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911.
Irfan Terzi Ismail Kocaçalişkan Osman Benlioğlu Kemal Solak 《Acta Physiologiae Plantarum》2003,25(4):353-356
Effects of juglone on seedling growth of cucumber (Cucumis sativus cv. Beith Alpha) with respect to physiological and anatomical parameters were investigated. Growth parameters (seedling elongation,
fresh and dry weights) were reduced by 1 mM juglone. Juglone also decreased chlorophyll a and b contents and reduced some
anatomical tissues (xylem vessel and bundle radius of stem, stomata length and stomata number of the cotyledons). The anatomical
changes in stem and cotyledon of the seedlings were related to growth inhibiting effect of juglone. On the other hand, increase
in catecholase and tyrosinase activities by the effect of juglone were also recorded. 相似文献
912.
Maryam Akram Maria Saleem Khan Sammia Shahid Hafiz Muhammad Abdur Rahman Iram Nadeem 《Bioscience, biotechnology, and biochemistry》2020,84(10):1967-1974
ABSTRACT This work presents the development and validation of a simple, rapid, and cost-effective spectrophotometric method for quantitative analysis of uric acid in biological samples. The method relies upon uric acid-led reduction of Fe(III) to Fe(II) of sample/standard solutions which stoichiometrically engages ferrozine to form a magenta-colored complex. Different parameters including pH, metal and chelator concentrations, temperature, etc., were optimized for the maximum intensity and stability of the complex. The uric acid concentrations of synthetic/plasma solutions were determined by comparing the color intensity of Fe(ferrozine)3 2+ complex produced by test solution with the standard curve formed by known uric acid concentrations. The method was validated in accordance with ICH guidelines and subjected to human plasma analysis. The results obtained were compared with a reference (enzymatic) method which revealed that there was no significant difference between the two methods at 95% confidence level. The method is highly specific, precise, linear, accurate, and robust. 相似文献
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Snehil Dixit Irfan Ahmad Kumar Gular Refaat A. Eid Ravi Shankar Reddy Ivana Leão Ribeiro Mohammed Abohashrh Mastour Saeed Alshahrani Jaya Shanker Tedla Nitin Arun Dixit 《Saudi Journal of Biological Sciences》2021,28(3):1678-1686
ObjectivesThe primary purpose of the recent experiment was to scrutinize the dissimilarity between single and multiple exposures by electrotherapeutic modalities to determine the development of Gram-positive and Gram negative bacteria spectrum.Material and methodsBacterial strains employed in this study were Gram-negative bacteria such as Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonae and Gram-positive bacteria such as Staphylococcus aureus, Staphylococcus saprophyticus and Streptococcus pyogenes. Fluence for Low level laser therapy (LLLT) (810 nm) was 40 J/cm2 for 80 s, for microwave (MWD) a dosage of 100-Watt with duration of 5 min and for magnetic field therapy (MT) duration of 30 min with 100% intensity was used.ResultsRepeated Measures of analysis of variances (RANOVA) for within-subject effects was used to detect a global significant change within the means at dissimilar time points. The experiments of within-subjects revealed a significant difference within groups, df of (3, 40), F value of 39.38 and a p value less than 0.001, representing a significant variation between the three groups between pre and post exposures. There was a significant variation between single exposure and multiple exposures in the experimental sample’s pre-post between the four groups with df (1, 40) f value of 2943.69 and p value less than 0.001. Scanning and Transmission electron microscopy images were also taken into account to determine the extent of damage caused to the bacterial cells surface topography in Gram negative and Gram positive spectrums.ConclusionThe study demonstrated that single high exposure with the LLLT appears to have the most emphatic effect followed by exposure by MWD and MT. 相似文献
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Ursolic acid (UA) is a ursane-type pentacyclic triterpenoid compound, naturally produced in plants via specialized metabolism and exhibits vast range of remarkable physiological activities and pharmacological manifestations. Owing to significant safety and efficacy in different medical conditions, UA may serve as a backbone to produce its derivatives with novel therapeutic functions. This review aims to provide ideas for exploring more diverse structures to improve UA pharmacological activity and increasing its biological yield to meet the industrial requirements by systematically reviewing the current research progress of UA. We first provides an overview of the pharmacological activities, acquisition methods and structural modifications of UA. Among them, we focused on the synthetic modifications of UA to yield valuable derivatives with enhanced therapeutic potential. Furthermore, harnessing the essential advances for green synthesis of UA and its derivatives by advent of metabolic engineering and synthetic biology are of great concern. In this regard, all pivotal advances for enhancing the production of UA have been discussed. In combination with the advantages of UA biosynthesis and transformation strategy, large-scale microbial production of UA is a promising platform for further exploration. 相似文献
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Aasim Muhammad Ali Seyid Amjad Bekiş Pınar Nadeem Muhammad Azhar 《In vitro cellular & developmental biology. Plant》2022,58(5):816-825
In Vitro Cellular & Developmental Biology - Plant - Optimization of in vitro regeneration protocol using multiple input variables is highly significant, and can be achieved by validating the... 相似文献