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1.
This study aimed to evaluate the oils of soybean (S), papaya (Pa) and melon (Me) seeds and compounds oils SPa (80:20 w/w); SMe (80:20 w/w); and SPaMe (60:20:20 w/w/w) subjected to thermoxidation. Compound oils showed lower percentages of free fatty acids in relation to others, after 20 h. With the heating process, there was an increase in the quantity of saturated and monounsaturated acids. The quantity of carotenoids decreased, except in papaya seed oil that presented significant amount of carotenoids in 20 h. In relation the tocopherols, highlighted the presence of γ-tocopherol, except in the papaya oil. In 20 h, SMe and SPa still showed high amounts of tocopherols, with 76 and 85% of retention, respectively. With the thermoxidation, the amounts of phytosterols decreased. A great potential can be verified for the use of papaya and melon seed oils, in order to increase the oxidative stability of the soybean oil.  相似文献   

2.
The objective of this work was to evaluate the effect of six pretreatments on quality and nutritional contents of sliced Galega kale submitted to convective drying. Among all treatments, steam blanching was the most favourable, allowing improvements in retention of vitamin C, total antioxidant capacity and chlorophylls in comparison to the absence of pretreatment. Total phenolic losses were not reduced by steam blanching, but the retention was improved by combining this approach with a previous immersion in a metabisulphite solution. Moreover, steam blanching improved the colour parameters and appearance, providing a final dried product more similar to the fresh sample.  相似文献   

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4.
Adsorption isotherm was obtained to assess the hygroscopicity of yew wood using the Hailwood-Horrobin sorption theory. Yew wood showed very low EMC values in the whole range of relative humidities. An interesting point was that the adsorption isotherms of the yew wood were almost identical to that of pine wood modified with 15.8% acetic anhydride.  相似文献   

5.
The aim of this work was the formulation of adhesives for particleboards based on tannins extracted from industrial lignocellulosic wastes, namely chestnut shell, chestnut bur and eucalyptus bark. The interest was centred on the possibility of completely removing formaldehyde from adhesive formulations. For this, hardener alternatives to formaldehyde were used: tris(hydroxymethyl)nitromethane (TRIS), glyoxal (GLY) and hexametilentetramine (HEX). The influence of the type and concentration of the hardener and pH on adhesive gel time and pot-life were studied. A comparative structural characterization of the adhesives was performed by 13C-NMR spectroscopy. Thermomechanical analyses (TMA) tests were carried out as an indication of the final strength of the adhesive systems. Particleboards type 2 of interior use (EN 312) were manufactured with adhesives based on chestnut shell tannins alone or mixed with chestnut bur/or eucalyptus bark tannins. Free-formaldehyde was determined, and boards were prepared with TRIS, GLY and HEX tannin adhesives were classified as E0.  相似文献   

6.
Combination of dry and aqueous fractionation is investigated to obtain protein-rich fractions from quinoa in a milder and more sustainable way compared to conventional wet fractionation. Dry fractionation of quinoa involved milling and subsequent air classification, generating a protein-enriched embryo fraction. Subsequently, this fraction was milled, suspended, and further fractionated by aqueous phase separation. The efficiency of aqueous phase separation could be improved by addition of NaCl (0.5 M). Finally, the top aqueous phase was decanted and ultrafiltered, resulting in a protein purity of 59.4 w/dw% for the 0.5 M NaCl-protein solution and a protein yield (gram protein obtained/gram protein in seed) of 62.0 %. Having used 98 % less water compared to conventional wet extraction, the hybrid dry and aqueous fractionation is a promising method for industry to create value from quinoa in a more economic and sustainable friendly way while minimizing the impact on quinoa’s native protein functionality.  相似文献   

7.
The aim of this study was to determine the quality indices and assess the influence of diets supplemented with mussels from contaminated (MCont) and non-contaminated areas (MNCont) on some indices of protein and lipid metabolism in rats fed with cholesterol. A wide range of in vitro tests demonstrated that mussels from contaminated area have a higher content of proteins, lipids and higher antioxidant capability. In the in vivo experiment, 28 male Wistar rats were divided into 4 diet groups each of 7 and named Control, Cholesterol (Chol), Chol/MCont and Chol/MNCont. During 30 days of the experiment rats of all four groups were fed basal diet (BD), supplemented with 1% of Chol, 1% of Chol and 5.6% of mussel’s dry matter (DM) from contaminated and 1% Chol and 5.6% of mussel DM from non-contaminated areas for Chol/MCont and Chol/MNCont groups, respectively. At the end of the experiment, a high digestibility coefficient of DM and crude protein in the Chol/MCont and Chol/MNCont groups of rats was found: 93.56 and 93.87% and 91.64 and 91.36%, respectively, and the differences were not significant (P > 0.05). However, the protein efficiency ratio was significantly higher in the Chol/MCont and Chol/MNCont than in the Control and Chol diet groups. Also the level of nitrogen retention as shown by feces and urine examination was higher in the Chol/MCont and Chol/MNCont groups. Diet, supplemented with mussel dry matter from both contaminated and non-contaminated areas significantly hindered the rise in plasma lipids and also hindered the decrease in plasma antioxidant activity. Minor changes were fixed in the protein profile of rat’s plasma after both mussels’ diet. In conclusion, supplementation of diets, containing cholesterol with mussels’ DM from both contaminated and non-contaminated areas improves animals’ protein metabolism and positively affects plasma lipid profile and plasma antioxidant activity. Antioxidant tests can be used as an additional index for the quality of mussels.  相似文献   

8.
In order to evaluate the quality of maca samples, 15 batches of maca hypocotyls from different geographical origins were analyzed by using HPLC and liquid chromatography tandem mass spectrometry (LC-MS). Their glucosinolates (GLs) were identified, profiled, and quantified. Three aromatic GLs, glucosinalbin (GSB), glucotropaeolin (GTL), and glucolimnanthin (GLH), were identified from maca roots. It was found that the HPLC profiles of maca samples showed a similar qualitative pattern except for some differences in their contents. The amount ranges (μmol g?1, DW) of GSB, GTL, and GLH were 2.62–5.55, 12.99–57.12, and 3.15–12.12, respectively. Furthermore, a HCA (hierarchical clustering analysis) was used to classify the quality of maca samples according to their cultivated sources and GLs contents. The results showed that the combination of GSB, GTL, and GLH could be a marker for accurate determination and quality control of maca samples. It was concluded that the multi-component analysis in combination with HCA could be a supplement to assess the quality of maca materials.  相似文献   

9.
The volatile composition of the essential oil from fresh gamguk (Chrysanthemum indicum) flowers was investigated. The volatile constituents were extracted by the hydro distillation method. Volatile compositional changes of gamguk prepared via different drying methods (shade- and freeze-drying methods) were also determined. Total 36, 63, and 55 volatiles constituents were confirmed in the essential oil from fresh and shade-, and freeze-dried flowers. Ketones were predominant in the volatiles of gamguk flowers (%): fresh, 43.8; shade dried, 30.3; and freeze dried, 36.1. Camphor was the most abundant volatile component in all samples, and the content of borneol was also remarkable. The content of camphor was higher in fresh sample than those of dried samples while borneol concentration was significantly increased in the dried samples.  相似文献   

10.
The identification and characterization of Bacillus mojavensis KJS-3 was performed by in vitro tests. A 16S rDNA sequence and phylogenetic tree demonstrated that this isolate belongs to the B. mojavensis group. B. mojavensis KJS-3 supplies nutrients by synthesizing several vitamins. B. mojavensis KJS-3 produces α-amylase and protease. B. mojavensis KJS-3 is cultured well under aerobic conditions without gas production. B. mojavensis KJS-3 allows for assimilation of cholesterol and bile salt hydrolase activity. Finally, adhesion experiments using Caco-2 cells revealed that the adherence of B. mojavensis KJS-3 to Caco-2 cells was approximately 51.2±8.14%.  相似文献   

11.
Starch retrogradation in plantain starch was studied by an enzymatic method and X-ray diffraction analysis. The enzymatic method and X-ray diffraction gave comparable results. Retrograded starch (RS3) and physically trapped starch (RS1) contents of plantain foods were subsequently determined by the enzymatic method. RS3 content of 5.0 ± 0.9 to 13.2 ± 3.0 g/100 g dry weight basis was obtained for unripe samples while a value ranging from 0.9 ± 0.4 to 2.5 ± 0.9 g/100 g was obtained for ripe samples. Retrogradation increased slowly digestible starch (SDS) and physically inaccessible starch (RS1) portions in some of the samples but not in others. Retrogradation resulted in an increase in the quantity of SDS for ripe plantain samples. In unripe plantain samples cooked without salt, there was a significant increase (p ≤ 0.05) in the value of RS1 from 4.6 ± 3.6 to 7.7 ± 2.0 g/100 g after 48 h of cold storage but no significant change for samples cooked with salt.  相似文献   

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Seeds from fruits such as Citrullus (C.) lanatus (watermelon) and Limonia (L.) acidissima (wood apple) are not commonly utilized but could be suitable in numerous food formulations. It was shown that the protein content of defatted seed flours was 71.38 and 49.51 % and that these contained considerable amounts of minerals such as Na, Mn, Mg, K, Cu, Fe and Zn. The defatted L. acidissima seed flour was superior to C. lanatus in essential amino acids. The flours obtained from both seeds were also evaluated for functional properties and characterized by X-ray diffraction, differential scanning calorimeter and scanning electron microscope (SEM). Amorphous nature was observed in defatted C. lanatus and L. acidissima flours due to the low percentage of degree of crystallinity. Spherical morphologies were observed through SEM. The exothermic peak was recorded in defatted C. lanatus and L. acidissima flour.  相似文献   

14.
Nutritional and health-related compounds of alfalfa, wheat and soybean seeds dried by new drying process called the DIC process (controlled instantaneous pressure release) were evaluated, before and after sprouting. Vitamins (A, B1, B2, B6, C and E), minerals (Fe, Mg, Ca, K, Mn, Na, Cu and Zn) and phytoestrogens (genistein and daidzein ) content were determined. Alfalfa, soybean and wheat seeds dried by DIC showed similar content of biological compounds to seeds dried by traditional processes. Sprouting DIC-seeds significantly increased the levels of vitamins, minerals and phytoestrogens, improving their nutrititional value and health quality compared to fresh products. The increase of 1250-fold and 10-fold of the initial vitamin A and vitamin C content, respectively, of alfalfa seeds due to sprouting is remarkable. Sprouts from DIC-seeds showed a significantly higher vitamin A content than sprouts obtained from seeds dried by other methods. Soybean sprouts obtained from DIC-seeds showed a significant increase in free phytoestrogens, quantified as genistein (70.34LJ.8 mg kg-1 d.w.) and daidzein (109.17.3ᆥ.3 mg kg-1 d.w.).  相似文献   

15.
This study assessed the changes of antioxidant activity and bioactive compounds of crude and refined kenaf seed oil during accelerated storage at 65°C for 24 days. 2,2-Diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assays were used to determine their antioxidant activity. The changes of phenolic, tocopherol, and phytosterol contents during the storage were also studied. The phenolic content and antioxidant activity of refined oil were significantly lower than those of crude oil after the accelerated storage. There was a decrease of 72.5% tocopherol content and 31.1% phytosterol content in the crude oil and a decrease of 67% tocopherol content and 12.1% phytosterol content in the refined oil during the accelerated storage. There was no significant difference in tocopherol and phytosterol contents for crude and refined oils after the storage. The rate of degradation of tocopherol and phytosterol contents in refined oil was slower than that in crude oil during the storage.  相似文献   

16.
The various extracts from chamdanggui (Angelica gigas Nakai) and sogdan (Phlomis umbrosa Turcz) were evaluated for estrogenic activity and characterized according to HPLC profile. Chamdanggui and sogdan were individually extracted with 4 solvents (hot water, 70% ethanol, n-butanol, and dichloromethane) of differing polarities. Estrogenic activity was determined by E-screen using an estrogen-dependent MCF-7 BUS cell. Although almost all extracts showed estrogenic effects in a concentrationdependent manner, the hot water extract from chamdanggui (250 μg/mL) had the higher effect (138%). Among 90 fractions using HPLC separation of the hot water extract from chamdanggui, fraction 21 and 28 produced the highest estrogenic effects of 178 and 163% at 10 μg/mL, respectively. The results imply that the hot water extract from chamdanggui could be useful as an alternative hormone replacement therapy.  相似文献   

17.
Monascus, fermented rice (red mold rice), has been found to reduce the serum total cholesterol and triglyceride due to presence of lovastatin. Lovastatin acts as an inhibitor of 3-hydroxy-3-methyl glutaryl coenzyme A reductase. Coculture of Monascus purpureus MTCC 369 and Monascus ruber MTCC 1880 was used to produce red mold rice by solid-state fermentation. Optimization of different fermentation process parameters such as temperature, fermentation time, inoculum volume, and pH of the solid medium was carried out by Box–Behnken’s factorial design of response surface methodology to maximize lovastatin concentration in red mold rice. Maximum lovastatin production of 2.83 mg/g was predicted at 14th day in solid medium under optimized process condition.  相似文献   

18.
Black chokeberry juice (Aronia melanocarpa, Elliot), blackcurrant juice (Ribes nigrum, Ben Lomond) and α-tocopherol were found to protect phosphatidyl choline against oxidation in a peroxidating liposome system as evidenced by lag phases for formation of conjugated dienes. When present together, black chokeberry juice and α-tocopherol showed a clear synergistic effect on the length of the lag phase, while effects of blackcurrant juice and α-tocopherol were additive. The concentration of total phenolics in black chokeberry juice was six times higher than in blackcurrant juice (gallic acid equivalents). Ascorbic acid corresponded to 1% of total phenolics in black chokeberry juice and 10% in blackcurrant juice. Based on the length of the lag phase, the phenolics present in black chokeberry were on an average, twice efficient as scavengers of lipid peroxyl radicals as phenolics in blackcurrant. Black chokeberry was by HPLC analysis of peroxidating liposomes, in contrast to blackcurrant, found to protect α-tocopherol efficiently against oxidation to the end of the lag phase. The phenolics present in black chokeberry juice were concluded to be more efficient in regenerating or protecting α-tocopherol than ascorbic acid or the phenolics in blackcurrant. As for the phenolics, this was further evidenced by ranking of their radical scavenging activity as studied by ESR-spectroscopy.  相似文献   

19.
Complementary DNA clones encoding trypsins were isolated from pyloric ceca of cold-adapted fish, walleye pollock (Theragra chalcogramma) (WP-T) and Arctic cod (Boreogadus saida) (AC-T). The isolated full-length cDNA clones of WP-T and AC-T were 852 and 860 bp, respectively, and both cDNAs were contained an open reading frame of 726 bp. WP-T and AC-T seemed to be synthesized as preproenzyme that contains a signal peptide, an activation peptide, and a mature trypsin. Although the amino acid sequence identities of WP-T and AC-T to that of bovine trypsin were 64 and 63%, respectively, they completely conserved the structural features for catalytic function of trypsin. On the other hand, WP-T and AC-T possessed the four Met residues (Met135, Met145, Met175 and Met242) in their molecules and the deletion of Tyr151 and substitution of Pro152 for Gly in their autolysis loops when aligned with the sequences of tropical-zone fish and bovine trypsins. In addition, the contents of charged amino acid residues at the N-terminal regions (positions 20–50) of WP-T and AC-T were extremely higher than those of other fish and bovine trypsins. Moreover, one amino acid (Asn72) and two amino acids (Asn72 and Val75) coordinating with Ca2+ in bovine trypsin were exchanged for another amino acids in WP-T (His) and AC-T (His and Glu), respectively, and the contents of negative charged amino acids at their Ca2+-binding regions were lower than those of tropical-zone fish and bovine trypsins. Therefore, it was considered that these structural characteristics of WP-T and AC-T are closely related to their lower thermostability.  相似文献   

20.
The prevalence, genetic diversity, and antibiotic susceptibility of Cronobacter species (Enterobacter sakazakii) isolated from sunshik products, its ingredients, and root vegetable farm’s soils were investigated to analyze main reservoirs and contaminated sources of Cronobacter spp. Cronobacter spp. was isolated from 9 of 15 sunshik products, 26 of 72 its ingredients, and 2 of 39 soils. The root vegetables such as sweet potato and carrot showed higher contamination rate (70%) than the other sunshik ingredients. All isolates showed 929 bp band amplified from 16S rRNA and resistant to ampicillin, amoxicillin/clavulanic acid, and cefazolin. All isolates showed diverse random-amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) band patterns. However, 3 cases of RAPD banding patterns between clinical strains and isolates from sunshik products and root vegetables (yam, carrot) were related with similarities level of 80%. These studies indicated that root vegetables can be an important contamination source of Cronobacter spp. in sunshik products. Thus, the preparation of root vegetables for manufacturing sunshik products used as a weaning diet was handled with more care than the other sunshik ingredients.  相似文献   

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