Relationships between seed and berry development of Vitis Vinifera L. cv Shiraz: Developmental changes in seed morphology and phenolic composition

Berries were collected regularly from fruit set to berry maturity from irrigated (Shiraz) grapevines in a Barossa valley vineyard. Seeds were removed for detailed study of physical attributes (weight, moisture, colour) and phenolic composition (seed tannins). Three phases of seed growth and development were discerned: (1) a phase of seed growth characterised by a steady increase in both fresh weight and dry weight, biosynthesis and accumulation of flavan‐3‐ols and tannins, and green appearance; (2) a transition phase where seed fresh weight and dry weight reached a maximum, but with continuing enlargement of the basal end. Accumulation of flavan‐3‐ols and seed tannins also reached a maximum during phase 2, and was accompanied by an onset of tannin oxidation, and yellow appearance; and finally, (3) a phase of seed drying and maturation defined by a decrease in fresh weight due to water export, a sustained oxidation of tannins, and overall brown appearance. These phases in seed development correspond to particular stages in berry development. Seeds reached maximum fresh seed weight and full size at the beginning of berry colouring (veraison), while maximum dry seed weight coincided with maximum berry weight. Changes in seed phenolics were linked to berry development and maturation. Changes in seed coat colour were also related to developmental changes in berry anthocyanins and total skin phenolics, indicating that the external appearance and colour of the seed coat may be used as an additional indicator of overall berry ripeness. A graduated colour chart was developed to provide an objective index of seed coat colour and thus developmental status of seeds and berry.     

The extraction of passion fruit oil with green solvents

In the present paper, the extraction of passion fruit oil with acetone, ethanol and isopropanol of passion fruit seeds under three different techniques (ultrasound, shaker and soxhlet) were studied. The influence of seed to solvent ratio, time and type of solvent were investigated during ultrasound, shaker and soxhlet process. Hexane was used as well, as an extraction solvent to evaluate the extraction of oil in all extraction process studied to make a comparison among the employed solvents. The temperature was kept isoterminally at 40 °C in both shaker and ultrasound process. The highest yield when green solvents were was 23.8%, during ultrasound process, with acetone was used. Our results indicate that ultrasound can greatly replace the conventional extraction.     

Analysis of tannins in seeds and skins of Shiraz grapes throughout berry development

The flavan-3-ol and proanthocyanidin composition of both seeds and skin of Vitis vinifera L. cv. Shiraz grapes was determined by reversed-phase HPLC after acetone extraction and acid-catalysis in the presence of excess phloroglucinol. Samples were taken at weekly intervals from fruit-set until commercial harvest. The main period of proanthocyanidin accumulation in grape seeds occurred immediately after fruit-set with maximum levels observed around veraison. Over two seasons there was variation in both the timing and content of proanthocyanidins in seeds. In skin, proanthocyanidin accumulation occurred from fruit set until 1–2 weeks after veraison. Proanthocyanidin subunit composition was different in seeds and skin and changed during berry development but the mean degree of polymerisation of the tannin polymers in skins was higher than in the seeds at all stages of berry development. Proanthocyanidin levels in both seeds and skin decreased between veraison and harvest. Additional proanthocyanidin subunits were released when the residues remaining after acetone extraction were subjected to direct acid-catalysis in the presence of phloroglucinol. In the seeds, these accounted for much of the post-veraison decrease, but not in grape skin. At harvest, 75% of extractable berry proanthocyanidin was in the seeds. Accumulation of proanthocyanidins in the seeds appears to be independent of that in the skins, but in both tissues synthesis occurs early in berry development and maximum levels are reached around veraison.     

Influence of ripening stage and maceration length on the contribution of grape skins,seeds and stems to phenolic composition and astringency in wine-simulated macerations

This paper studies the influence of ripening stage and maceration time (1–23 days) on the contribution of each cluster grape components to phenolic composition and astringency in wine-simulated macerations. In general terms, proanthocyanidin extraction from skins, stems and especially from seeds increased with maceration time. The ripening stage also had a major influence on tannin extraction and astringency. The tannin contribution from skins and stems increased with ripening but the contribution from the seeds decreased. The contribution to astringency from all cluster components was clearly higher when the grapes were unripened. The mean degree of polymerization of the tannins from skin and seed components was unaffected by ripening and maceration length.     

Growth and Compositional Changes During the Various Developmental Stages of Some Saudi Arabian Date Cultivars

Compositional changes during fruit maturation were studied in two important date cultivars grown in Saudi Arabia. Physical analyses showed that the fruit weight, length, diameter and weight of seed were highest at the mature color stage. Chemical analyses including moisture, total nitrogen, fat, fiber, ash, tannins, vitamin C, β-carotene, and 10 nutritionally essential minerals showed that all were highest at the early stages of development and decreased during maturation. Reducing sugars were dominant in both cultivars and showed progressive increase during ripening with fructose and glucose as the only detected constituents. Sucrose content reached its maximum in both cultivars at the mature color stage then dropped sharply at the ripe stage. The total sugar content in both cultivars tended to increase all throughout maturation.     

Extraction of condensed tannins from beach pea (Lathyrus maritimus L.) as affected by different solvents

The condensed tannins of beach pea, green pea and grass pea were extracted using methanol or acetone at different concentrations with or without acidification. Among solvents tested, 70% acetone, containing 1% concentrated HCl, extracted a maximum amount of condensed tannins from beach pea, green pea and grass pea. Condensed tannins extracted were assayed using a 0.5% vanillin solution in methanol containing 4% HCl (v/v). Beach pea contained a higher amount of condensed tannins (11.6 g/100 g) than Indian grass pea (1.54 g/100 g), Canadian grass pea (109 mg/100 g) or green pea (72.0 mg/100 g). The fresh green seeds and pod shells of beach pea had lower amounts of tannins (7.19 and 9.13 g/100 g, respectively) than mature seeds and pod shells (11.7 and 2.05 g/100 g, respectively). Branches plus stems of beach pea contained the lowest amount of condensed tannins (0.95 g/100 g) as compared to all other parts of the plant.     

生姜风味物质的提取和成分分析

采用GC-MS方法分析了水蒸气蒸馏法提取的姜精油化学成分，共分析鉴定出49种化学成分；同时用3种不同的有机溶剂（丙酮、100％乙醇、80％乙醇）萃取干姜得到姜油树脂。利用HPLC-MS方法检测了3种姜油树脂的化学成分。丙酮萃取法姜油树脂得率最高，辛辣呈味成分也最为丰富，而80％乙醇溶剂浸提的产品中，姜油树脂的主要呈味成分-姜醇的相对含量最高.     

龙眼核多酚提取工艺的正交试验优化及其分离纯化与结构表征

采用正交试验设计优化龙眼核多酚的提取条件。在单因素试验的基础上,以乙醇体积分数、料液比、提取时间、提取温度为自变量,以龙眼核多酚提取量为考察指标,经过四因素三水平正交试验得出龙眼核多酚提取的最佳工艺条件：乙醇体积分数40%、料液比1∶20（g/mL）、提取温度70 ℃、提取时间90 min。在该条件下龙眼核多酚提取量为36.15 mg/g。通过对4 种树脂静态吸附及解吸性能的比较,确定D3520型树脂为龙眼核多酚分离纯化的理想树脂,洗脱剂乙醇体积分数为40%时,树脂对多酚的解吸率最高。采用傅里叶变换离子回旋共振质谱（Fouriertransform ion cyclotron resonance mass spectrometry,FT-ICR-MS）对龙眼核多酚结构进行初步分析,结果表明,龙眼核多酚主要成分为以鞣花酸及其衍生物为主的小分子质量水解单宁。通过核磁共振、紫外光谱和红外光谱对FT-ICR-MS中2 种丰度很高的物质进行分析,确定其分别为鞣花酸和(S)-flavogallonic acid,后者为鞣花酸的衍生物。     

麻栎橡子单宁脱除工艺优化及抗氧化性

为探索高效可行的麻栎橡子单宁脱除工艺,实现其综合开发,以桥山林区麻栎橡子为原料,采用超声辅助乙醇法对影响单宁脱除率的因素进行单因素试验,选择影响显著的4个因素进行响应面分析,并测定单宁对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和羟自由基(·OH)的清除率,以探索麻栎橡子单宁的抗氧化活性。结果表明,液料比、乙醇体积分数、脱除温度、超声功率对单宁脱除率影响显著,模型拟合效果显著。最优脱除工艺为液料比42∶1(mL/g)、乙醇体积分数53%、脱除温度65℃、超声功率240 W,单宁脱除率为37.27%。麻栎橡子单宁抗氧化性与其质量浓度呈线性正相关,质量浓度为80 mg/L时,其对DPPH自由基的清除率可达75.56%,对·OH的清除率可达62.74%,可作为新型抗氧化剂。     

Microwave-assisted extraction and anti-oxidation activity of polyphenols from lotus (Nelumbo nucifera Gaertn.) seeds

Lotus seeds polyphenols have not been studied at the anti-oxidation activity in oil and the extraction by now. Microwave-assisted extraction was employed to extract polyphenols from lotus seeds, which is a process that uses microwave energy and solvents to extract target compounds from various matrices. Orthogonal analysis methodology was used to determine the optimal extraction conditions for microwave power, ethanol concentration, extraction time, and solid-liquid ratio which were 300 W, 90%, 35 s, and 1:10, respectively. Ethanol concentration is the most significant factor influencing on the yield of lotus seed polyphenols. Antioxidant trials using oil have shown lotus seed polyphenols can effectively inhibit the production of the peroxide and anisidine in oil to a certain extent, and these polyphenols have strong anti-oxidation activity. From anti-oxidation synergistic effect on oils with the lotus seed polyphenols and other antioxidants, vitamin C shows the strongest synergy.     

Reutilization of mango byproducts: study of the effect of extraction solvent and temperature on their antioxidant properties

Mango biowastes, obtained after processing, contain large amounts of compounds with antioxidant activity that can be reused to reduce their environmental impact. The present study evaluates the effect of solvent (methanol, ethanol, acetone, water, methanol:water [1:1], ethanol:water [1:1], and acetone:water [1:1]), and temperature (25, 50, and 75 °C) on the efficiency of the extraction of antioxidants from mango peel and seed. Among the factors optimized, extraction solvent was the most important. The solvents that best obtained extracts with high antioxidant capacity were methanol, methanol:water, ethanol:water, and acetone:water (β-carotene test, antioxidant activity coefficient 173 to 926; thiobarbituric acid reactive substances test, inhibition ratio 15% to 89%; 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid ABTS(·+); and 2,2-diphenyl-1-picrylhydrazyl DPPH· scavenging, 7 to 22 and 8 to 28 g trolox equivalent antioxidant capacity [TE] per 100 g mango biowaste on a dry matter basis [DW]). Similarly, the flavonoid (0.21 to 1.4 g (+)-catechin equivalents per 100 g DW), tannin (3.8 to 14 g tannic acid equivalents per 100 g DW), and proanthocyanidin (0.23 to 7.8 g leucoanthocyanidin equivalents per 100 g DW) content was highest in the peel extracts obtained with methanol, ethanol:water, or acetone:water and in the seed extracts obtained with methanol or acetone:water. From the perspective of food security, it is advisable to choose ethanol (which also has a notable antioxidant content), ethanol:water, or acetone:water, as they are all solvents that can be used in compliance with good manufacturing practice. In general, increasing temperature improves the capacity of the extracts obtained from mango peel and seed to inhibit lipid peroxidation; however, its effect on the extraction of phytochemical compounds or on the capacity of the extracts to scavenge free radicals was negligible in comparison to that of the solvent. PRACTICAL APPLICATION: There are many antioxidant compounds in mango peel and seed, and they could be used as a natural and very inexpensive alternative to synthetic food additives. However, the conditions in which the antioxidants are extracted must be optimized. This work proves that conditions such as extraction solvent or temperature have a crucial impact on obtaining extracts rich in antioxidants from mango biowastes.     

Phenolic composition of Merlot and Cabernet-Sauvignon grapes from Bordeaux vineyard for the 2009-vintage: Comparison to 2006, 2007 and 2008 vintages

Cabernet-Sauvignon and Merlot skin and seed extracts from Bordeaux grapes were investigated to determine both grape variety and vintage effect on phenolic composition. The total content of polyphenols and tannins in Merlot seeds was higher than that of Cabernet-Sauvignon allowing to discriminate the varieties. HPLC analyses underlined significant differences in the absolute concentration of proanthocyanidins amongst the two varieties and in their composition: mean degree of polymerisation (mDP) and percentage of galloylation of seed extracts were good indicators of grape variety. The vintage effect on the phenolic composition was confirmed for 2009 in comparison to previous vintages. Low values of mDP and concentrations of proanthocyanidins and anthocyanins were found in 2009 seeds and skins. The climatic conditions of 2009 (high rainfall before flowering followed by a strong hydric stress during berries development until ripening) let us hypothesise a lower activation of flavonoid pathway.     

Effect of Processing on the Content of Condensed Tannins in Rapeseed Meals

The condensed tannins of rapeseed meals produced by a two-phase solvent extraction system were determined and compared with those of hexane-extracted meals. Ground seeds were extracted with absolute methanol, 95% methanol, 10% (w/w) ammonia in methanol or 10% (w/w) ammonia in 95% methanol and hexane as a second phase. Tannins were extracted with 70% (v/v) aqueous acetone and assayed by the 0.5% vanillin methodology. Methanol alone extracted only 16% of the tannins; addition of 5% (v/v) water to methanol increased the efficiency of tannin extraction to 36%. The methanol-ammonia-water/hexane, however, was the most effective solvent system for the removal of tannins. The resultant meals contained from 4% to 33% of the condensed tannins which were originally present in rapeseed meals.     

白骨壤种子中总黄酮的提取及抗氧化性研究

采用乙醇恒温水浴法对白骨壤种子中总黄酮提取和L(934)正交试验设计进行优化,并采用Schaal烘箱法研究总黄酮的抗氧化性。结果表明,总黄酮最佳提取条件为料液比1∶30(g/mL)、提取温度60℃、提取时间4.5 h和乙醇浓度60%,且该条件下总黄酮提取率可达5.89%;白骨壤种子总黄酮对大豆油有一定的抗氧化效果,且具有量效关系;相同添加量下,抗氧化效果由强到弱的顺序为0.02%TBHQ>0.02%BHT>0.02%总黄酮;总添加量为0.06%时,其表现出的抗氧化效果和0.02%TBHQ效果相接近。     

Effects of extraction conditions on improving the yield and quality of an anthocyanin-rich purple corn (Zea mays L.) color extract

ABSTRACT:  Purple corn ( Zea mays L.) is a rich and economic source of anthocyanin colorants and functional ingredients. However, high levels of anthocyanin-rich waste are generated during processing, reducing the yields and increasing the costs of the final product. This waste has been associated with anthocyanin complexation with tannins and proteins. Our objective was to evaluate anthocyanin extraction methods to reduce purple corn waste. Different solvents (water, 0.01%-HCl-acidified water, and 0.01%-HCl-acidified ethanol), temperatures (room temperature, 50, 75, and 100 °C), and times of exposure to the solvents were investigated. Acetone (70% acetone in water) extraction was used as control. Anthocyanins, total phenolics, tannins, and proteins in extracts were measured by the pH differential, Folin-Ciocalteu, protein precipitation, and BCA assay methods. Qualitative analyses were done by HPLC coupled to a PDA detector and SDS-PAGE analysis. Water at 50 °C achieved the highest yield of anthocyanins (0.94 ± 0.03 g per 100 g dry corncob) with relatively low tannins and proteins, comparable to the anthocyanin yield obtained by 70% acetone (0.98 ± 0.08 g per 100 g dry corncob). Extending the extraction time from 20 to 60 min and using consecutive reextraction procedures reduced anthocyanin purity, increasing the yields of other phenolics. A neutral protease was applied to the extracts and effectively decomposed the major protein that was believed to contribute to the development of anthocyanin complexation and waste generation. Extraction time, consecutive reextraction procedures, and enzyme hydrolysis should be considered for high yield of anthocyanins and waste reduction.     

Seed maturity differentially mediates metabolic responses in black soybean

The soybean seed is placed in the middle of the morphological and developmental alterations, such as changes in seed size, weight, and colour, and alteration of the composition and contents of metabolites during maturation. In this study, we used black soybean seeds to investigate the effect of maturity on metabolite levels at different maturity stages. Seeds were sorted into five maturity categories, from M1 to M5, based on seed size and external pigmentation. Maturity stages M1, M3, and M5 are equivalent to R6, R7, and R8 on the soybean reproductive growth stage scale, indicating full seed, beginning maturity, and full maturity, respectively. As seed maturation progressed, the seed size decreased and the water soluble extract changed, indicating that a change of seed pigmentation occurred. At the same time, numerous metabolites responded differentially to seed maturation. The partial least squares (PLS) scores plot indicated that the metabolic alteration during maturation was clearly visible. Furthermore, isoflavones were highly associated with seed maturity on the PLS loading plot while fatty acids, glucose, fructose, and sucrose were less linked with seed maturity, indicating that those metabolites responded less to seed maturation. Overall, the results indicate that each category of metabolites is mediated differentially during maturation in black soybean seeds.     

A systematic approach for extraction of phenolic compounds using parsley (Petroselinum crispum) flakes as a model substrate

The impact of extraction methodology and polarity of extraction solvents on the assay of phenolic compounds was investigated using parsley (Petroselinum crispum) flakes as a model substrate. This systematic study was undertaken to address substantial variations in the extraction procedures, solvents and conditions as described in the recent literature. Five different extraction procedures [shaking, vortex mixing, sonication, stirring and pressurized liquid extraction (PLE)] and three different solvents (methanol, ethanol and acetone), with five different solvent to water ratios per solvent, were used for extraction. Extracts were analyzed for phenolic content by high‐performance liquid chromatography and Folin–Ciocalteu assays. The yields of phenolic compounds extracted with a pressurized liquid extractor were comparable to or better than those of four classical extraction procedures. Optimum extraction efficiency with PLE was obtained when extractions were performed with four extraction cycles using ethanol–water (50:50, v/v). The amount of apiin (4,5,7‐trihydroxyflavone 7‐apiosylglucoside) and malonylapiin (apigenin malonylapiosylglucoside) isolated from parsley varied with the composition of extraction solvent. Apiin extractability was found to be a maximum when the solvent (ethanol, methanol or acetone) to water ratio was 30:70 (v/v), whereas higher amounts of malonylapiin were isolated with a reverse solvent to water ratio (70:30, v/v). Malonylapiin was not detected when parsley samples were extracted with organic solvent to water ratios of 10:90 (v/v) and 30:70 (v/v). Published in 2006 by John Wiley & Sons, Ltd     

杏仁皮单宁提取工艺优化及其DPPH自由基清除活性

以杏仁皮单宁得率为指标,考察了料液比、提取时间、提取温度、乙醇体积分数四个因素对杏仁皮单宁提取效果的影响。在单因素基础上,采用响应面法优化杏仁皮单宁提取工艺,并对最佳工艺下所得杏仁皮单宁的DPPH自由基清除活性进行测试。结果表明:所建立的杏仁皮单宁提取工艺模型极显著,其最优实验条件是料液比1:22 (g/mL)、提取时间89 min、提取温度70 ℃、乙醇体积分数50%,在此条件下杏仁皮单宁得率为2.13%。杏仁皮单宁浓度为250 μg/mL时对DPPH自由基的清除率达到98.65%,表明杏仁皮单宁具有较强的抗氧化活性。     

Influence of the heterogeneity of grape phenolic maturity on wine composition and quality

Nowadays, consumers demand red wines with deep colour, soft tannins and fruit scents, but these wines can only be obtained from grapes with complete phenolic maturity. Diverse methods have been proposed for measuring phenolic maturity. However, all these methods only provide the average value and do not consider any possible heterogeneity. Throughout ripening, grapes were separated according to their density, which revealed the existence of a large heterogeneity. Grapes at harvest were also separated by density in three groups. The higher the density of the grapes the higher ethanol content, pH, colour intensity, total phenolic index and anthocyanin and proanthocyanidin concentrations, and the lower the titratable acidity and bitterness of the wines. When the grapes were denser the wines were also better balanced in flavour and mouthfeel sensation. These results suggest that grape heterogeneity may influence the final wine composition and quality and therefore it should be considered at harvest.     

女贞果实的抗氧化性测定

以南京产女贞果实为原料,考察不同提取剂对女贞果实不同部位(全果、果皮、核壳和果仁)提取所得提取液对DPPH 自由基的清除效果,比较向阳面和向阴面不同生长期女贞果实的乙醇提取液对DPPH 自由基的清除效果,研究固体状乙醇提取物的抗氧化性,测定女贞果实抗氧化的主要化学成分和固体状乙醇提取物的感官指标。结果表明：极性溶剂提取液表现出较强的清除DPPH 自由基的能力;不同提取剂对女贞果实不同部位的提取物清除DPPH 自由基能力的顺序为：甲醇、水的提取物为果皮＞全果＞核壳＞果仁,丙酮、乙酸乙酯、乙醇的提取物为果皮＞全果＞果仁＞核壳;提取物在低浓度区对DPPH 自由基的清除作用与浓度成正相关,且斜率大大高于高浓度区,而高浓度区对DPPH 自由基的清除作用与浓度的关系较复杂,表现为与提取剂密切相关。另外果实以成熟初期的提取物对DPPH 自由基清除率最高,在成熟中期和过成熟期后均有不同程度下降,而且向阳面生长果实提取物对DPPH 自由基的清除率显著高于向阴面果实提取物。抗氧化比较实验得到所制备的固体状女贞全果乙醇提取物抗氧化效果(IC50=5.38～10.46)与VC(IC50=8.59)相当,低于茶多酚(IC50 =1.70)。另外,水溶性好、呈深咖啡色固体状的乙醇提取物有望成为一种新型高效抗氧化剂。