Wyniki wyszukiwania - Biblioteka Nauki

1

Light and scanning electron microscopy of an ischnoceran louse, Felicola rohani, and an amblyceran louse, Heterodoxus spiniger (Phthiraptera: Insecta) from the Indian grey mongoose, Herpestes edwardsii

100%

Ahmad A. , Gupta N.

Annals of Parasitology

|

2021

|

tom 67

|

nr 2

2

A validated stability-indicating method for simultaneous analysis of mevastatin and pravastatin in fermentation broth during bioconversion by Actinomadura macra

80%

Ahmad A. , Panda B. P. , Mujeeb M.

Acta Chromatographica

|

2011

|

tom Vol. 23, no. 1

121--131

EN

A simple, accurate, selective, precise, economical, and stability-indicating high-performance thin-layer chromatographic method for simultaneous analysis of mevastatin and pravastatin in fermentation broth has been established and validated. Compounds were separated on aluminium foil TLC plates precoated with silica gel 60F254; the mobile phase was toluene-ethyl acetate-formic acid 3:2:1 (v/v), which gave compact bands of mevastatin and pravastatin (RF 0.48 ± 0.02 and 0.31 ± 0.02, respectively). Detection at 237 nm resulted in r = 0.992 and 0.995 for mevastatin and r = 0.995 and 0.994 for pravastatin, for peak height and peak area, respectively. The limits of detection and quantification for mevastatin were 20.1 and 60.8 ng per band, and for pravastatin 19.2 and 58.3 ng per band, respectively. The method enabled effective quantification of mevastatin and pravastatin in the fermentation broth of Actinomadura macra and can therefore be used as a stability-indicating method for routine analysis of these compounds during bioconversion.

3

Penicillium oxalicum directed systemic resistance in tomato against Alternaria alternata

80%

Ahmad A. , Shafique S. , Shafique S. , Akram W.

Acta Physiologiae Plantarum

|

2014

|

tom 36

|

nr 05

EN

Enhanced yield of tomato has ever been an important issue due to its nutritional value and various dietary consumption forms. But, efficient yield increase can never be achieved without using environmentally safe means e.g. innate resistance. In present study, tomato innate antifungal resistance has been boosted up using Penicillium oxalicum, and then various aspects of resistance modulation have been explored in details. Two tomato varieties of differential antifungal resistance (Dinaar and Red Tara) were treated with six P. oxalicum strains which screened the best inducer strain (Pn 5); which remarkably controlled disease incidence (DI) of Alternaria alternata. Inducer was not only responsible for almost two times production of phenolics, alkaloids and terpenoids in Red Tara, but it also non-significantly triggered same biochemicals in Dinaar. Hemicellulose showed only 40 % increase in variety of least antifungal resistance. During quantification assays of peroxidase (POD), phenyl ammonia lyase and polyphenol oxidase, more or less the same doubling trend was recorded in susceptible variety, while only POD had significant enhancement in resistant variety under the influence of fungal inducer. It was also recorded that inducer not only modulated quantity of enzyme (glucanase), but its isozyme package was also altered. Colorimetric quantifications of lignin, cellulose and pectins proved that biotic inducer strengthened the physical structure of plant cells by increasing these contents from 30 to 120 %. The above investigation collectively comes with the recommendation of an efficient and environmentally safe inducer (P. oxalicum); which, can be used to control fungal pathogens.

4

Development and Validation of RP-HPLC Method for Simultaneous Estimation of Glibenclamide and Thymoquinone in Rat Plasma and Its Application to Pharmacokinetics

80%

Ahmad A. , Khan R. M. A. , Alkharfy K. M.

Acta Chromatographica

|

2015

|

tom Vol. 27, no. 3

435--448

EN

A rapid, accurate, and sensitive reverse phase high-performance liquid chromatographic method was developed and validated for the simultaneous determination and quantification of glibenclamide and thymoquinone in rat plasma in the presence of internal standard (thymol). Chromatograms were developed with methanol, acetonitrile, and buffer (50:20:30, v/v/v) solvent system on a Symmetry® C18 (5 μm, 3.9 × 150 mm) column, and pH was adjusted to 4.5 with orthophosphoric acid. Mobile phase was pumped at a flow rate of 1.5 mL min-1 with 254 nm ultraviolet (UV) detection. Validation of the method was performed in order to demonstrate its selectivity, linearity, precision, accuracy, limits of detection, and quantification (LOD and LOQ). Standard curves were linear (r2 = 0.996 and 0.999 for glibenclamide and thymoquinone) over the concentration range 0.5–50 μg Ml-1. The coefficient of variation (CV) of < 6% and accurate recovery of 87.54–105.19% for glibenclamide and CV of <5% and accurate recovery of 86.08–103.19% for thymoquinone were found to be in the selected concentration range of 0.5–50 μg Ml-1. The lower limits of detection and quantitation of the method were 0.109 and 0.332 μg Ml-1 for glibenclamide and 0.119 and 0.361 μg Ml-1 for thymoquinone, respectively. The within and between-day coefficients of variation were less than 7%. The validated method has been successfully applied to measure the plasma concentrations in a drug interaction study of glibenclamide with thymoquinone in an animal model to illustrate the scope and application of the method.

5

Cd, As, Cu, and Zn transfer through dry to rehydrated biomass of Spirulina platensis from wastewater

80%

Ahmad A. , Ghufran R. , Wahid Z. A.

Polish Journal of Environmental Studies

|

2010

|

tom 19

|

nr 5

EN

Phytoremediation of Cd, As, Cu, and Zn by Spirulina Platensis is one of the most cost-effective approaches and environmental friendly technologies used to remediate contaminants from contaminated water. The removal rates of Cd, As, Cu, and Zn in the field experiment were 14.95, 9.45, 35.55, and 73.95 μg/g/d, respectively. The highest concentrations of these metals accumulated in S. Platensis after 90 d of the laboratory/field collected samples were 58.9/98.68, 29.86/47.98, 43.28/235.86, and 249.67/390.65 μg/g dry wt., respectively, over the experiment. Only 55% Cd, 35% As, 85% Cu, and 95% of Zn removed from the water were used by S. Platensis. The bioconcentration factors were recorded for the metals in field/laboratory: for Cd (BCF=90/536), As (BCF=135/2,155), Cu (BCF=34,200/62,300) and Zn (BCF=32,500/95,300). The data obtained suggest that cyanobacterium S. Platensis has promising potential and can be used in a synergistic way to remediate wastewater polluted by Cd, As, Cu, and Zn.

6

Phenolic, carotenoid, ascorbic acid contents and their antioxidant activities in bell pepper

80%

Akhtar M. , Ahmad A. , Masud T. , Wattoo F. H.

Acta Scientiarum Polonorum. Hortorum Cultus

|

2019

|

tom 18

|

nr 1

EN

Essential nutritional components are quantified in the study in addition to major antioxidants, carotenoids, phenols and flavonoids. Their antioxidant activities were also analyzed using DPPH, ABTS and hydrogen peroxide radical scavenging activities and by determining their iron reducing power. Results indicated that the highest quantity of nutritional and antioxidant components was obtained in red variety (4.63 mg/g ascorbic acid, 10.32 mg/g total carotenoid content, 61.50 mg/g total flavonoid content, 310.27 mg/g total phenolic content) followed by orange, yellow and green varieties. Similar trend was observed while analyzing their antioxidant activities by different methods. In studying correlation between components and antioxidant activity, a strong correlation was obtained for ABTS radical scavenging activity with total phenolic content (R2 = 0.722) and total carotenoid contents (R2 = 0.709), while moderate correlation was observed for ABTS radical scavenging activity with total flavonoid contents (R2 = 0.517) and ascorbic acid (R2 = 0.673).

7

Comparative roles of brassinosteroids and polyamines in salt stress tolerance

80%

Fariduddin Q. , Mir B. A. , Yusuf M. , Ahmad A.

Acta Physiologiae Plantarum

|

2013

|

tom 35

|

nr 07

EN

Salt stress is among the major abiotic stresses that adversely affect the global crop production and its adverse impacts are getting more serious in the regions where saline water is used for irrigation. It induces reactive oxygen species, alters the activity of antioxidant system and adversely affects the process of photosynthesis. Various strategies have been employed to mitigate the deleterious effects of salt stress. Presently, the recommended strategies to overcome the adverse effects of salt stress include the use of tolerant cultivars, ameliorative water management and diverse cultural practices. However, none of these approaches have been found to be fully effective under salt stress conditions. An alternative and technically simpler approach to induce salt stress tolerance is the exogenous application of plant growth regulators (PGRs). This technique has gained significant importance during the past decade. PGRs have been implicated to regulate a wide range of metabolic and physiological activities in plants, ranging from cell division and organogenesis to protection against biotic and abiotic stresses. One of the important factors for enhanced plant productivity by PGRs is their efficiency to overcome the salt-induced stress conditions. Recent findings on the effects of brassinosteroids and polyamines on the salt stress tolerance of crops open new avenues to address the salinity problems. This review enlightens the role of brassinosteroids and polyamines in different plant processes like their role in regulation of photosynthesis, antioxidant systems and other related aspects, thereby improving overall performance of plants.

8

Phosphate-induced changes in fatty acid biosynthesis in Chlorella sp. KS-MA2 strain

80%

Ahmad A. , Osman S. M. , Cha T. S. , Loh S. H.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

|

2016

|

tom 97

|

nr 4

9

Changes in growth, lipid peroxidation and some key antioxidant enzymes in chickpea genotypes under salt stress

80%

Rasool S. , Ahmad A. , Siddigi T. O. , Ahmad P.

Acta Physiologiae Plantarum

|

2013

|

tom 35

|

nr 04

EN

The present study was conducted to evaluate the effect of NaCl on growth and some key antioxidants in chickpea. Eight genotypes of chickpea were grown hydroponically for 15 days and then treated with different concentrations of salt [0 mM (T0), 25 mM (T1), 50 mM (T2), 75 mM (T3), and 100 mM (T4)]. Salinity showed marked changes in growth parameters (fresh and dry weight of root and shoot). The level of lipid peroxidation was measured by estimating malondialdehyde content. Lipid peroxidation increases with the increase in NaCl concentration in all genotypes but salt-tolerant genotypes (SKUA-06 and SKUA-07) were least affected as compared to other genotypes. The chlorophyll content was also affected with elevated levels of NaCl. Increased concentration of salt increased the activity of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase in all chickpea genotypes but maximum activity was observed in salt-tolerant (SKUA-06 and SKUA-07) genotypes. Two genotypes of salt-tolerant and salt-sensitive varieties were analyzed further by real time PCR which revealed that the expression of SOD, APX and CAT genes were increased by NaCl in the salt-tolerant variety. The enhancement in tolerance against salt stress indicates that the genes involved in the antioxidative process are triggered by oxidative stress induced by environmental change. The results indicate that NaCl-induced oxidative stress hampers the normal functioning of the cell. The efficient antioxidants play a great role in mitigating the effect of NaCl stress in chickpea. This screening of NaCl-tolerant genotypes of chickpea can be performed on salt-affected land.

10

A comparative effect of IAA and 4-Cl-IAA on growth, nodulation and nitrogen fixation in Vigna radiata (L.) Wilczek

80%

Ali B. , Hayat S. , Aiman Hasan S. , Ahmad A.

Acta Physiologiae Plantarum

|

2008

|

tom 30

|

nr 1

EN

The plants of mung bean (Vigna radiata L. Wilczek) were raised from the seeds soaked in water (control), IAA or 4-C-IAA (10⁻⁶, 10⁻⁸ or 10⁻¹⁰ M) for 8 or 12 h. The plants were allowed to grow in a net house and were sampled at 30 and 45 days after sowing (DAS). Both IAA and 4-Cl-IAA significantly affected the growth (length, fresh and dry mass of roots and shoots), the number of nodules, their fresh and dry mass and the activity of nitrogenase. However, the contents of nitrogen and carbohydrate exhibited a decrease in response to both the auxins. 4-Cl-IAA, at a concentration of 10⁻⁸ M, generated the best response. Moreover, 4-Cl-IAA at other two concentrations (10⁻⁶ and 10⁻¹⁰ M) was much more active than any of the IAA concentration used.

11

In vitro propagation and the acclimatization effect on the synthesis of 2-hydroxy-4-methoxy benzaldehyde in Decalepis hamiltonii Wight and Arn.

80%

Sharma S. , Shahzad A. , Ahmad A. , Anjum L.

Acta Physiologiae Plantarum

|

2014

|

tom 36

|

nr 09

EN

The present study reports a high frequency in vitro propagation protocol through apical bud sprouting and basal organogenic nodule formation in shoot tip explants of Decalepis hamiltonii, an endemic and endangered medicinal liana. Among different combinations of plant growth regulators (PGRs) and growth additives, maximum of 8.20 shoots per explant with mean shoot length of 6.54 cm were induced on Murashige and Skoog’s medium (MS) supplemented with 5.0 µM 6-benzyladenine (BA) + 0.5 µM indole-3-acetic acid (IAA) + 30.0 µM adenine sulphate (ADS) through apical bud sprouting. On single cytokinin treatment explants did not exhibit good multiplication but showed nodulation (N₁) from the basal cut end similar to cytokinin–auxin combination (N₂). Between two types of nodular tissues, N₂ was proved to be better for maximum shoot regeneration (15.40 shoots per explant) and shoot length (4.56 cm) when cultured on MS medium supplemented with 5.0 µM BA, 0.5 µM IAA, 30.0 µM ADS and 1.0 µM gibberellic acid (GA₃). Microshoots were efficiently rooted on half-strength MS medium supplemented with 2.5 µM α-naphthalene acetic acid (NAA). After successful acclimatization in Soilrite, 95.10 % plantlets were survived in field conditions. Histological investigation proved useful in ascertaining the callogenic nature of the regenerating nodular tissue formed at the basal cut end of shoot tip explant. Acclimatized plantlets were studied for the estimation of chlorophyll and carotenoid content as well as the net photosynthetic rate (PN) during subsequent days of transfer to ex vitro condition. Moreover, acclimatization had a significant effect on biomass production and the synthesis of 2-hydroxy-4-methoxy benzaldehyde (2HMB). Maximum fresh weight (3.78 gm/plant), dry weight (0.39 gm/plant) of roots and 2HMB content (15.94 µg/ml of extract) were noticed after 8 weeks of acclimatization.

12

Growth of wheat seedlings raised from the grains treated with 28-homobrassinolide

80%

Hayat S. , Ahmad A. , Hussain A. , Mobin M.

Acta Physiologiae Plantarum

|

2001

|

tom 23

|

nr 1

13

Exogenous spermidine- and kinetin-mediated changes in the content of heavy metal elements and the biomass of mash bean grown in chromium and lead polluted soils

71%

Yasin G. , Saima S. , Haq I. , Altaf A. , Ahmad A.

Journal of Elementology

|

2022

|

tom 27

|

nr 3

14

Orally administered endoxifen inhibits tumor growth in melanoma-bearing mice

71%

Chen P. , Sheikh S. , Ahmad A. , Ahmad U. , Ahmad I.

Cellular and Molecular Biology Letters

|

2018

|

tom 23

EN

Endoxifen, an active metabolite of tamoxifen, has been shown to be an effective anti-estrogenic agent in estrogen receptor-positive breast cancer patients. In melanoma, estrogen receptor expression is shown to be associated with disease progression. However, the therapeutic benefit of endoxifen in melanoma has not yet been evaluated. Here, we present the first demonstration of the anti-melanogenic activity of endoxifen in vitro and in vivo. The in vitro cytotoxic effect of endoxifen was tested using a cell viability assay. The in vivo anti-melanogenic activity was evaluated in B16F10 cell-bearing C57BL/6 mice, a mouse melanoma model. The general toxicity was tested in Swiss albino mice. Endoxifen exhibited greater activity against melanoma cell lines. Treatment of B16F10 mouse and SK-MEL-5 human melanoma cell lines with 10 μM of endoxifen for 48 h respectively resulted in 93.6 and 92.5% cell death. Orally administered endoxifen, at dose levels of 4 and 8 mg/kg body weight/day for 20 consecutive days, respectively reduced metastatic melanoma nodules in the lungs by 26.7 and 82.7%. Endoxifen was found to be a safe and effective anti-melanogenic agent in animal studies.

15

Inhibition of hypoxia-induced tolerance to subsequent hyperoxic injury in lung cells by phosphatidyl inositol 3-kinase inhibitors: LY294002 and wortmannin

70%

Ahmad S. , Ahmad A. , Gerasmivoskaya E. , Stenmark K. R. , White C. W.

Cellular and Molecular Biology Letters

|

2003

|

tom 08

|

nr 2A

16

Development and validation of HPTLC method for the estimation of diosgenin in In Vitroculture and rhizome of Dioscorea deltoidea

61%

Amir M. , Ahmad A. , Siddique N. A. , Mujeeb M. , Ahmad S. , Siddique W. A.

Acta Chromatographica

|

2012

|

tom Vol. 24, no. 1

111--121

EN

A new simple, accurate, selective, precise, economical and stability-indicating high-performance thin layer chromatographic method for the analysis of diosgenin in callus and rhizome of Dioscorea deltoidea was developed and validated. The method was developed on TLC aluminium plates precoated with silica gel 60F254 using solvent system petroleum ether-isopropanol (12:1, v/v), which gives a compact spot of diosgenin (RF value 0.76 ± 0.02). Densitometric analysis of diosgenin was carried out in the absorbance mode at 366 nm after spraying with methanolic sulphuric acid. The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.991 and 0.995 for diosgenin with respect to peak height and peak area, respectively, in the concentration range of 100–1000 ng per spot. The limits of detection and quantification for diosgenin were 16.58 and 50.25 ng per spot. The proposed method was applied for determination of diosgenin in rhizome of D. deltoidea (0.047% w/w) as well as in in vitro culture (callus) (0.092% w/w). Statistical analysis proves that the method is repeatable, selective and accurate for the estimation of diosgenin in D. deltoidea. The developed method effectively resolved the diosgenin in D. deltoidea; hence, it can be employed for routine analysis as a stability indicating method.

17

Role of Acinetobacter sp. CS9 in improving growth and phytoremediation potential of Catharanthus longifolius under cadmium stress

61%

Yasin N. A. , Khan W. U. , Ahmad S. R. , Ahmad A. , Akram W. , Ijaz M.

Polish Journal of Environmental Studies

|

2019

|

tom 28

|

nr 1

EN

Some rhizobacteria are capable of improving metal tolerance and growth of plants under heavy metal stress. The objective of the current study was isolation and subsequent application of cadmium-resistant rhizobacteria in phytoremediation by Catharanthus longifolius. The screened bacterial isolate exhibited growth-promoting attributes, including phosphate solubilization, ACCD activity, auxin, and siderophores production. The inoculation of Acinetobacter sp. CS9 under greenhouse trial improved growth and phytoextraction capability of C. longifolius plants in soils contaminated with different concentrations (0, 100, and 200 mg kg⁻¹) of Cd. The plants exhibited reduced quantity of total soluble protein, soluble sugars, and chlorophyll contents under Cd stress. On the other hand, improved chlorophyll, soluble protein, and sugar contents were observed in Acinetobacter sp. CS9-treated plants. The inoculated plants exhibited improved activity of antioxidant enzymes (SOD and CAT) and reduced malondialdehyde levels. Moreover, higher Cd uptake and translocation ratio was observed in Acinetobacter sp. CS9-inoculated plants as compared to un-inoculated ones. The current study showed that Acinetobacter sp. CS9 reduced Cd-induced oxidative stress and improved the phytoremediation capability of C. longifolius.

18

Foliar application of nutrient for augmentation of rhizospheric heavy metal stress - growth and productivity of canola (Brassica napus L.) measured with indices

61%

Ahmad A. , Saima S. , Parveen M. , Ali E. , Arif M. , Yasin G. , Akmal F.

Journal of Elementology

|

2023

|

tom 28

|

nr 1

19

AM1 is a potential ABA substitute for drought tolerance as revealed by physiological and ultra-structural responses of oilseed rape

61%

Naeem M. S. , Dai L. , Ahmad F. , Ahmad A. , Li J. , Zhang C.

Acta Physiologiae Plantarum

|

2016

|

tom 38

|

nr 07

20

The utilization of microbes for sustainable food production

61%

Noor-Hassim M. F. B. , NG C. L. , Teo H. M. , Azmi W. A. , Muhamad-Zalan N. B. , Karim N. A. B. , Ahmad A.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

|

2023

|

tom 104

|

nr 2