65 research outputs found

    Degradative actions of microbial xylanolytic activities on hemicelluloses from rhizome of Arundo donax.

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    Polysaccharidases from extremophiles are remarkable for specific action, resistance to different reaction conditions and other biotechnologically interesting features. In this article the action of crude extracts of thermophilic microorganisms (Thermotoga neapolitana, Geobacillus thermantarcticus and Thermoanaerobacterium thermostercoris) is studied using as substrate hemicellulose from one of the most interesting biomass crops, the giant reed (Arundo donax L.). This biomass can be cultivated without competition and a huge amount of rhizomes remains in the soil at the end of cropping cycle (10–15 years) representing a further source of useful molecules. Optimization of the procedure for preparation of the hemicellulose fraction from rhizomes of Arundo donax, is studied. Polysaccharidases from crude extracts of thermophilic microorganisms revealed to be suitable for total degradative action and/or production of small useful oligosaccharides from hemicelluloses from A. donax. Xylobiose and interesting tetra- and pentasaccharide are obtained by enzymatic action in different conditions. Convenient amount of raw material was processed per mg of crude enzymes. Raw hemicelluloses and pretreated material show antioxidant activity unlike isolated tetra- and pentasaccharide. The body of results suggest that rhizomes represent a useful raw material for the production of valuable industrial products, thus allowing to increase the economic efficiency of A. donax cultivation

    Determination of flavor-potentiating compounds in different Italian tomato varieties

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    Umami taste, known as appetizing sensation, is mainly imparted by monosodium glutamate (MSG, the first identified umami factor) in synergistic combination with some 5 ' ribonucleotides such as inosine 5 '-monophosphate, IMP, guanosine 5 '-monophosphate, GMP, and adenosine 5 '-monophoshate, AMP. The level of free glutamic acid in tomatoes is higher than in other vegetables or fruits and increases with ripening and industrial processing. In addition, due to the presence of bioactive metabolites, tomatoes and tomato-based products are among the most consumed healthy food items. The levels of the major umami compounds of tomato, that is, glutamate and 5 '-ribonucleotides (GMP and AMP) were assessed in different parts (skin, outer flesh, and inner pulp) of known tomato varieties from southern Italy: San Marzano Originale, San Marzano 245, Black Tomato, Corbarino Corbara, Corbarino Nocera, and Superpomodoro (tomato hybrid). Such varieties were also investigated for their antioxidant properties through DMPD, DPPH, and ABTS assays, with San Marzano Originale showing the highest antioxidant power both in lipophilic and methanolic fractions. The concentration of umami compounds in tomato differs with the part of the fruit analyzed and is greatly dependent on the variety, being Corbarino Nocera the cultivar richest in glutamate and Superpomodoro in ribonucleotides. As for nutritional aspect, results confirm the great nutraceutical feature of San Marzano tomato, the most known variety used in industrial processes. Practical applications This study was planned to develop a method to quantify the major umami compounds that strongly influence the organoleptic properties of many different tomato varieties. It is known that the sensory quality of fruits and vegetables is an important factor in consumer's choice. The analytical methods described here enabled the evaluation of the glutamate and 5 '-ribonucleotides contents in six selected varieties of tomato from Campania region, and can be easily used to determine the sensory profile of commercial varieties, for example, those perceived as not very tasteful by consumers

    Comparative fatty acid profiling of edible fishes in Kuala Terengganu, Malaysia.

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    The aim of this study was to compare the relative nutritional benefit of edible Malaysian fishes from the coast of Terengganu in Malaysia, as well as to perform a taxonomical characterization and metal assessment. Discrimination between species was carried out by a morphological and molecular approach, by evaluating the total concentrations of metals by ICP-MS analyses and the fatty acids (FA) composition using the GC–MS approach on the fish fillet tissues. The taxonomical studies detected fishes of 11 families and 13 species. The heavy metal assessment showed that all detected elements did not exceed the regulatory limit stated by Malaysian Food Regulations. The proportion of saturated fatty acids (SFA) ranged from 33 to 58.34%, followed by the polyunsaturated fatty acids (PUFA) values from 24 to 51.8%, and the lowest proportion was of monounsaturated fatty acids (MUFA), ranging from 12.7 to 35.9%. The ω-3/ω-6 PUFA and PUFA/SFA ratios were determined in the range 1.1 to 7.4 and 0.35 to 1.6, respectively. The C20:5 ω-3 and C22:6 ω-3 acids were detected at levels comparable to those found in the corresponding species from similar tropical marine ecosystems. The high FA values can be useful biochemical tools for comparing the relative nutritional benefits of these biodiverse and non-toxic edible Malaysian fishe

    Chemistry of tropical eucheumatoids: Potential for food and feed applications

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    The use of seaweeds as additives in animal nutrition may be a valid option to traditional feed as they represent a rich source of minerals, carbohydrates and antioxidants. The aim of this study was to analyze the chemical composition and in vitro antioxidant capacity of two tropical eucheumatoids, Kappaphycus alvarezii and Kappaphycus striatus, in Malaysian wild offshore waters. The chemical analysis was performed via inductively coupled plasma–optical emission spectroscopy for evaluating the concentration of toxic (Cd, Pb, Hg, As) and essential elements (Mn, Fe, Cu, Ni, Zn, Se); NMR spectroscopy was used for carrageenans investigation. Furthermore, the soluble and fat-soluble antioxidant capacities were determined by FRAP, DPPH and ABTS assays. The chemical analysis revealed a higher content of trace elements in K. alvarezii as compared to K. striatus, and both exhibited a high mineral content. No significant differences in metal concentrations were found between the two species. Both samples showed a mixture of prevailing κ-and t-carrageenans. Finally, the levels of soluble and fat-soluble antioxidants in K. alvarezii were significantly higher than in K. striatus. Our findings suggest that K. alvarezii could be used as a potential feed additive because of its favorable chemical and nutritional features

    Fatty Acids in Waste Tissues: The Nutraceutical Value of Gonads and Livers from the Moroccan Hypophthalmichthys molitrix and Cyprinus carpio Fishes

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    Fishes are an important component of human nutrition, mainly acting as source of essential fatty acids in the prevention of cardiovascular disorders. The increase in their consumption has led to a growth of fishes waste; therefore, the disposal and recycling of waste has become a key issue to address, in accordance with circular economy principles. The Moroccan Hypophthalmichthys molitrix and Cyprinus carpio fishes, living in freshwater and marine environments, were collected at mature and immature stages. The fatty acid (FA) profiles of liver and ovary tissues were investigated by GC-MS and compared with edible fillet tissues. The gonadosomatic index, the hypocholesterolemic/hypercholesterolemic ratio, and the atherogenicity and thrombogenicity indexes were measured. Polyunsaturated fatty acids were found to be abundant in the mature ovary and fillet of both species, with a polyunsaturated fatty acids/saturated fatty acids ratio ranging from 0.40 to 1.06 and a monounsaturated fatty acids/polyunsaturated fatty acids ratio between 0.64 and 1.84. Saturated fatty acids were found to be highly abundant in the liver and gonads of both species (range 30-54%), as well as monounsaturated fatty acids (range 35-58%). The results suggested that the exploitation of fish wastes, such as the liver and ovary, may represent a sustainable strategy for the achievement of high value-added molecules with nutraceutical potential

    Curcumin and cancer

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    Curcumin, a polyphenol extracted from Curcuma longa in 1815, has gained attention from scientists worldwide for its biological activities (e.g., antioxidant, anti-inflammatory, antimicrobial, antiviral), among which its anticancer potential has been the most described and still remains under investigation. The present review focuses on the cell signaling pathways involved in cancer development and proliferation, and which are targeted by curcumin. Curcumin has been reported to modulate growth factors, enzymes, transcription factors, kinase, inflammatory cytokines, and proapoptotic (by upregulation) and antiapoptotic (by downregulation) proteins. This polyphenol compound, alone or combined with other agents, could represent an effective drug for cancer therapy
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