Studying the effects of heavy metal on chlorophyll and sugar in one year-old seedlings organs of Acer velutinum specie

Pollution is one of the most important factors inhibiting growth in the environment; therefore the effects of zinc pollution were studied in Acer velutinum specie. Two years old seedlings of Acer velutinum specie were prepared from nursery, the concentrations of zero and one hundred and thirty mg per liter of zinc chloride solution were added to the soil of seedlings pots after calculating and after passing a three-month period of seedling growth, the plant organs were removed, then the amount of zinc concentration in the samples was determined and data were analyzed. The results of the analysis showed that the highest amount of accumulation on the stem, root and soil in treatment concentrations is 87.75, 65.68 and 24.78 mg per kg and accumulation of zinc in total chlorophyll and sugar in treatment concentrations is 4.61 and 0.6028 mg per g, respectively, and accordingly Acer velutinum specie is suitable for refinement of soils contaminated with zinc.     

Soil microorganisms nitrogen transformation test for abamectin 3.6 g/L EC (w/v) in loamy sand soil

The present study was conducted to determine the nitrogen transformation test of abamectin 3.6 g/L EC. This study was conducted as per OECD Guidelines for the Testing of Chemicals OECD 216. The test item abamectin 3.6 g/L emulsifiable concentrate (EC) was applied in a loamy sand soil and incubated over a period of 28 days for nitrogen transformation test at concentrations of 3.2 μL/kg soil dry weight and 16 μL/kg soil dry weight. The concentrations tested were based on one and five times the maximum recommended field application rates of 1200 mL/ha and 6000 mL/ha of abamectin 3.6 g/L EC, respectively. The deviation in soil nitrate content determined at 28 days after application of the test item to soil compared to the control was 0.14% and ? 9.25% for the single and five times test concentrations, respectively. There is no significant variation between the treatment groups and control sample. The rate of nitrate formation between 14 and 28 days after application of the test item to soil deviate from control by 10.41% and 13.74% for 3.2 and 16 μL/kg soil dry weight, respectively. Deviations in nitrate levels and nitrate formation rates in soil treated with up to and including 16 μL/kg of test item/kg soil dry weight were < 25%, compared to control indicating no significant effect occurred in nitrogen transformation.     

Comparative assessment of in situ bioremediation potential of cadmium resistant acidophilic Pseudomonas putida 62BN and alkalophilic Pseudomonas monteilli 97AN strains on soybean

A study was undertaken to examine the effects of the acidophilic strain 62BN (pH 5.5) and alkalophilic strain 97AN (pH 9.0) on remediation of cadmium and their subsequent effects on soybean (Glycine max var. PS-1347) in acidic and alkaline soils, respectively. The effect of cadmium on soybean plants was studied in acidic (pH 6.3 ± 0.2) and alkaline (8.5 ± 0.2) soil amended with 124 μM CdCl₂ concentration, respectively, and the cadmium toxicity was evident from stunted growth, poor rooting, and cadmium accumulation in each case. Furthermore, 16S ribosomal DNA (rDNA) sequencing identified 62BN as a Pseudomonas putida strain and 97AN as a Pseudomonas monteilli strain. In situ studies showed that on seed bacterization, both the P. putida 62BN strain and P. monteilli 97AN strain were able to enhance plant growth in terms of agronomical parameters, in the presence of cadmium in acidic and alkaline soils, respectively. Apart from this, strain 62BN and 97AN reduced cadmium concentration in plant and soil significantly (p < 0.05) in their respective soil types. Further comparative analysis revealed that P. putida 62BN was more effective than P. monteilli 97AN strain in remediation of cadmium. The bacterial strains offer promise as inoculants to improve the growth of plants in the presence of toxic Cd concentrations in the environment with their optimum pH.     

The impact of iron plaque on La and Nd uptake and translocation in rice (Oryza sativa L.)

The effect of root surface iron plaque formation on the uptake, transfer and accumulation of La and Nd in the rice root system was evaluated by using solution cultures. The results showed that La and Nd pollution stress inhibit formation of rice root surface iron plaques. The amount of La and Nd absorbed by the rice root surface iron plaque rose with the increase of La and Nd solution concentrations. Iron plaque formation on the rice root surface significantly decreases the La and Nd concentrations in rice roots and shoots. At growth solution La concentrations of 0.1, 0.5, and 1.0 mmol.L^? 1, concentrations of La in rice roots with induced iron plaques decreased by 17.1%, 37.4%, and 31.2%, respectively, and concentrations of La in rice shoots decreased by 43.9%, 60.6%, and 27.0%, respectively, when compared to plants with non-induced iron plaques. Also, with Nd solution concentrations of 0.1, 0.5, and 1.0 mmol.L^? 1, the Nd concentrations in rice roots and shoots of plants with induced iron plaques decreased by 21.0–31.7% and 22.7–47.5%, respectively when compared to plants with non-induced iron plaques. Iron plaque formation on the rice root surface affects the accumulation and transfer of La and Nd in rice roots. Accumulation of La and Nd was greater in rice roots than in rice shoots regardless of whether the plants had induced or non-induced iron plaques. Transfer coefficients of iron plague on rice root surface and root system under La treatments were both higher than those under Nd treatment. For rice roots and iron plaques on the root surface, the enrichment coefficient in the La treatment group was less than that in the Nd treatment group, while for rice shoots, the enrichment coefficient in the La treatment group was greater than that in the Nd treatment group. Clearly, the mechanisms governing the effect of iron plaque on La and Nd uptake and transfer in the rice root system are rather complicated.     

Spectral lights trigger biomass accumulation and production of antioxidant secondary metabolites in adventitious root cultures of Stevia rebaudiana (Bert.)

Stevia rebaudiana (S. rebaudiana) is the most important therapeutic plant species and has been accepted as such worldwide. It has a tendency to accumulate steviol glycosides, which are 300 times sweeter than marketable sugar. Recently, diabetic patients commonly use this plant as a sugar substitute for sweet taste. In the present study, the effects of different spectral lights were investigated on biomass accumulation and production of secondary metabolites in adventitious root cultures of S. rebaudiana. For callus development, leaf explants were excised from seed-derived plantlets and inoculated on a Murashige and Skoog (MS) medium containing the combination of 2,4-dichlorophenoxy acetic acid (2, 4-D, 2.0 mg/l) and 6-benzyladenine (BA, 2.0 mg/l), while 0.5 mg/l naphthalene acetic acid (NAA) was used for adventitious root culture. Adventitious root cultures were exposed to different spectral lights (blue, green, violet, red and yellow) for a 30-day period. White light was used as control. The growth kinetics was studied for 30 days with 3-day intervals. In this study, the violet light showed the maximum accumulation of fresh biomass (2.495 g/flask) as compared to control (1.63 g/flask), while red light showed growth inhibition (1.025 g/flask) as compared to control. The blue light enhanced the highest accumulation of phenolic content (TPC; 6.56 mg GAE/g DW), total phenolic production (TPP; 101 mg/flask) as compared to control (5.44 mg GAE/g DW; 82.2 mg GAE/g DW), and exhibited a strong correlation with dry biomass. Blue light also improved the accumulation of total flavonoid content (TFC; 4.33 mg RE/g DW) and total flavonoid production (TFP; 65 mg/flask) as compared to control. The violet light showed the highest DPPH inhibition (79.72%), while the lowest antioxidant activity was observed for control roots (73.81%). Hence, we concluded that the application of spectral lights is an auspicious strategy for the enhancement of the required antioxidant secondary metabolites in adventitious root cultures of S. rebaudiana and of other medicinal plants.     

Production of rhoifolin and tiliroside from callus cultures of Chorisia chodatii and Chorisia speciosa

The current work aims to stimulate the production of rhoifolin and tiliroside as two valuable phytochemicals from Chorisia chodatii Hassl. and Chorisia speciosa A. St.-Hil. callus cultures. A comparison between three explants from the in vitro germinated seedlings of both species for callus induction and accumulation of both flavonoids was carried out. Highly efficient calluses were induced from the leaves, stems and roots of C. chodatii seedlings on Gamborg’s B5 (B5) and Murashige and Skoog (MS) media containing 2.0 mg/l β-naphthalene acetic acid (NAA) and 0.5 mg/l 6-benzyladenin (BA) or kinetin (Kn), while those of C. speciosa seedlings efficiently produced calluses on both media supplemented with 0.5 or 1.0 mg/l NAA and 0.5 mg/l BA. Besides, the highest contents of rhoifolin (1.927 mg/g DW) and tiliroside (1.776 mg/g DW) from C. speciosa cultures were obtained from the calluses of seedlings’ roots and stems maintained on B5 medium containing 1.0 mg/l NAA and 0.5 mg/l BA, respectively. On the other hand, the maximum rhoifolin content (0.555 mg/g DW) from C. chodatii cultures was obtained from the calluses of seedlings’ stems grown on B5 medium supplemented with 2.0 mg/l NAA and 0.5 mg/l BA, whereas the highest tiliroside content (0.547 mg/g DW) was provided by the root explants on B5 medium containing 2.0 mg/l NAA and 0.5 mg/l Kn. Both flavonoids were bioaccumulated in greater amounts than the wild and cultivated intact plants, which provides a promising tool for their future commercial production under a controlled environment, independent of climate and soil conditions.     

Effects of simulated warming on soil ammonia-oxidizing bacteria and archaea communities in an alpine forest of western Sichuan,China

Ongoing climate change, characterized by winter warming, snow cover decline and extreme weather events, is changing terrestrial ecosystem processes in high altitude and latitude regions. Winter soil processes could be particularly sensitive to climate change. In fact, winter warming and snow cover decline are interdependent in cold biomes, and have a synergistic effect on soil processes. Soil microorganisms not only play crucial roles in material cycling and energy flow, but also act as sensitive bio-indicators of climate change. However, little information is available on the effect of winter warming on forest soil ammonia-oxidizing bacteria (AOB) and archaea (AOA). The alpine and subalpine forest ecosystems on the eastern Tibet Plateau have important roles in conserving soil, holding water, and maintaining biodiversity. To understand the changes in AOB and AOA communities under climate change scenarios, an altitudinal gradient experiment in combination with soil column transplanting was conducted at the Long-term Research Station of Alpine Forest Ecosystems, which is situated in the Bipeng Valley of Lixian County, Sichuan, China. Thirty intact soil columns under an alpine forest at an altitude of 3582 m were transplanted and incubated at 3298 m and 3023 m forest sites, respectively. Compared with the 3582 m, we expected air temperature increases of 2 °C and 4 °C at the 3298 m and 3023 m, respectively. However, the temperatures in the soil organic layer (OL) and mineral soil layer (ML) increased by 0.27 °C and 0.13 °C, respectively, at 3023 m and ? 0.36 °C and ? 0.35 °C at 3298 m. Based on a previous study and with simultaneous monitoring of soil temperature, the abundances of AOB and AOA communities in both the OL and ML were measured by qPCR in December 2010 (i.e., the onset of the frozen soil period) and March 2011 (i.e., the late frozen soil period). The soil columns incubated at 3023 m had relatively higher AOB abundances and lower AOA/AOB ratios than those at 3298 m, while higher AOA abundances and AOA/AOB ratios were observed at 3298 m. The abundance of the microbial community at the late frozen period was higher than that at the onset of frozen soil, and the changes in microbial community abundance at the late frozen period were more substantial. Furthermore, the nitrate nitrogen (N) concentrations in both the OL and ML were significantly higher than ammonia N concentrations, implying that soil nitrate N is the primary component of the inorganic N pool in the alpine forest ecosystem. Additionally, the responses of AOA and AOB in the soil OL to soil column transplanting were more sensitive than the responses of those in ML. In conclusion, climate warming alters the abundance of the ammonia-oxidizing microbial community in the alpine forest ecosystem, which, in turn, might affect N cycling.     

Effect of salinisation of soil on growth, water status and general nutrient accumulation in seedlings .of Delonix regia (Fabaceae)

Greenhouse experiments were conducted to assess the effect of salinisation of soil on emergence, growth, water content, proline content and mineral accumulation of seedlings of Delonix regia (Hook.) Raf. (Fabaceae). Sodium chloride (NaCl) was added to the soil and salinity was maintained at 0.3, 1.9, 3.9, 6.0 and 7.9 dS m^?1. A negative relationship between seedling emergence and salt concentration was obtained. Salinity caused reduction in water content and water potential of tissues (leaves, stems, tap roots and lateral roots) that resulted in internal water deficit to plants. Consequently, shoot and root elongation, leaf expansion and dry matter accumulation in leaves, stems, tap roots and lateral root tissues of seedlings significantly decreased in response to increasing concentration of salt. Proline content in tissues was very low. There were no effective mechanisms to control net uptake of Na on root plasma membrane and subsequently its transport to shoot tissues. Potassium content significantly decreased in tissues in response to salinisation of soil. This tree species is a moderate salt-tolerant glycophytic plant. Nitrogen and calcium content in tissues significantly decreased as soil salinity increased. Phosphors content in tissues exhibited a declining trend with increase in soil salinity. Changes in tissues and whole-plant accumulation pattern of other elements tested, as well as possible mechanisms for avoidance of Na toxicity in this tree species in response to salinisation, are discussed.     

Effect of stand age on soil microbial community structure in wolfberry (Lycium barbarum L.) fields

Soil physicochemical properties and microbes are essential in terrestrial ecosystems through their role in cycling mineral compounds and decomposing organic matter. This study examined the effect of stand age on soil physicochemical properties and microbial community structure in wolfberry (Lycium barbarum L.) fields, in order to reveal the mechanism of soil degradation due to long-term stand of L. barbarum. The objective of the study was achieved by phospholipid fatty acid (PLFA) biomarker analysis of soil samples from L. barbarum fields in Zhongning County, Ningxia Province—the origin of L. barbarum. Five stand ages of L. barbarum were selected, < 1, 3, 6, 9, and 12 years (three plots each). The results showed that soil bulk density increased slightly with increasing stand age, while no clear trend was observed in soil pH or total salinity. As the stand age increased, soil organic matter and nutrients first increased before decreasing, with the highest levels being found in year 9. There was an amazing variety of PLFA biomarkers in soil samples at different stand ages. The average concentrations of total, bacterial, fungal, and actinomycete PLFAs in the surface soil initially decreased and then increased, before decreasing with the stand age in summer. The PLFA concentrations of major microbial groups were highest in year 9, with the total PLFA concentrations being 32.97% and 10.67% higher than those in years < 1 and 12, respectively. Higher microbial PLFA concentrations were detected in summer relative to autumn and in the surface relative to the subsurface soil. The highest ratios of Gram-positive to Gram-negative bacterial (G^?/G⁺) and fungal to bacterial (F/B) PLFAs were obtained in year 6, on average 76.09% higher than those at the other four stand ages. The soil environment was most stable in year 6, with no differences between other stand ages. Therefore, soil microbial community structure was strongly influenced by the stand age in year 6 only. The effect of stand age on soil G^?/G⁺ and microbial community structure varied with season and depth; there was little effect for F/B in the 20–40 cm soil layer. Principal component analysis revealed no correlations between microbial PLFA concentrations and total salinity in the soil; negative correlations were noted between soil pH and F/B in summer (P < 0.01), as well as between soil pH and fungal PLFA in autumn (P < 0.05). Moreover, microbial PLFA concentrations were correlated with soil organic matter (mean R = 0.7725), total nitrogen (mean R = 0.8296), total phosphorus (mean R = 0.8175), available nitrogen (mean R = 0.7458), and available phosphorus (mean R = 0.7795) (P < 0.01). On the whole, the soil ecosystem was most stable in year 6, while soil organic matter, nutrients, and microbial PLFA concentrations were maximal in year 9; thereafter, soil fertility indices and microbial concentrations decreased and soil quality declined gradually as the stand age increased. Therefore, farmers should reduce the application rate of fertilizers, especially compound or mixed fertilizers, in L. barbarum fields; organic or bacterial manure can be applied increasingly to improve the soil environment and prolong the economic life of L. barbarum.     

Heavy metal bioaccumulation by the organs of Phragmites australis (common reed) and their potential use as contamination indicators

The concentrations of heavy metals in the roots, rhizomes, stems and leaves of the aquatic macrophyte Phragmites australis (common reed), and in the corresponding water and sediment samples from the mouth area of the Imera Meridionale River (Sicily, Italy), were investigated to ascertain whether plant organs are characterized by differential accumulation, and to test the suitability of the various organs for heavy metal biomonitoring of water and soil. Heavy metals considered were Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn. Results showed that belowground organs were the primary areas of metal accumulation. In particular, metal concentrations in plant organs decreased in the order of root > rhizome ≥ leaf > stem. All four organs showed significant differences in concentration for Cr, Hg, Mn, Zn, thus suggesting low mobility from roots to rhizomes and to aboveground organs. Although the organs followed different decreasing trends of metal concentration, the trend Mn > Zn > Pb > Cu was found in each plant organ. Mn showed the highest concentrations in all organs whereas the lowest concentrations regarded Cd and Cr in the belowground and aboveground organs, respectively. The toxic threshold was exceeded by Cr in roots, rhizomes and leaves, Mn in roots and leaves, Ni in roots. The highest average concentrations were found as follows: Cd, Hg, Pb, Zn in root, Cr, Mn, Ni in sediment, Cu in water. Positive linear relationships were found between heavy metal concentrations in all plant organs and those in water and sediment, thus indicating the potential use of such organs for pollution monitoring of water and sediment. Advantages of using plant species as biomonitors, especially Phragmites australis, were also discussed.     

Metal accumulation and damage in rice (cv. Vialone nano) seedlings exposed to cadmium

The effect of exposure to increasing cadmium concentrations was analyzed in rice seedlings (cv. Vialone nano). The highest Cd accumulation was found in roots, mostly in the apoplastic environment. Cd taken up in cells led to an increase in sulfhydryl groups, the appearance of phytochelatins, and formation of electron-dense vacuolar inclusions. The metal-exposure inhibited root growth and also interfered with correct root morphogenesis, causing disordered division and abnormal and forward enlargement of epidermal and cortical cell layers in the apical region. Cd accumulation in shoots was lower than in roots. In leaf cells, there was neither a substantial increase in sulfhydryl groups nor the appearance of phytochelatins. Shoot growth was reduced and, differently from in roots, leaf cell enlargement was inhibited. Chloroplasts had lowered contents of chlorophyll and a reduced number of thylakoids, but underwent structural alterations only at the highest Cd concentration tested (250 μM). Photosynthetic activity was limited due to the curtailment of CO₂ availability caused by the greater resistance of Cd-exposed leaves. The damage suffered by seedlings worsened with the increase in Cd concentration, but was already evident at the lowest concentration examined (50 μM), showing that the cv. Vialone nano has a Cd-sensitivity higher than other rice cultivars.     

Effect of different proportion of sulphur treatments on the contents of glucosinolate in kale (Brassica oleracea var. acephala) commonly consumed in Republic of Korea

Kale (Brassica oleracea L. Acephala Group) is the rich source of medicinal value sulphur compounds, glucosinolates (GLSs). The aim of this study was to investigate the effect of different proportion of sulphur (S) supplementation levels on the accumulation of GLSs in the leaves of the kale cultivar ('TBC'). High performance liquid chromatography (HPLC) separation method guided to identify and quantify six GSLs including three aliphatic (progoitrin, sinigrin and gluconapin) and three indolyl (glucobrassicin, 4-methoxyglucobrassicin and neoglucobrasscin) respectively. Analysis of these distinct levels of S supplementation revealed that the accumulation of individual and total GLSs was directly proportional to the S concentration. The maximum levels of total GLSs (26.8 µmol/g DW) and glucobrassicin (9.98 µmol/g DW) were found in lower and upper parts of the leaves supplemented with 1 mM and 2 mM S, respectively. Interestingly, aliphatic GSLs were noted predominant in all the parts (50.1, 59.3 and 56% of total GSLs). Among the aliphatic and indolyl GSLs, sinigrin and glucobrassicin account 35.3 and 30.88% of the total GSLs. From this study, it is concluded that supply of S enhance the GSLs accumulation in kale.     

Chemotactic response of Ginseng bacterial soft-rot to Ginseng root exudates

Our purpose was to evaluate chemotactic response of Ginseng bacterial soft-rot to ginseng root exudates. The exudates of plant roots has a significant influence on the population changes of rhizosphere microorganisms and chemotaxis is an important way in which many pathogens sense the signals of host plants and invade the host plants. In this study, with the capillary method, we tested the chemotactic responses of Ginseng bacterial soft-rot for three ginseng roots exudates under four chemotactic parameters (concentration, temperature, pH and time). The results showed that the chemotatic response of the Ginseng bacterial soft-rot for the ginseng roots exudates at the water layer where pH = 7 and the concentration was 0.0125 mg/L reached its peak value under the circumstance that the exudates was cultivated for 60 min at 25 °C. The chemotatic ratios were respectively 124.89% and 89.44%. For the butanol extract layer and the petroleum ether faction at the concentration of 0.125 mg/L and the pH value at 7, the ginseng roots exudatess reached peak values at 25 °C and 30 °C and 60 min and 75 min respectively, and the chemotatic ratios were respectively 139.64% and101.87%, and 115.29% and 81.36%. The three ginseng roots exudates had positive effects for the chemotaxis of the Ginseng soft-rot bacteria, but the effect declined as the concentration increased.     

Preparation,characterization of silver phyto nanoparticles and their impact on growth potential of Lupinus termis L. seedlings

The current study reports rapid and easy method for synthesis of eco-friendly silver nanoparticles (AgNPs) using Coriandrum sativum leaves extract as a reducing and covering agent. The bio-reductive synthesis of AgNPs was monitored using a scanning double beam UV-vis spectrophotometer. Transmission electron microscopy (TEM) was used to characterize the morphology of AgNPs obtained from plant extracts. X-ray diffraction (XRD) patterns of AgNPs indicate that the structure of AgNPs is the face centered cubic structure of metallic silver. The surface morphology and topography of the AgNPs were examined by scanning electron microscopy and the energy dispersive spectrum revealed the presence of elemental silver in the sample. The silver phyto nanoparticles were collected from plant extract and tested growth potential and metabolic pattern in (Lupinus termis L.) seedlings upon exposure to different concentrations of AgNPs. The seedlings were exposed to various concentrations of (0, 0.1, 0.3 and 0.5 mg L^?1) AgNPs for ten days. Significant reduction in shoot and root elongation, shoot and root fresh weights, total chlorophyll and total protein contents were observed under the higher concentrations of AgNPs. Exposure to 0.5 mg L^?1 of AgNPs decreased sugar contents and caused significant foliar proline accumulation which considered as an indicator of the stressful effect of AgNPs on seedlings. AgNPs exposure resulted in a dose dependent decrease in different growth parameters and also caused metabolic disorders as evidenced by decreased carbohydrates and protein contents. Further studies needed to find out the efficacy, longevity and toxicity of AgNPs toward photosynthetic system and antioxidant parameters to improve the current investigation.     

Modeling studies on mono and binary component biosorption of phenol and cyanide from aqueous solution onto activated carbon derived from saw dust

Biosorption is an effective treatment method for the removal of phenol and cyanide from aqueous solution by saw dust activated carbon (SDAC). Batch experiments were achieved as a function of several experimental parameters, i.e. influence of biosorbent dose (5–60 g/L) contact time (2–40 h), pH (4–12), initial phenol concentration (100–1000 mg/L) and initial cyanide concentration (10–100 mg/L) and temperature (20–40 °C). The biosorption capacities of the biosorbent were detected as 178.85 mg/g for phenol with 300 mg/L of initial concentration and 0.82 mg/g for cyanide with 30 mg/L of initial concentration. The optimum pH is found to be 8 for phenol and 9 for cyanide biosorption. The mono component biosorption equilibrium data for both phenol and cyanide were well defined by Redlich–Peterson model and binary component adsorption equilibrium data well fitted by extended Freundlich model. The percentage removal of phenol and cyanide using SDAC was 66.67% and 73.33%, respectively. Equilibrium established within 30 h for phenol and 28 h for cyanide. Kinetic studies revealed that biosorption of phenol followed pseudo second order indicating adsorption through chemisorption and cyanide followed pseudo first order kinetic model indicating adsorption through physisorption. Thermodynamic studies parameters, i.e., enthalpy (Δh₀), entropy (ΔS₀) and Gibb’s free energy (ΔG₀) have also been considered for the system. Thermodynamic modeling studies revealed that the process of cyanide biosorption was endothermic and phenol biosorption was exothermic in nature.     

Evaluation of cytological and genetic effects of Tribulus terrestris fruit aqueous extract on cultured human lymphocytes

The current study was carried out to evaluate the genotoxic aspects of the aqueous extracts of the Tribulus terrestris fruits by comet assay and cytogenetic procedures conditions on cultured human peripheral blood lymphocyte. After the treatment of the lymphocytes with four concentrations of the aqueous fruit extract of T. terrestris (10, 20, 40 and 80 mg/L) for 24 h it was noticed that, the presence of micronuclei and/or chromosomal aberration were monitored and a significant increase of comet cells at high concentration of T. terrestris extract 80 mg/L. Also, this study showed that the presence of micronuclei, chromosomal aberration as a chromosomal gap, fragmentation, stickiness and necrotic cells were appeared and increased with high concentrations of T. terrestris fruits extract (40–80 mg/L). On the other hand, no significant difference was observed with the low concentration of the extract (10–20 mg/L) as compared with control. The current study refers to the ability of the extract of T. terrestris fruits to do damage in the target DNA at the higher concentrations. Thus, it could be considered that the aqueous extracts of the T. terrestris fruits have genotoxic effect in the therapeutic protocols if it used in high doses.     

Antibacterial activity of selected medicinal plants of northwest Pakistan traditionally used against mastitis in livestock

The present study aimed to investigate the efficacy of traditionally used anti-mastitis plants (Allium sativum, Bunium persicum, Oryza sativa and Triticum aestivum) in northwest Pakistan against bacterial pathogens. Selected plants were phytochemically screened for Alkaloids, Flavonoids, and Saponins and checked for in vitro antibacterial activity at concentration of 50 mg/ml against S. aureus, E. coli and K. pneumoniae by agar well diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration was determined against multidrug resistant bacteria using tube dilution method. All extracts were found to significantly inhibit (p < 0.01, p < 0.05) the activity against bacterial strains examined. Among phytochemicals, alkaloids of all tested antimastitis plants produced significantly higher inhibition zones against bacteria. The minimum inhibitory concentration and minimum bactericidal concentration of phytochemicals and crude methanolic extracts against tested bacterial strains ranged between 12.5–50 mg/ml and 25–50 mg/ml, respectively. Medicinal plants traditionally used against mastitis are therapeutically active against bacterial pathogens. A. sativum and B. persicum were found to be potential candidate species for the development of novel veterinary drugs with low cost and fewer side effects.     

Response of miscanthus to toxic cadmium applications during the period of maximum growth

Plants of miscanthus were grown in a Cd-free solution up to 1 month before heading and then were exposed to 0, 0.75, 1.5, 2.25 and 3 mg l⁻¹ cadmium for 36 days. All cadmium levels were toxic to miscanthus. Growth response was not dose-dependent and two toxicity thresholds were identified: one between 0 and 0.75 mg l⁻¹ Cd, the other between 2.25 and 3 mg l⁻¹ Cd. The former caused a biomass decrease by about 50%, whereas the latter completely inhibited growth and disrupted the mechanisms that restricted Cd translocation to the shoot. Growth of the aerial part was affected by cadmium more than that of the hypogeal one. Cadmium did not change the N concentration of different plant parts, but markedly reduced the N uptake of the plant, the N net uptake rate (NUR) and the N net translocation rate (NTR) from the rhizome to the aerial part. These two indexes equalled zero when plants ceased to grow. Otherwise, the Cd-NUR increased with Cd supply and the Cd-NTR from rhizome to aerial part showed the highest increment when plants did not grow at all. This suggests different uptake pathways for the two elements, active for nitrogen and passive for cadmium. The Cd concentration and the Cd content markedly increased with all Cd levels, following the order roots ≫ rhizome > culms > leaves. The Cd concentration and the Cd content of aerial organs increased with Cd supply, but increments were highest between 2.25 and 3 mg l⁻¹ Cd. The highest Cd concentrations were recorded in plants grown with 3 mg l⁻¹ Cd and were 41 and 122 mg kg⁻¹, respectively, for the aerial and the hypogeal plant parts. The hypogeal plant part retained most of the cadmium taken up from solution, accounting for approximately 87% of total plant cadmium with the three lower Cd levels, and for 73% with the highest one. The maximum Cd content of the entire plant was achieved with the two higher Cd levels and was approximately 4.7 mg, while the Cd content of the aerial part was highest with 3 mg l⁻¹ Cd (1.2 mg Cd per plant) and that of the hypogeal one with 2.25 mg l⁻¹ Cd (4 mg Cd per plant). The highest aerial content achieved in this experiment was 10-fold that obtained in a previous research when small-sized plants were exposed to the same Cd level.     

Levels of l-ascorbic acid and cadmium in the saphenous vein of patients with coronary artery disease are negatively correlated

BackgroundThe aim of this study was the simultaneous determination of levels of cadmium and l-ascorbic Acid (AA) in human saphenous vein (SV) used in coronary artery bypass grafting (CABG) and check whether there is a relationship between these levels.MethodsHuman SV were collected from 40 patients (20 men and 20 women; age, 40–75 years) at the time of routine coronary artery surgical revascularization. The concentration of cadmium in the tissue was determined according to the GF AAS—atomic absorption method. The concentration of AA was assayed in supernatant by FIA method with spectrophotometric detection.ResultsAA concentration (mean ± SD); men: 98,7 ± 13,18 μg/g tissue, women: 96,06 ± 11,98 μg/g tissue. Cadmium concentration(mean ± SD); men: 309 ± 103,71 ng/g tissue, women: 348,5 ± 255,71 ng/g tissue. Correlations among concentrations of AA and cadmium were insignificant negative in the group of men (Pearson r = −0,1504, p = 0,5269) and in the group women (Pearson r = −0339, p = 0144).ConclusionsNegative correlations among concentrations of AA and cadmium in human SV obtained in our study may indicate a protective effect of this vitamin in relation to toxic cadmium.     

Nitric oxide protects sour pummelo (Citrus grandis) seedlings against aluminum-induced inhibition of growth and photosynthesis

Limited data are available on the amelioration of nitric oxide (NO) on aluminum (Al)-toxicity. Sour pummelo (Citrus grandis) seedlings were irrigated for 18 weeks with nutrient solution containing 0 and 1.2 mM AlCl₃·6H₂O × 0 and 10 μM sodium nitroprusside (SNP, an NO donor). Under Al stress, SNP increased root phosphorus (P) and Al, but decreased shoot Al. Al decreased photosynthesis, maximum quantum yield of primary photochemistry (F_v/F_m) and total performance index (PI_tot,sbs), but increased inactivation of oxygen-evolving complex (OEC), K-band and relative variable fluorescence at I-steps (V_I). SNP alleviated Al-induced changes for all these parameters. SNP stimulated Al-induced secretion of malate and citrate by excised roots from Al-treated seedlings, while Al did not increase their contents in roots. Antioxidant system in leaves and roots was up- and down-regulated by Al, respectively. SNP prevented Al-induced accumulation of malondialdehyde (MDA) in roots and leaves. In conclusion, SNP alleviates Al-induced inhibition of growth and impairment of the whole photosynthetic electron transport chain. This occurs through increasing Al-immobilization and P level in roots and Al-induced secretion of malate and citrate from roots, and decreasing Al accumulation in shoots. Thus, the decrease of photosynthesis is prevented. Increased P level and Al-immobilization in roots through SNP may be effected through enhanced secretion of malate and citrate.