite of hydrophilicity, plant gums exhibit significant interfacial properties like emulsifying and foaming. Aqueous plant gum dispersions are acidic in nature and show great variations in their rheological behaviour. Thermal properties (DSC) of the plant gums reveal endothermic as well as exothermic transitions. Many gums obtained from botanical sources have proven health promoting benefits.

Effect of extraction temperature on rheological behavior and antioxidant capacity of flaxseed gum.

Soluble flaxseed gum (SFG) extracted at different temperatures (25, 40, and 60 °C) was analyzed in relation to the yield, polysaccharides and phenolics composition, surface charge, color, and rheological properties. The yield of SFG extract increased as the extraction temperature increased. The SFG xylan was the main component regardless the extraction temperature, but a reduction of substituents on the xylose chain was observed when increasing the extraction temperature. The phenolic compounds were also affected by the extraction temperature, influencing the antioxidant capacity of the gum. For all the extraction temperatures, SFG aqueous solutions showed a shear time-independent and shear-thinning behavior. Furthermore, oscillatory measurements showed a prevailing viscous character, but the decrease of the extraction temperature resulted in an increase of both G' and G". Therefore, SFG extracted at low extraction temperatures showed higher viscous and elastic properties, while high extraction temperatures increased the antioxidant activity.