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111.
Heavy metal-polluted water has become a problem for sustainable environment, agriculture, and human health. Phyto-accumulation is an eco-friendly technique for decontamination of metal-polluted water and soil. The efficiency of phyto-accumulation and rhizo-filtration can be enhanced by the application of certain nutrients to accumulator plants. In this study, we focused on the role of iron (Fe) in rhizo-filtration and phyto-accumulation of cadmium (Cd) from polluted water/media, using Ricinus communis plant. Medium was contaminated with 10 ppm Cd while Fe (2.50, 5.00, and 7.50 ppm) was applied both as foliar spray and medium addition separately. Accumulation of Cd and concentrations of soluble proline, phenolic compounds, and chlorophylls were measured in plant tissues. Addition of Fe into media significantly increased biomass in the plants but decreased Cd absorption by roots and its accumulation in other tissues of the plants. Foliar application of Fe, especially 7.5 ppm, significantly increased biomass as well as accumulation of Cd in tissues of the plants. Contents of soluble proline (41.88?±?3.56 ppm) and phenolics (171.00?±?4.98 ppm) in leaves were highly increased by foliar spray of 7.5 ppm Fe on the plants. On the other hand, highest concentrations of free proline (67.00?±?2.00 ppm) and total phenolics (82.67?±?2.52 ppm) in plant roots were observed in 7.5 ppm Fe added to media and as foliar spray, respectively. Strong correlations were observed between phenolics content in roots and leaves with Cd accumulation after foliar application of 7.5 ppm Fe. 相似文献
112.
Two experiments were conducted to evaluate the effects of dose and timing of silicon (Si) application on rice under limited water supply. The treatments for the first study included five Si doses (0, 75, 150, 300 and 600 kg Si ha–1) under three soil moisture conditions (100%, 75% and 50% field capacity). For the second study, the treatments were four Si application timings [100% basal, 50% basal + 50% panicle initiation (PI), 25% basal + 75% PI and 25% basal + 50% PI + 25% heading] at the dose of 300 kg ha–1 under the same moisture conditions. The highest number of panicle plant–1 (14.6) and grain yield (13.6 g plant–1) were obtained with the dose of 300 kg Si ha–1. Similarly, an increase of 34–45% in grain yield was observed for different Si application timings compared with the control. Shoot dry matter and grain yield had positive linear relationship with shoot Si content. Grain yield and number of spikelet panicle–1 were higher at the 300 kg Si ha–1 dose applied as 100% basal, and hence could be a feasible option for RD57 Thai rice variety under water-deficit conditions. 相似文献
113.
Md. Rezaul Karim Sheikh A. Nayeem Farouqui Rosiyah Yahya Aziz Hassan 《Fibers and Polymers》2011,12(5):642-647
In this paper, Rajshahi silk fabric was modified by acetic acid, tannic acid and their mixture. After acid modification, the
silk fabric was dyed with three dyes classes namely: Reactive Orange 14, Direct Yellow 29 and Mordant Blue 9. Results revealed
that the fabric modified with acid mixture of 30 % acetic acid and 20 % tannic acid improved the colorfastness of the dyed
fabric after 7 days exposure on simulated sunlight and washing with hot soap solution. Also, the acid modification could improve
the dyed fabrics’ colorfastness properties to acids and alkalis. Optimum dyeing condition was observed at 1.5, 2.0, and 2.0
% dyes for Reactive Orange 14, Direct Yellow 29 and Mordant Blue 9 respectively. The optimum dyeing time was observed 50,
60, and 50 min; and temperature was 90, 100 and 80 °C respectively. Modification of silk fabrics with acids improves the dyeability
and colorfastness of Rajshahi silk fabrics. However, the acid modification could reduce the loss in tenacity of silk fabric
upon exposure to sunlight. 相似文献
114.
Mohamed Elamir F. Hegazy Tarik A. Mohamed Montaser A. Alhammady Alaa M. Shaheen Eman H. Reda Abdelsamed I. Elshamy Mina Aziz Paul W. Paré 《Marine drugs》2015,13(5):3154-3181
Marine invertebrates including sponges, soft coral, tunicates, mollusks and bryozoan have proved to be a prolific source of bioactive natural products. Among marine-derived metabolites, terpenoids have provided a vast array of molecular architectures. These isoprenoid-derived metabolites also exhibit highly specialized biological activities ranging from nerve regeneration to blood-sugar regulation. As a result, intense research activity has been devoted to characterizing invertebrate terpenes from both a chemical and biological standpoint. This review focuses on the chemistry and biology of terpene metabolites isolated from the Red Sea ecosystem, a unique marine biome with one of the highest levels of biodiversity and specifically rich in invertebrate species. 相似文献
115.
John Yew Huat Tang Farinazleen Mohamad Ghazali Abdul Aziz Saleha Yoshitsugu Nakaguchi Mitsuaki Nishibuchi Son Radu 《Frontiers of Agriculture in China》2010,4(4):501-506
The goal of this study is to enumerate Campylobacter in chicken meats and by-products. In the current investigation, results showed that raw chicken meats and chicken by-products
were contaminated with Campylobacter ranging from <3 to 4600 MPN·g−1. Campylobacter jejuni showed a higher number compared to Campylobacter coli in the chicken samples. The current study showed that the percentage of chicken livers and gizzards harbored a higher number
of Campylobacter (103–104 MPN·g−1) than other chicken parts at 33.3% and 9.2%, respectively. The different concentrations of Campylobacter between chicken meats and chicken byproducts reflect the differences in the contamination level. The data on Campylobacter concentration in chicken meats and by-products will be useful in risk analysis. 相似文献
116.
Ullah AH Sethumadhavan K Mullaney EJ 《Journal of agricultural and food chemistry》2008,56(9):3398-3402
The pH profiles of two microbial phytases were determined using four different general purpose buffers at different pH values. The roles of calcium chloride, sodium chloride, and sodium fluoride on activity were compared in these buffers. For Aspergillus niger phytase, calcium extended the pH range to 8.0. A high concentration of sodium chloride affected the activity of fungal phytase in the pH 3-4 range and shifted the pH optimum to 2.0 from 5.5 in Escherichia coli phytase. As expected, both of the microbial phytases were inhibited by sodium fluoride at acidic pH values. Because the Km for phytate increased nearly 2-fold for fungal phytase while Vmax increased about 75% in a high concentration of sodium chloride, it is possible that salt enhanced the product to dissociate from the active site due to an altered electrostatic environment. Modeling studies indicate that while the active site octapeptide's orientation is very similar, there are some differences in the arrangements of alpha-helices, beta-sheets, and coils that could account for the observed catalytic and salt effect differences. 相似文献
117.
Detection of Diarrheic Shellfish Poisoning and Azaspiracid Toxins in Moroccan Mussels: Comparison of the LC-MS Method with the Commercial Immunoassay Kit 总被引:1,自引:0,他引:1
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Diarrheic shellfish poisoning (DSP) is a recurrent gastrointestinal illness in Morocco, resulting from consumption of contaminated shellfish. In order to develop a rapid and reliable technique for toxins detection, we have compared the results obtained by a commercial immunoassay-“DSP-Check” kit” with those obtained by LC-MS. Both techniques are capable of detecting the toxins in the whole flesh extract which was subjected to prior alkaline hydrolysis in order to detect simultaneously the esterified and non esterified toxin forms. The LC-MS method was found to be able to detect a high level of okadaic acid (OA), low level of dinophysistoxin-2 (DTX2), and surprisingly, traces of azaspiracids 2 (AZA2) in mussels. This is the first report of a survey carried out for azaspiracid (AZP) contamination of shellfish harvested in the coastal areas of Morocco. The “DSP-Check” kit was found to detect quantitatively DSP toxins in all contaminated samples containing only OA, provided that the parent toxins were within the range of detection and was not in an ester form. A good correlation was observed between the two methods when appropriate dilutions were performed. The immunoassay kit appeared to be more sensitive, specific and faster than LC-MS for determination of DSP in total shellfish extract. 相似文献
118.
为了深入了解斑马鱼端脑的微细形态和超微结构,采用光镜和电镜技术对斑马鱼端脑进行观察研究。斑马鱼端脑由左、右嗅球和左、右大脑半球构成。嗅球前方有一对嗅神经,后端伸出嗅茎与大脑半球联系。光镜下,嗅球组织结构从外向内依次为上皮层、神经纤维层、小细胞层和内部细胞层。大脑半球外部覆盖很薄的大脑皮,基部为纹状体,两者之间的腔隙为公共脑室。纹状体由神经核团和神经纤维构成。神经核团分布于纹状体周缘,主要有连前核、背嗅核、侧嗅核、视前核和脚内核等。神经纤维包括横行的前连合,纵行和斜行的中央嗅束和侧嗅束。电镜下,嗅球分层明显,可观察到僧帽细胞、神经胶质细胞和众多突触。大脑半球中可见神经胶质细胞、突触以及血脑屏障系统等。斑马鱼端脑形态结构与大多数硬骨鱼相似,但有个别核团存在差异。实验结果可为斑马鱼神经生物学模型的建立与应用提供有效的理论基础。 相似文献
119.
Kifayat?Ullah?KhanEmail authorView authors OrcID profile Amina?Zuberi Jo?o?Batista?Kochenborger?Fernandes Imdad?Ullah Huda?Sarwar 《Fish physiology and biochemistry》2017,43(6):1689-1705
In the present review, the ongoing researches about selenium research in fish nutrition have been comprehensively discussed. Selenium research is getting popularity in fish nutrition as it is required for the normal growth and proper physiological and biochemical functions in fish. Its deficiency or surplus amounts create severe problems in fish. It is available as inorganic form, organic form, and nano form. In fish, most of the previous research is about the selenium requirements for fish by using only one selenium source mainly the inorganic one. Selenium shows maximum biological activity and bioavailability when it is supplied in proper form. However, to differentiate the more bioavailable and less toxic form of selenium, sufficient information is needed about the comparative bioavailability of different selenium forms in different fish species. In fish, important data about the new forms of selenoproteins is still scarce. Therefore, it is necessary to focus on the determination and elucidation of the new selenoproteins in fish through the utilization of recent approaches of molecular biology and proteomics. The adaptation of these new approaches will replace the old fashioned methodologies regarding the selenium research in fish nutrition. Moreover, the use of molecular biology and proteomics-based new approaches in combination with selenium research will help in optimizing the area of fish nutrition and will improve the feed intake, growth performance, and more importantly the flesh quality which has a promising importance in the consumer market. 相似文献
120.
Mohammed Mitache Aziz Baidani Chafika Houasli Khadija Khouakhi Bouchaib Bencharki Omar Idrissi 《Plant Breeding》2023,142(4):463-476
The use of high-performing varieties could contribute to increase food legume production and meet the population demand. However, the long process of conventional breeding is a serious limitation that needs further acceleration of genetic improvement. Speed breeding based on extended photoperiod is one of the techniques that allows rapid generation turnover by accelerating the plant life cycle. The present study focused on optimizing the duration of extended photoperiod for lentil, chickpea and faba bean in a growth chamber with light-emitting diode (LED) light sources. Significant differences in growth rate, biomass production, phenology, physiology, plant injury and yield components were observed depending on light phase durations (22, 18 and 14 h). Twenty-two hours of light resulted in earlier flowering and maturity, but higher stress symptoms than the other two light treatments. However, vegetative development was almost normal with limited stress under 14 h of light, but late flowering and maturity. Interestingly, good plant establishment with limited stress and shorter vegetative cycle was observed under 18 h of light. Therefore, a photoperiod of 18 h of light/6 h of darkness could be advised for a rapid breeding protocol. 相似文献