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1.
Mechanochemical-assisted extraction (MCAE) method was developed for extraction of flavonoids and terpene trilactones from Ginkgo leaves. The MCAE parameters and the antioxidant activities of Ginkgo biloba extract (GBE) were investigated. Through response surface methodology design experiments, the processing conditions were optimized as follows: amount of solid reagent (NaHCO3) 21%, milling time 7.5 min, and ratio of solvent to solid 33 mL/g. Under these conditions, the yields of flavonoids and terpene trilactones in GBE were 6.83 mg/g and 1.72 mg/g, respectively. Compared with the heat reflux extraction method, the yields of flavonoids and terpene trilactones are higher, and the extraction time was significantly shortened. What is more, the MCAE method only used water as solvent. GBE of MCAE possessed notable antioxidant activity with IC50 values of 11.7 and 13.8 μg/mL, respectively.  相似文献   

2.
The demand for food is increasing, not only to meet food security for growing populations, but also to provide more nutritious food, rich in good quality proteins and nutraceutical compounds. The amaranth (Amaranthus hypochondriacus) plant, in addition to its high nutritive and nutraceutical characteristics, has excellent agronomic features. The objective of the present study was to analyze some physical and proximal-nutritional properties of amaranth seeds obtained from different varieties grown in arid zones and characterize their phenolic acids and flavonoids. Two commercial (Tulyehualco and Nutrisol) and two new (DGETA and Gabriela) varieties of A. hypochondriacus were grown at the Mexican Highlands zone. Tulyehualco and DGETA varieties had higher seed yield of 1475 and 1422 kg ha−1, respectively, comparable to corn and soybean production in agricultural areas. Gabriela had the highest protein content of 17.3%, but all varieties had an adequate balance of essential amino acids. Polyphenols as rutin (4.0–10.2 μg g−1 flour) and nicotiflorin (7.2–4.8 μg g−1 flour) were detected. Amaranth can be cultivated in arid zones where commercial crops cannot be grown; the seeds besides their well known nutritive characteristics could be a source of phenolic compounds of high antioxidant properties.  相似文献   

3.
Castor plant (Ricinus communis L.) produces a very important oil for chemical and biofuel industries. However, doubts remain about what the best plant arrangement is to obtain the maximum yield of seeds and oil from short height castor genotypes cultivated in higher plant population. This study evaluated two castor genotypes (FCA-PB and IAC 2028) in 5 plant arrangements (row spacing × in-row spacing): 0.90 m × 0.44 m (traditional), 0.90 m × 0.20 m, 0.75 m × 0.24 m, 0.60 × 0.30 m, and 0.45 m × 0.40 m, in spring-summer and fall-winter cropping seasons in Botucatu, São Paulo State, southeastern Brazil. The traditional plant arrangement comprised an initial plant population of 25,000 plants ha−1, while the others comprised 55,000 plants ha−1. The IAC 2028 genotype presented the greatest plant height, first raceme insertion height, basal stem diameter, number of fruits per raceme and 100 seed weight; however, seed yield and seed oil content were equal between genotypes. Wider stems and higher number of racemes per plant and fruits per raceme were observed with a 0.90 m × 0.44 m plant arrangement, but due to the lowest plant population (25,000 plants ha−1) in this plant arrangement, the higher values of the yield components mentioned above did not result in higher yield. The higher plant population (55,000 plants ha−1) by narrower row spacings (0.45 or 0.60 m) combination produced a higher castor seed yield. The effect of plant arrangement was more intense in the spring-summer cropping season.  相似文献   

4.
Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 μM TDZ. The Induced shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM 6-benzyl aminopurine (BA), and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 μM BA and 8.5 μM IAA. The elongated shoots could be rooted on half-strength MS medium with 15 μM IBA, 11.4 μM IAA and 5.5 μM NAA with more than 90% survival rate.  相似文献   

5.
柠檬商品化鲜果、柠檬香精油、柠檬浓缩汁、柠檬果胶、柠檬苦素及柠檬休闲食品是柠檬加工综合利用的重要产品。本文主要概述了柠檬加工综合利用的研究进展,并提出了目前国内柠檬加工利用研究的发展方向。  相似文献   

6.
Starch was isolated from 98 hard red winter (HRW) wheat and 99 hard red spring (HRS) wheats. Granule size/volume distributions of the isolated starches were analyzed using a laser diffraction particle size analyzer. There were significant differences in the size distribution between HRW and HRS wheats. The B-granules (<10 μm in diameter) occupied volumes in the range 28.5–49.1% (mean, 39.9%) for HRW wheat, while HRS wheat B-granules occupied volumes in the range 37.1–56.2% (mean, 47.3%). The mean granule sizes of the distribution peaks less than 10 μm in diameter also showed a significant difference (HRW, 4.32 vs. HRS, 4.49 μm), but the mean sizes of the distribution peaks larger than 10 μm were not significantly different (21.54 vs. 21.47 μm). Numerous wheat and flour quality traits also showed significant correlation to starch granule size distributions. Most notably, protein content was inversely correlated with parameters of B-granules. Crumb grain score appeared to be affected by starch granule size distribution, showing significant inverse correlations with B-granules. Furthermore, the linear correlations were improved when the ratio of B-granules to protein content was used, and the polynomial relation was applied. There also appeared to be an optimum range of B-granules for different protein content flour to produce bread with better crumb grain.  相似文献   

7.
8.
Harvesting wheat (Triticium aestivum L.) for forage or leaving it for grain is the main decision uncertainty growers face in semi-arid regions during mid-season. To facilitate decision-making, a decision support system (DSS) has recently been proposed that requires information about crop water and nutritional status during spike emergence. Though remote sensing has been used to provide site-specific crop status information, a spectral vegetation index is needed to ensure that the information has been acquired during spike emergence. The objective of this study was to propose a spectral index sensitive to spike emergence and validate its suitability across different commercial farm fields by using ground spectral measurements and multispectral satellite imagery. To develop the index, controlled experiments with commonly grown wheat varieties were conducted during the 2004/2005 and 2005/2006 growing season in the agricultural area of the northern Negev desert of Israel. The experiments showed that spike emergence correlated most strongly (r = 0.7, p < 0.05) with spectral changes near the 1.2 μm water absorption feature in contrast to the band at 1.1 μm which appeared to be only weakly correlated. Thus, the spike emergence sensitive band at 1.2 μm has been combined with the insensitive band at 1.1 μm as reference to form the ratio-based normalized heading index (NHI). Experimental data were then used to establish an index threshold that helps separate data acquired before and after spike emergence. The proposed NHI was able to identify spike emergence with a classification accuracy varying between 53 and 83%. Accuracy was influenced by season, and whether narrow or broad spectral bands were used. Validation of the index in commercial farm fields in Israel and the United States showed that the classification accuracy was similar for ground spectral measurements and the advanced land imager (ALI) satellite imagery. These results suggest that the NHI is suited for identifying the onset of heading throughout wheat-growing areas without the need for characterizing seasonal trends.  相似文献   

9.
Castilleja tenuiflora is a highly valued medicinal plant that grows in pine-oak woods in Mexico. In this study, we identified for the first time verbascoside and isoverbascoside as the major phenylethanoid glycosides (PhGs) in C. tenuiflora. These compounds have proven biological activities, including anti-inflammatory, antioxidant, and cytotoxic activities, which may be related to the traditional uses of this plant. We developed a reverse-phase high-performance liquid chromatography (RP-HPLC) procedure to analyze PhGs, and determined their concentrations in various different tissues of wild plants. Verbascoside accumulated mainly in roots and inflorescences (9.23 and 7.88 mg g−1 dry biomass, respectively), while isoverbascoside accumulated mainly in the roots (7.13 mg g−1 dry biomass). To provide an alternative source of material for production of bioactive compounds, we established in vitro adventitious root cultures in which roots were grown in B5 medium containing either 10 μM indole 3-acetic acid (IAA) or 10 μM α-naphthaleneacetic acid (NAA). The greatest dry biomass yield (30 g L−1) was achieved at 30 days after transfer of roots into IAA-containing medium. The highest specific yields of PhGs were also obtained using this auxin; the maximum level of verbascoside was 14.62 mg g−1 dry root biomass (438.6 mg L−1) at 30 days after root transfer, and the maximum yield of isoverbascoside was 37.32 mg g−1 dry root biomass (522.48 mg L−1) at 23 days after root transfer. Adventitious root cultures of C. tenuiflora are a promising system for further studies on scale-up and phenylethanoid glycosides biosynthesis.  相似文献   

10.
The changes in the amount and composition of suberin monomers of Scots pine outer bark, which is grown natively in Turkey, was investigated as a function of growing altitude. Samples were taken from every 100 m to 1300 m which was the highest point of the sampling area. While the total amount of suberin monomers is varied within the range 17.56-47.20 mg/g, there was no correlation between total amount and altitude. Total amount of alkanols of suberin monomers decreased when the altitude increased. Alcohol 24:0 was seen as the dominant constituent and its amount decreased from 100 m to 1300 m. There was not a clear change in the total amount of alkanoic, dioic and hydroxy acids. Acid 1,18-hydroxy-18:1 and acid 1,18-dioic-18:1 were determined as the main compounds in all samples.  相似文献   

11.
Wastage of agricultural chemicals and ensuing environmental pollution is an issue, where ineffective spray deposition is a major concern with conventional pesticide application methods. Electrostatic spraying is known to be one of the most effective methods to improve leaf abaxial (underside) surface deposition, overall deposition, and distribution on the plant targets. Deposition of charged sprays on leaf abaxial and adaxial (upper) surfaces as influenced by the spray charging voltage (system), application speed (operational), target height and orientation (target) parameters was studied in the laboratory. An air-assisted electrostatic induction spray charging system attached to a moving carriage was used to apply charged spray at uniform application (ground) speeds. Spray deposition (101–71 μm NMD), determined using a fluorescent tracer technique increased with charging (0–5.5 mC kg−1) on leaf abaxial and decreased with charging on adaxial surface. The deposition was higher on abaxial (0.66–1.33 μg cm−2) at 30° below (horizontal plane) and on adaxial (0.78–1.79 μg cm−2) at 0° (horizontal) target orientation for lower (0.278 m s−1) application speed. At all target heights, abaxial deposition increased with charging voltage (0–4.0 kV) for medium application speed (0.417 m s−1) and adaxial deposition decreased with charging voltage for lower application speed (0.278 m s−1). The medium application speed with higher charging voltage was optimum for abaxial and adaxial deposition. The droplet velocity and charging voltage were the key factors for obtaining desired spray deposition on targets. All the selected factors including target orientation (O), application speed (S), target surface (L), and charging voltage (V), and their interactions except between O and S were significant at lower (0.35 m) and medium (0.65 m) target heights. All the factors and their interactions except between O and V were significant at higher (0.95 m) height. Electrostatically charged spray improved the underside (abaxial) and overall deposition. The deposition was substantially influenced by factors such as charging voltage, application speed, plant target height, and target orientation.  相似文献   

12.
The effects of three independent variables: solvent polarity, temperature and extraction time on the antioxidant capacity, total phenolic content and phenolic acid composition in extracts obtained from sunflower shells before and after enzymatic treatment were studied. Response surface methodology based on three-level, three-variable Box-Behnken design was used for optimization of extraction parameters and evaluation of their effect on antioxidant capacity and total phenolic content in shell extracts.The average antioxidant capacities of extracts from sunflower shells without enzymatic treatment (368.1-1574.4 μmol TE/100 g) were higher than those for cellulolytic and pectolytic enzymes-treated shells (222.7-1419.0 and 270.7-1570.7 μmol TE/100 g, respectively). The content of total phenolic compounds ranged between 58.2-341.2 mg CGA/100 g, 26.7-277.3 mg CGA/100 g and 51.4-301.5 mg CGA/100 g for extracts obtained from shells without enzyme and treated with cellulolytic and pectolytic enzymes, respectively. Total phenolic content (TPC) in the studied shell extracts correlated significantly (p < 0.0001) positively with their antioxidant capacity determined by the ferric reducing antioxidant power (FRAP) method (r = 0.9275). Results of FRAP, TPC and phenolic acid composition in the studied shell extracts depend on the extraction conditions (solvent polarity, temperature, time), but they are independent on the addition of enzyme solutions. The antioxidant capacity and total phenolic content in the resulting extracts increased with a line in extraction temperature and solvent polarity.  相似文献   

13.
A simple and rapid method for micropropagation of succulent, salt accumulator and extreme halophyte Salicornia brachiata has been established for the first time using shoot tips and nodes. Individually, BA showed significant response compared to Kn and in combinations, improved shoot proliferation was observed with BA + NAA than BA + 2,4-D, however no significant response was observed with BA + IAA. Percentage of shoot response significantly increased with NaCl treatment in the combination of BA + NAA while BA + 2,4-D + NaCl combination showed reduced shoot proliferation followed by demises of most of cultures. Efficient shoot proliferation was observed with combinations BA (8.9 μM) + NAA (5.37 μM) + NaCl (500 mM) and BA (13.3 μM) + NAA (5.37 μM) + NaCl (250 mM) indicating that NaCl is required for the micropropagation. The developed method will facilitate functional analysis of novel salt responsive gene(s) isolated from S. brachiata and propagation of industrially important elite accessions.  相似文献   

14.
Durum wheat grains are used for producing food, such as pasta or couscous. The grain mechanical properties which are linked to its internal micro-structure (i.e. endosperm porosity) are known to determine its ability to produce semolina during milling. The proportion of grains having porous endosperm in a batch appears therefore as a critical quality factor for the durum wheat value chain. Our objective was to investigate the ability of X-ray micro-tomography (μCT) method to describe the porous or vitreous counterpart structures in the endosperm of durum wheat grains. We selected two different durum wheat samples displaying vitreous or partially porous endosperms. The grains were analyzed using μCT at two pixel sizes (1 μm or 7 μm). The μCT data collected at 7 μm pixel size were used for qualitative classification of grains according to apparent distribution curve of the porosity parameters. Analysis of μCT images at 1 μm pixel size allowed us to propose pore size classification in the vitreous and porous parts of the endosperm in three durum wheat grain. Results are used to better describe the durum-wheat endosperm microstructure, but requires long scanning periods.  相似文献   

15.
Litchi downy blight caused by Peronophythora litchii is a devastating disease of litchi plants in China. Control of litchi downy blight requires numerous fungicide applications. A new carboxylic acid amide (CAA) fungicide, mandipropamid, was examined for its in vitro effects on multiple asexual stages of four single-sporangium P. litchii isolates and protective activity against downy blight in detached fruit assays. Though mandipropamid did not affect discharge of zoospores from sporangia, it strongly inhibited mycelial growth (mean EC50 = 0.0048 μg ml−1), sporangia production (mean EC50 = 0.0032 μg ml−1), germination of encysted zoospores (mean EC50 = 0.0023 μg ml−1), and germination of sporangia (mean EC50 = 0.0061 μg ml−1). On detached fruit, 0.39, 1.56 and 6.25 μg ml−1 of mandipropamid were superior in reducing downy blight compared to metalaxyl and flumorph, however, the 25 μg ml−1 application rate was necessary for all three CAA fungicides to completely inhibit the disease. In 2007, 100 isolates from Fujian, Guangdong, and Guangxi Provinces of China were characterized for the baseline sensitivity to mandipropamid. The isolates obtained from different provinces showed similar baseline sensitivities to mandipropamid. Baseline sensitivities formed a unimodal curve with mean EC50 values of 0.0055 ± 0.0012 μg ml−1 for inhibition of mycelial growth. The described baseline sensitivities of P. litchii populations will be useful for monitoring possible shifts in sensitivity to mandipropamid.  相似文献   

16.
Jackfruit is an underutilized edible fruit in the tropics and subtropics. The aim of this study was to produce wine from jackfruit pulp and to evaluate the total phenolic and flavonoid contents and antioxidant properties of the wine. The ability of scavenging free radicals was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant assay (FRAP), N, N-dimethyl-p-phenylendiamine (DMPD) and nitric oxide (NO) scavenging assays. Experimental results indicated that jackfruit wine was effective in DPPH radical scavenging (69.44 ± 0.34%), FRAP (0.358 optical density value, O.D.), DMPD (78.45 ± 0.05%) and NO (62.46 ± 0.45%) capacity. By the analysis of the high performance liquid chromatography coupled to diode array detector (HPLC-DAD), two phenolic compounds namely gallic acid and protocatechuic acid were identified. The jackfruit wine was also able to protect H2O2 + UV radiation and γ-radiation (100 Gy) induced DNA damage in pBR322 plasmid DNA. The antioxidant and DNA damage protecting properties of jackfruit wine confirmed health benefits when consumed and could become a valuable source of antioxidant rich neutraceuticals. Additionally, the wine could be a commercially valuable by-product for the jackfruit growers.  相似文献   

17.
Sweet sorghum (Sorghum bicolor (L.) Moench.) is a drought-tolerant crop with high resistance to saline-alkaline soils, and sweet sorghum may serve as an alternative summer crop for biofuel production in areas where irrigation water is limited. A two-year study was conducted in Northern Greece to assess the productivity (biomass, juice, total sugar and theoretical ethanol yields) of four sweet sorghum cultivars (Sugar graze, M-81E, Urja and Topper-76-6), one grain sorghum cultivar (KN-300) and one grass sorghum cultivar (Susu) grown in intermediate (3.2 dS m−1) or in high (6.9 dS m−1) soil salinity with either low (120 mm) or intermediate (210 mm) irrigation water supply (supplemented with 142–261 mm of rainfall during growth). The soil salinity and irrigation water supply effects on the sorghum chlorophyll content index, photosystem II quantum yield, stomatal conductance and leaf K/Na ratio were also determined. The sorghum emergence averaged 75,083 plants ha−1 and 59,917 plants ha−1 in a soil salinity of 3.2 dS m−1 and 6.9 dS m−1, respectively. The most affected cultivar, as averaged across the two soil salinity levels, was the Susu grass sorghum emerging at 53,250 plants ha−1, followed by the Topper-76-6 sweet sorghum emerging at 61,250 plants ha−1. The leaf K/Na ratio decreased with decreasing irrigation water supply, in most cases, but it was not significantly affected by soil salinity. The dry biomass, juice and total sugar yields of sorghum that received 210 mm of irrigation water was 49–88% greater than the yields of sorghum that received the 120 mm of irrigation water. Sorghum plants grown in a soil salinity of 3.2 dS m−1 produced 42–58% greater dry biomass, juice and total sugar yields than the yields of sorghum plants grown in a soil salinity of 6.9 dS m−1. The greatest theoretical ethanol yield was produced by sweet sorghum plants grown in a soil salinity of 3.2 dS m−1 with 210 mm of irrigation water (6130 L ha−1, as averaged across cultivar), and the Urja and Sugar graze cultivars produced the most ethanol (7620 L ha−1 and 6528 L ha−1, respectively). Conclusively, sweet sorghum provided sufficient juice, total sugar and ethanol yields in fields with a soil salinity of 3.2 dS m−1, even if the plants received 50–75% of the irrigation water typically applied to sorghum.  相似文献   

18.
The study deals with evaluation of antifungal and antiaflatoxigenic Caesulia axillaris Roxb. essential oil (EO) against herbal raw materials deteriorating fungi and its free radical scavenging activity. During mycoflora analysis these herbal raw materials were found to be severely contaminated by different fungi and aflatoxins. A total of nine different fungal species were isolated from three herbal raw materials. Aspergillus flavus LHPtc was recorded as the highest aflatoxin B1 producing strain. EOs of some plants were tested for their fungitoxicity against the toxigenic strain A. flavus LHPtc, and C. axillaris EO was found as potent fungitoxicant. C. axillaris EO was chemically characterized through GC-MS analysis which depicted the presence of 18 compounds, dl-limonene and Euasarone being the major components. The EO exhibited broad spectrum of fungitoxicity against fungi causing postharvest deterioration of herbal raw materials. At 1.0 μl ml−1 the oil showed complete inhibition of fungal growth and aflatoxin B1 production was inhibited at 0.8 μl ml−1. Free radical scavenging activity of the oil was also recorded by 2,2-diphenyl-1-picrylhydrazyl assay, and its IC50 value was found 18 μl ml−1. The safety limit of the EO was determined in terms of LD50 on mice, which was 9166.6 μl kg−1, suggesting its non mammalian toxicity. The EO of C. axillaris may be recommended as a plant based preservative in enhancement of shelf life of herbal raw materials by preventing their lipid peroxidation as well as biodeterioration due to fungal and aflatoxin contamination.  相似文献   

19.
Black currant polyphenols: Their storage stability and microencapsulation   总被引:1,自引:0,他引:1  
Interest in the consumption of fresh fruits is, to a large extent, due to its content of bioactive nutrients and their importance as dietary antioxidants. There is a growing demand for delivery of antioxidants through functional foods with the related challenge of protecting their bioactivity during food processing and subsequent passage through the gastrointestinal tract. This study focuses on the evaluation of concentration of bioactive compounds in black currant berries (Ribes nigrum L.) and retention of black currant polyphenol compounds and their antioxidant activity after microencapsulation by spray-drying. The polyphenol contents and antioxidant activities were assessed for 5 black currant cultivars grown in Canada in fresh and stored fruits at −20 °C for 9 months. The Ben Alder cultivar was the richest in anthocyanins and flavonols content with high antioxidant potential measured with ABTS and DPPH radicals (4.5 and 2.4 mM/100 g). Black currant polyphenols were stable during 9 month of storage at −20 °C. The results of this study indicated that in black currants storage did not affect negatively the antioxidant capacity. The good stability of bioactive compounds of black currants during freezer storage allows prolonging the storage time of these berries. Maltodextrins with different DE (dextrose equivalent): DE11, DE18, DE21 and inulin were selected as wall material. The stability of encapsulated polyphenols during 12 months storage at 8 °C and 25 °C was evaluated. Compared to maltodextrins DE18 and DE21, maltodextrin DE11 had not only higher drying yield but also offered better protection for phenolics during storage. Radical scavenging activity studies demonstrated significant antioxidant activity of microencapsulated powders before and after storage. The black currant polyphenol microcapsules described in this study represent a promising food additive for incorporation into functional foods due to antioxidant content.  相似文献   

20.
Requirements of consumers for products with low residues of pesticides have increased the need for alternative disease management practices. The concentration of boron in fruit affects its quality, shelf life and the development of physiological disorders. However, the effect of boron on the susceptibility of peach to fruit rots has not been reported. This study investigated the effect of boron (Power B and Borax) on the development of Monilinia laxa on peaches (cv Andross). Mycelial growth of M. laxa was inhibited on potato dextrose agar supplemented with 750 μg ml−1 of Borax or 1000 μg ml−1 of Power B. The EC 50 values were 107.9 and 522.4 for Borax and Power B respectively. Field investigations showed that the incidence of peach infections by M. laxa was negatively correlated with the content of Boron in the leaves. Post-harvest dipping of peaches in Power B or Borax solution, at concentrations recommended by manufacturer (2 μg ml−1 for Power B and 1 mg ml−1 for Borax), significantly reduced the development of M. laxa. Power B, at rates of 6 μg ml−1, and Borax at rates of 3 mg ml−1 were the most effective in reducing infections by M. laxa. Finally, post-harvest dipping of fruit in Power B or Borax reduced losses of fruit weight and improved fruit firmness one month after storage, showing that boron increased the maintainability of peaches in cold storage. Peaches treated with 6 μg ml−1 Power B or 3 mg ml−1 Borax had the highest flesh firmness and the lowest water losses, while untreated control peaches were the least firm. Generally, Borax was significantly less effective than Power B, but better than the control treatment.  相似文献   

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