الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was carried out to evaluate the impact of irrigation with two different concentrations of seawater; (50 mM) and (150 mM) (as a source of salinity stress) and (125 mM) of mannitol as osmoprotectant on some physiological and phytochemical parameters of Anastatica hierochuntica . plant (Kaff maryum). Also to improve plant performance and production of phytochemicals, in particular flavonoids. 1- Physiological results Percentages of germination The present results showed that there is a negative correlation between the concentrations of seawater and the percentage of germination as being compared to the control Also, such reduction in percentage of germination is recorded in case of mannitol alone and mannitol in combination with salinity. Growth at the vegetative stage There are significant decreases in the shoot length for all treatments except the low concentration of salinity (50 mM) which gives significant increase as being compared to the control In addition, mannitol alone induced a significant reduction in shoot length and non significant reductions in combination with both low and high salinity concentrations (MS1 and MS2). In contrast, the root length showed significant increments in response to both salinity treatments (50 mM and150 mM). Both salinity concentrations (50 and 150 mM) increased the fresh and dry weights of A. hierochuntica . In contrast, mannitol alone and in combination with (150 mM) reduced both the fresh and dry weights respectively. It is obvious that there is a positive correlation between the number of branches and leaves number and this correlation is concurrent with increase in the leaf area in response to both the low and high concentrations of seawater as compared to the control. In addition, mannitol interaction with the low saline solution (50 mM) showed no change in both the branches number and leaves number, while the leaf area was reduced as being compared to the control. Growth at the yield stage It is obvious from the results that only S1 treatment (50 mM) saline solution induced shoot length as being compared to the control. Both the low and high concentrations of saline solution had stimulatory effect on the root length, while mannitol alone or in combination with the high concentrations (150 mM) had inhibitory effects. Application of saline solution at the low and high concentrations (50 and 150 mM) induced significant increments in both the fresh and dry weights of A. hierochuntica plants. Mannitol in combination with (150 mM) significantly reduced the fresh weight and non siginificantly reduced the dry weight. Regarding the number of branches and fruits per plants, it is evident that the number of branches A. hierochuntica increased in response to both salinity treatments alone (50 mM and 150 mM) or in combination with mannitol (MS1 and MS2) and this was concurrently followed by increments in the number of fruits per plant. In contrast, mannitol treatment alone decreased both the number of branches and fruits per plant. Changes in metabolites Changes in photosynthetic pigment The results showed significant increments in chlorophyll a ,chlorophyll b and carotenoids in response to the treatment with the low concentration of seawater alone (50 mM) or in combination with mannitol as being compared to the control . Concerning the higher concentration of seawater (150 mM), itshowed two different trends for being alone or in combination with mannitol. Changes in carbohydrate contents The results showed significant increments in all sugar contents in response to the treatment with the lower concentration of seawater alone (50 mM) or in combination to mannitol as being compared to the control. The high concentration (150 mM) accumulated the highest amount of polysaccharides in the shoot system. Changes in Antioxidant Compounds Proline showed high significant increments in all treatments as being compared to the control. The lowest proline content was under mannitol. Anthocyanin contents were significantly increased under both seawater and/or mannitol treatments, the control plants have the least amount than all treatments. Vitamin E content It is clearly shown that irrigation with (50 mM) of seawater either alone or in combination with mannitol had significant increases. On the other hand, the higher concentration (150 mM) decreased vitamin E content.Total phenolic Concerning the total phenol contents, it is clearly shown that all treatments significantly increased these contents as being compared to the control. It is noticeable that the total phenolics contents increased by increasing the concentration from the lower concentration (50 mM) to the higher one (150 mM), Also the above contents showed the highest values at mannitol interaction with both the concentrations especially the high one (150 mM).It is also clear that the vegetative stage is more rich in the phenolic contents than the yield stage. Total flavonoids The total flavonoid contents mostly showed the same pattern as that of total phenolics, it is also important to mention here that there is a strong positive correlation between the total phenolices and total falvonoids contents. Moreover, the accumulation of flavonoid compounds was attributed to an increase in the level of the major compounds; kaempferol 3-O-β-glucopyranoside, quercetin and quercetin 3-O-β-glucopyranoside. Antioxidant activity It is evident from the antioxidant activity increased by increasing the total phenolics and flavonoid contents.Changes in the protein profile There are some qualitative changes which include the disappearance and appearance of de novo synthesized bands. The disappeared bands are 114 kDa in mannitol interaction with both 50 mM and 150 mM and 37 kDa in S2 and M .Six de novo synthesized bands are 97 kDa, 64 kDa, 40 kDa, 33 kDa, 22 kDa and 14 kDa. but 97 kDa appeared in MS2 only, 64k Da in MS1, 40k Da in all treatments, 33 kDa in S1 and S2, 22 kDa in M only and finally 14kDa in all treatments. 2-Phytochemical analysis Quantitative estimation of flavonoids at the vegetative stage It is clearly shown from the present work that twelve flavnoid compounds were separated from A. heriochuntica. in relation to the effect of seawater, mannitol and their interaction. All treatments had great amounts of the separated flavonids as being compared to the control. Moreover, the increase in levels of these three compounde reflected the change in total phenolic content and flavonoid compounds. they were Kaempeferol 3-O- -rutinoside, Quercetin, and Quercetin 3-O--glucopyranoside. Five Compounds were isolated for the first time from A. hierochuntica. The extracts of control C, include flavonoids (1-12) and the five treatments (S1, S2, M, MS1 and MS2) were subjected to HPLC analysis as well as CO-PC with authentic samples using two dimension paper chromatography (2D-PC). Twelve flavonoid compounds were isolated and identified from the control extract of A. hierochuntica (vegetative stage).They were identified as apigenin (1), luteolin 7-O-β- glucopyranoside (2), luteolin 7-O--glucronoide (3), kaempferol 3-O-β-glucopyranoside(4),quercetin (5), quercetin 3-O-β- glucopyranoside(6), quercetin 3-O-rutinoside (Rutin) (7), apigenin 6-C--glucopyranoside [isovitexin] (8), apigenin 6C-α- arabinopyranoside8-C--glucopyranoside (9), luteolin 6-C-- glucopyranoside [isoorientin] (10), luteolin 8-C-- glucopyranoside [orientin] (11) and naringenin(12). In conclusion, the results of the thesis in hands demonstrated that the present treatments may signify an effective tool to induce the phenolic contents, flavonoid compounds as well as the antioxidant activity of Kaff maryum. The highest yield of previous metabolites was obtained after two months of cultivation; therefore, the harvest of the plant is recommended in the vegetative stage. |