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Due to its vegetative reproduction, saffron has a narrow genetic base and induced in vitro variations provide opportunities for expanding new cultivars. The objectives of this study were to evaluate sodium azide-induced variations in saffron’s corm culture in order to increase salt tolerance and pharmaceutical ingredients. Corm explants from the well-known ecotypes, Estahban and Kashmar, were subjected to various concentrations of sodium azide (NaN3) (0.09, 0.12, and 0.22 mg L?1) and NaCl (1.5, 2.5, and 4.0 dS equivalent to 0.07, 0.12, and 0.20 g NaCl in 100 mL water) in Murashige and Skoog medium supplemented with 1 mg L?1 2-4-D, 1 mg L?1 BAP, and 30 g L?1 sucrose and in a second pot culture experiment. The active pharmaceutical ingredients (crocin, picrocrocin, and safranal) were measured by high-performance liquid chromatography (HPLC). Variations in sodium azide-treated plants were more broadened for callus fresh weight (0.57–7.57 g), embryo weight (1.24–10.29 g), and regenerated seedlings (3.0–21.25) compared with those (0.12–3.77 g, 0.56–4.56 g, and 0.25–11.50, respectively) that were not treated with sodium azide. Under 0.20% salt, flowering failed in some of plants developed from sodium azide-untreated corms. HPLC analysis indicated wider ranges for crocin (11.92–18.03 mg g?1), picrocrocin (8.99–14.76 mg g?1), and safranal (2.13–7.36 mg g?1) in sodium azide-treated plants compared to the ranges (0.0–16.1, 0.0–12.5, and 0.0–6.66 mg g?1, respectively) in untreated plants. From a breeding perspective, induced variations found in this study would be useful to improve saffron’s quality and salt tolerance.  相似文献   
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We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentrations. We measured three wood anatomical traits, average vessel area(μm2), vessel number per square millimetre, and vessel lumen area percentage (%). For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar (p>0.05) incontrol and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seedlings, and the trend was more pronounced in treated seedlings. We conclude that vessel number per square millimetre in A. velutinum is influenced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can beused as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.  相似文献   
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Background:

This study was conducted to reveal that whether i.v. injection of oleuropein, the most potent polyphenolic antioxidant in olive leaf, has any effect on the magnitude of reperfusion arrhythmia in anesthetized rats or not.

Methods:

Eighty male Wistar rats were divided into 8 groups of 10 each: groups 1 and 5 were assigned as the prophylactic and treatment control groups, groups 2 and 6 as the prophylactic and treatment groups with lidocaine (10 mg/kg), groups 3 and 4 as the prophylactic groups with 10 and 50 mg/kg oleuropein (i.v.), and groups 7 and 8 as the treatment groups with 10 and 50 mg/kg oleuropein (i.v.), respectively. Reperfusion injury was induced by 5-min regional ischemia and 15-min reperfusion of left anterior descending coronary artery. Heart rate, blood pressure, and electrocardiogram were monitored throughout the procedure.

Results:

blood pressure was significantly decreased by infusion of 50 mg/kg oleuropein in groups 4 and 8, but unlike the lidocaine as a standard anti-arrhythmic drug in groups 2 and 5 had not significant effect on heart rate. The onset of arrhythmia in groups received oleuropein (groups 3, 4, 7, and 8) was significantly delayed. The mortality rate due to irreversible ventricular fibrillation was also significantly reduced in groups 3, 4, 7, and 8. The effect of lidocaine in groups 2 and 5 was more potent than that in oleuropein group.

Conclusion:

These findings indicate that i.v. injection of oleuropein possibly through its antioxidant activity reduces the magnitude of reperfusion-induced arrhythmia.Key Words: Oleuropein, Arrhythmia, Reperfusion, Rats  相似文献   
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An important feature of A. rhizogenes-induced hairy roots is their unique ability for investigation of gene function and production of secondary metabolites such as diosgenin in fenugreek. In order to evaluate the transformation frequency and the efficiency of transgenic hairy root induction, leaf and stem explants from two fenugreek ecotypes, Karaj and Bushehr, were infected with three concentrations of OD600= 0.8, 1.2, and 1.6 of A. rhizogenes strain K599 harboring a GFP gene. Regardless of ecotype, the ability of stem explants for the induction of hairy roots (8.09) and the transformation frequency (81.3%) was higher compared with leaf explants with the values of 5.97 and 71.88%, respectively. The number of transgenic GFP-positive hairy roots ranged from 4.2 to 13.5 in the Karaj ecotype and 3.8 to 9.9 in Bushehr. The highest transgenic hairy root (8.76), the transformation frequency (79.76%), and the growth rate of transgenic roots (0.77 d?1) were obtained from infection with K599 at OD600= 1.2, while the lowest belonged to the bacterial concentration of OD600=1.6. Although the ecotype Bushehr had lower total roots (7.53) and transgenic hairy roots (6.08), it showed higher transformation frequency (79.56%) than Karaj (73.63%). Therefore, the results indicate the importance of genotype, type of explant and bacterial concentration in breeding for induction of transgenic hairy roots and consequently, production of secondary metabolites in fenugreek.  相似文献   
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As a medicinal plant, the importance of evening primrose (Oenothera biennis L.) is due to its unsaturated fatty acids in the seeds and roots, and also oenotherine and comfarol in the leaves. Low germination and difficulties in seed production are the main problems encountered with growing this plant in the field. As an alternative approach, an in vitro experiment was set up for the evaluation of evening primrose production via direct and indirect regeneration of the cultivars NC-1 and VNK. For callogenesis and direct regeneration, the explants from the apical bud and petiole were cultured on MS medium supplemented with 0.25, 0.75, and 1.25 mg L?1 of both BAP and Kinetin (KIN). Indirect regeneration was performed by placing apical buds, petioles, and leaf explants on MS medium supplemented with 0.5 and 1 mg L?1 2,4-D and 0.5, 1, and 1.25 mg L?1 of both BAP and KIN. The highest shoot induction from direct regeneration was obtained with apical bud explants of VNK treated with 0.75 mg L?1 BAP. The highest callus weight (3.17 g) obtained from indirect regeneration was with petiole explants treated with 1 mg L?1 2, 4-D and 1 mg L?1 BAP in VNK cultivars. The highest number of torpedo embryogenic clusters (23.8) was obtained from the VNK petiole explants treated with 0.5 mg L?1 2, 4-D and 1.25 mg L?1 BAP. BAP had higher positive effects on in vitro production of evening primrose than KIN in both direct and indirect regeneration. In general, results indicated that VNK was more potent for regeneration than NC-1 and concentrations of 0.75 mg L?1 BAP for direct and 0.5 mg L?1 2, 4-D and 1.25 mg L?1of BAP for indirect regeneration had a higher efficiency for increasing in vitro production of evening primrose.  相似文献   
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The cover image is based on the Research Article Wolbachia promotes successful sex with siblings in the parasitoid Habrobracon hebetor by Zeynab Bagheri et al., https://doi.org/10.1002/ps.6649 .

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