Evaluation of the bioactive compounds and the antioxidant capacity of grape pomace

Grape pomace is an agro‐industrial residue produced worldwide and mainly employed for animal feed or as a fertiliser. Several studies have shown that grape pomace is a rich source of bioactive compounds, such as phenolic compounds, polysaccharides, fatty acids and others. Three varieties of grape pomace were evaluated in this study. Antioxidant activity was determined by three different methods, namely, DPPH˙, ABTS and ferrous ion assays. Fatty acids and phenolic compounds were identified, respectively, by gas and liquid chromatography. Results showed that grape pomace is a rich source of polyunsaturated fatty acids and phenolic compounds. Cabernet Sauvignon pomace revealed higher values of total phenolic compounds, total flavonoids and total monomeric anthocyanin, and presented the lowest value of EC₅₀, and thus a higher antioxidant activity among the samples analysed.     

Quality analysis of ‘Redhaven’ peach fruit grafted on 11 rootstocks of different genetic origin in a replant soil

The fruit quality of ‘Redhaven’ peach [Prunus persica (L.) Basch.] grafted on 11 (Adesoto, Julior, GF 677, Monegro, Barrier 1, Cadaman, MrS 2/5, Ishtara, Penta, Tetra and peach seedling) experimental rootstocks was evaluated in 2008 under replant orchard conditions. Several quality indices [weight, flesh firmness (FF), ground colour measurements, and soluble solids content (SSC)] were measured, and HPLC analysis were performed for numerous chemical parameters (quantification of individual sugars, organic acids, phenolic compounds in skin and in pulp). Total phenolic content and antioxidant capacity in skin and in pulp were also measured. Julior had the heaviest fruit, while Barrier 1 and GF 677 produced fruit lighter in weight. Rootstocks influenced harvest maturity. Monegro produced the least ripe fruit, characterised by high FF, phenolic compounds in the skin and low SSC. Adesoto rootstock resulted in the best overall fruit quality (high values of SSC, individual and total sugar content levels, individual and total organic acids and phenolic compounds in pulp) as well as high total yield. Julior rootstock also produced good quality peach (high values of SSC, individual and total sugars). Cadaman and peach seedling rootstock produced ‘Redhaven’ fruit of the lowest quality, indicated by low values of sugars, organic acids, phenolic compounds in pulp and in skin.     

Natural Antioxidants in Purple Sprouting Broccoli under Mediterranean Climate

Abstract: Broccoli, (Brassica oleracea var. Italica), is generally recognized as a nutritive food rich in natural antioxidants, including vitamins and phenolics compounds. Phytochemical composition of 3 different purple sprouting broccoli varieties according with their production cycle: EEP (Extra Early), EP (Early), and LP (Late) were determined. The 3 cultivars tested were grown under the same conditions in an experimental field (SE Spain) where they were not previously cultivated since these cultivars are typical of cold, Northern‐European areas. EP variety showed greater growth according to the photosynthetic rate and C assimilation. However, it was not possible to obtain inflorescences for variety LP. The health‐promoting compounds (vitamin C, phenolic compounds, and glucosinolates) were higher in purple broccolis than in traditionally grown green broccolis and showed differences according to the variety. With respect to the use of broccoli byproducts as source of antioxidants, any variety would be suitable although the leaves of EP variety seems the richest in total phenolic acids, whereas the amount of anthocyanins was higher in LP variety, followed by EP and EEP varieties. Under our experimental conditions, the levels of glucosinolates were higher in purple broccoli than in green cultivars and also higher than other purple broccolis grown under different climate conditions. Therefore, the results reported data for production of the EEP and EP varieties in the Mediterranean climate with potential to obtain vegetables with improved nutritional quality. Practical Application: The results of this study reported data of the health‐promoting nutrients and natural antioxidants of EEP, EP, and LP purple sprouting broccoli varieties grown under the Mediterranean climate. The vitamin C, phenolic compounds, and glucosinolates in these purple varieties were higher than in traditionally grown green broccolis and other purple broccolis grown under different climate conditions.     

Analysis of non-coloured phenolics in port wines by capillary zone electrophoresis Influence of grape variety and ageing

 Different experimental varietal port wines were analysed in order to determine differences in the concentrations of phenolic compounds between some commonly used grapes varieties (Touriga Francesa, Touriga Nacional, Tinta Roriz and Tinta Barroca). Although all samples had the same qualitative pattern of non-coloured phenolic compounds, Touriga varieties contained more than twice the concentration of these compounds compared to the Tinta varieties. A preliminary study of the effect of ageing on these compounds revealed an overall increase in those components associated with the bitter or astringent characteristics of food and beverages (tyrosol, gallic acid and catechin). Received: 1 August 1997     

Analysis of non-coloured phenolics in port wines by capillary zone electrophoresis Influence of grape variety and ageing

 Different experimental varietal port wines were analysed in order to determine differences in the concentrations of phenolic compounds between some commonly used grapes varieties (Touriga Francesa, Touriga Nacional, Tinta Roriz and Tinta Barroca). Although all samples had the same qualitative pattern of non-coloured phenolic compounds, Touriga varieties contained more than twice the concentration of these compounds compared to the Tinta varieties. A preliminary study of the effect of ageing on these compounds revealed an overall increase in those components associated with the bitter or astringent characteristics of food and beverages (tyrosol, gallic acid and catechin). Received: 1 August 1997     

利用多酚/蛋白互作模型研究多酚对葡萄酒涩感的影响

研究不同红葡萄酒中不同聚合度的酚类物质与蛋白质相互作用的差异性,找出影响涩感的关键成分,为葡萄酒酿造工艺的改良及葡萄品种的选育提供理论依据。以不同品种的红葡萄酒为材料,利用C18固相萃取柱将葡萄酒的酚类物质分离为单体酚、低聚物、高聚物三部分,测定其总酚、总黄烷醇含量,采用SDS-PAGE及荧光光谱法研究不同酚类物质与蛋白质的相互作用。测得红葡萄酒的总酚和总黄烷醇含量存在显著差异,红葡萄酒中不同组分的总酚和总黄烷醇含量表现为:单体酚低聚物高聚物。SDS-PAGE及荧光光谱实验的结果显示高聚物对蛋白质的影响较强,单体酚与低聚物则因酒而异。葡萄酒中不同聚合度的成分对涩感的影响不同。因此,在葡萄品种选择和葡萄酒酿造工艺改良的过程中可以根据目标而进行酚类物质的控制,特别是高聚物的调控。     

Characterisation of polyphenols and antioxidant properties of five lettuce varieties and escarole

Salad vegetables could be relevant as dietary sources of natural antioxidants. A better knowledge of their composition can be useful for understanding their potential bioavailability and biological activities. The antioxidant compounds, polyphenols and vitamin C, have been determined in five varieties of lettuce (iceberg, romaine, continental, red oak leaf, lollo rosso) and one variety of escarole (frissé). The polyphenol study by HPLC-DAD-MS/MS ESI allowed the identification of two compounds previously not reported in lettuce; quercetin and luteolin rhamnosyl-hexosides. Qualitative and quantitative differences were observed between the polyphenol profiles. Caffeic acid derivatives were the main phenolics in green varieties, while flavonols were detected in higher quantities in red varieties and escarole, and anthocyanins were only present in red-leafed varieties. The highest total phenolic content was observed in red-leafed varieties while the highest level of vitamin C was detected in the continental variety. The red varieties showed the highest antioxidant activity by all the methods assayed.     

温州蜜柑、椪柑采后酚类物质及抗氧化活性比较研究

通过研究温州蜜蜂柑、椪柑两个常见柑橘品种贮藏期间类黄酮、酚酸类物质及抗氧化活性的变化规律,评价其采后的营养品质。结果表明：贮藏60d后温州蜜柑较好地保持了抗坏血酸含量,而椪柑损失较大。类黄酮类物质较稳定,温州蜜柑中黄烷酮含量贮藏后有所增加,椪柑中则呈缓慢下降趋势,2种柑橘中酚酸类物质贮藏后都有所增加。总酚含量在贮藏前期呈下降趋势,贮藏后期温州蜜柑中总酚含量增加而在椪柑中进一步下降。抗氧化能力与抗坏血酸的变化趋势类似。与椪柑相比,贮藏期间温州蜜柑能更好地保持果实的营养品质及酚类物质,从而保持较高的抗氧化活性。     

High performance liquid chromatographic analysis of phenolic compounds and their antioxidant activities in rice varieties

The analytical method for the determination of phenolic compounds in rice varieties was developed. The method consisted of extraction of phenolic compounds from rice before analysis by high performance liquid chromatography (HPLC). Reversed phase HPLC equipped with photodiode array detection was used and the separation condition was optimized. Under the optimum condition, twelve phenolic compounds were separated within 24 min. Pressurized liquid extraction (PLE) was used to extract free phenolic compounds from rice with the optimum extraction condition of 70% methanol and extraction time of 15 min. While, bound phenolic compounds were extracted using alkaline hydrolysis for 15 min. Six varieties of Thai rice including pigment and non-pigment rice in their brown and polished forms were investigated. All of 12 phenolic compounds were detected as free phenolic compounds in all samples. Ferulic acid was the most abundant free phenolic compounds in all samples, while ferulic acid and p-coumaric acid were found as bound phenolic compounds in some samples. The content of phenolic compounds, total flavonoid and antioxidant activity detected in pigment rice and brown form were higher than non-pigment rice and polished form.     

Selecting new peach and plum genotypes rich in phenolic compounds and enhanced functional properties

Fourteen red-fleshed plum (Prunus salicina Erhr. and hybrids) and eight peach [Prunus persica (Batsch) L.] genotypes were characterized for their total phenolic and anthocyanin contents. Selected rich phenolic genotypes showed high antioxidant activity, stable colour properties and good antimicrobial activity. Results indicated positive correlations between phenolic compounds (r² = 0.83) and antioxidant activity for both types of fruit. Colorants prepared from an anthocyanin rich plum genotype showed similar hue to that of synthetic colorant FD&C red 3 and higher stability than a commercial red grape colorant with respect to time, temperature and pH. Additionally, a selected rich phenolic plum genotype exhibited strong antimicrobial activity against Salmonella Enteritidis and Escherichia coli O157:H7. This study proposes that selection of crops high in phenolic compounds can be related to enhanced functional properties and opens the possibility of breeding fruits with targeted functional properties for the fresh produce and processing market.     

Optimization of extraction conditions of total phenolics, antioxidant activities, and anthocyanin of oregano, thyme, terebinth, and pomegranate

The purpose of this study was to evaluate the total phenolic extracts and antioxidant activity and anthocyanins of varieties of the investigated plants. These plants include oregano, thyme, terebinth, and pomegranate. The optimum extraction conditions including temperature and solvent of the extraction process itself were investigated. Total phenolic and anthocyanin extracts were examined according to Folin-Ciocalteu assay and Rabino and Mancinelli method, respectively. The effect of different extracting solvents and temperatures on extracts of phenolic compounds and anthocyanins were studied. Plant samples were evaluated for their antioxidant chemical activity by 2, 2-diphenyl-1-picrylhydrazl assay, to determine their potential as a source of natural antioxidant. Results showed that all tested plants exhibited appreciable amounts of phenolic compounds. The methanolic extract (60 °C) of sour pomegranate peel contained the highest phenolic extract (4952.4 mg/100 g of dry weight). Terebinth green seed had the lowest phenolic extract (599.4 mg/100 g of dry weight). Anthocyanins ranged between 3.5 (terebinth red seed) and 0.2 mg/100 g of dry material (thyme). Significant effect of different extracting solvents and temperatures on total phenolics and anthocyanin extracts were found. The methanol and 60 °C of extraction conditions found to be the best for extracting phenolic compounds. The distilled water and 60 °C extraction conditions found to be the best for extracting anthocyanin.     

蓝莓果实多酚和抗氧化研究

利用LC-MS结合标准品对贵州麻江栽培的杰兔、园蓝、奥尼尔、夏普兰、海岸、蓝雨6个品种蓝莓成熟果实酚类物质进行定性分析。利用HPLC定量分析其15种单体花色苷、3种酚酸、3种类黄酮物质含量,利用分光光度计分析其总酚、总花青素、DPPH抗氧化能力。结果表明:6个品种蓝莓成熟果实总花青素、总酚、21种单体酚类物质含量、DPPH抗氧化能力、果实直径和质量差异较大,其中园蓝的总酚、总花青素、10种花色苷和绿原酸含量相对最高,园蓝和蓝雨具有较高的总酚、总花色苷含量,但是其果实直径和质量较小,适宜加工或提取活性成分。     

Discrimination of Tsingtaodahua from Other Hop Cultivars and Its Quality Control by Molecular Analysis

Random amplified polymorphic DNA (RAPD) was used for hop varietal identification, primarily to distinguish Tsingtaodahua, a fine Chinese variety. Eleven typical varieties, including four aroma hops, five bitter hops, Tsingtaodahua and Cluster, were successfully identified on the basis of 28 polymorphic RAPD bands amplified by five random primers. UPGMA analysis of RAPD data showed genetic relationship among analyzed varieties consistent with traditional hop classification. Subsequently, one specific RAPD fragment was converted to a sequence tagged site (STS) marker which can detect as little as a 5% admixture of the variety Kirin 1 in Tsingtaodahua. The RAPD and STS markers can be successfully used for Tsingtaodahua identification and quality control.     

Influence of taro (Colocasia esculenta L. Shott) growth conditions on the phenolic composition and biological properties

Colocasia esculenta (L.) Shott, commonly known as taro, is an essential food for millions of people. The leaves are consumed in sauces, purees, stews, and soups, being also used in wound healing treatment. Nowadays, the consumers’ demand for bioactive compounds from the diet led to the development of new agricultural strategies for the production of health-promoting constituents in vegetables. In this work, two strategies (variety choice and irrigation conditions) were considered in the cultivation of C. esculenta. The effect on the phenolic composition of the leaves was evaluated. Furthermore, a correlation between the biological activity of the different varieties and their chemical composition was established. Qualitative and quantitative differences in the phenolic composition were observed between varieties; furthermore, the irrigation conditions also influenced the composition. C. esculenta varieties were able to scavenge several oxidant species and to inhibit hyaluronidase, but data suggest that metabolites other than phenolics are involved. The results show that cultivation strategies can effectively modulate the accumulation of these types of bioactive compounds. Furthermore C. esculenta wound healing potential can be attributed, at least in part, to the protection of the wound site against oxidative/nitrosative damage and prevention of hyaluronic acid degradation.     

EFFECTS OF VARIETY AND GROWTH SEASON ON THE ORGANOLEPTIC AND NUTRITIONAL QUALITY OF HYDROPONICALLY GROWN TOMATO

The effects of variety and season on several organoleptic and nutritional quality parameters (i.e., dry weight (dw), total sugars, soluble solid compounds, titratable acidity (TA), electrical conductivity (EC), juiciness, firmness, vitamin C (vit C), total phenolic compounds, hydrophilic antioxidant capacity and minerals) of five different varieties of tomatoes (i.e., Jack, Cabrales, Jaguar, Iker and Nevada) grown in two crop cycles (spring and autumn) were studied. Each variety presented its own specific characteristics regarding the chosen parameters. Firmness, TA and EC were season dependent, whereas soluble solids content did not change between cycles. In some varieties, the dw, juiciness and total sugars were affected by climatic conditions. The total phenolic compounds and the hydrophilic antioxidant capacity were variety dependent in both cycles. By contrast, the vit C content was variety dependent only in the autumn cycle. Similarly, these latter parameters (phenolic compounds, hydrophilic antioxidant capacity and vit C) were also season dependent, showing higher values in the spring than in the autumn cycle. The effect of tomato variety and season on mineral contents is also discussed. Those tomatoes grown in the spring cycle had better quality according to the organoleptic parameters studied here as well as to a higher antioxidant capacity. The percentages of the recommended dietary allowances supplied by the studied tomatoes were not significantly affected by variety or season, despite differences in their physicochemical compositions.     

Characterization of Water Extractable Crude Polysaccharides from Cherry,Raspberry, and Ginseng Berry Fruits: Chemical Composition and Bioactivity

Water extractable crude polysaccharides from three sweet cherry varieties, raspberries, and ginseng berry pulp were evaluated for their chemical composition, structural features, molecular weight, and bioactive properties. The yields of the crude polysaccharides isolated from cherries, raspberries, and ginseng berry pulp ranged from 0.79 to 0.18% on a dry weight fruit basis. All of the crude polysaccharides contained protein, phenolic compounds, and uronic acid. Each crude polysaccharide contained the sugar monomers: rhamnose, arabinose, xylose, mannose, galactose, and glucose. Of the water extractable polysaccharides obtained from the mature fruits, the crude polysaccharides from the raspberries had the highest molecular weight while the crude polysaccharides from the ginseng berry pulp had the smallest molecular weight. Results from Fourier transform infrared spectroscopy suggested that the crude polysaccharides contained a monosaccharide with six carbon atoms in a D-glucopyranose ring and a protein component. The crude polysaccharides from cherries, raspberries, and ginseng berry pulp were shown to possess antioxidant activity as determined with the ferric reducing antioxidant power and the 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays. The effect of crude polysaccharides on: (1) caspase 3 activation, which was determined using a hypoxia/reoxygenation model, and (2) immunostimulation, which was determined by evaluating the inflammatory mediator response, were examined. Only crude polysaccharides obtained from certain varieties of sweet cherries inhibited caspase 3 activation in a dose-dependent manner, while only the crude polysaccharides obtained from ginseng berry pulp stimulated immune function. Crude polysaccharides present in small fruits do possess bioactivities that may enhance human health.     

Impact of thermoplastic extrusion process on chemical,nutritional, technological and sensory properties of gluten-free breakfast cereals from pigmented rice

The black rice and red rice varieties cultivated in Brazil are rich in dietary fibres, proteins, and phenolic compounds with great antioxidant potential, being a promising alternative for the production of healthy gluten-free snacks. In this study, pigmented rice flours and their respective extrudates were characterised for the nutrient profile, phenolic compounds, antioxidant capacity, technological properties and colour aspects, and the results were compared through heat map analysis. Black rice snacks presented better nutrient and phenolic profiles, while the red rice snacks stood out for the expansion and texture properties. Both breakfast cereals were nutritive, gluten-free, hypoallergenic, naturally coloured (no need to add artificial colorants) and presented good sensory acceptance, with the higher scores for the attributes shape, size, colour and crispness.     

Phenolic Composition,Essential Oil,and Antioxidant Activity in the Aerial Part of Artemisia Herba-Alba from Several Provenances: A Comparative Study

This study characterized the phenolic, aroma compositions, and antioxidant capacities of four Artemisia herba alba accessions collected from north and center regions in Tunisia in order to select valuable origin with optimal bioactive compounds production. The total polyphenol and flavonoid contents varied between accessions with maxima contents observed in center regions. Kaempherol, apigenin, naringenin, p-coumaric, trans-cinnamic, and caffeic acids were the most abundant compounds with percentage varying depending on the considered accession. Significant changes on essential oil yields (0.4–1.2%) were found between accessions and three different oil chemotypes were distinguished: camphor, fenchol/α-thujone, and α-thujone/camphor. Cluster analysis of volatile and phenolic compositions grouped the accessions on different groups. Antioxidant activities of extracts were found to be higher than essential oils for the four provenances. The results suggested that the center regions have high potential for selecting varieties rich on essential oil, antioxidant phenolic acids, and flavonoids.     

High temperature-tolerant tomato lines: bioactive compounds

High global temperatures will be a great challenge for agricultural production in the near future. Therefore, adaptation of agricultural crops to the high temperatures or development of new heat-tolerant crops with known bioactive compounds is an important strategy for nutritional health and crop improvement programs. In this context, the bioactive compounds of newly developed high temperature-tolerant tomato lines were investigated in terms of lycopene, β-carotene, ascorbic acid and phenolic compounds to assist breeders for the selection of high temperature tolerant tomato varieties with high nutritional quality. Nineteen tomato lines, including control varieties from the “Turkey F1 Hybrid vegetable variety and quality line development” project and the GAP Agricultural Research Institute, were selected for the investigation. Line 11 was superior in lycopene and β-carotene content, while line 18 was superior in ascorbic acid content as compared to control varieties Cansun F1 and Alsancak RN F1. Urfa 2012 and line 28 were found to have the highest numbers of phenolic compounds. Chlorogenic acid, naringenin, trans-ferulic acid and rutin were key phenolic compounds detected in each of the tomato lines. These newly released tomato lines can be used as value-added germplasm or parent sources to develop new heat-tolerant cultivars in breeding programs or as commercial cultivars for their superior functional qualities.