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1.
In this study, oils, micronutrients and heavy metal contents of tomato seeds and tomato (Lycopersicon esculentum) fruits from different Turkish resources were determined. The tomato seed oil contains more than 84% unsaturated fatty acids, such as oleic acid, linoleic acid and linolenic acid. The fatty acid composition of tomato seed oil was similar to that of soybean oil. Under supercritical conditions, partial thermal degradation occurs on the double bonds of unsaturated aliphatic carbons chains in fatty acids. Linoleic acid was the major unsaturated fatty acid in tomato seed oil. The concentrations of metals (Pb, Cd, Fe, Cu, Zn, Na, K, Ca and Mg) were determined in tomato samples.  相似文献   

2.
The antioxidant effectiveness of different hydroxycinnamic acids for inhibiting the formation of off-flavours associated to rancidity in minced frozen horse mackerel white muscle stored at −10 and −18 °C was studied. The influence of lipid oxidation on protein aggregation, protein denaturation and water holding capacity was also determined. Caffeic acid, o-coumaric acid and ferulic acid were the antioxidants tested. The order of antioxidant effectiveness was caffeic acid > ferulic acid > o-coumaric acid accordingly with previous results obtained in chilled horse mackerel. A strong dependence of antioxidant effectiveness to the ratio lipid/antioxidant concentration was observed. There was no evidence to suggest that antioxidants reduce protein aggregation or water holding capacity changes. Protein aggregation was not accompanied by gross protein denaturation, as monitored by differential scanning calorimetry. No evidence was found for a link between extent of lipid oxidation and degree of protein aggregation or water holding capacity changes.  相似文献   

3.
The phenolic profiles of Polish honey samples from heather (Calluna vulgaris L.) and buckwheat (Fagopyrum esculentum L.) were determined. The phenolic components were isolated from honey samples using Amberlite-XAD-2 as a solid-phase extraction sorbent. For the determination of the composition of the honey extracts HPLC with photodiode array detector was applied. Identification and quantification of phenolics was performed by comparison of their retention times and UV spectra with those of standard solutions of pure reference substances and by using those references as external standards. From among 20 commercially available standards over 15 of them were identified as present in all analysed samples. Taking into account the samples of the same unifloral honeys, similar qualitative but slightly quantitatively different phenolic characteristic profiles were observed. These profiles might be considered as “fingerprints” of heather and buckwheat honeys.  相似文献   

4.
Coriandrum sativum L. is a source of a variety of polyphenols and other phytochemicals, related to its high antioxidant activity and to its use for indigestion, rheumatism, and prevention of lipid peroxidation damage. Plant cell cultures are a means to study or to produce some active metabolites, such as polyphenols. This technique was applied to the investigation of coriander, and a detailed analysis of individual polyphenols in vivo and in vitro grown samples was performed. The in vivo vegetative parts showed quercetin derivatives as the main flavonoids and quercetin-3-O-rutinoside (3296 mg/kg dw) was the main polyphenol found in this part of coriander. The fruits revealed only phenolic acids and derivatives, caffeoyl N-tryptophan hexoside (45.33 mg/kg dw) being the most abundant phenolic derivative. In vitro samples also gave a high diversity of polyphenols, being C-glycosylated apigenin (2983 mg/kg dw) the main compound. Anthocyanins were only found in clone A, which was certainly related to its purple pigmentation, and peonidin-3-O-feruloylglucoside-5-O-glucoside was the major anthocyanin found (1.70 μg/kg dw). In vitro culture can be used to explore new industrial, pharmaceutical, and medicinal potentialities, such as the production of secondary metabolites like flavonoids.  相似文献   

5.
Melissa officinalis L. (lemon balm) is normally consumed as an infusion and presents therapeutic properties, such as sedative, carminative and antispasmodic, also being included in some pharmaceutical preparations. The phenolic profiles of different samples of lemon balm, prepared as infusions, were evaluated by HPLC-DAD-ESI/MS. The profiles were compared in order to understand the differences between cultivated, in vitro cultured and commercial (bags and granulated) samples. All the samples showed a similar phenolic profile, presenting differences only in the quantities found of each compound. Rosmarinic acid was the most abundant compound, being higher in commercial samples, especially in tea bag sample (55.68 mg/g of infusion) and lower in in vitro cultured sample (15.46 mg/g). Moreover, dimers, trimers and tetramers of caffeic acid were identified and quantified for the first time in lemon balm. Only one flavonoid, luteolin-3′-O-glucuronide was found in all the samples, ranging from 8.43 mg/g in commercial granulate sample to 1.22 mg/g in in vitro cultured sample. Overall, cultivated and in vitro cultured samples presented the lowest amounts of phenolic compounds (59.59 and 30.21 mg/g, respectively); otherwise, commercial samples showed the highest contents (109.24 mg/g for tea bag and 101.03 mg/g for granulate sample). The present study shows that infusion of lemon balm can be a source of phenolic compounds, known for their bioactive effects.  相似文献   

6.
Camel milk, similar to cow milk, contains all of the essential nutrients as well as potentially health-beneficial compounds with anticarcinogenic, antihypertensive, and antioxidant properties. Camel milk has been used for the treatment of allergies to cow milk, diabetes, and autism. Camel milk helps decrease cholesterol levels in blood and improves metabolism. One of the most desirable food tastes is sweetness. However, the excessive ingestion of sugar negatively affects human health. Monk fruit sweetener is a natural, 0-calorie sweetener with many health-beneficial functions. Monk fruit sweetener helps decrease symptoms of asthma and diabetes, prevents oxidation and cancer, protects the liver, regulates immune function, and lowers glucose levels. Monk fruit sweetener is 100 to 250 times sweeter than sucrose. The objective of this study was to examine the influence of different concentrations of monk fruit sweetener on the physicochemical properties and microbiological counts of drinking yogurt made from camel milk. Camel milk drinking yogurt was produced with 0, 0.42, 1.27, and 2.54 g/L of monk fruit sweetener and stored for 42 d. The physicochemical characteristics and microbiological counts of yogurts were measured at d 1, 7, 14, 21, 28, 35, and 42. For the physicochemical characteristics, pH, titratable acidity, viscosity, and color [lightness-darkness (L*), red-green axis (a*), yellow-blue axis (b*), chroma (C*), and hue angle (h*)] values were evaluated. The counts of Streptococcus thermophilus, Lactobacillus bulgaricus, Lactobacillus acidophilus, coliforms, and yeast and mold were determined. Three replications were conducted. The sweetener addition significantly influenced pH, viscosity, and color (a*, b*, C*, and h*) values. Control samples had significantly higher pH values, lower viscosity, lower b* and C* values, and higher h* values than the samples with 1.27 and 2.54 g/L of monk fruit sweetener. Growth of S. thermophilus, L. bulgaricus, and probiotic culture L. acidophilus was not affected by the incorporation of monk fruit sweetener. Monk fruit sweetener can be added in camel milk yogurts as a health-beneficial 0-calorie sweetener.  相似文献   

7.
This paper presents a new approach for estimating antioxidant activity and anthocyanin content at ripening stages of sweet cherry by combining image processing and artificial neural network (ANN) techniques. The system was consisted of a CCD camera, fluorescent lights, capture card and MATLAB software. Anthocyanin content and antioxidant activity were determined by pH differential and 2, 2‐diphenyl‐1‐picrylhydrazyl methods, respectively. It was found that anthocyanin content was constantly increased during ripening stages, and antioxidant activity decreased during the early stages of development but increased from stage five. Several ANN models were designed and tested. Among these networks, a two hidden layer network with 11‐6‐20‐1 architecture had the highest correlation coefficient (R = 0.965) and the lowest value of mean square error (MSE) (215.4) for modelling anthocyanin content. Similarly, a two hidden layer network with 11‐14‐9‐1 architecture had the highest correlation coefficient (R = 0.914) and the lowest value of MSE (0.070) for modelling antioxidant activity.  相似文献   

8.
9.
The effect of high pressure homogenisation (HPH) on structure (Bostwick consistency, particle size distribution and microstructure) and carotenoid in vitro bioaccessibility of different tomato pulps was investigated. HPH decreased tomato particle size due to matrix disruption and increased product consistency, probably due to the formation of a fibre network. Homogenisation also resulted in a decrease of in vitro bioaccessibility of lycopene, ζ-carotene, and lutein. Such decrease was attributed to the structuring effect of HPH. An inverse relation between tomato consistency and carotenoid in vitro bioaccessibility was found. This dependency was affected by carotenoid species and its localisation within the matrix. It could be observed that one matrix (e.g. (homogenised) red tomato pulp) can contain carotenoids with a very low bioaccessibility (lycopene) as well as carotenoids with a very high bioaccessibility (lutein), indicating that carotenoid bioaccessibility is not solely dependent on the matrix.  相似文献   

10.
In pot and field experiments cereals were grown with greatly differing rates of N, P and K applications. For maize and sorghum, soil moisture levels were also varied. N applications, P- and K-deficiency, and moisture stress generally increased the total N content of grain, from 1.06 to 2.68, 1.01 to 2.42 and 0.81 to 2.33% (as % of DM) for maize, sorghum and rice, respectively. P, K and moisture stress affected the amino acid composition only indirectly through their effects on N concentration. In all three cereals increasing N concentrations were associated with decreases in crude protein of lysine, methionine, cystine, threonine, tryptophan and, generally, with increases of isoleucine, leucine, phenylalanine and glutamate. Lysine as a percentage of dry matter increased up to the highest N concentration in all three cereals. Linear regressions with significant correlation coefficients were found between concentrations of most (g 16 g?1 N) or all (mg 100 g?1 DM) amino acids and N content of grain. Based on all experimental data equations for lysine were: g 16 g?1 N=4.44–0.89 × %N; 4.23–0.86 × % N; 4.39–0.42 × % N for maize, sorghum and rice, respectively. Correction of P- and K-deficiency decreased N content of grain and resulted in higher lysine content and better nutritional value of grain protein, whereas correction of N-deficiency had the opposite effect. The amino acid composition of rice was much more balanced than that of maize and sorghum with a leucine/isoleucine ratio of 2 compared to that of 3 in maize and sorghum. In rat feeding experiments true digestibility of maize and sorghum protein was high (about 95%) but increased only slightly with increasing N in grain, whereas the biological value decreased considerably, from 63 to 55 and from 70 to 58, respectively. The chemical score underestimated the nutritional value of both cereal proteins.  相似文献   

11.
This study evaluated the influence of NPK fertilizer on protein, fibre, ash, fat, carbohydrate, antioxidant activities and antioxidant phenolic compounds in immature and mature fruits of pumpkin. The treatment consisted of six NPK levels (0, 50, 100, 150, 200 and 250 kg/ha), and was replicated six times in a randomized complete block design (RCBD). Proximate analysis and antioxidant assays were done using standard analytical methods. At control and lower NPK rates, the proximate compositions and antioxidant profile of pumpkin fruits decreased with increasing NPK fertilizer. Between the control and the highest fertilizer rate, proximate compositions decreased by 7-62% while the antioxidant profile decreased by 13-79% for both immature and mature fruits. Across all the measured parameters, mature fruit had higher proximate contents and higher antioxidant concentrations. For the high health value of pumpkin fruits to be maintained, little or no NPK fertilizer should be applied.  相似文献   

12.
The effects of age, gender and production region on the fatty acid composition of springbok Musculus longissimus dorsi (LD) were investigated. The major fatty acid of the LD muscle was stearic acid (C18:0), which contributed 23.92–27.02%. Oleic acid (C18:1) represented the largest component (16.33–20.45%) of the mono-unsaturated fatty acids (MUFA). The major n − 6 polyunsaturated fatty acid (PUFA) was C18:2n − 6, which formed 18.77–21.62%, whereas C18:3n − 3 (3.33–4.00%) was the most abundant n − 3 PUFA. The n − 6:n − 3 ratio of the meat varied from 3.02 to 3.35, with an average ratio of 3.2. Polyunsaturated to saturated (P:S) ratios varied between 0.96 and 1.18 and averaged at 1.06. Total MUFA was found to be higher (P < 0.05) in males (20.99%) than females (16.67%). The cholesterol content of the meat varied from 54.45 to 59.34 mg/100 g muscle. Linear correlations between the fatty acid and the intramuscular fat (IMF) content indicated a significant increase in certain saturated and mono-unsaturated fatty acids with increasing IMF content of the meat.  相似文献   

13.
Peach fruit (Prunuspersica L. cv. Beijing 33) did not show symptoms of chilling injury in 0 °C-Air or 0 °C-CA, but did in 5 °C-Air after 21 d. The mechanisms by which 0 °C storage could activate chilling tolerance of peach fruit were investigated by analysing characteristics of plasma membrane. We found that peach fruit stored in 0 °C-Air and 0 °C-CA had much higher linolenic acid content and unsaturation degree of plasma membrane than did that in 5 °C-Air. In addition, the fruits stored in 0 °C-CA showed a higher membrane fluidity and membrane integrity than did that in 0 °C-Air, which was related to the accumulation of N-acylphosphatidylethanolamine (NAPE) of peach fruits stored in 0 °C-CA. Based on these results, it appears that a higher unsaturation degree of membrane lipid and NAPE accumulation are beneficial for maintaining membrane fluidity, leading to an enhanced tolerance of peach fruit to chilling stress.  相似文献   

14.
The effects of age, gender and production region on the chemical, mineral and amino acid composition of the M. longissimus dorsi (LD) muscle of springbok were investigated. There was a significant gender*region interaction for protein content – for the four production regions it varied between 18.80 and 21.16 g/100 g. The intramuscular fat (IMF) content of the LD muscle varied between 1.32 and 3.46 g/100 g. Females (3.13 ± 0.28 g/100 g) had a higher (P < 0.05) fat content than males (1.35 ± 0.08 g/100 g). The IMF content of the adult (2.45 ± 0.26 g/100 g) and sub-adult (2.50 ± 0.28 g/100 g) categories was higher (P < 0.05) in comparison to that of the lambs (1.32 ± 0.11 g/100 g). An inverse correlation was noted between the IMF and moisture content (r = −0.49, P < 0.001) of the meat. The two main amino acids were glutamic and aspartic acid, which contributed 2.47–2.74 and 2.31–2.54 g/100 g of dry matter, respectively. Phosphorous was the predominant mineral in the LD muscle (122.92–159.78 mg/100 g of dry matter), followed by potassium (119.44–131.25 mg/100 g of dry matter) and calcium (6.57–145.18 mg/100 g of dry matter). Production region had a significant effect on the mineral and amino acid composition of the meat, while the effects of age and gender were found to be insignificant.  相似文献   

15.
Springbok is the most extensively cropped game species in South Africa. The effects of age (adult, sub-adult, lamb), gender and production region on the physical attributes (pH24, cooking and drip loss, Warner Bratzler shear force and colour) were determined using samples of the M. longissimus dorsi (LD) muscles of 166 springbok. Stressed animals had a higher (P < 0.05) pH24 (6.3 ± 0.07), as observed in the meat originating from the Caledon region. This meat had lower (P < 0.05) cooking loss (27.2 ± 0.62%) and drip loss (1.8 ± 0.08%) values in comparison to meat originating from the other regions. Inverse correlations were noted between pH24 and drip loss (r = −0.26, P < 0.01) and cooking loss (r = −0.42, P < 0.001). Shear force values (kg/1.27 cm diameter) correlated positively (r = 0.25, P < 0.01) with pH24. Age-related effects on tenderness were small in comparison with pH24 effects. CIELab colorimetric values were typical of game meat and venison (L* < 40, high a* and low b* values). It was noted that pH24 correlated negatively (r = −0.51, P < 0.001) and positively (r = 0.33, P < 0.001) with the hue-angle and the chroma value of colour, respectively. Springbok originating from Caledon had a significantly (P < 0.05) higher a* value, indicating meat to be more red with higher colour saturation.  相似文献   

16.
A large number of studies recognize glucocorticoids (Gc) as suppressors of inflammation; Gc exert an important role in coordinating the magnitude and duration of host immune responses. In the present in vitro investigation, we tested incremental levels of cortisol to verify the immunosuppressive or immunopermissive role of cortisol in sheep peripheral blood mononuclear cells (PBMC) after acute and chronic stress. Phytohemagglutinin (PHA)-stimulated PBMC were cultured for 24 h and 96 h at 37°C with 5% of CO2 and varying cortisol levels: 10 ng/mL (baseline), 100 ng/mL (physiological poststressor), and 1,000 ng/mL [hyperactivated hypothalamic-pituitary-adrenal (HPA) axis]. The cell-free supernatants were collected for determination of IL-6, IL-1β, and IL-10 by ELISA, and the bromodeoxyuridine assay was performed on cells. Physiological cortisol concentration negatively affected the levels of IL-6 secreted by PBMC, resulting in increased cell proliferation after acute stress (24 h of incubation). However, physiological cortisol concentration exhibited a reduction in cell proliferation induced by increased levels of IL-6 secreted by PBMC during chronic stress (96 h of incubation). The cortisol concentration representing a hyperactivated HPA axis led to a reduction in cell proliferation after acute stress, which was probably induced by the elevated IL-10 production. Our results demonstrate that in sheep the effect of Gc on the immune system was related to the magnitude and the duration of stress. In particular, cortisol levels higher than physiological concentrations suppressed cell proliferation soon after acute stress. Instead, the physiological poststressor concentration of cortisol affected the immune responses in a bidirectional manner depending on the duration of the stressor.  相似文献   

17.
The evolution of fatty acid (FA) and terpenoid profiles was studied in milk (n = 20) and “Bitto” (n = 3), a protected designation of origin cheese produced in a restricted Italian alpine area. Milk came from 25 Italian Brown cows successively grazing pastures at 1400, 2100 and 2200 m during transhumance in June–September 2006. The fat matter was analyzed for FAs and terpenes by means of gas chromatography and purge & trap/gas chromatography–mass spectrometry, respectively. FA composition of milk fat varied significantly (p < 0.0001) in relation to contents of conjugated linoleic acid (CLA), stearic, linoleic and trans-vaccenic acids. Similar monoterpene profiles characterized milk fat from cows grazing the different pastures and the highest amount of terpenes was measured in milk coming from cows grazing at 1400 m. High levels of δ3-carene in milk fat were likely related to the important presence of Ligusticum mutellina in the pasture. Only negligible amounts of sesquiterpenes were detected in milk fat whereas they were the most abundant class in fodder. Both FA and terpene profiles of ripened (70 days) cheeses resembled those of the original milks. Overall, results confirm the influence of the botanical composition of mountain pastures both in enhancing the ruminal synthesis of CLA and in modifying the FA and terpenoid profiles of milk and “Bitto” cheese. Nevertheless, neither the FA nor the terpenoid profiles revealed here can be considered as “unique” to “Bitto” cheese and, for this reason, they can hardly be assumed to be biomarkers for defining a specific relationship among grazing area, milk and “Bitto” cheese. They better represent the chemical fingerprint of the cow feeding, adopted in mountain areas.  相似文献   

18.
A low-field (LF) 1H NMR T2 relaxation and 23Na/1H MRI study was performed on Atlantic salmon to study the effect of ante-mortem handling stress and rigor mortis on muscle water properties and subsequent post-rigor salting. Compared to rested fish, exhausted fish exhibited a more rapid and stronger development of rigor mortis. This resulted in significant differences in post-rigor water-holding capacity and salt uptake. By LF NMR T2 relaxation analysis significant differences in water distribution according to (1) ante-mortem handling, (2) fillet location, and (3) brine salting were detected. Furthermore, 23Na MRI revealed differences between the two treatments in fillet salt distribution, where the salt penetration in exhausted fillets was more pronounced. By combining 1H and 23Na MR images, the salt diffusion and distribution seemed to be highly affected by the distribution of fat.  相似文献   

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