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1.
Ten popular species of both edible and medicinal Korean mushrooms were analysed for their free amino acids and disaccharides. The average total free amino acid concentration was 120.79 mg g−1 in edible mushrooms and 61.47 mg g−1 in medicinal mushrooms, respectively. The average total of free amino acids for all mushrooms, edible mushrooms and medicinal mushrooms was 91.13 mg g−1. Agaricus blazei (227.00 mg g−1) showed the highest concentration of total free amino acids; on the other hand, Inonotus obliquus (2.00 mg g−1) showed the lowest concentration among the 10 species of mushrooms. The average total carbohydrates concentration was 46.67 mg g−1 in the 10 species of mushrooms, where the edible mushrooms contained 66.68 mg g−1 and the medicinal mushrooms contained 26.65 mg g−1. The carbohydrates constituents of the 10 mushroom species were mainly mannose (36.23%), glucose (34.70%), and xylose (16.83%).  相似文献   

2.
Fructose, glucose and sucrose, as the major soluble sugars and citric and malic acids, as the major organic acids, were identified and determined in kale (Brassica oleraceae L. var. acephala DC., black cabbage) leaves. Fructose was the predominant sugar (2011 mg 100 g−1 dry wt) identified, followed by glucose (1056 mg 100 g−1 dry wt) and sucrose (894 mg 100 g−1 dry wt). The contents of citric and malic acids were at 2213 and 151 mg 100 g−1 dry wt in the leaves. The 16:0, 18:2n − 6 and 18:3n − 3 fatty acids were the most abundant fatty acids in the leaves. Considering the level of these fatty acids, 18:3n − 3 was found to be the highest (85.3 μg g−1 dry wt), contributing 54.0% of the total fatty acid content. Linoleic acid (18:2n − 6), being the second most abundant fatty acid was present at 18.6 μg g−1 dry wt, contributing 11.8% of the total fatty acid content. In the seed oil of kale, 22:1n − 9 was the most abundant fatty acid (4198 μg g−1 dry wt, 45.7%), with 18:2n − 6 (1199 μg g−1 dry wt, 12.3%) and 18:1n − 9 (1408 μg g−1 dry wt, 14.8%) being the second next most abundant fatty acids. The most abundant amino acid was glutamic acid (Glu) which was present at 33.2 mg g−1 dry wt. Aspartic acid, which was the second most abundant amino acid, was present at 27.6 mg g−1 dry wt and accounted for 10.2% of the total amino acid content of kale leaf. The amino acid content was assessed by comparing the percentages of the essential amino acids in kale leaf versus those of a World Health Organization (WHO) standard protein. The protein of kale leaf compares well with that of the WHO standard. Only one amino acid, lysine, had a score that fell below 100%; the lysine score of kale leaf was 95%. This study attempts to contribute to knowledge of the nutritional properties of the plant. These results may be useful for the evaluation of dietary information.  相似文献   

3.
Cell walls were isolated from flesh and skin of five plum varieties corresponding to three species (Prunus domestica L., Prunus salicina Lindl. and Prunus insititia Lindl.) using the alcohol-insoluble solids (AIS) procedure. Yields varied from 83 to 114 g kg−1 dry weight in the flesh and from 192 to 361 g kg−1 dry weight in the skins. Their main sugars were uronic acid (224–322 mg g−1 AIS), cellulosic glucose (139–170 mg g−1 AIS), galactose and arabinose. Galactose and arabinose ratio were variable between the varieties. The degrees of methylation were high (62–84).  相似文献   

4.
Various solvent extracts of Kappaphycus alvarezii, an edible red seaweed (family Solieriaceae) were screened for total phenol content and antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferrous ion chelating activity, reducing power and antioxidant activity assays in a linoleic acid system with ferrothiocyanate reagent (FTC). The total phenol content of different extracts of K. alvarezii varied from 0.683 ± 0.040% to 2.05 ± 0.038%. The radical-scavenging activity of ethanol extract was, as IC50 3.03 mg ml−1, whereas that of the water extract was IC50 4.76 mg ml−1. Good chelating activity was recorded for methanol extract (IC50 3.08 mg ml−1) wherein 67.0 ± 0.924% chelation was obtained using 5.0 mg ml−1 of extract. The reducing power of the samples was in the following order: BHT > methanol > ethanol > ethyl acetate > water > hexane. But, in the linoleic acid system, the ethanol extract proved superior to the synthetic antioxidants butylated hydroxytoluene (BHT). Hence, these extracts could be considered as natural antioxidants and may be useful for curing diseases arising from oxidative deterioration.  相似文献   

5.
The identification and quantification of carotenoids has been carried out on tropical and non tropical fruits because of two important carotenoid's properties: as antioxidant compounds having a prevention role in some diseases, and as a source of provitamin A needed for a good human nutrition. This study aimed to identify carotenoids present during different steps for producing flour from Costa Rican peach-palm fruit (Bactris gasipaes H.B.K). Nine carotenoids were tentatively identified and quantified by HPLC-DAD in raw pulp, and 14 were detected in cooked pulp, the additional five being products of isomerization and hydroxylation of carotenoids in the raw pulp. The flour contained 13 carotenoids, one less (all-trans-??-criptoxanthin) than in cooked pulp, with the main one being all-trans ??-carotene. This carotenoid was also present in raw pulp at a concentration of 96.0 ± 1.7 ??g equiv. of ??-carotene g−1 dw. The concentration decreased significantly (P < 0.05) during cooking and drying to reach a final concentration of 33.3 ± 1.0 ??g equiv. ??-carotene g−1 dw in the flour. Flour production reduced (P < 0.05) the total carotenoid content from 373.4 to 237.7 ??g of ??-carotene g−1 dw, with a final retention rate of 63.7% by the end of the process. Moreover, 9 of the 14 carotenoids account for high levels of provitamin A, which, even so, had decreased from 2723 retinol equivalents (RE) 100 g−1 in raw pulp to 1614 RE 100 g−1 in cooked pulp and 1289 RE 100 g−1 in flour. Provitamin A level is still high when compared to other common provitamin A sources. Our study shows that while there is a change in the levels and profile of carotenoids during the peach-palm flour process, and a reduction of provitamin A value, peach-palm fruit is a great source of bioactive compounds.  相似文献   

6.
The contents of As, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, and Zn in eleven fruiting bodies of Boletus tomentipes were determined. The results showed the values of the studied elements decreased in the order: Mg (208–279 mg kg−1) > Fe (106–137 mg kg−1) > Mn (29.5–46.8. mg kg−1) > Zn (18.7–23.1 mg kg−1), > Cu (11.4–15.8 mg kg−1) > Cr (3.36–4.78 mg kg−1) > Pb (1.38–3.88 mg kg−1) > Ni (1.68–3.01 mg kg−1) > Cd (0.16–0.32 mg kg−1) > As (0.10–0.24 mg kg−1) > Hg (<0.06 mg kg−1).  相似文献   

7.
Total capsaicinoids, colour and volatile compounds of 10 Habanero chilli pepper (Capsicum chinense Jack.) cultivars grown in Yucatan, grouped by their colours: four red, five orange and one brown, were determined. The content of capsaicinoids, responsible for the pungency of chilli peppers, varied between 41.8 and 65.9 mg g−1 dry fruit. Mean concentration of orange cultivars was 55.0 mg g−1, while red cultivars had 45.0 mg g−1 dry fruit, indicating that the first ones are more pungent. The composition of volatile compounds of the Habanero chilli peppers differs clearly for the different cultivars. Orange and brown cultivars have in general higher amounts of esters, with their fruity odour notes, than red cultivars. These differences are reflected in the amount of total volatiles, which is higher in orange and brown cultivars in comparison with red cultivars. From these results it can be concluded that orange and brown cultivars are better in terms of their flavour-relevant chemical composition than red cultivars.  相似文献   

8.
Minor carbohydrates present in carrot (Daucus carota L.) have been studied by GC–MS analysis of their trimethylsilyl derivatives because of their remarkable role in a variety of biological functions. Scyllo-inositol and sedoheptulose (d-altro-2-heptulose), identified for the first time in this paper were present in all the carrots analysed in concentrations ranging 1.5–5.8 and 1.4–24.6 mg g−1 dried weight, respectively. Other minor carbohydrates detected in carrot were myo- inositol (2.2–9.8 mg g−1) and mannitol (traces-1.3 mg g−1). Whereas small amounts (close to 2 mg g−1) of scyllo-inositol were experimentally determined in other vegetables from the Apiaceae family (parsley, coriander and fennel), sedoheptulose was only detected at trace levels.  相似文献   

9.
The shelf life of red mullet and goldband goatfish during ice storage were studied in terms of sensory, microbiological and chemical changes. The sensory acceptability limit was 8 days for goldband goatfish (Upeneus moluccensis) and 11 days for red mullet (Mullus barbatus) stored in ice. The TVC level was correlated with sensory assessment. The TVC exceeded 7 log cfu g−1 after 8 days for goldband goatfish, and 11 days for red mullet. At the end of storage period, pH, TVB-N, TBA, FFA and PV for red mullet were 7.84, 47.19 mg/100 g, 0.69 mg MA kg−1, 1.17% oleic acid and 1.58 meq O2/kg and for goldband goatfish they were 7.53, 43.97 mg/100 g, 0.74 mg MA kg−1, 1.62% oleic acid and 1.68 meq O2/kg, respectively. In red mullet, agmatine, serotonin, histamine and dopamine became the dominant amines, reaching 7.30, 5.97, 2.52 and 2.31 mg/100 g, respectively. Also the dominant amines for goldband goatfish were 4.37, 3.88, 3.38 and 2.00 mg/100 g for histamine, agmatine, dopamine and putrescine, respectively.  相似文献   

10.
The first chemical characterization of abbamele, a traditional honey decoction from Sardinia (Italy) is hereby reported. Water content (from 17.7% to 27.7%), electrical conductivity (from 0.19 to 0.81 mS cm−1), pH (from 3.21 to 3.92), free acidity (from 26.1 to 87.6 meq kg−1), invertase activity (from 0 to 1.02 U kg−1), 5-(hydroxymethyl)-2-furaldehyde, HMF (from 881 to 4776 mg kg−1), total polyphenols (from 188 to 984 mg kg−1) and free amino acid contents of thirteen abbamele samples, from industrial and traditional producers, were obtained in an attempt to compare this traditional product with honey and to study the relationship between its main features and the production procedures. The long thermal treatment involved in the production of abbamele has been identified as the main cause of very low (or absent) invertase activity and free amino acid content as well as the very high content of HMF.  相似文献   

11.
The ethyl acetate and methanol extracts from 16 Salvia L. species were screened for their inhibitory activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase, and tyrosinase; the enzymes linked to neurodegeneration. Their antioxidant activity was also tested using DPPH radical scavenging, metal-chelation, and ferric-reducing antioxidant power (FRAP) assays. Total flavonoid content of the extracts was determined by AlCl3 reagent, while HPLC technique was applied for analysis of various phenolic acids in the extracts. The extracts exerted weak cholinesterase and tyrosinase inhibition, and remarkable inhibition against lipoxygenase (13.07 ± 2.73-74.21 ± 5.61%) at 100 μg ml−1. The methanol extracts showed higher antioxidant activity in DPPH radical scavenging and FRAP assays. The extracts were analyzed for their gallic, protocateuchic, p-hydroxy-benzoic, vanillic, caffeic, chlorogenic, syringic, o- and p-coumaric, ferulic, rosmarinic, and tr-cinnamic acid contents and the methanol extract of Salvia ekimiana (153.50 mg 100 g−1) was revealed to be the richest in terms of rosmarinic acid.  相似文献   

12.
Agrocybe cylindracea (DC: Fr.) Mre. was available in the form of fruit bodies, mycelia and fermentation filtrate. From these three forms, hot-water extracts were prepared and their antioxidant properties were studied. Antioxidant activities of hot-water extracts from fruit bodies, mycelia and filtrate were 63.6%, 81.6% and 56.8% at 20 mg ml−1, respectively. EC50 values in reducing power were 2.72, 3.97 and 3.09 mg ml−1 whereas those in scavenging abilities of 1,1-diphenyl-2-picrylhydrazyl radicals were 0.62, 1.66 and 0.82 mg ml−1 for fruit bodies, mycelia and filtrate, respectively. At 20 mg ml−1, the scavenging abilities of hydroxyl radicals were 80.1%, 57.0% and 54.3% for fruit bodies, mycelia and filtrate, respectively. With regard to EC50 values in chelating abilities on ferrous ions, the hot-water extract from filtrate was better than that from mycelia. Total phenols were the major naturally occurring antioxidant components found in hot-water extracts and in the range of 23.74–30.16 mg g−1. From EC50 values obtained, it can be concluded that hot-water extracts from three forms of A. cylindracea were good in antioxidant properties.  相似文献   

13.
Phytic acid or phytate is a chelating agent, which is involved in binding minerals (such as K+, Ca2+, Zn2+, Fe2+, etc.) and making them unavailable for dietary absorption. It is also involved in forming complexes with protein, making protein less soluble, and affecting enzymatic degradation, gastric absorption, and malting processes. The phytic acid and protein contents of barley grains are influenced by genetic and environmental factors. This study investigated differences in phytic acid and protein contents in grains of 100 barley (Hordeum vulgare L.) genotypes or cultivars. Eight barley cultivars were selected and grown at seven locations for two years to study the effects of genotypic and environmental factors on phytic acid content (PAC) and its relation to malt quality. The phytic acid contents of 100 barley genotypes ranged from 3.85 mg g−1 to 9.85 mg g−1, with a mean of 7.01 mg g−1. The effects of cultivars, locations, time and their interactions were highly significant, but the variation was mainly attributed to the environment (location and time). The correlation between grains phytic acid and protein content was significant and positive. Whereas, the correlation between grain phytic acid content and malt extract was significant and negative. The relationship between phytic acid and protein contents of barley is important as it affects the malting process, malt yield and quality, and final beer quality. Barley grain for malting and feed uses should have low phytic acid content.  相似文献   

14.
Ethyl carbamate (EC), which is probably carcinogenic to humans, can be produced during the alcoholic fermentation of sugar-cane juice to give cachaça. The stages to produce cachaça are obtainment of sugar-cane juice, sugar-cane fermentation to wine, and obtainment of distilled fractions and residue. In order to investigate the presence of EC in the wine and in the fractions of the distillation process, as well as in the vinasse (the residue left after distillation), gas chromatography–mass spectrometry was employed. After the fermentation phase, the wine showed an average content of 122 mg L−1 of EC. Average EC content in distilled fractions was 59.7 mg L−1 for head, 52 μg·L−1 for heart and 1.57 mg L−1 for tail. EC content was 53.1 mg L−1 for vinasse. The results showed that it is essential to separate the head and tail fractions to ensure cachaça quality, with respect to EC content.  相似文献   

15.
Studies were conducted in the early season of 2002 and 2003 at the Teaching and Research Farm, Obafemi Awolowo University, Ile-Ife, Nigeria to evaluate the effect of phosphorus (P) on fruit yield and chemical composition of two landraces of Trichosanthes cucumerina L. For the purpose of the study, two landraces of T. cucumerina named Landrace I and Landrace II were used. The five levels of phosphorus evaluated were 0, 30, 60, 90 and 120 kg P2O5 ha−1 using single super phosphate fertilizer (8% P). Statistical analysis showed that 90 kg P2O5 ha−1 gave statistically significant higher fruit yield (16.4 tons ha−1) compared to other P levels. The fruit yield of the two Landraces did not differ significantly. Except for crude protein content, the 90 kg P2O5 ha−1 produced significantly higher ether extract (1.22 g 100 g−1), crude fibre (1.93 g 100 g−1), moisture content (90.5 g 100 g−1), ash (0.90 g 100 g−1), total sugars (0.81 g 100 g−1) and ascorbic acid (28.7 mg 100 g−1) than other P levels. The essential amino acids compositions were also significantly higher at 90 g 100 g−1 compared to other lower P levels. Landrace I had significantly higher ether extract (0.90 g 100 g−1) content than Landrace II (0.62 g 100 g−1) while Landrace II in turn had significantly higher total sugar (0.76 g 100 g−1) compared to Landrace I (0.61 g 100 g−1). The essential amino acids composition is high and the oxalate composition is low. The high ascorbic acid and amino acid content together with a low oxalate composition suggested a strong basis for encouraging the cultivation of this indigenous fruit vegetable to augment nutrient requirement, improve diet and consequently alleviate poverty, preserve the biodiversity and increase the gene bank of neglected wild species of high quality nutrient sources.  相似文献   

16.
Isoflavones have been associated with several health protective effects. In this work spontaneous legume plants were screened as putative sources of dietary isoflavones. A molecular identification of the collected species was performed throughout DNA barcoding using ITS, rbcL, rpoC1 and matK sequences. The use of a multi-locus barcoding system complemented with basic morphological information allowed the unequivocal identification at the species level of 90% of the samples. The determination of isoflavone content was performed by high-performance liquid chromatography with diode-array detection. Total average contents in the studied species were significantly different, Ononis natrix and Cytisus scoparius possessing the highest total isoflavones content (396 and 273 mg kg−1, respectively) and Lotus creticus, the lowest (20 mg kg−1). The correlation of total isoflavone content with the phylogeny of this set of plants as determined by the rpoC1 sequences was evaluated for the first time.  相似文献   

17.
Detrital and living leaves of the tropical seagrass Syringodium filiforme Kütz. were screened for their phenolic contents. For the first time, the major polyphenols were identified, as chicoric acid (CA) and caftaric acid (CAF), by means of NMR and LC/MS. They were quantified in methanolic and aqueous crude extracts using HPLC. Highest amounts were obtained for extracts sequentially prepared under reflux of methanol, then aqueous-methanol. The concentrations found, respectively, ranged from 0.51 to 1.68 mg (g dw−1) for CAF and 0.94–5.26 mg (g dw−1) for CA (of plant dry mass g dw)−1. This is the first report of CAF in a seagrass and CA in S. filiforme. Considering the demonstrated therapeutic applications of CA, its high value-added on the nutraceutical market, and its rare occurrence in the plant kingdom, the significant content found in S. filiforme leaves makes this abundant renewable raw material of interest for the pharmaceutical and food industries.  相似文献   

18.
The effect on quality were assessed for gilthead seabream fed five different diets: control (basal diet); BHT (basal diet with 200 mg kg−1 of butylated hydroxytoluene); rosemary (basal diet with 600 mg kg−1 of rosemary extract - Rosmarinus officinalis); carvacrol (basal diet with 500 mg kg−1 of essential oil of Thymbra capitata, carvacrol chemotype); and thymol (basal diet with 500 mg g−1 of essential oil of Thymus zygis, subspecies gracilis, thymol chemotype). After 18 weeks of experimentation, the animals were stored on ice at 4 °C for 0, 7, 14, and 21 days. Physical-chemical, microbiological and sensory analyses were carried out at each sampling point to determine the degree of deterioration in the gilthead seabream. Lower indices of oxidation were observed in animals who were administered feeds supplemented with BHT, carvacrol and (to a lesser degree) rosemary. Lower bacteria counts were observed for the BHT and thymol groups, in addition to a slower deterioration in terms of sensory perception. Accordingly, the addition of natural antioxidants to the diet may have an added effect on fish quality, delaying post mortem deterioration.  相似文献   

19.
Samples of cultivated Ulva clathrata were collected from a medium scale system (MSS, 1.5 × 1.5 m tank), or from a large scale system (LSS, 0.8 ha earthen pond). MSS samples were dried directly while the LSS sample was washed in freshwater and pressed before drying. Crude protein content ranged 20–26%, essential amino acids accounting for 32–36% of crude protein. The main analysed monosaccharides were rhamnose (36–40%), uronic acids (27–29%), xylose (10–13%) and glucose (10–16%). Some notable variations between MSS and LSS samples were observed for total dietary fibre (26% vs 41%), saturated fatty acids (31% vs 51%), PUFAS (33% vs 13%), carotenoids (358 vs 169 mg kg−1 dw) and for Ca (9 vs 19 g kg−1), Fe (0.6 vs 4.2 g kg−1), Cu (44 vs 14 mg kg−1), Zn (93 vs 17 mg kg−1) and As (2 vs 9 mg kg−1). The chemical composition of U. clathrata indicates that it has a good potential for its use in human and animal food.  相似文献   

20.
Dichloromethane, ethyl acetate, acetone, methanol, and water extracts prepared from the fruits and leaves of Laurocerasus officinalis Roem. (LO) (Rosaceae) were screened for their cholinesterase inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), the key enzymes in pathogenesis of Alzheimer's disease (AD), using ELISA microplate reader at 50, 100, and 200 ??g mL−1. As AD is associated with oxidative stress, the antioxidant activity of the extracts was also tested by radical-forming methods against 2,2-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylendiamine (DMPD), and superoxide radicals as well as iron-related methods; iron-chelating capacity and ferric-reducing antioxidant power (FRAP) assays. Total phenol and flavonoid quantification was achieved using Folin-Ciocalteau and AlCl3 reagents, respectively. The highest AChE (44.01 ± 1.75%) and BChE (19.91 ± 0.37%) inhibition was caused by the LO-leaf-methanol extract 200 ??g mL−1, while it showed the best radical-scavenging activity against DPPH at 2000 ??g mL−1. Only, the dichloromethane and water extracts of the fruits and the leaf water extract had an iron-chelating capacity, while the leaf methanol extract displayed the highest FRAP. The leaf methanol extract (113.45 ± 0.71 mg g−1 extract) was found to be the richest in total phenols, while the leaf acetone extract (139.90 ± 4.64 mg g−1 extract) had the most abundant amount of total flavonoids.  相似文献   

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