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51.
The by-products/wastes from agro-food and in particular the fruit industry represents from one side an issue since they cannot be disposed as such for their impact on the environment but they need to be treated as a waste. However, on the other side, they are a source of bioactive healthy useful compounds which can be recovered and be the starting material for other products in the view of sustainability and a circular economy addressing the global goal of “zero waste” in the environment. An updated view of the state of art of the research on fruit wastes is here given under this perspective. The topic is defined as follows: (i) literature quantitative analysis of fruit waste/by-products, with particular regards to linkage with health; (ii) an updated view of conventional and innovative extraction procedures; (iii) high-value added compounds obtained from fruit waste and associated biological properties; (iv) fruit wastes presence and relevance in updated databases. Nowadays, the investigation of the main components and related bioactivities of fruit wastes is being continuously explored throughout integrated and multidisciplinary approaches towards the exploitation of emerging fields of application which may allow to create economic, environmental, and social value in the design of an eco-friendly approach of the fruit wastes.  相似文献   
52.
气相色谱-质谱法分析山楂果中的有机酸   总被引:4,自引:0,他引:4  
山楂(Hawthorn),别名红果,蔷薇科山楂属(Crataegus)植物,山楂果营养丰富,是最早被列入食药兼用的水果之一,具有消食化滞,行气散瘀等功效。山楂果中起消食导滞作用的有效成分是有机酸。本文对文献的实验条件进行合理改进,用GC—MS法对河南辉县和桐柏山两地山楂果中有机酸成分进行了系统分析,各有机酸成分得到有效分离;并利用选择离子方法测定了其中8种主要有机酸的含量,以期对山楂果的食用、药用价值以及开发研制功能性保健食品提供科学依据。  相似文献   
53.
An on-line flow injection system has been developed for the selective determination of Se(IV) and Se(VI) in citric fruit juices and geothermal waters by hydride generation atomic absorption spectrometry with microwave-aided heating prereduction of Se(VI) to Se(IV). The samples and the prereductant solutions (4 mol l−1 HCl for Se(IV) and 12 mol l−1 HCl for Se(VI)) which circulated in a closed-flow circuit were injected by means of a time-based injector. This mixture was displaced by a carrier solution of 1% v/v of hydrochloric acid through a PTFE coil located inside the focused microwave oven and mixed downstream with a borohydride solution to generate the hydride. The linear ranges were 0–120 and 0–100 μg l−1 of Se(IV) and Se(VI), respectively. The detection limits were 1.0 μg l−1 for Se(IV) and 1.5 μg l−1 for Se(VI). The precision (about 2.0–2.5% RSD) and recoveries (96–98% for Se(IV) and 94–98% for Se(VI)) were good. Total selenium values were also obtained by electrothermal atomic absorption spectrometry which agreed with the content of both selenium species. The sample throughput was about 50 measurements per hour. The main advantage of the method is that the selective determination of Se(IV) and Se(VI) in citric fruit juices and geothermal waters is performed in a closed system with a minimum sample manipulation, exposure to the environment, minimum sample waste and operator attention.  相似文献   
54.
In this study, an overall survey regarding the determination of several bioactive compounds in olive fruit is presented. Two methodologies were developed, one UPLC-Q-TOF-MS method for the determination of olive fruit phenolic compounds and one HPLC-DAD methodology targeting the determination of pigments (chlorophylls and carotenoids), tocopherols (α-, β, -γ, δ-) and squalene. Target and suspect screening workflows were developed for the thorough fingerprinting of the phenolic fraction of olives. Both methods were validated, presenting excellent performance characteristics, and can be used as reliable tools for the monitoring of bioactive compounds in olive fruit samples. The developed methodologies were utilized to chemical characterize the fruits of the Kolovi olive variety, originating from the island of Lesvos, North Aegean Region, Greece. Twenty-five phenolic compounds were identified and quantified in Kolovi olives with verbascoside, hydroxytyrosol, oleacein and oleomissional found in significantly high concentrations. Moreover, 12 new bioactive compounds were identified in the samples using an in-house suspect database. The results of pigments analysis suggested that Kolovi variety should be characterized as low pigmentation, while the tocopherol and squalene content was relatively high compared to other olive varieties. The characterization of Kolovi olive bioactive content highlighted the high nutritional and possible economic value of the Kolovi olive fruit.  相似文献   
55.
陈刚  张建甲  张洁  张黎 《化学教育》2015,36(8):58-60
设计了应用废弃果皮制备绿色钻井液添加剂的综合性实验,评价其对钻井液性能的影响.该实验将油田化学理论基础与实验技术、现场实践相结合,能够提高学生的专业实验技能、分析和解决问题的能力,同时采用废弃果皮作为实验原料,可提高学生的环保意识,有助于将环保理念注入日后油田生产中.  相似文献   
56.
 为了研究超高压处理对荔枝果肉中过氧化物酶(POD)、果胶甲基酯酶(PME)及可溶性蛋白含量的影响,将荔枝(“淮枝”品种)果肉在100~400 MPa压力、10 ℃温度条件下处理30 min,采用分光光度法测定果肉中POD、PME的活性,用天然凝胶电泳法以及活性染色法测定POD、PME同工酶的变化,用SDS凝胶电泳法测定果肉中可溶性蛋白含量。结果表明:100~200 MPa超高压处理使荔枝果肉中POD活性上升且出现新的同工酶,300~400 MPa超高压处理则使其活性降低且新出现的同工酶消失;100 MPa压力处理使荔枝果肉中PME活性上升且出现新的同工酶,200~400 MPa超高压处理则使其活性降低且新出现的同工酶消失;100 MPa超高压处理使荔枝果肉中可溶性蛋白含量有所增加,而在200~400 MPa压力处理下其含量持续下降。  相似文献   
57.
Among the many species of native fruit of Brazil that have been little explored, there is Myrciaria floribunda (also known as rumberry, cambuizeiro, or guavaberry), a species with significant variability, which has fruits of different colors (orange, red, and purple) when ripe. The physical-chemical characteristics evaluated were fruit weight (FW), seed weight (SW), pulp weight (PW), number of seeds (NS), longitudinal diameter (LD), transverse diameter (TD), format (LD/TD), hydrogen potential (pH), soluble solids (SS), titratable acidity (TA), and ratio (SS/TA); further, the volatile organic compounds (VOCs) of nine accesses of rumberry orchards were identified. The averages of the variables FW, SW, PW, NS, LD, TD, shape, and firmness were 0.76 g, 0.22 g, 0.54 g, 1.45, 10.06 mm, 9.90 mm, 1.02, 2.96 N, respectively. LD/TD data showed that the fruits have a slightly rounded shape (LD/TD = 1). The averages for pH, SS, TA, and SS/TA were 3.74, 17.58 Brix, 4.31% citric acid, and 4.31, respectively. The evaluated parameters indicated that the fruits can be consumed both in natura and industrialized, with the red-colored fruits presenting a good balance of SS/TA, standards demanded by the processing industries. Thirty-six VOCs were identified, with emphasis on the sesquiterpenes. Caryophyllene (21.6% to 49.3%) and γ-selinene (11.3% to 16.3%) were the most predominant compounds in rumberry fruits.  相似文献   
58.
建立了液相色谱–三重四极杆串联质谱测定水果及其制品中氯吡脲的方法。样品经乙腈提取,氨基固相萃取小柱净化后,用ZORBAX Extend-C18柱(150 mm×2.1 mm,5μm)分离,以甲醇–水为流动相等度洗脱,采用多反应监测正离子模式检测,外标法定量。氯吡脲的质量浓度在4.0~200.0 ng/m L范围内线性良好,相关系数大于0.999,在5.0,10.0,20.0μg/kg 3个添加水平下,氯吡脲的平均加标回收率为86%~92%,测定结果的相对标准偏差为5.3%~7.6%(n=5),方法定量下限为2.0μg/kg。方法灵敏度高,操作简便,定量准确,可满足梨、柑桔、黄桃等水果及其罐头制品中氯吡脲残留的检测与确证需要。  相似文献   
59.
张志勇  单炜力  简秋  段丽芳  沈燕  刘贤金 《色谱》2012,30(9):962-965
建立了一种通过检测硝苯菌酯(2,4-dinitro-6-(1-methylheptyl) phenyl crotonate, 2,4-DNOPC)相应的水解产物2,4-二硝基-6-(1-甲基庚基)苯酚(2,4-dinitro-6-(1-methylheptyl) phenol, 2,4-DNOP)来测定蔬菜和水果中2,4-DNOPC残留量的液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)检测方法。蔬菜和水果样品用丙酮-甲醇-盐酸的混合液进行液-液分配提取,在碱性条件下超声水解后再进行液-液分配提取,然后进行LC-MS/MS测定。2,4-DNOPC在6种蔬菜和水果中的回收率试验结果表明,2,4-DNOPC在甘蓝中的添加回收率为89.7%~93.3%,相对标准偏差(RSD)为6.3%~8.5%;在黄瓜中的添加回收率为87.7%~95.1%, RSD为5.8%~10.4%;在番茄中的添加回收率为89.3%~96.0%, RSD为6.8%~9.2%;在苹果中的添加回收率为92.0%~98.3%, RSD为5.1%~10.3%;在梨中的添加回收率为89.0%~95.0%, RSD为5.3%~10.2%;在葡萄中的添加回收率为81.2%~95.8%, RSD为5.8%~10.4%。2,4-DNOPC在6种蔬菜和水果的最低检测浓度均为0.01 mg/kg。该检测方法样品前处理简单、快速,分析时间短,灵敏度、准确度和精密度均符合农药残留检测要求,适用于蔬菜和水果中硝苯菌酯残留量的检测。  相似文献   
60.
Jin Y  Wang M 《色谱》2012,30(1):67-70
将四甲氧基硅烷(TMOS)水解后与烯唑醇抗体聚合,采用溶胶-凝胶法合成了烯唑醇免疫亲和色谱(IAC)柱固定相,并用其制备了对烯唑醇具有特异性亲和力的IAC柱。对IAC柱条件进行了优化,选择超纯水作为吸附与平衡介质,30%~50%(体积分数)甲醇水溶液作为洗脱剂。结果表明: 在优化条件下,IAC柱对烯唑醇的动态柱容量达125.4 μg/g。在河水样品和水果样品中添加烯唑醇,经IAC柱净化富集,洗脱液采用高效液相色谱检测,河水中烯唑醇的平均回收率为90.36%~100.14%,相对标准偏差(RSD)为2.03%~6.08%;水果中烯唑醇的平均回收率为85.55%~94.02%, RSD为3.38%~6.78%。本研究为烯唑醇在河水、水果等样品中的残留分析提供了一种新的高效前处理手段。  相似文献   
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