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1.
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   

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.
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   

4.
Flavonoids contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities and the ferric-reducing antioxidant power (FRAP) were compared in three black soybean varieties CRWD, Tainan 3 and Tainan 5. Varietal differences in antioxidant contents existed among the tested varieties. Variety CRWD accumulated more total phenolics (7.49 mg g−1) and isoflavones (1.77 mg g−1) than varieties Tainan 3 (7.05 mg g−1 total phenolics and 1.58 mg g−1 isoflavones) and Tainan 5 (4.38 mg g−1 total phenolics and 0.63 mg g−1 isoflavones). CRWD also accumulated more proanthocyanidins in seed coat than Tainan 3 and Tainan 5. CRWD also demonstrated greater DPPH and FRAP activities than the other two cultivars. Stepwise regressions indicated that both DPPH and FRAP activities were correlated well with the total contents of phenolics and flavonoids, with total phenolics being the most important anti-oxidative factor. The present results indicate that CRWD has greater anti-oxidative responses than Tainan 3 or Tainan 5, and is useful in functional food and other applications.  相似文献   

5.
Tropical highland blackberry (Rubus adenotrichus Schltdl.) is a good source of antioxidants and contains appreciable levels of phenolic compounds, mainly ellagitannins and anthocyanins. This study examined the influence of three ripening stages on phenolic contents. Major anthocyanin pigments increased from 0.20 (red fruit) to 1.34 mg g−1 fresh weight (FW) (fully ripe fruit), whereas ellagitannins and ellagic acid derivatives dropped from 3.8 to 2.2 mg ellagic acid equivalents g−1 (FW). Flavonols also dropped from 5.1 to 2.0 mg quercetin equivalents 100 g−1 (FW). Consequently, values for total phenolic compounds ranged from 5.8 to 5.2 mg gallic acid equivalents g−1 (FW), showing no specific trend. Antioxidant activity (H-ORAC) increased from 38.29 to 64.00 μmol of Trolox equivalents g−1 (FW) during ripening. When compared with other commercial cultivars, R. adenotrichus stands out for high H-ORAC value, although comparatively it possesses low anthocyanin content and average total phenolic content.  相似文献   

6.
Maximal water uptake and diffusivity were determined from experimental soaking curves using analytical solution of the second Fick’s law in four barley samples displaying distinct hydrolytic activities during malting. Water diffusivities in the whole grains, were found to vary between 5.28 and 7.61 × 10−12 m2/s, whereas those of the endosperms were 5-7-fold higher, ranging between 35.2 and 49.5 × 10−12 m2/s. These differences highlighted the potential barrier role of the grain outer layers. The relationships between maximal water uptake, water diffusivity and grain biochemical and structural parameters (i.e. hardness and other less studied parameters such as vitreousness and porosity) was investigated. The lowest water diffusivity value was obtained for the barley sample displaying the lowest porosity, highest hardness and vitreousness but the highest enzymatic activity during malting, in contradiction with what is generally stated. Water diffusion was not found as the limiting factor for malt quality and, thus, its role during barley steeping has to be reconsidered.  相似文献   

7.
The effect of solar radiation on the quercetin and kaempferol contents in the inflorescence of three broccoli cultivars (‘Lord’, ‘Marathon’ and ‘Fiesta’) was investigated from 1999 to 2001. Great differences in the contents of both flavonols, dependent on growing time and cultivar, were found. Quercetin and kaempferol contents varied from 14.3 to 81.0 mg kg−1 f.w. and from 35.9 to 213 mg kg−1 f.w., respectively. Inflorescences of the cultivar ‘Lord’ were characterised by the highest mean content of quercetin and those of cultivar ‘Fiesta’ of kaempferol. The contents of both flavonols were highly positively correlated with total solar radiation in the period from planting to the harvest of broccoli inflorescences.  相似文献   

8.
The physical characteristics (diameters, height and mass), chemical composition (tritratable acidity, soluble solids, pH, moisture, ash, protein, lipids and total dietary fiber), occurrence and content of vitamin C (ascorbic acid and dehydroascorbic acid), carotenoids (??-carotene, ??-carotene, ??-cryptoxanthin and lycopene), vitamin E (??-, ??-, ??- and ??-tocopherol and tocotrienol) and folates (tetrahydrofolate, 5-methyltetrahydrofolate and 5-formyltetrahydrofolate) were evaluated in the cagaita obtained from the Cerrado of Minas Gerais, Brazil. The analyses of vitamin C and carotenoids were performed by HPLC-DAD and vitamin E and folates by HPLC with fluorescence detection. The cagaita pulp presented high content of moisture (91.56 g 100 g− 1), vitamin C (34.11 mg 100 g− 1) and folates (25.74 ??g 100 g− 1). The presence of protein (0.63 g 100 g− 1), ash (0.18 g 100 g− 1), lipids (0.57 g 100 g− 1), carbohydrates (5.54 g 100 g− 1), dietary fiber (1.54 g 100 g− 1) and carotenoids (0.77 mg 100 g− 1) was observed in its composition. Vitamin E isomers were not detected. Consumption of cagaita (100 g) contributed significantly to supply the daily requirements of vitamin C (on average 71.0%), vitamin A (on average 7.5%) and folates (on average 7.9%). The cagaita showed high pulp yield, reduced total energy value and was considered a source of vitamin C, which play important role in human health.  相似文献   

9.
The cholesterol content of eggs produced by the Slovenian autochthonous Styrian hen in comparison with eggs of the Isa Brown, reared in two different rearing systems, was determined. Eggs were collected four times during the year. The cholesterol content was determined by the enzymatic-spectrophotometric method. The influence of genotype, in two different rearing systems, on the cholesterol content in eggs was studied. The cholesterol content determined in eggs from cages was 13.1 ± 0.43 mg g−1 yolk of the Styrian hens as compared to 11.4 ± 0.49 mg g−1 yolk of Isa Brown hens. The cholesterol content determined in free range eggs was 13.6 ± 0.22 mg g−1 yolk of the Styrian hen and 11.8 ± 0.30 mg g−1 yolk of Isa Brown.  相似文献   

10.
T. Polak  B. ?lender 《LWT》2009,42(1):256-2016
The mutagenic heterocyclic amines (HAs) originate in processed proteinaceous food. The effects of ageing (non-aged - i.e. 24 h post mortem vs. 14 and 28 days post mortem kept at 1 °C) and final internal temperature on cooking (Ti, 65 and 80 °C) on the content of HAs in grilled steaks (two-plated grill, temperature of 220 °C) were studied. HA precursors (creatine, creatinine, and free amino acids) and ageing indicators, such as instrumentally measured colour values, pHultimate values and length of myofibrilar fragments on raw and cutting values on grilled beef Longissimus dorsi muscles were determined. The muscles originated from eight commercially slaughtered Simmental bulls, 19-20 months old. The content of HAs was determined by a solid-phase extraction procedure. Meat ageing is accompanied by large changes in the chemical composition and structure of muscle tissues. In general, all the ageing indicators and precursors of HAs were influenced by ageing time at the 5% level or less. Creatine content declined significantly (non-aged: 6.00 mg g−1, 14 days: 5.82 mg g−1, and 28 days: 5.55 mg g−1) and creatinine increased with days of ageing (non-aged: 0.19 mg g−1, 14 days: 0.24 mg g−1, and 28 days: 0.26 mg g−1). Higher contents of total free amino acids were determined after 14 and 28 days of storage (28.18 μmol g−1 and 37.59 μmol g−1) than in non-aged beef (19.00 μmol g−1). In this study, two HAs were determined: MeIQx (2-amino-3,8-dimethyl-imidazo[4,5-f]quinoxaline) and PhIP (2—amino-1-methyl-6-phenylimidazo-[4,5-b]pyridine). The content of HAs increases with ageing. At lower Ti, more MeIQx was formed; at higher Ti, more PhIP was formed. MeIQx was present in all samples while PhIP was found only in samples grilled to higher Ti. Samples treated to Ti = 80 °C generally contained less HAs (non-aged meat: 0.20 ng g−1, 14 days: 0.26 ng g−1, and 28 days: 0.28 ng g−1) than samples treated to Ti = 65 °C (non-aged meat: 0.19 ng g−1, 14 days: 0.36 ng g−1, and 28 days: 0.39 ng g−1) on account of MeIQx thermolability.  相似文献   

11.
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   

12.
Ethyl formate was readily determined with a gas chromatograph (GC) equipped with a flame ionisation detector. Natural levels of ethyl formate in Australian wheat, barley, oats, and canola were analysed by GC, after extraction with ammonium nitrate solution. Background levels of ethyl formate were present in newly harvested and stored grain. The levels of ethyl formate (0.1-0.6 mg kg−1) in grains varied with commodity, temperature, moisture and period of storage. The values ranged from 0.1 to 0.2 mg kg−1 for newly harvested wheat, barley and oats, and 0.3-0.4 mg kg−1 for newly harvested canola. Ethyl formate was present in grains at harvest, increased during the first 7 months of storage, and then began to decline, particularly at grain temperatures higher than 25°C and moisture contents higher than 12.5% (for wheat, barley and oats) and 6.5% (for canola). The natural levels of ethyl formate should be considered when establishing maximum residue limits.  相似文献   

13.
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   

14.
Chemical composition of eight sweet chestnut cultivars from the three protected designation of origin (PDO) areas in the Trás-os-Montes region were studied: Aveleira, Rebordã, Trigueira and Zeive from PDO ‘Terra Fria’, Demanda, Longal and Martaínha from PDO ‘Soutos da Lapa’ and Judia from PDO ‘Padrela’. Chestnuts were characterised by high moisture content (∼50%), high levels of starch (43 g 100 g−1 dry matter – d.m.) and low fat content (3 g 100 g−1 d.m.). Nuts contained significant amounts of fibre (3% d.m.), were rich in K (∼750 mg 100 g−1 d.m.), P (∼120 mg 100 g−1 d.m.) and Mg (∼75 mg 100 g−1 d.m.). Moreover, chestnuts are a good source of total amino acids (6–9 g 100 g−1 d.m.). Amino acid profiles were dominated by l-aspartic acid, followed by l-glutamic acid, leucine, l-alanine and arginine. These results provide additional information about the nutritional value of each cultivar and confirm that chestnuts are an interesting healthy food.  相似文献   

15.
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   

16.
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   

17.
To explore wild genetic resources for improving fruit and processing quality of cultivated grape cultivars, the polyphenolic composition and content in the ripe berries of 147 grape accessions from 16 Vitis species for two consecutive years were characterised. A total of 48 polyphenolic compounds, including 28 anthocyanins, 6 flavonols, 6 flavanols, 6 hydroxycinnamic derivatives, and 2 hydroxybenzoic acids, were identified via HPLC-MS and quantified by HPLC-DAD. These wild grape species had unique presence of abundant di-glucoside derivatives of anthocyanins. In addition, anthocyanins in most wild species were predominantly nonacylated. The mean contents for anthocyanins, flavanols, flavonols, hydroxycinnamic derivatives, and hydroxybenzoic acids were 9.610, 0.769, 0.093, 0.441 and 0.027 mg g−1 FW, respectively. They were about 2 to 10 folds higher than their respective counterparts in the most widely cultivated grape species Vitis vinifera. As expected, most of these groups of compounds were correlated negatively with berry weight, but positively with the content of total soluble solids.  相似文献   

18.
Here we report on accumulation patterns of anthocyanins and of β-carotene during fruit maturation, between 82 and 125 days after flowering, of two apricot (Prunus armeniaca L.) cultivars, A3576 and A3751. Both cultivars displayed an intense red colour of the skin but differed in their genetic background. The pigments were extracted from skin and flesh, separately, and analysed using HPLC-DAD-MS. Out of three anthocyanins detected here, the major compound, cyanidin-3-O-rutinoside was present at 75%. The two minor compounds were cyanidin-3-O-glucoside and peonidin-3-O-rutinoside. This is the first time that peonidin-3-O-rutinoside has been detected in apricot fruit. During maturation, A3751 accumulated anthocyanins in both skin and flesh, whereas anthocyanins were present only in the skin of A3576. The skin anthocyanin content was higher in A3751 (296 mg kg−1) than in A3576 (41 mg kg−1). Maximum anthocyanin levels were attained after 108 and 118 days of flowering in A3751 and A3576, respectively, in conjunction with loss of firmness and red colour acquisition on the un-blushed side of the fruit. At the end of ripening, the β-carotene flesh concentration reached 5 mg kg−1 in A3576 and 15 mg kg−1 in A3751. A significant effect of environment was observed on the anthocyanin content in the two cultivars.  相似文献   

19.
Detritus of Zostera noltii and Zostera marina collected from the beaches of Arcachon lagoon (France) over a 30-month period were screened as a new source of rosmarinic acid (RA), a phenolic acid and an economically important metabolite. The seasonal variation of the RA content was quantified in methanolic crude extracts using high-performance liquid chromatography. Concentrations of RA ranged from 2.2 to 18.0 mg g−1 (dw) for Z. noltii and 1.3 to 11.2 mg g−1 (dw) for Z. marina. This is the first time RA has been isolated from Z. noltii; detrital leaves of Zostera have never before been screened for their bioactive substances. The high RA content of Zostera flotsam is of interest for both the cosmetic and herbal industries. These results show that there is a real potential for harvesting beachcast Zostera.  相似文献   

20.
Four different phytopharmaceutical dosage forms for use in weight control programs were analyzed. Two different ground herbal blends and their correspondent infusions, a capsule and a tincture were investigated for the presence of compounds used as adulterants in these products. A capillary electrophoresis (CE) method was developed and validated. The optimized experimental conditions were: BGE, sodium tetraborate buffer 20 mM, pH 9.2, voltage applied 30 kV, capillary temperature 25 °C, injection sample at 0.5 Psi during 5 s. Ephedrine, norephedrine, caffeine and furosemide were baseline separated in less than 7 min; the migration times were found to be 2.65, 2.90, 3.75 and 6.58 min, respectively. The analysis showed in sample 3 concentrations of 0.45 ± 0.03 mg g−1 (ephedrine), 0.33 ± 0.02 mg g−1 (norephedrine), 1.09 ± 0.41 mg g−1 (caffeine) and 0.80 ± 0.17 mg g−1 (furosemide). Caffeine content in samples 1, 2 and 4 was 0.61 ± 0.06 mg g−1, 15.66 ± 1.05 mg g−1 and 2.27 ± 0.13 mg ml−1, respectively. Linearity was obtained in the concentration range of 1–1000 μg ml−1. Limits of detection (LOD) and quantification (LOQ) were determined as 0.42 μg ml−1 and 1.40 μg ml−1 (ephedrine), 0.47 μg ml−1 and 1.40 μg ml−1 (norephedrine), 0.12 μg ml−1 and 0.48 μg ml−1 (caffeine), 0.22 μg ml−1 and 0.73 μg ml−1 (furosemide).  相似文献   

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