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1.
Integrated, organic, and soil-less production systems are the principal production practices that have emerged to encourage more sustainable agricultural practices and safer edible plants, reducing inputs of plaguicides, pesticides, and fertilizers. Sweet peppers grown commercially under integrated, organic, and soil-less production systems were compared to study the influence of these sustainable production systems on the microbial quality and bioactive constituents (vitamin C, individual and total carotenoids, hydroxycinnamic acids, and flavonoids). The antioxidant composition of peppers was analyzed at green and red maturity stages and at three harvest times (initial, middle, and late season). Irrigation water, manure, and soil were shown to be potential transmission sources of pathogens to the produce. Coliform counts of soil-less peppers were up to 2.9 log units lower than those of organic and integrated peppers. Soil-less green and red peppers showed maximum vitamin C contents of 52 and 80 mg 100 g(-1) fresh weight (fw), respectively, similar to those grown in the organic production system. Moreover, the highest content of total carotenoids was found in the soil-less red peppers, which reached a maximum of 148 mg 100 g(-1) fw, while slightly lower contents were found in integrated and organic red peppers. Hydroxycinnamic acids and flavonoids represented 15 and 85% of the total phenolic content, respectively. Total phenolic content, which ranged from 1.2 to 4.1 mg 100 g(-1) fw, was significantly affected by the harvest time but not by the production system assayed. Soil-less peppers showed similar or even higher concentrations of bioactive compounds (vitamin C, provitamin A, total carotenoid, hydroxycinnamic acids, and flavonoids) than peppers grown under organic and integrated practices. Therefore, in the commercial conditions studied, soil-less culture was a more suitable alternative than organic or integrated practices, because it improved the microbial safety of sweet peppers without detrimental effects on the bioactive compound content.  相似文献   

2.
Sweet peppers (Capsicum annuum L.) cv. Vergasa have been studied at four maturity stages (immature green, green, immature red, and red). The individual phenolics (hydroxycinnamic acids and flavonoids), vitamin C (ascorbic acid and dehydroascorbic acid), and individual carotenoids were characterized and quantified. Five hydroxycinnamic derivatives and 23 flavonoids were characterized and quantified from the pericarp of sweet pepper by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Identification was carried out by their UV spectra, chromatographic comparisons with authentic markers, identification of hydrolysis products, and tandem mass spectrometry analysis. Hydroxycinnamic derivatives, O-glycosides of quercetin, luteolin, and chrysoeriol, and a large number of C-glycosyl flavones have been characterized. Some of these compounds were found for the first time in nature. Clear differences in the individual and total phenolic content were detected between the different maturity stages. Immature green pepper had a very high phenolic content while green, immature red, and red ripe peppers showed a 4-5-fold reduction. Ascorbic acid was the main form of vitamin C, and its content increased as the pepper reached maturity. The red ripe stage had a relevant impact on the carotenoids content. Thus, immature green peppers showed the highest content of polyphenols, while red ripe fruits had the highest content of vitamin C and provitamin A.  相似文献   

3.
Carotenoids in white- and red-fleshed loquat fruits   总被引：2，自引：0，他引：2  
Fruits of 23 loquat ( Eriobotrya japonica Lindl.) cultivars, of which 11 were white-fleshed and 12 red-fleshed, were analyzed for color, carotenoid content, and vitamin A values. Color differences between two loquat groups were observed in the peel as well as in the flesh. beta-Carotene and lutein were the major carotenoids in the peel, which accounted for about 60% of the total colored carotenoids in both red- and white-fleshed cultivars. beta-Cryptoxanthin and, in some red-fleshed cultivars, beta-carotene were the most abundant carotenoids in the flesh, and in total, they accounted for over half of the colored carotenoids. Neoxanthin, violaxanthin, luteoxanthin, 9- cis-violaxanthin, phytoene, phytofluene, and zeta-carotene were also identified, while zeaxanthin, alpha-carotene, and lycopene were undetectable. Xanthophylls were highly esterified. On average, 1.3- and 10.8-fold higher levels of colored carotenoids were observed in the peel and flesh tissue of red-fleshed cultivars, respectively. The percentage of beta-carotene among colored carotenoids was higher in both the peel and the flesh of red-fleshed cultivars. Correlations between the levels of total colored carotenoids and the color indices were analyzed. The a* and the ratio of a*/ b* were positively correlated with the total content of colored carotenoids, while L*, b*, and H degrees correlated negatively. Vitamin A values, as retinol equivalents (RE), of loquat flesh were 0.49 and 8.77 microg/g DW (8.46 and 136.41 microg/100 g FW) on average for white- and red-fleshed cultivars, respectively. The RE values for the red-fleshed fruits were higher than fruits such as mango, red watermelon, papaya, and orange as reported in the literature, suggesting that loquat is an excellent source of provitamin A.  相似文献   

4.
Folic acid (pteroylmonoglutamic acid) is used in enriched foods; however, very little folic acid occurs naturally in fruits and vegetables. For the U.S. Department of Agriculture's National Food and Nutrient Analysis Program, a number of fruits and vegetables have been assayed for endogenous folates, by a liquid chromatography-mass spectrometry method, to evaluate the accuracy of existing data for total folate determined by standard microbiological analysis. Folate in red and green sweet peppers (Capsicum annuum) differed notably (70.2 and 20.7 microg/100 g, respectively) and exceeded existing values determined by microbiological assay (18 and 11 microg/100 g, respectively). 5-Methyltetrahydrofolate was the predominant vitamer, but a significant amount of 5-formyltetrahydrolfolate and some 10-formylfolate were present. These findings may assist in making dietary recommendations or developing research diets related to folate. The data from this study have been used to update the folate values in release 19 of the USDA Nutrient Database for Standard Reference.  相似文献   

5.
A study was conducted to investigate the change in quality attributes of red pepper (paprika) (Capsicum annuum L. var. Km-622) as a function of ripening and some technological factors. Of quality attributes, carotenoids and bioantioxidants (ascorbic acid and tocopherols) have been studied. It was found that the dynamics of fruit ripening with regard to carotenoids and bioantioxidants was influenced to a considerable extent by weather conditions of the production season. A rainy and cool season yielded fruits with more beta-carotene but less diesters of red xanthophylls as compared to those produced in a relatively dry and warm season. The ripening stage at harvest was found to affect the quality of paprika. Harvest at unripe stages (color break or faint red) resulted in a high accumulation of dehydroascorbic acid in the overripe fruits, whereas de novo biosynthesis of carotenoids and tocopherols was partially retarded. Application of pre-drying centrifugation resulted in a marked loss of ascorbic acid, and as a consequence, carotenoid stability was impaired during the storage of ground paprika. Sugar caramelization caused dry pods and ground paprika to retain more pigments and tocopherol as compared to those from control or centrifuged red pepper samples. During the storage of ground paprika, color stability was improved by grinding the seeds with the pericarp.  相似文献   

6.
One nonanthocyanin-accumulating (Ailsa Craig) and three anthocyanin-accumulating tomato genotypes (Anthocyanin fruit type, Atroviolaceum, and Sun Black) were analyzed to assess differences in their carotenoid and anthocyanin levels and color and to evaluate the effects of nutrient solutions with different salt concentrations on these parameters. The carotenoid content of control Atroviolaceum tomatoes was ca. 2-2.5-fold higher relative to the other two types, and the color of its puree could be visually distinguished from those of other genotypes. Salinity stress led in some cases to a 2-3-fold increase in the lycopene content. Saline treatment increased the accumulation of total anthocyanins in fruits of Sun Black (2-fold increase), while it reduced it in fruits of Anthocyanin (10-fold decrease). In general, the treatment increased the differences in color of different purees. These results indicate that salinity stress can lead to similar or higher increases in tomato carotenoids than those achieved by genetic engineering. In addition, these changes were accompanied by visually discernible color differences in tomato products. Our findings show the considerable potential of exploiting saline soils to obtain tomatoes with higher levels of secondary metabolites like carotenoids and anthocyanins.  相似文献   

7.
In order to optimise land use systems, to prevent erosion-induced degradation and to restore the degraded red soils in subtropical China, five cropping systems and four agroforestry systems were conducted in red soils with a slope of 7° from 1993 to 1995. The results showed that erosion risk period occurred from April to June, and the annual runoff and the losses of soil and nutrients with sediment were alarming for two conventional farming systems, whereas they were negligible for the farming systems with ridge tillage. Enrichment ratios of the lost soils from erosion were more than 1.20 for all nutrients with much higher values for hydrolysable N and organic matter. Compared with the control, the alley cropping systems also distinctly decreased runoff by 30% or 50%. However, the coverage of soil surface varied with alley cropping systems for the competition of nutrients and soil water, which made a profound difference in runoff. The cropping systems of sweet potato intercropped with soybean, the alley cropping systems and the measures of mulching and ridge tillage were the alternatives for red soil reclamation so as to prevent erosion-induced degradation.  相似文献   

8.
Fruits and leaves from different cultivars of thornless blackberry (Rubus sp.), red raspberry (Rubus idaeus L.), black raspberry (Rubus occidentalis L.), and strawberry (Fragaria x ananassa D.) plants were analyzed for total antioxidant capacity (oxygen radical absorbance capacity, ORAC) and total phenolic content. In addition, fruits were analyzed for total anthocyanin content. Blackberries and strawberries had the highest ORAC values during the green stages, whereas red raspberries had the highest ORAC activity at the ripe stage. Total anthocyanin content increased with maturity for all three species of fruits. Compared with fruits, leaves were found to have higher ORAC values. In fruits, ORAC values ranged from 7.8 to 33.7 micromol of Trolox equivalents (TE)/g of fresh berries (35. 0-162.1 micromol of TE/g of dry matter), whereas in leaves, ORAC values ranged from 69.7 to 182.2 micromol of TE/g of fresh leaves (205.0-728.8 micromol of TE/g of dry matter). As the leaves become older, the ORAC values and total phenolic contents decreased. The results showed a linear correlation between total phenolic content and ORAC activity for fruits and leaves. For ripe berries, a linear relationship existed between ORAC values and anthocyanin content. Of the ripe fruits tested, on the basis of wet weight of fruit, cv. Jewel black raspberry and blackberries may be the richest source for antioxidants. On the basis of the dry weight of fruit, strawberries had the highest ORAC activity followed by black raspberries (cv. Jewel), blackberries, and red raspberries.  相似文献   

9.
The contents of sugars, organic acids, total phenolic content, and the antioxidant activity were quantified in the flesh of red beet from conventional (CON), integrated (INT), organic (ORG), biodynamic (BD), and control farming systems using established methods. Significant differences were measured for malic acid, total phenolic content (TPC), and total antioxidant activity, where malic acid content ranged from 2.39 g kg(-1) FW (control) to 1.63 g kg(-1) FW (CON, ORG, and INT). The highest TPC was measured in BD and control samples (0.677 and 0.672 mg GAE g(-1), respectively), and the lowest in CON samples (0.511 mg GAE g(-1)). Antioxidant activity was positively correlated with TPC (r2=0.6187) and ranged from 0.823 μM TE g(-1) FW to 1.270 μM TE g(-1) FW in CON and BD samples, respectively, whereas total sugar content ranged from 21.03 g kg(-1) FW (CON) to 31.58 g kg(-1) FW (BD). The importance of sugars, organic acids, phenols, and antioxidants for human health, as well as for plant resilience and health, gained from this explorative study, is discussed and put into perspective.  相似文献   

10.
Fresh peppers (Capsicum annuum L., variety California) in their green and red ripe stages were stored at 20 degrees C for 7 and 19 days to determine the effects of storage on whole fruit antioxidant capacity (TAA) and ascorbate (ASC) content, as well as on some antioxidant enzyme activities, such as catalase (CAT), superoxide dismutase (SOD), and those of the ASC-glutathione cycle. At least one Mn-SOD, two Fe-SODs, and three CuZn-SODs were detected in the fruit extract after native polyacrylamide gel electrophoresis. All of the SOD isozymes and glutathione reductase had higher activity levels in the red control fruits than in the green fruits, whereas the activities of monodehydroascorbate and dehydroascorbate reductase were higher in green fruits. Ascorbate peroxidase (APX) was found to be similar in both fruits. SODs, CAT, and APX seem to be involved in pepper fruit ripening and senescence during storage at 20 degrees C, perhaps influencing the active oxygen species levels in the fruit. TAA, as well as the ASC content, was higher in red peppers than in green, and storage increased the ASC in both green and red fruits.  相似文献   

11.
Kernels of two carotenoid‐rich cultivars, sweet corn Jingtian 5 and field corn Suyu 29, were compared in terms of carotenoid composition during corn kernel development. The results showed that eight principal carotenoids were characterized by HPLC with diode array detection and atmospheric pressure chemical ionization tandem mass spectrometry with a C30 column. During kernel development, there was a similar trend in the change of total carotenoids for both corn cultivars, and the variation of individual carotenoids was also somewhat similar; violaxanthin, zeaxanthin, lutein, α‐cryptoxanthin, and β‐cryptoxanthin contents had upward trends, whereas neoxanthin content declined all the time, and α‐carotene and β‐carotene had no significant changes. However, the highest levels of the major carotenoids lutein (41.61 µg/g, dry weight) and zeaxanthin (39.59 µg/g, dry weight) obtained in field corn Suyu 29 during the milk stage were higher than those in sweet corn Jingtian 5, whereas the other individual carotenoid levels were significantly lower. Compared with the grain color, highly significant positive correlations were observed between zeaxanthin, lutein, and violaxanthin contents and deeper yellow/orange coloration indicators for field corn Suyu 29, but these relationships were weak for sweet corn Jingtian 5. Potential genetic variation might exist for carotenoid accumulation in sweet and field corn kernels.  相似文献   

12.
In the present study, three pea Greek landraces Schinousa (AUASCHIN001), Andros (AUAANDRO001), and Amorgos (AUAAMORG001), and the commercial variety Onward were grown following either conventional or organic farming practices. The main objective of the study was to assess the suitability of these three landraces for organic cultivation as compared with a standard commercial variety. The total fresh pod yield produced by AUASCHIN001 and AUAAMORG001 was significantly lower than that obtained from ‘Onward’ and AUAANDRO001. Furthermore, the three landraces exhibited a higher competition to weeds than the commercial variety. Under organic farming conditions, AUASCHIN001 and AUAAMORG001 produced appreciably less shoot biomass than ‘Onward’ and this resulted in commensurate decreases in the total amount of BNF (biological nitrogen fixation) in their plant tissues, although the percentage of nitrogen (N) fixed from the atmosphere was significantly lower in ‘Onward’. AUAANDRO001 rendered the highest amounts of BNF in the organic farming systems, which was similar to that produced by ‘Onward’ in the conventional system. These results indicate that the tested landraces and especially AUAANDRO001 are more adaptable to low soil N levels and high weed competition, and thus they are more suitable for organic cultivation than ‘Onward’ which performs best in conventional cropping systems.  相似文献   

13.
The development and ripening process of sweet cherry (Prunus avium L. cv. 4-70) on the tree was evaluated. For this purpose, 14 different stages were selected in accordance with homogeneous size and color. Some parameters related to fruit quality, such as color, texture, sugars, organic acids, total antioxidant activity, total phenolic compounds, anthocyanins, and ascorbic acid were analyzed. The results revealed that in sweet cherry, the changes in skin color, glucose and fructose accumulation, and softening process are initiated at early developmental stages, coinciding with the fast increase in fruit size. Also, the decrease in color parameter a was correlated with the greatest accumulation of total anthocyanins. Ascorbic acid, total antioxidant activity (TAA), and total phenolic compounds decreased during the early stages of sweet cherry development but exponentially increased from stage 8, which coincided with the anthocyanin accumulation and fruit darkening. TAA showed positive correlations (r(2) = 0.99) with both ascorbic acid and total phenolic compounds and also with the anthocyanin concentration from stage 8. Taking into account the reduced shelf life of sweet cherry and to ensure that these fruits reach consumers with the maximum organoleptic, nutritional, and functional properties, it is advisable to harvest sweet cherries at stage 12 of ripening.  相似文献   

14.
Anthocyanins and carotenoids are natural pigments responsible for the color of vegetables and fruits, and they are also bioactive compounds, both demonstrating important biological, therapeutic, and preventative properties. Considering the biodiversity of edible fruits, high performance liquid chromatography coupled to photodiode array and mass spectrometry detectors (HPLC-PDA-MS) was used to establish the composition of carotenoids and anthocyanins from dovyalis and tamarillo fruits. Ten anthocyanins and 26 carotenoids were found in dovyalis, whereas tamarillo showed 3 anthocyanins and 17 carotenoids. Higher contents of anthocyanins and carotenoids were found in dovyalis, 42.0 and 6.6 mg/100 g, respectively, as compared to tamarillo fruits with 8.5 and 4.4 mg/100 g, respectively. Although these fruits belong to different families, delphinidin 3-rutinoside and beta-cryptoxanthin were found to be, respectively, the major anthocyanin and carotenoid in both fruits.  相似文献   

15.
通过田间试验比较了有机、特别与常规栽培对8种蔬菜土壤基本养分和土壤酶活性的影响。结果表明,与常规栽培相比,有机栽培和特别栽培能够提高土壤有机质、全氮、速效磷和速效钾含量,改良酸性土壤,并显著提高了土壤酶活性。有机栽培蔬菜土壤过氧化氢酶、脲酶、转化酶和酸性磷酸酶活性均显著高于常规栽培。特别栽培的各项土壤指标基本介于有机和常规之间。研究表明有机栽培能够提高土壤养分和土壤酶活性。  相似文献   

16.
Stay-green mutants have been very useful for elucidating the chlorophyll catabolism pathway in higher plants. In the present study the possible relationship between the retention/catabolism of chlorophylls and the carotenogenic process taking place in ripening Capsicum annuum (L.) fruits has been investigated. Phytylated, dephytylated and oxidized chlorophyll derivatives, and total and individual carotenoids were analyzed over the whole ripening period. In general terms, the biosynthesis of carotenoid pigments taking place during the ripening of C. annuum fruits is identical in both red and stay-green lines, so that the carotenogenic process is independent of the retention of chlorophylls. However, it has been found that the carotenogenesis is slowed in the stay-green lines. Therefore, although the catabolism of chlorophylls and biosynthesis of carotenoids seem to be separate processes, the fact that they are taking place in the chloroplast/chromoplast suggests that some kind of interaction between the two processes may occur at different levels. Plastids corresponding to the wild genotype (red color fruit phenotype) show high plastoglobuli density and thylakoids are almost absent, whereas in the case of stay-green phenotype, thylakoids and plastoglobuli coexist in the same plastid (chlorochromoplasts). The role of carotenoid pigments on the physiological mechanism for protecting the preserved thylakoid structures is discussed.  相似文献   

17.
Most claims that organic produce is better tasting and more nutritious than nonorganic (conventional) produce are largely unsubstantiated. This is due mainly to a lack of rigor in research studies matching common production variables of both production systems, such as microclimate, soil type, fertilizer elemental concentration, previous crop, irrigation source and application, plant age, and cultivar. The aforementioned production variables common to both production systems were matched for comparison of Texas commercially grown conventional and certified organic Rio Red red-fruited grapefruit. Whole grapefruits from each production system were harvested between 800 and 1000 h at commercial early (November), mid- (January), and late season (March) harvest periods for three consecutive years. Within each harvest season, conventional and organic whole fruits were compared for marketable qualities (fruit weight, specific gravity, peel thickness, and peel color), and juices were compared for marketable qualities (specific gravity, % juice, and color), human health-bioactive compounds (minerals, ascorbic acid, lycopene, sugars, pectin, phenols, and nitrates), and consumer taste intensity and overall acceptance. Conventional fruit was better colored and higher in lycopene, and the juice was less tart, lower in the bitter principle naringin, and better accepted by the consumer panel than the organic fruit. Organic fruit had a commercially preferred thinner peel, and the juice was higher in ascorbic acid and sugars and lower in nitrate and the drug interactive furanocoumarins.  相似文献   

18.
不同蔬菜生产模式对日光温室土壤质量的影响   总被引：3，自引：0，他引：3  
有机农业作为常规农业的一种替代模式,其对土壤及作物的影响研究逐渐受到学术界的关注。该文通过对日光温室有机、无公害和常规生产模式的比较试验,分析有机生产模式对土壤养分、土壤微生物碳氮以及土壤酶活性的影响。结果表明,经过6年的试验,有机生产模式可显著提高土壤全碳、全氮含量以及土壤微生物量碳、氮含量,并提高土壤主要酶的活性,各项指标均表现为有机模式优于无公害模式优于常规模式。有机生产模式能够显著提高土壤质量,有利于土壤的可持续利用。3种生产模式下夏茬番茄产量有机模式高于无公害模式高于常规模式,且随着种植年限的增加有机模式秋茬作物产量呈增加趋势。  相似文献   

19.
The developmental patterns of carotenoids in Hamlin, Earlygold (an early-maturing selection), and Budd Blood sweet orange juices were studied during the September to mid-January period of the 1996-97 and 1997-98 seasons. The carotenoid concentration of Earlygold increased by as much as 4.9 times during the color development compared to 3.9 times in Hamlin and 4.5 times in Budd Blood juice in the same period. For the profiles of carotenoid pigment, dramatic changes occurred among the pigments that were present in high concentrations at the beginning of the season, with lutein and violaxanthin noted as the predominant pigments in Hamlin fruit. A marked increase in the percentage of beta-cryptoxanthin allowed it to become a major pigment in the late stage of maturation. The color development in the new cultivar Earlygold was especially notable, reaching the 36 color number, which is grade A, by late October to mid-November whereas Hamlin juice did not reach this grade A color number until January. Budd Blood juice was similar in carotenoid pigment content and seasonal changes to Hamlin juice, but also, the development of red anthocyanin pigment in January significantly increased juice color.  相似文献   

20.
This study conducted a long-term field trial to evaluate the effects of three farming methods (i.e., conventional farming, organic farming, and intermediate farming) on soil fertility and plant growth under a crop rotation of vegetables, sweet corn, and rice. The nitrogen (N) uptake of crops grown with chemical fertilizers (CFs) and organic fertilizers was also compared carefully over 7 consecutive years. The results revealed that only a fraction of the nitrogen N in chicken manure compost was available to crops immediately following application. Therefore, the fresh weight production and absorption of N by amaranth, water convolvulus, and sprouting broccoli plants were relatively minimal compared to those grown with chemical N fertilizers. However, the amount of N from the chicken manure compost met the nutrient requirements of rice and sweet corn. Application of chicken manure compost increased the accumulation of soil organic matter (SOM) and available phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) content, which is essential for enhancing soil quality. Because of the rapid decomposition of rapeseed seed meal (RSM), most of the N in RSM was mineralized immediately following application, which induced the rapid growth of leafy vegetables and increased yields. Application of compost with chemical fertilizers not only results in yields as high as those from pure chemical fertilizer treatment, but also improves SOM accumulation and soil fertility.  相似文献   

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