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1.
Andean blueberry (Vaccinium meridionale Swartz) fruits are an underutilized source of anthocyanins and other valuable bioactive phytochemicals. The purpose of this work was to obtain Andean blueberry juice powders via freeze-drying processing and evaluate the effect of maltodextrin as a drying aid on their physicochemical, technological, microstructural, and bioactive characteristics. Andean blueberry juices were mixed with variable proportions of maltodextrin (20–50%); freeze-dried; and characterized in terms of their tristimulus color, Fourier transform infrared spectra (FTIR), moisture content, water activity, morphology, water solubility, flow properties, total polyphenols and anthocyanins content, and DPPH-scavenging capacity. The powders obtained presented suitable characteristics in terms of their water activity (<0.5), solubility (>90%), and bioactive compound recovery (>70% for total phenolics, and >60% for total monomeric anthocyanins), with antioxidant activities up to 4 mg equivalent of gallic acid/g of dry matter. Although an increased content of maltodextrin resulted in lower concentrations of phytochemicals, as expected, it also favored an increased % recovery (over 90% of total phenolics at the highest maltodextrin proportion) and improved their flow properties. Freeze-dried juice powders are a potential alternative for the stabilization and value addition of this fruit as a new source of functionality for processed foods.  相似文献   
2.
Non-thermal preservation technologies such as high pressure processing (HPP) have low impact in original fruit flavours. The objective of this study was to process the whole blueberries by HPP and investigate the effect on its hardness after processing and during 7 and 28 days storage. Whole blueberry immersed in water was the best packaging option. The blueberries submitted to 200 and 600?MPa for 5–60?min and were stored at 3°C for 1 week. In another experiment, HPP blueberries (200 and 600?MPa for 10?min) were stored for 28 days. No difference in sensorial texture was observed between HPP and fresh unprocessed blueberry, although the instrumental hardness decreased significantly. Hardness was not affected by the processing time and was similar just after HPP and one-week storage. The hardness of HPP-processed blueberries was kept along 28 days storage without considerable weight loss as opposed to fresh fruits which collapsed.  相似文献   
3.
Hanseniaspora uvarum, a non-Saccharomyces cerevisiae species, has a crucial effect on the aroma characteristics of fruit wines, thus, attracting significant research interest in recent years. In this study, H. uvarumSaccharomyces cerevisiae mixed fermentation was used to ferment Rosa roxburghii Tratt, blueberry fruit wine, and plum fruit wines using either a co-inoculated or a sequentially inoculated approach. The three fruit wines’ volatile aroma characteristics were analyzed by headspace–solid-phase microextraction–gas chromatography-mass spectrometry (HS–SPME–GC–MS). The results showed that the mixed inoculation of H. uvarum and S. cerevisiae reduced the alcoholic content of Kongxinli fruit wine. Moreover, H. uvarumS. cerevisiae fermented Rosa roxburghii Tratt, blueberry, and plum fruit wines and further enriched their flavor compounds. The overall flavor characteristics of sequentially inoculated fruit wines differed significantly from those fermented with S. cerevisiae alone, although several similarities were also observed. Sequential inoculation of H. uvarum and S. cerevisiae positively affected the mellowness of the wine and achieved a better harmony of the overall wine flavors. Therefore, H. uvarumSaccharomyces cerevisiae mixed fermentation can improve the complexity of the wines’ aromatic composition and empower them with a unique identity. In particular, H. uvarumSaccharomyces cerevisiae blueberry wine produced by mixed fermentation had the widest variety and content of aroma compounds among the fermented wines. Therefore, H. uvarumSaccharomyces cerevisiae mixed-fermentation inoculation in the three fermented fruit wines significantly increased the aroma compound variety and content, thus, enriching their aroma richness and complexity. This study is the first comparative evaluation of the aroma characteristics of different fruit wines fermented with a mixed inoculation of H. uvarum and S. cerevisiae and provides a preliminary guide for these fruit wines produced with non-Saccharomyces yeast.  相似文献   
4.
This research was conducted in order to establish the effectiveness of two freeze-dried extracts obtained from blueberry processing byproducts resulting from juice manufacturing compared to butylated hydroxytoluene (BHT) in delaying the lipid oxidation of sunflower oil subjected to high-temperature convective heating at 180 °C up to 12 h under simulated frying conditions. The fruits were harvested from spontaneous flora of two regions of Romania, Arieseni (Alba County) and Paltinis (Sibiu County) and the blueberry byproducts extracts (BBE) were noted according to the origin place as ABBE and PBBE. The progress of lipid thermo-oxidation was investigated in terms of peroxide value (PV), p-anisidine value (p-AV), the response of TBA-malondialdehyde interactions assessed by thiobarbituric acid (TBA) method, the total oxidation (TOTOX) value and inhibition of oil oxidation (IO). The recorded data highlighted that BBE exhibit a high inhibitory response on lipid thermo-oxidation. The inhibitory effect was concentration-dependent, thus, the degree of lipid oxidation was in reverse related to the BBE dose. The exposure of the oil samples supplemented with 800 ppm BBE (ABBE, PBBE) to a high-temperature heating for 12 h led to a significant decrease of the assessed indices compared to additives-free sunflower oil sample as follows: PV (46%; 45%), p-AV (21%; 17%), TOTOX (27%; 24%), TBA value (25%; 11%). Regarding the impact of the origin on the potential of BBE to inhibit the lipid oxidative degradation, it was noted that ABBE derived from blueberries grown in a region with a milder climate with moderate precipitations and higher temperatures showed a stronger inhibitory effect on lipid thermo-oxidation than PBBE. A moderate level of 500 ppm BBE inhibited the lipid oxidation similar to 200 ppm BHT. The reported results reveal that BBE represent efficient natural antioxidants that could be successfully applied to improve the thermo-oxidative stability of sunflower oil used in various high-temperature food applications.  相似文献   
5.
Nowadays, it is largely accepted that the daily intake of fruits, vegetables, herbal products and derivatives is an added value in promoting human health, given their capacity to counteract oxidative stress markers and suppress uncontrolled pro-inflammatory responses. Given that, natural-based products seem to be a promising strategy to attenuate, or even mitigate, the development of chronic diseases, such as diabetes, and to boost the immune system. Among fruits, cherries and blueberries are nutrient-dense fruits that have been a target of many studies and interest given their richness in phenolic compounds and notable biological potential. In fact, research has already demonstrated that these fruits can be considered functional foods, and hence, their use in functional beverages, whose popularity is increasing worldwide, is not surprising and seem to be a promising and useful strategy. Therefore, the present review reinforces the idea that cherries and blueberries can be incorporated into new pharmaceutical products, smart foods, functional beverages, and nutraceuticals and be effective in preventing and/or treating diseases mediated by inflammatory mediators, reactive species, and free radicals.  相似文献   
6.
The aim of the present study was to determine the major anthocyanins of blueberry extracts from northeast China and explore their vision health improvement effects. HPLC-Q-TOF-MS/MS results suggested that six different anthocyanins were accurately identified, among which the Cy-3-glu (C3G) was the most abundant, ranging from 376.91 ± 7.91 to 763.70 ± 4.99 μM. The blueberry extract contained a higher purity of anthocyanins, and the anthocyanosides reached 342.98 mg/kg. The anti-oxidative stress function of C3G on HG-treated ARPE-19 cells were evaluated, and showed that the GSSG level of HG-cells pretreated with 10 μM C3G was significantly decreased, while the Nrf2 and NQO1 gene expression levels were increased. Further molecular docking (MD) results indicated that the C3G displayed favorable binding affinity towards REDD1, and only the B-ring of the C3G molecule displayed binding interactions with the CYS-140 amino acids within the REDD1 protein. It implied that the oxidative stress amelioration effects of C3G on the ARPE-19 cells were related to the REDD1 protein, which was probably via the Nrf2 pathways, although further studies are needed to provide mechanism evidence. The present study provides novel insights into understanding the roles of blueberry anthocyanins in ameliorating oxidative stress-induced BRB damage in the retina.  相似文献   
7.
Blueberry wine residues produced during the wine-brewing process contain abundant anthocyanins and other bioactive compounds. To extract anthocyanins from blueberry wine residues more efficiently, a novel procedure of ultrasound-assisted deep eutectic solvent extraction (UADESE) was proposed in this work. The extraction process was optimized by response surface methodology coupled with genetic algorithm. The optimum extraction parameters to achieve the highest yield of anthocyanins (9.32 ± 0.08 mg/g) from blueberry wine residues by UADESE were obtained at water content of 29%, ultrasonic power of 380 W, extraction temperature of 55 °C, and extraction time of 40 min. The AB-8 macroporous resin combined with Sephadex LH-20 techniques was used to purify the crude extract (CE) obtained under optimum extraction conditions and analyze the anthocyanins composition by HPLC-ESI-MS/MS. The cyanidin-3-rutinoside with purity of 92.81% was obtained. The HepG2 antitumor activity of CE was better than that of the purified anthocyanins component. Moreover, CE could increase the intracellular reactive oxygen species levels and the apoptosis, and arrest HepG2 cells in the S phases. These findings provided an effective and feasible method for anthocyanins extraction, and reduced the environmental burden of this waste.  相似文献   
8.
HPLC-ESI-MS/MS识别蓝莓提取物中的花青素和黄酮醇   总被引:2,自引:0,他引:2  
用高效液相色谱-电喷雾离子化串联质谱联用技术(HPLC-ESI-MS/MS)对蓝莓提取物中的黄酮类物质进行了分析, 可以快速地鉴定其主要成分为花青素和黄酮醇. 结构上的不同导致花青素和黄酮醇在紫外-可见光谱吸收、离子化以及裂解方式上都存在差异. 尽管花青素和黄酮醇在270 nm处都有吸收, 但两者分别在530和372 nm附近有特征吸收. 负离子模式下, 黄酮醇可以生成负离子和自由基负离子, 而正离子型的花青素则几乎不产生质谱信号, 这一显著差异可用以区别花青素和黄酮醇. 花青素与黄酮醇在串联质谱中分别拥有各自的特征产物离子更进一步证实了其结构存在差别. 该研究对于蓝莓提取物的质量分析与控制很有帮助.  相似文献   
9.
The aging process impacts neural stem cells and causes a significant decline in neurogenesis that contributes to neuronal dysfunction leading to cognitive decline. Blueberries are rich in polyphenols and have been shown to improve cognition and memory in older humans. While our previous studies have shown that blueberry supplementations can increase neurogenesis in aged rodents, it is not clear whether this finding can be extrapolated to humans. We thus investigated the effects of blueberry treatments on adult hippocampal human neural progenitor cells (AHNPs) that are involved in neurogenesis and potentially in memory and other brain functions. Cultured AHNPs were treated with blueberry extract at different concentrations. Their viability, proliferation, and differentiation were evaluated with and without the presence of a cellular oxidative stressor, dopamine, and potential cellular mechanisms were also investigated. Our data showed that blueberry extract can significantly increase the viability and proliferation rates of control hippocampal AHNPs and can also reverse decreases in viability and proliferation induced by the cellular stressor dopamine. These effects may be associated with blueberry’s anti-inflammatory, antioxidant, and calcium-buffering properties. Polyphenol-rich berry extracts thus confer a neuroprotective effect on human hippocampal progenitor cells in vitro.  相似文献   
10.
岳玉华  周炳均  艾佳媛  封顺 《色谱》2020,38(11):1302-1307
达卡巴嗪是治疗恶性黑色素瘤的一线化疗药物。它在体内主要经肝脏代谢,同时部分药物仍以原药形式经尿液排出。这就意味着可以通过监测尿液中达卡巴嗪的含量评估其在人体内的利用率和转化率,进而对其治疗效果进行评价。针对达卡巴嗪,人们发展了多种分析方法,但多基于高效液相色谱-质谱平台。然而达卡巴嗪为强极性弱碱性化合物,采用常规反相色谱法分析时会出现出峰时间过早、峰形拖尾的现象,导致定量不准确。基于此,该文建立了一种测定尿液中达卡巴嗪含量的高效液相色谱方法以克服上述问题。小鼠尿液经丙酮沉淀法去除蛋白后,采用Shimadzu-GL ODS柱(150 mm×4.6 mm, 5μm)分离,色谱条件如下:流动相为甲醇/乙腈(1∶1, v/v)-0.01 mol/L磷酸二氢钠溶液(pH=6.5)(20∶80, v/v),流速1 mL/min,检测波长280 nm,柱温35℃,洗脱时间15 min。在该色谱条件下,达卡巴嗪保留时间为5.3 min且峰形良好。其在0.25~1 000μg/mL范围内线性关系良好(r2=0.999)。基于信噪比(S/N)=3和S/N=10,计算出检出限和定量限分...  相似文献   
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