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31.
To investigate the salt tolerance mechanisms, Aeluropus lagopoides as a halophytic plant was used. Plants were treated with 0, 150, 450, 600, and 750 mM NaCl and harvested at 0, 4, 8, and 10 days after treatment and 1 day and 1 week after recovery. Optimal growth, measured as fresh and dry weights, occurred at 150 mM NaCl, but it was suppressed by 450, 600, and 750 mM NaCl. Recovery significantly increased fresh and dry weights only in 750 mM NaCl-treated plants. Water content was decreased after NaCl treatment and increased after recovery. Na+ and proline contents and activity of superoxide dismutase (SOD) were increased after NaCl treatment and decreased after recovery in all treated plants. In contrast, K+ content and ascorbate peroxidase activity decreased after NaCl treatment and increased after recovery in all treated plants. Catalase (CAT) was activated only in 750 mM NaCl-treated plants. Total content of soluble protein was slightly changed after NaCl treatment. It was concluded that proline accumulation for osmotic adjustment, SOD activation for O2·− scavenging, and CAT activation at the higher level of salt stress to detoxify produced H2O2 were main A. lagopoides strategies under salt stress. A. lagopoides salt tolerance was not based on the restriction of Na+ uptake.  相似文献   
32.
Steroidal sapogenins and phytosterols are a group of secondary metabolites which are very considerable in the pharmaceutical industry. Fenugreek (Trigonella foenum-graecum L.) is the good source of these compounds. In recent decades, there is a great interest to production of these compounds by cultivation of transformed roots. In present study, hairy roots induction in two Trigonella species (T. foenum-graeceum, T. monantha) with three strains of Agrobacterium rhizogenes (15,834, A4 and wt) was investigated. Transgenic status of roots was confirmed by PCR using rolB specific primers. Virulence of these strains was examined on explants of leaf, leaf cotyledone and hypocotyle in both species. The best strain was wt for hairy root induction in hypocotyle and leaf explants of T. foenum-graeceum and T. monantha. Significant quantitative differences were showed between shoot, root and hairy roots in both species. Protein content in root and hairy root of both species was significantly lower in comparison with shoot. Superoxide dismutase (SOD) and peroxidase (POX) activities in hairy roots of both species were higher as compared to other organs. The hairy roots of both species showed an ability to synthesize steroidal sapogenins. These results presented that hairy roots could be a suitable procedure for producing sapogenins compounds that have medicinal value in Trigonella.  相似文献   
33.
The objective of the present work was to study biochemical alterations in lime plants infected by the Candidatus Phytoplasma aurantifoliae. Changes in antioxidant activities, content of chlorophylls (Chl), carotenoids (Car), soluble proteins, sugars and auxin (IAA) in infected plant were investigated. The activities of polyphenol oxidase (PPO), peroxidase (POX) and superoxide dismutase (SOD) were observed to be greater in infected leaves than the healthy control. Also according to non-denaturing PAGE, in infected leaves all the antioxidative enzymes isoforms were stronger than that of the healthy control. These results suggest that antioxidant enzymes can be activated in response to infection by phytoplasma. The decrease in content of proteins, total soluble and reducing sugars in infected plants point out changes in host metabolism due to the phytoplasma infection. The reduction in chlorophylls and auxin content shows that the phytoplasma can interfere in photosynthesis and induces senescence in the leaf. In conclusion, this study provides new insights into the lime response to phytoplasma infection.  相似文献   
34.
Various plant oils (50 g l–1) increased the production of erythromycin by Saccharopolyspora erythraea. Maximum titer of erythromycin in media containing black cherry kernel, walnut, rapeseed, olive and cottonseed oils and control medium were 3.5, 2.8, 2.6, 2.1, 1.9, 0.7 g l–1, respectively. Erythromycin production media containing rapeseed or cottonseed oil was growth-dependent but not in other media used.  相似文献   
35.
Effect of high-frequency vibration on growth rate, membrane stability and activities of some antioxidant enzymes were studied in callus tissues of Hyoscyamus kurdicus. Calli initiated from leaf (LE), shoot (SE) and root (RE) explants, and sinusoidal vibrations at 0, 50, 100 and 150 Hz for 30 min were applied on the H. kurdicus calli. Results showed that sinusoidal vibration at 50 and 100 Hz promoted the growth rate as compared to control, and the optimum growth was found at 50 Hz. Sinusoidal vibration increased significantly protein and proline contents and activity of superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POX) enzymes, and decreased total carbohydrate, H2O2 level and CAT activity as compared to control. Lipid peroxidation also decreased under sinusoidal vibration in all the calli, and the maximum percentage of decrease was observed at 50 Hz. Native polyacrylamide gel electrophoresis indicated different isoform profiles in vibration treated and untreated plants concerning antioxidant enzymes. The responses of different types of calluses were different, and RE callus showed the highest growth, membrane stability and antioxidant enzymes activity as compared to LE and SE calli. These results suggest sinusoidal vibration at optimum frequency could improve callus growth by induction of antioxidative enzymes activity and membrane stability in calli of H. kurdicus.  相似文献   
36.
Russian Journal of Plant Physiology - During the evolutionary process, all living cells experience natural magnetic fields (geo-magnetic fields) as a usual part of their environment. Living...  相似文献   
37.

Purpose

To determine whether 5-methylenetetrahydrofolate (MTHF) is more effective than folic acid supplementation in treatment of recurrent abortion in different MTHFR gene C677T and A1298C polymorphisms.

Methods

A randomized, double blind, placebo-controlled trial conducted April 2011-September 2014 in recurrent abortion clinics in Tehran, Iran. The participants were women with three or more idiopathic recurrent abortion, aged 20 to 45 years. Two hundred and twenty eligible women who consented to participate were randomly assigned to receive either folic acid or 5-MTHF according to the stratified blocked randomization by age and the number of previous abortions. Participants took daily 1 mg 5-methylentetrahydrofolate or 1 mg folic acid from at least 8 weeks before conception to the 20th week of the pregnancy. The primary outcome was ongoing pregnancy rate at 20th week of pregnancy, and the secondary outcomes were serum folate and homocysteine at the baseline, after 8 weeks, and at the gestational age of 4, 8, 12, and 20 weeks, MTHFR gene C677T and A1298C polymorphisms.

Results

There was no significant difference in abortion rate between two groups. Serum folate increased significantly in both groups over time; these changes were significantly higher in the group receiving 5-MTHF than the group receiving folic acid (value = 2.39, p<00.1) and the result was the same by considering the time (value = 1.24, p<0.01). Plasma tHcys decreased significantly in both groups over time; however these changes were not significantly different between the groups (value = 0.01, p = 0.47).

Conclusion

The results do not support any beneficial effect of 5-MTHF vs. folate supplementation in women with recurrent abortion with any MTHFR C677T and/or A1298C polymorphism.

Trial Registration

ClinicalTrials.gov NCT01976676  相似文献   
38.
In Vitro Cellular & Developmental Biology - Plant - Effect of sinusoidal vibration on the activity of some antioxidative enzymes, pigments, membrane stability, and total phenolic was...  相似文献   
39.
40.
Longidorus kheirii n. sp., a parthenogenetic species, was found in soil samples collected from the rhizosphere of Rosa sp. growing in a natural mountainous region close to Maragheh city, northwestern Iran. It is characterised by having a long body (6.7-9 mm), a 19.5-23 mum wide head continuous with the body contour, a truncate and slightly concave lip region with convex sides between the anterior end and the guide-ring, an odontostyle 113-130 mum long, an odontophore 69-97.5 mum long, a body width of 90.5-117.5 mum at the mid-body, a long, wide oesophageal bulb (149.5-193.5 x 39.5-48 mum), a tail length of 47-72 mum, a male with 11 ventromedian supplements and spicules of 85 mum in length, and four juvenile stages. The ribosomal 18S rDNA gene of L. kheirii n. sp., L. leptocephalus Hooper, 1961, L. profundorum Hooper, 1966 L. euonymus Mali & Hooper, 1973 and two unidentified species listed as Longidorus sp. 1 and Longidorus sp. 2, all recovered from northwestern Iran in the same survey, and the ITS1 of L. kheirii n. sp. and Longidorus sp. 1 were sequenced in order to investigate the phylogenetic relationships with other previously sequenced Longidorus species.  相似文献   
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