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101.
M. Nasiruddin Khan Anila Sarwar M. Farooq Wahab Roohi Haleem 《Journal of the science of food and agriculture》2008,88(6):1051-1059
BACKGROUND: The fruit of date palm is consumed as an ideal high‐energy food. It is also used for the treatment of colds, fever, liver and abdominal troubles. Its nutritional composition strongly depends upon variety and ripening stage. A number of varieties are available in Pakistan but little is known about their composition and nutritional characteristics. Inherent moisture, volatile matter, ash, fixed carbon, sugar and mineral metals of seven commercial date varieties (Aseel, Basra, Begun, Janshoor, Mazoee, Rabee and Zaidi) were investigated. The physical and chemical compositions with respect to maturation were also monitored for the Aseel variety. RESULTS: The results showed significant varietal differences in moisture, ash and mineral metal composition when analysis of means was conducted at an alpha level of 0.05. The difference between means was insignificant (P > 0.05) for volatile matter, glucose, fructose and total reducing sugars. All varieties were found to be an excellent source of total reducing sugar (78%), potassium (403–632 mg per 100 g) and calcium (27.41–81.47 mg per 100 g). A gradual increase in total reducing sugar and minerals, especially potassium and copper, was observed with maturation. Variety Aseel was grouped on the basis of maturation using principal component analysis. Local date varieties were separated with 48.63% level of similarity from Iranian variety (29.17%) using Cluster analysis. CONCLUSION: This study provides an overview of the physico‐chemical properties of date varieties. The sample varieties showed significant differences except for sugar and volatile matter. Multivariate analysis was found to be an important statistical tool for the separation of samples on the basis of geographical origin and maturations. Copyright © 2008 Society of Chemical Industry 相似文献
102.
103.
Priyal Sharma Mahesh Kumar Saini Jagdish Prasad Vinod Singh Gour 《Journal of surfactants and detergents》2019,22(2):403-408
Balanites aegyptiaca (L.) Del. is a widely distributed xerophytic multipurpose tree. The mesocarp of the fruit of B. aegyptiaca has detergent properties due to the presence of saponins. The stability potential of this biosurfactant at varying pH, temperature, and salinity has not been explored so far. In the present study, the relative surface tensions of five different concentrations of the biosurfactant were studied at different temperatures, salinity, and under pH conditions. This study reveals that this biosurfactant retains its activity over a wide range of pH (3–11) and at high salinity (7% NaCl). It is a thermostable cationic surfactant; surfactant activity was recorded even at 100 °C with the lowest relative surface tension of 0.47. High oil displacement (18.00 mm) was observed when studied with petrol. This biosurfactant was found to have a high emulsification index (E24) of 70% with mustard oil. These results indicate that biosurfactant derived from B. aegyptiaca may find use in a wide range of sectors such as textile, food, cosmetics, oil recovery, and healthcare under a wide range of physical and chemical conditions. It offers an efficient, economically viable, and plant-derived alternative to synthetic detergents and adds a way to maintain a sustainable environment. 相似文献
104.
为研究新疆各产地西拉酿酒葡萄成熟指标的变化规律及其最适采收期,自果实转色期开始,以不同采收期哈密、昌吉及和硕西拉葡萄为研究对象,持续监控其理化指标和酚类物质含量变化,分析理化指标与多酚指标的相关性,并对不同产地及采收期的西拉酿酒葡萄进行主成分分析(PCA),确定最适采收期。结果表明,不同采收期各产地西拉葡萄理化指标及多酚含量差异显著(P<0.05),且理化指标与多酚含量联系紧密;主成分分析结果表明,哈密、昌吉及和硕西拉葡萄最适采收期分别为9月9日、9月11日及9月3日。 相似文献
105.
旨在采用液态静止表面发酵法,通过正交实验对红枣醋的醋酸发酵过程进行优化。得出醋酸发酵的最佳条件为温度32℃、酒精度6%、接种量10%、初始pH4.4,醋酸发酵结束后各项指标均符合国家食醋卫生标准,且红枣醋的Vc含量明显高于其他类型的果醋。 相似文献
106.
用不同体积分数的乙醇(30%、60%、80%和100%)提取黑枣中的酚类物质,通过测定各提取物的总酚含量,确定提取溶剂的适宜浓度为80%(总酚含量为3.5mg/g)。在此基础上,以DPPH自由基法、OH·自由基法、Fe~(3+)还原力法和Fe~(2+)络合力法对黑枣提取物的抗氧化活性进行了评价。结果表明:黑枣80%乙醇提取物具有较强的抗氧化活性,且其DPPH自由基、OH·自由基清除能力和Fe~(3+)还原能力均呈现剂量-效应关系,Fe~(2+)络合能力相当于5.64mgNa_2EDTA。 相似文献
107.
Khawaja Ghulam Rasool Muhammad Altaf Khan Abdulrahman Saad Aldawood Muhammad Tufail Muhammad Mukhtar Makio Takeda 《International journal of molecular sciences》2015,16(8):19326-19346
A state of the art proteomic methodology using Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI TOF) has been employed to characterize peptides modulated in the date palm stem subsequent to infestation with red palm weevil (RPW). Our analyses revealed 32 differentially expressed peptides associated with RPW infestation in date palm stem. To identify RPW infestation associated peptides (I), artificially wounded plants (W) were used as additional control beside uninfested plants, a conventional control (C). A constant unique pattern of differential expression in infested (I), wounded (W) stem samples compared to control (C) was observed. The upregulated proteins showed relative fold intensity in order of I > W and downregulated spots trend as W > I, a quite interesting pattern. This study also reveals that artificially wounding of date palm stem affects almost the same proteins as infestation; however, relative intensity is quite lower than in infested samples both in up and downregulated spots. All 32 differentially expressed spots were subjected to MALDI-TOF analysis for their identification and we were able to match 21 proteins in the already existing databases. Relatively significant modulated expression pattern of a number of peptides in infested plants predicts the possibility of developing a quick and reliable molecular methodology for detecting plants infested with date palm. 相似文献
108.
The importance, benefits, and impact of integration of decisions within supply chains have long been investigated by many researchers. Order acceptance and supplier selection are two of the most critical decisions for supply chain managers. Throughout the process of order acceptance, a manufacturer has to decide which orders to be accepted and processed and based on the accepted orders, the volume of required raw material is determined. On the other hand, a manufacturer aims to choose one or several suppliers among all possible choices to provide sufficient raw material for the accepted orders, subject to different criteria such as list price, transportation cost, etc. This paper addresses an integrated framework for profit maximization in an integrated supplier selection, order acceptance and scheduling problem in a single-machine environment with multiple customers. There is substantial literature on the problems of supplier selection and order acceptance; however, to the best of our knowledge, this paper is the first research that integrates these essential decisions in the form of a mathematical model to maximize the total profit. The problem is NP-hard in nature; therefore, solving to optimality is not practically possible for problems with medium and large size. For that purpose, we developed a Heuristic Algorithm (HA) to solve the problem above in a reasonable time, with proper accuracy. Results from this heuristic algorithm are compared with that of a commercial solver (GAMS) and the well-known Genetic Algorithm (GA) and Variable Neighborhood Search (VNS). Computational experiments demonstrate that the developed heuristic algorithm is more efficient in comparison with other tested methods. 相似文献
109.
北海道では1980年代から2010年代まで,水稲圃場栽培期間である5–9月の気温は年代とともに上昇した。そこで,直近の2010年代(2010—2019年平均)と比べて, 2つの2030年代の予測気象から,既報の関係式より水稲生育を予測した。その結果,2030年代では2010年代に比べ,限界移植日(移植早限)が水稲栽培17地域の平均で8~9日早い。また,早限出穂期が1~5日早く,晩限出穂期が1~5日遅く,安全出穂期間が2~10日長い。出穂期は1~3日早い。出穂期から晩限出穂まで2~9日長いため,遅延型冷害の発生がやや少ない。生育期別気象は,出穂前24日以降30日間では生育が早いため平均気温が同じかやや低い。出穂前10日以降40日間および出穂期以降40日間では平均気温がやや高く,日射量はやや少ない。そのため,玄米収量は96~98%とやや低く,潜在収量性を示す気候登熟量示数は同じである。障害不稔発生に関係する穂ばらみ期冷害危険期の平均気温はわずかに低いかほぼ同じであるため,冷害発生の危険性は残る。一方,不稔発生をもたらす低温域の出現頻度には,地域間で差異がある。精米蛋白質含有率は同じであるが,アミロース含有率はやや低く,やや良食味である。米粒外観品質では被害粒歩合と着色粒歩合は一定の傾向がなく,未熟粒歩合はやや高い。精米白度は同じであるが,玄米白度はやや高い。以上の予測に対する技術的対応方向を示した。 相似文献
110.
凌亚文 《西安建筑科技大学学报(自然科学版)》1998,30(2):196-197
灵敏电流计内阻的测量结果误差较大,本文通过对一组实验数据分别用逐差法和最小二乘法进行计算,并用误差分析来说明,选择合适的数据处理方法,有助于获得正确的实验结果. 相似文献