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Influence of NaCl salinity on growth analysis of strawberry cv. camarosa

Influence of NaCl salinity on growth analysis of strawberry cv. camarosa

Rahimi Asghar, Biglarifard A., Mirdehghan H., Borghei S.F.

Статья научная

In order to study of salinity effect on growth analysis of strawberry, a greenhouse experiment was conducted in Vali-e-Asr University of Rafsanjan in 2010. This study was carried out RCBD design with 4 replications to determine the influence of salinity (30, 60, 90 Mmol and control with distilled water) on strawberry growth analysis. Results indicated that relative growth rate (RGR), crop growth rate (CGR), leaf area ratio (LAR) and dry matter accumulation were decreased with increasing salinity. The lowest RGR, CGR and LAR were observed in 90 Mmol NaCl salinity. Results also indicated that maximum dry matter accumulations were observed in 1050, 1200 and 1400 degree days in 30, 60 and 90 Mmol NaCl salinity, respectively. Water salinity more than 30 Mmol NaCl L-1 will decreased fresh fruit yield more than 50 percent in hydroponics strawberry production. Dry mass partitioning in NaCl-stressed plants was in favor of crown and petioles and at expense of root, stem and leaf whereas leaf, stem and root DM progressively declined with an increase in salinity.

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Influence of Nitrogen and Carbon Sources on Twitching-Mediated Motility of Lysobacter antibioticus Hz25

Influence of Nitrogen and Carbon Sources on Twitching-Mediated Motility of Lysobacter antibioticus Hz25

Yuliya V. Nurminskaya, Yuliya A. Markova

Статья научная

Predatory bacteria of the genus Lysobacter are known to utilize type IV pili for substrate translocation (twitching motility); however, the ecological signals regulating the transition to the motile state in Lysobacter remain insufficiently studied. Using the strain Lysobacter antibioticus Hz25, isolated from the rhizosphere of the Baikal endemic Hedysarum zundukii Peschkova, as a model, we investigated the effects of organic nitrogen content, carbohydrate type, and prey proximity on type IV pili-mediated motility. Motility of Hz25 was observed only in the presence of organic nitrogen: within the range of 1–5 g/L yeast extract, the colony front migration speed increased from 15 to 42 µm/h. On media without organic nitrogen (with NH₄Cl), no motility was induced. At 5 g/L yeast extract, replacement of sucrose (10 g/L) with maltose or trehalose increased the speed to 46–57 µm/h; replacement with fructose reduced it to <10 µm/h. Upon contact with live prey cells (Sinorhizobium sp., Planococcus sp.) in the V-test (5 g/L yeast extract, 10 g/L sucrose), the predator migration speed along the prey imprint reached approximately 420 µm/h. Directed migration of Hz25 toward prey from a distance of 30 mm was demonstrated. The speed in this experiment also depended on the sugar type and was maximal on trehalose- and maltose-containing media. These findings suggest that organic nitrogen acts as a key factor triggering twitching motility in Hz25, while the carbohydrate type may serve as a speed modulator. This indicates a multi-level regulation of predatory motility in Hz25. This work contributes to understanding the ecological regulation of type IV pili-mediated motility in the genus Lysobacter.

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Influence of PGR on the Concentration of Potassium, Magnesium, and Calcium in Simarouba glauca DC. Under Water Stress

Influence of PGR on the Concentration of Potassium, Magnesium, and Calcium in Simarouba glauca DC. Under Water Stress

P.D. Awate, M.S. Patil, Chirag Narayankar, D.K. Gaikwad

Статья научная

The present study aimed to examine the impact of different Plant growth regulators (PGRs)such as 50 ppm Salicylic Acid (SA), 10 ppm Putrescine, Gamma-Aminobutyric Acid (GABA), and Abscisic Acid (ABA) on the levels of potassium, magnesium, and calcium in the medicinally important, oil-yielding plant Simarouba glauca DC. under water stress conditions. One year old Simarouba glauca seedlings were subjected to water stress for 4, 8, 12, and 16 days. It was observed that water stress led to a decrease in the potassium, magnesium, and calcium content in the roots, stems, and leaves of S. glauca compared to the unstressed control. However, foliar application of ABA, SA, Putrescine, and GABA resulted in an increase in the potassium, magnesium, and calcium content in the stressed plants. Specifically, SA, Putrescine, and GABA treatments induced the accumulation of potassium. These results suggest that SA, Putrescine, GABA, and ABA play vital roles in enhancing drought tolerance in Simarouba glauca by modulating the accumulation of key minerals under water stress conditions.

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Influence of aqueous extracts of Nauclea latifolia on serum biomarker enzymes of liver injury and serum electrolytes in streptozotocin-induced diabetic Wistar albino rats

Influence of aqueous extracts of Nauclea latifolia on serum biomarker enzymes of liver injury and serum electrolytes in streptozotocin-induced diabetic Wistar albino rats

Ochalefu D.O., Adoga G.I., Luka C.D., Abu A.H., Myke-mbata B.K., Mfaga I.C.

Статья научная

Background. The management of diabetes mellitus and its complications is increasingly becoming difficult as new type and subtypes are being discovered. There is, therefore, a continuous search for more effective drug agents for its management. In this work the aqueous extracts of leaves, stem-bark and root-bark of Nauclea latifolia were investigated for their effects on serum liver enzymes and serum electrolytes in streptozotocin- induced diabetic Wistar albino rats. Serum levels of aspartate aminotransferase and alanine aminotransferase were determined using assay kits (Randox laboratories, LTD, UK). Alkaline phosphatase level was estimated using kits from Teco Diagnostic Anaheim, United States of America. The electrolytes were analysed using Ion Selective Electrode (ISE) Automated Analyser Machine (SFRI, 3000 model). Results. The results showed significant reduction (p

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Influence of chlorpyrifos stress on protein metabolism of edible crab Barytelphusa guerini, and its recovery

Influence of chlorpyrifos stress on protein metabolism of edible crab Barytelphusa guerini, and its recovery

Narra Madhusudan Reddy, Regatte Rudra Reddy, Kodimyala Rajender

Статья научная

The sublethal stress of chlorpyrifos on important metabolites and enzymes of protein metabolism was investigated in most important tissues (gills, muscle, hepatopancreas and nervous tissue) of freshwater edible crab, Barytelphusa guerini. The crabs were exposed to 0.07 mg/l (1/3 of LC 50) for 7, 14, 21 and 28 days. After 28 days of exposure, they were released into fresh water and kept in the same for 21 days in order to study recovery (3days interval). Total protein content was decreased where as amino acids and ammonia was increased. After cessation of intoxication recovery was observed. Urea content was decrease in all tissues and glutamine exhibited mixed response and recovery was highest in muscle. The activities of protease and aminotransferases were elevated in tissues for 28 days. Recovery of these enzymes activities was noticed during depuration. Acid phosphatase activity was inhibited in hepatopancreas and nervous ganglion and induced in gills and muscle. Alkaline phosphatase activity was enhanced in gills and hepatopancreas and inhibited in muscle and nervous ganglion. All these enzymes showed recovery after released of crabs into fresh water.

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Influence of desiccation and associated metabolic changes during seed germination in Corypha umbraculifera Linn

Influence of desiccation and associated metabolic changes during seed germination in Corypha umbraculifera Linn

Viji V., Ratheesh Chandra P., Salim Nabeesa, Puthur Jos T.

Статья научная

Corypha umbraculifera L. is a monocarpic palm, which usually flowers after 30-60 years of growth. In C. umbraculifera seeds are the only propagating unit, but the germination rate is very low and seeds are highly recalcitrant. In this context, it was imperative to investigate the desiccation sensitivity, physiological and biochemical changes accompanying the desiccation and germination in C. umbraculifera seeds. Therefore, to make a detailed study, freshly collected C. umbraculifera seeds were desiccated at room temperature for a period of 35 d and physiological and biochemical changes during desiccation and germination were monitored at an interval of 7 d. It was observed that there was a sharp decline in the moisture content of the seed as desiccation proceeded. As the desiccation period progressed, the germination percentage decreased which was below 50% after 35 d. The dry weight percentage of the embryo and endosperm increased with the desiccation period and the increase in dry weight of embryo was significant in comparison with the endosperm. Total protein content of embryo was more compared to that of the endosperm. Peroxidase activity in the embryo was increased up to 28 d of desiccation and decreased further. The endosperm registered a gradual reduction of peroxidase activity during desiccation. In contrast, SOD activity in the embryo was comparatively higher in the fresh seeds and further declined during desiccation, while that of the endosperm remained almost unaltered. The results give a strong indication that desiccation in C. umbraculifera is accompanied by abundant activity of peroxidase in embryo, thereby viability is retained up to 35 days. Whereas, feeble activity of SOD is not seen to be linked with seed viability of C. umbraculifera.

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Influence of growth regulators on secondary metabolites of medicinally important oil yielding plant Simarouba glauca dc. under water stress conditions

Influence of growth regulators on secondary metabolites of medicinally important oil yielding plant Simarouba glauca dc. under water stress conditions

Awate P.D., Gaikwad D.K.

Статья научная

One year old seedlings of Simarouba glauca were subjected to water stress for 4, 8, 12 and 16 days. The foliar sprays of 50 ppm salicylic acid (SA) and 10 ppm Putriscine, Gamma amino butyric acid (GABA) and Abscisic acid (ABA) were applied before and after water stress. It was observed that polyphenols, tannins, alkaloid and flavonoid contents were increased with increasing water stress treatments. Foliar applications of growth regulators ameliorate water stress and exhibits induction of secondary metabolites like coumarins, sterols, xanthoproteins, cardiac glycosides and saponins. It was also noticed that foliar application of SA, GABA, ABA considerably increases all these secondary metabolites which will help to improve the medicinal potential of Simarouba glauca under water stressed condition.

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Influence of nitrogen compounds on growth and the nitric oxide (NO) content in roots of etiolated pea seedlings

Influence of nitrogen compounds on growth and the nitric oxide (NO) content in roots of etiolated pea seedlings

Glyanko A.K., Mitanova N.B., Ischenko A.A.

Статья научная

The data on the influence of different concentration of sodium nitroprusside (SNP), potassium nitrate (KNO3), sodium nitrite (NaNO2) and L-arginine on 3 days-old etiolated pea seedlings growth and nitric oxide (NO) content in roots of these seedlings are obtained. It is found that 24 h exposition of seedlings to SNP showed negative influence on growth at a 4 mM dose; SNP at 0.05 mM doze stimulates their growth and 0.1 mM doze did not influence on seedlings growth. Using KNO3 negative influence on growth at the same exposition was showed only at superhigh concentration - 20 mM. Using NaNO2 negative influence on growth was shown at a doze of 2 mM but concentration of 0.1 and 0.5 mM did not influence on it. The exposition of seedlings to L-arginine caused growth inhibition already at concentration of 0.5 mM and reached maximum at 4 mM doze. Determination of NO level in roots using fluorescent probe DAF-2DA in variants with the greatest growth inhibition has showed, that the maximal inhibition of growth in roots and highest level of NO in roots in variants with SNP (4 mM) and NaNO2 (2 mM) was observed. In variants with KNO3 (20 mM) and L-arginine (4 mM) maximal growth inhibition did not coincide with NO accumulation and was observed after 30 min after the beginning of plants exposition and further it was reduced in 24 h. Results are discussed in connection with possible influence NO and participation of the investigated connections in generation nitric oxide in roots of pea seedlings.

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Influence of salicylic and succinic acids on antioxidant enzymes activity, heat resistance and productivity of Panicum miliaceum L

Influence of salicylic and succinic acids on antioxidant enzymes activity, heat resistance and productivity of Panicum miliaceum L

Kolupaev Yu.ye., Yastreb T.O., Karpets Yu.V., Miroshnichenko N.N.

Статья научная

The influence of treatment of millet (Panicum miliaceum L.) seeds with the solutions of salicylic and succinic acids on the heat resistance of plantlets and activity of antioxidant enzymes - superoxide dismutase (SOD), catalase and peroxidase - in them have been investigated. In the micro-field experiment the influence of these acids on the millet yield was estimated. The action of salicylic (10 μM) and succinic (1 mM) acids caused the increase of plantlets resistance to the damaging heating that expressed in the rise of relative quantity of survived plantlets in 5 days after heating at the temperature of 47°С and in the reduced content of lipid peroxidation product malonic dialdehyde during the poststress period. The increase of activity of SOD, catalase and peroxidase took place in millet plantlets under the influence of salicylic and succinic acids. The increase of productivity of millet grain under the action of salicylic and succinic acids on 13,3-52,0 and 6,4-38,8% respectively depending on weather conditions in the field experiments was noted.

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Influence of salinity stress on proteomic profiles of Cicer arietinum L

Influence of salinity stress on proteomic profiles of Cicer arietinum L

Johnson M., Renola Joy jeba ethal T., Babu A.

Статья научная

The present study was aimed to study the influence of salt stress on the proteomic profiles of Cicer arietinum L. by using SDS-PAGE. Seedlings of Cicer arietinum were exposed to different salt concentrations (4%, 6%, 8% and 10%) of NaCl. Multiple regions of actively stained system were obtained for SDS-PAGE. On 15th day, a total of 79 bands were observed and their RM values ranged from 0.011 to 0.988. Based on the occurrence and non-occurrence of the proteins in the gel system, the protein profiles were classified in to three categories viz., salt tolerant proteins, salt inducible proteins and salt sensitive proteins.

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Influence of slavinorm on resuscitation of rats cardiorespiratory functions under deep hypothermia

Influence of slavinorm on resuscitation of rats cardiorespiratory functions under deep hypothermia

Arokina N.K.

Статья научная

The problem of resuscitating a man whose respiration and heart were arrested under strong cooling is urgent for the reanimation practice. The aim of this work was to study the influence of Slavinorm (a polypeptide complex of the vessels) on the heart work activation and the regeneration of their inherent respiration in the Wistar rats with the help of artificial ventilation of lungs (ALV) and warming the sternum region under deep hypothermia. The animals narcotized with urethan were cooled in water (9,2±0,5ºС) up to the arrest of respiration. The experimental group of rats 1 h before cooling were injected intraperitoneally with Slavinorm (15,6 mg/kg of weight) and the control rats were injected with physiological solution. In control rats the arrest of respiration was observed at the rectal temperature (Тr) 16,0±0,3ºС, in the esophagus (Te) 19,1±0,3ºС. The artificial lung ventilation (ALV) and heating the breast region resulted in the initiation of natural respiration in 29,2±0,4 min from the beginning of ALV at Tr 13,8±0,2ºС, Тe 16,1±0,2ºС. The conclusion: Slavinorm increases the resistance of an organism to cold, assists the prolongation of the process of cooling up to the arrest of respiration, decreases the temperature thresholds of the heart activation and resuscitation of natural respiration.

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Influence of sucrose and cytokinin stress on shoot regeneration in cotyledon culture of oilseed crop black sesame (Sesamum indicum L.)

Influence of sucrose and cytokinin stress on shoot regeneration in cotyledon culture of oilseed crop black sesame (Sesamum indicum L.)

Abirami K., Vikrant

Статья научная

This study involves the evaluation of in vitro shoot regeneration during cotyledon culture in black sesame ( Sesamum indicum L. cv. TMV3) under various concentrations of sucrose and cytokinin (BAP) in Murashige and Skoog (MS) nutrient medium. Cotyledon explants were cultured on MS basal medium supplemented with various concentrations of sucrose (2%, 4%, 6%, and 8%) and combinations of BAP (1.0mg/L, 2.5mg/L, 3.5mg/L, 4.5mg/L, 5.5mg/L, 6.5mg/L, and 7.5mg/L) and IAA (1.0mg/L). The multiple-shoot regeneration was achieved after 5-weeks of culture initiation. Significantly, the maximum mean percentage of shoot regeneration (75±4.3%) and number of shoots/explants (1.3±0.8) was recorded with explants that were treated with MS medium supplemented with sucrose (4%) including BAP (3.5mg/L) and IAA (1.0mg/L) while the high concentration (8%) of sucrose was proved to be completely ineffective to induce shoot regeneration on same nutrient medium (BAP+IAA). Furthermore, results indicate that sucrose (8%) could be observed slightly effective for shoot regeneration with higher concentrations of BAP (6.5mg/L and 7.5mg/L) in presence of IAA (1.0mg/L). Significantly, cotyledon explants that were growing with low concentration of sucrose (2%) were failed to show regeneration if BAP concentration exceeds to (5.5mg/L). Moreover, optimal frequency of shoot regeneration (64.4±1.4%) could be recorded with 2% of sucrose in presence of lower concentration of BAP (2.5mg/L) and IAA (1.0mg/L). The regenerated shoots were further transferred to half strength of MS medium supplemented with various concentrations of IBA (0.5, 1.0, and 1.5mg/L) for induction of roots and complete plantlets formation. Significantly, optimal mean percentage of shoots showing root formation (90±2.8%) was obtained in shoots regenerated with 4% of sucrose in presence of IBA (1.0mg/L) and shoot-root length ratio was recorded to be the maximum (4.2±0.11cm/2.81±0.12cm). However, in contrast, shoots that were regenerated on medium containing high sucrose (8%) with high BAP (7.5mg/L) + IAA (1.0mg/L) were found to exhibit lack of root formation irrespective of IBA concentrations. Present study reports that sucrose and BAP contents of the medium influences the sesame cotyledon explants regeneration. In comparison to control (2%) of sucrose, increase in sucrose concentration (4%) with BAP (3.5mg/L) and IAA (1.0mg/L) proved to be the optimal combination for shoot regeneration and moreover, regenerated shoots could induce the maximum root length in MS1/2 medium supplemented with IBA (1.0mg/L). In contrast, the IBA medium containing very high concentration of sucrose (8%) was turned out to be completely inhibitory for root regeneration. Study indicates that concentration of sucrose and BAP cytokinin in nutrient medium influences considerably the regeneration potential of explants tissues in black sesame oil crop. Moreover, the regenerated plantlets were further gradually acclimatized and transferred to plastic cup soil under the greenhouse conditions.

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Influence of tert-butyl hydroperoxide and nitrosoglutathione on Escherichia coli cells expressing leghemoglobin

Influence of tert-butyl hydroperoxide and nitrosoglutathione on Escherichia coli cells expressing leghemoglobin

Kosmachevskaya O.V., Shumaev K.B., Arredondo-peter R., Topunov A.f

Статья обзорная

Influence of expressed leghemoglobin on stability of Escherichia coli cells to reactive oxygen and nitrogen species - fert-butyl hydroperoxide and S-nitrosoglutathione was studied. We determined both action of these compounds on cells with different level of leghemoglobin expression and peroxidase activity of the cells. It was shown that priority of pro- or antioxidant properties of leghemoglobin is dependent on its concentration in the cells. In cells with reduced synthesis leghemoglobin mostly functions as prooxidant, in cells with intensive one - as antioxidant

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Influence of waterlogging on carbohydrate metabolism in ragi and rice roots

Influence of waterlogging on carbohydrate metabolism in ragi and rice roots

Kulkarni S.S., Chavan P.D.

Статья научная

Effect of different durations of waterlogging (4, 8 and12 days) stress on carbohydrate status and activities of some related enzymes in ragi and rice roots was studied. In both ragi and rice roots there was decrease in starch and total sugar content in response to waterlogging conditions. Activity of α amylase was decrease in ragi roots while opposite trend was noticed in case of rice roots. The activity of pyruvate kinase was markedly increased due to 4, 8 and 12 days waterlogging in ragi roots while such increase was noticed in rice roots due to 12 days stress. Treatment of waterlogging caused enhancement in the activity of alkaline inorganic pyrophosphatase in the roots of both ragi and rice.

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Integrative computer analysis of antisense transcripts and miRNA targets in plant genomes

Integrative computer analysis of antisense transcripts and miRNA targets in plant genomes

Orlov Y.L., Dobrovolskaya O., Yuan C.H., Afonnikov D.A., Zhu Y., Chen M.

Статья

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Interaction of bulk and nano titanium dioxide on antioxidant activity of Lallemantia iberica under drought conditions

Interaction of bulk and nano titanium dioxide on antioxidant activity of Lallemantia iberica under drought conditions

Shoarian Sattari Niloufar, Jamei Rashid, Pasban Eslam Bahman, Salehi Lisar Seyed Yahya

Статья научная

This research was carried out to study the effect of Tio2 and nano Tio2 on some chemical compounds in a medicinal plant Lallemantia iberica under water deficit conditions. The experiment was conducted as a factorial arrangement in randomized complete block design with three replications. The first factor was the application of external materials as spraying with 3 levels of control, titanium dioxide and nano titanium dioxide, and the second factor was 100% (non stress), 75% (moderate stress) and 35% (severe stress) irrigation content. Stress was applied sixty days after planting to harvesting stage. The catalase and superoxide dismutase activities, total phenol, antioxidant activity with DPPH, total flavonoid and HPLC of phenolic compounds were evaluated in the samples. The results showed a moderate stress and the use of nTiO2 caused a significant increase in phenolic content, total flavonoid and antioxidant activity; severe drought stress significantly reducing these compounds...

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Interactive effects of rice residue and water stress on growth and metabolism of wheat seedlings

Interactive effects of rice residue and water stress on growth and metabolism of wheat seedlings

Amist Nimisha, Singh Narsingh Bahadur, Yadav Kavita

Статья научная

In the present study effects of rice residue with and without water stress were studied on Triticum aestivum L. cv. Shatabadi. The mixture of residue and garden soil in 1:1 ratio was considered as 50% (R 1) and only decomposed residue as 100% (R 2). Garden soil was taken as control. Twenty five seeds were sown in each experimental trays filled with soil mixture according to the treatments. Trays were arranged in two groups. After 15 days one set was subjected to water stress (WS) by withholding water supply for 3 days. Morphological and biochemical parameters of 18 days old seedlings were recorded. Seedling height decreased in all treatments. A gradual decrease in relative water content, pigment and protein contents of wheat seedlings were observed. Sugar and proline contents increased in treatments. An increase in malondialdehyde (MDA) content and antioxidative enzyme activities was recorded. Elevation in catalase activity was observed in all treatments except in plants with water deficit. Ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) activities increased when residue mixed with soil but decreased in seedlings under the combined influence of the residue and water stress. Higher amount of MDA and lower activities of APX and GPX reflected the oxidative damage in seedlings under combined treatments. Rice residue inhibited growth of wheat seedlings. Water stress intensified the effects of residue.

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Interactive effects of salinity and low potassium on growth, physiology response of Houttuynia cordata Thunb. W01-100

Interactive effects of salinity and low potassium on growth, physiology response of Houttuynia cordata Thunb. W01-100

Zou Yu Ting, Dai Sha, Li Jing Ye, Liu Zheng Qiong, Wu Wei

Статья научная

Houttuynia cordata Thunb. is a plant enrichment in potassium in plant was reported. Salinity and low potassium availability are important environmental factors restricting plant growth and productivity throughout the world. The interactive effects of salinity and potassium on growth, water content, chlorophyll content, lipid peroxidation content, ion accumulations and K+/Na+ ratio, and organic accumulations as well as oxidative enzymes were investigated in Houttuynia cordata Thunb.. Plants of three-leaf-stage were selected for uniformity, then treated with four levels of Na+ (50, 100, 200 mmol/L) and K+ (0, 0.6, 1.2, 2.4 mmol/L) for 20 days. Plant biomass production, ratio of root and shoot, root numbers, water content and MDA content significantly declined in the combined effect of salinity and K+ deprivation, and increased with salinity. However, salinity in conjunction with K+ deprivation led to an increase on leaf chlorophyll content, which even increased with increasing salinity levels. As expected, K+ content in plant was positive correlated with supplementary K+ concentrations, while Na+ was well correlated with salinity, especially enhanced by the interactive effects of salinity and K+ deprivation. Soluble sugar and proline contents remarkable increased by the highest salinity. SOD activity also substantial increased by the highest salinity, and increased with supplementary K+ concentrations. However, elevated CAT and POD activities were not accompanied with an increase in SOD activity.

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Investigating the ability of diverse native bacillus species to produce hydrolytic enzymes using agar plate assay

Investigating the ability of diverse native bacillus species to produce hydrolytic enzymes using agar plate assay

Harba M., Bakri Y., Jawhar M.

Статья научная

Hydrolytic enzymes of Bacillus attracting a great attention due to their various applications in industrial bioprocesses. In this work, out of 525 Bacillus isolates, 40 were screened for their potential capacity to produce hydrolytic enzymes including xylanase, lipase, amylase, pectinase, protease and carboxymethyl cellulose (CMC) using agar plate assay. A pure culture of each isolate was streaked on the surface of agar media containing suitable substrate specific for every enzyme activity, and the diameter of hydrolytic zones were measured. Data showed clear zones around the colonies which were interpreted as evidence of the enzymes activities. The isolates were able to generate at least one of these enzymes among which CMC and protease were the most common enzymes detected in 40 isolates; amylase in 39, xylanase in 36, lipase in 32 and pectinase in 26. Based on 16S rRNA gene sequencing the isolates were classified as B. atrophaeus , B. amyloliquefaciens , B. subtilis , Paenibacillus polymyxa , B. simplex and B. tequilensis . The native B. tequilensis isolates formed the largest zone clearance and had high abilities to produce five hydrolases. The isolates which had the largest enzymatic activity zones and the largest diameter of the clear hydrolysis zones on agar plates were submitted for further research work and enzyme-based industrials.

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Investigation of brain creatine levels under the mental stress conditions

Investigation of brain creatine levels under the mental stress conditions

Burjanadze George, Dachanidze Natalia, Kuchukashvili Zurab, Chachua Matrona, Menabde Ketevan, Koshoridze Nana

Статья научная

Alterations in brain creatine levels are considered to be associated with various pathological conditions. However, there is still no exact evidence on character of this changes and clear link between disorders and upstream and downstream direction of creatine changes. Chronic mental stress conditions are thought to be connected with upstream regulation of cellular oxidative pathways, thus oxidizing various structural and active compounds. Oxidative stress also takes part in increase of permeability of blood brain barrier (BBB) that, in turn, makes it possible for a number of molecules to cross the BBB in both directions. Observations on long-term social isolation and circadian rhythm violation show a rising trend in brain creatine amount, while there was remarkable down-regulation in creatine synthesizing system, as the key-enzymes’ (AGAT and GAMT) activity was decreased. Investigations of BBB permeability for creatine under the stress conditions by mass-spectrometric analyses revealed no changes in creatine transport in the stress group, compared to the control. However, the activity of mitochondrial CK was reduced for about 25% and Vmax had fallen down in the stressed group, the Km was not drastically changed. To sum up, it could be supposed that the reason for the elevations of creatine levels in brain under the mental stress conditions could be stimulated by the activated oxidative stress that induces conformational changes in mitochondrial Creatine Kinase structure and decreasing the ability of enzyme to phosphorylate the creatine and as a result free creatine levels in brain are being arisen.

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