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931.
Jay F. Bolin Kushan U. Tennakoon Mohamed Bin Abdul Majid Duncan D. Cameron 《Plant Species Biology》2017,32(1):74-80
The Burmanniaceae contain several lineages of achlorophyllous mycoheterotrophic plants that associate with arbuscular mycorrhizal fungi (AMF). Here we investigate the isotopic profile of a green and potentially mycoheterotrophic plant in situ, Burmannia coelestis, and associated reference plants. We generated δ 13C and δ 15N stable isotope profiles for five populations of B. coelestis. Burmannia coelestis was significantly enriched in 13C relative to surrounding C3 reference plants and significantly depleted in 13C relative to C4 reference plants. No significant differences were detected in 15N enrichment between B. coelestis and reference plants. The isotopic profiles measured are suggestive of partial mycoheterotrophy in B. coelestis. Within the genus Burmannia transitions to full mycoheterotrophy have occurred numerous times, suggesting that some green Burmannia species are likely to be partially mycoheterotrophic but in many conditions this mode of nutrition may only be detectable using natural abundance stable isotopic methods, such as when associated with C4 mycorrhizal plants. 相似文献
932.
Palliyath Sruthi Abdul Majeed Shackira Jos T. Puthur 《Wetlands Ecology and Management》2017,25(2):129-148
Heavy metals are among the major pollutants from anthropogenic inputs that reach mangrove ecosystem by urban and agricultural runoff, industrial effluents, boating, mining and other processes. To minimize the detrimental effects of heavy metal exposure and their accumulations, plants in general have evolved biological detoxification mechanisms, which include avoidance or exclusion, excretion and accumulation. To protect the cellular components from oxidative damage by heavy metal contamination, biological systems have developed enzymatic and non-enzymatic antioxidant mechanisms. Another detoxification mechanisms produced in plants are osmoprotectants, which are the compatible solutes which maintain a favourable water potential gradient and protect cellular structures from toxic ions. Besides these mechanisms, another heavy metal detoxification system in plants involves the chelation of metals by metal binding molecules like metallothioneins (MTs) and phytochelatins (PCs). To limit the heavy metal toxicity from mangrove ecosystem, it was found that phytoremediation is a most useful technology where in plants are used to remove pollutants from the environment and it is considered as a comparatively new, low-cost and highly promising technology for the remediation of heavy metal. Rhizofiltration, phytovolatilization, phytoextraction and phytostabilization are the important phytoremediation techniques. Among these phytoextraction and phytostabilization are found highly important in the case of mangroves and are promising means of phytoremediation. 相似文献
933.
Abdul Ahmad Siti Aisyah Uma D. Palanisamy Bimo A. Tejo Chew Miaw Fang Tham Hong Wai Syed Hassan Sharifah 《Virology journal》2017,14(1):229
Background
The rapid rise and spread in dengue cases, together with the unavailability of safe vaccines and effective antiviral drugs, warrant the need to discover and develop novel anti-dengue treatments. In this study the antiviral activity of geraniin, extracted from the rind of Nephelium lappaceum, against dengue virus type-2 (DENV-2) was investigated.Methods
Geraniin was prepared from Nephelium lappaceum rind by reverse phase C-18 column chromatography. Cytotoxicity of geraniin towards Vero cells was evaluated using MTT assay while IC50 value was determined by plaque reduction assay. The mode-of-action of geraniin was characterized using the virucidal, attachment, penetration and the time-of-addition assays’. Docking experiments with geraniin molecule and the DENV envelope (E) protein was also performed. Finally, recombinant E Domain III (rE-DIII) protein was produced to physiologically test the binding of geraniin to DENV-2 E-DIII protein, through ELISA competitive binding assay.Results
Cytotoxicity assay confirmed that geraniin was not toxic to Vero cells, even at the highest concentration tested. The compound exhibited DENV-2 plaque formation inhibition, with an IC50 of 1.75 μM. We further revealed that geraniin reduced viral infectivity and inhibited DENV-2 from attaching to the cells but had little effect on its penetration. Geraniin was observed to be most effective when added at the early stage of DENV-2 infection. Docking experiments showed that geraniin binds to DENV E protein, specifically at the DIII region, while the ELISA competitive binding assay confirmed geraniin’s interaction with rE-DIII with high affinity.Conclusions
Geraniin from the rind of Nephelium lappaceum has antiviral activity against DENV-2. It is postulated that the compound inhibits viral attachment by binding to the E-DIII protein and interferes with the initial cell-virus interaction. Our results demonstrate that geraniin has the potential to be developed into an effective antiviral treatment, particularly for early phase dengue viral infection.934.
935.
Ethnopharmacological studies of indigenous plants in Kel village,Neelum Valley,Azad Kashmir,Pakistan
Khawaja Shafique Ahmad Abdul Hamid Fahim Nawaz Mansoor Hameed Farooq Ahmad Jiabin Deng Noreen Akhtar Ambreen Wazarat Sehrish Mahroof 《Journal of ethnobiology and ethnomedicine》2017,13(1):68
Background
This explorative study was undertaken for the first time in Kel village located in the Upper Neelum Valley, Azad Kashmir, Pakistan. The purpose was to document the indigenous knowledge of the native people used in the preparation of herbal medicines.Methods
To get the data on traditional uses of medicinal plants, 20 informants were interviewed. Quantitative ethnobotanical indices, i.e., use value (UV), relative frequencies of citation (RFC), informant consensus factor (Fic), fidelity level (FL), data matrix ranking (DMR), preference ranking (PR), and jaccard index (JI), were calculated for the recorded medicinal plants.Results
A total of 50 medicinal plants belonging to 33 families used in 13 disease categories were documented. Leaves were the frequently used plant parts, and decoction was the commonly used method for herbal medicine. Plants with high use value were Berberis lycium (2.05), Impatiens glandulifera (1.95), Artemisia scoparia (1.75), Ageratum conozoides (1.75), and Achillea millefolium (1.7). The highest RFC value was calculated for Berberis lycium (0.75), Cynoglossum lanceolatum (0.65), and Impatiens glandulifera and Achillea millefolium (0.60 each). The maximum informant consensus factor was for urinary system, cardiac diseases, baldness, and abortion and miscarriage (1.00). Berberis lyceum (95%) used in jaundice, hepatitis, typhoid, fever, and tuberculosis disorders. Plants with maximum fidelity level (FL) were Berberis lycium (95%) followed by Dioscorea bulbifera, Impatiens glandulifera, and Artemisia vulgaris (90%). Olea ferruginea was the most multipurpose plant and exports (21.2%) was the leading threat in the area. The pearson correlation coefficient (0.500) showed a positive correlation between the use value and relative frequency of citation.Conclusion
The present study provides useful information about traditional uses of medicinal plants used by local communities in different ailments. The plants with the highest use values could be employed in pharmacological research and biotechnological approaches in order to achieve adequate revenue. Some of the plants in the study area are facing high threats of becoming rare, and conservation initiatives are needed to conserve them for sustainable management in the region.936.
Qurratu Aini Musthafa Muhd Faizan Abdul Shukor Noor Akmal Shareela Ismail Azmee Mohd Ghazi Rosli Mohd Ali Ika Faizura M. Nor 《Free radical research》2017,51(9-10):787-798
Identifying patients at risk of developing premature coronary artery disease (PCAD) which occurs at age below 45 years old and constitutes approximately 7–10% of coronary artery disease (CAD) worldwide remains a problem. Oxidative stress has been proposed as a crucial step in the early development of PCAD. This study was conducted to determine the oxidative status of PCAD in comparison to CAD patients. PCAD (<45 years old) and CAD (>60 years old) patients were recruited with age-matched controls (n?=?30, each group). DNA damage score, plasma malondialdehyde (MDA) and protein carbonyl content were measured for oxidative damage markers. Antioxidants such as erythrocyte glutathione (GSH), oxidised glutathione (GSSG), and glutathione peroxidase activity (GPx), superoxide dismutase (SOD) and catalase (CAT) were also determined. DNA damage score and protein carbonyl content were significantly higher in both PCAD and CAD when compared to age-matched controls while MDA level was increased only in PCAD (p<.05). In contrast, GSH, GSH/GSSG ratio, α-tocotrienol isomer, and GPx activity were significantly decreased, but only in PCAD when compared to age-matched controls. The decrease in GSH was associated with PCAD (OR?=?0.569 95%CI [0.375???0.864], p?=?.008) and cut-off values of 6.69?μM with areas under the ROC curves (AUROC) 95%CI: 0.88 [0.80–0.96] (sensitivity of 83.3%; specificity of 80%). However, there were no significant differences in SOD and CAT activities in all groups. A higher level of oxidative stress indicated by elevated MDA levels and low levels of GSH, α-tocotrienol and GPx activity in patients below 45 years old may play a role in the development of PCAD and has potential as biomarkers for PCAD. 相似文献
937.
938.
DNA barcoding of selected UAE medicinal plant species: a comparative assessment of herbarium and fresh samples 总被引:1,自引:0,他引:1
Mohamed Rizk Enan Abdul Rasheed Palakkott Taoufik Saleh Ksiksi 《Physiology and Molecular Biology of Plants》2017,23(1):221-227
It is commonly difficult to extract and amplify DNA from herbarium samples as they are old and preserved using different compounds. In addition, such samples are subjected to the accumulation of intrinsically produced plant substances over long periods (up to hundreds of years). DNA extraction from desert flora may pause added difficulties as many contain high levels of secondary metabolites. Herbarium samples from the Biology Department (UAE University) plant collection and fresh plant samples, collected from around Al-Ain (UAE), were used in this study. The three barcode loci for the coding genes matK, rbcL and rpoC1-were amplified. Our results showed that T. terresteris, H. robustum,T. pentandrus and Z. qatarense were amplified using all three primers for both fresh and herbaium samples. Both fresh and herbarium samples of C. comosum, however, were not amplified at all, using the three primers. Herbarium samples from A. javanica, C. imbricatum, T. aucherana and Z. simplex were not amplified with any of the three primers. For fresh samples 90, 90 and 80% of the samples were amplified using matK, rbcL and rpoC1, respectively. In short, fresh samples were significantly better amplified than those from herbarium sources, using the three primers. Both fresh and herbarium samples from one species (C. comosum), however, were not successfully amplified. It is also concluded that the rbcL regions showed real potentials to distinguish the UAE species under investigation into the appropriate family and genus. 相似文献
939.
Synthesis and study on the binding of thiazol‐2(3H)‐ylidine derivative with human serum albumin using spectroscopic and molecular docking methods
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In this article, a facile and convenient synthesis of thiazol‐2(3H)‐ylidine derivatives of fatty acid ( 3a – c ) is described. The binding of N′‐(4,5‐dimethyl‐3‐penylthiazol‐2(3H)‐ylidine)octadec‐9‐enehydrazide ( 3a ) with human serum albumin (HSA) is explored using various spectral methods and molecular docking. Fluorescence quenching results show that 3a induces conformational changes in HSA and the polarity around the tryptophan residues is increased. Stern–Volmer quenching plots at different temperatures (298, 305 and 312 K) show that the fluorescence quenching mechanism is static quenching. Synchronous fluorescence, 3D fluorescence spectra, circular dichroism and Fourier transform infrared spectroscopy are used to determine the structural change in HSA on interaction with 3a . Förster resonance energy transfer analysis shows that the binding distance (r0 = 2.78 nm) between HSA (Trp214) and 3a is within the of range 2–8 nm for quenching to occur. The molecular docking study also confirms that 3a is located in subdomain IIA (site I) of HSA and is stabilized by hydrogen bonding and hydrophobic forces. 相似文献
940.
Piritta Hynninen Jonna M H?m?l?inen Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S Sly Eija Tomas Pertti Kirkinen Seppo Parkkila 《Reproductive biology and endocrinology : RB&E》2004,2(1):73