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591.

Ocimum basilicum L. var. purpurascens is an enriched reservoir of pharmaceutically important compounds with plenty of health and therapeutic attributes such as phenolic acids and anthocyanins. However, the inefficient production of aforementioned metabolites in wild has restricted its commercial utilization. Herein, commercially viable phytochemicals have been enhanced through elicitation of in-vitro cultures of O. basilicum using yeast extract.The impact of various concentrations (YE 1 mg/L,YE 10 mg/L, YE 25 mg/L, YE 50 mg/L, YE 100 mg/L, YE 200 mg/L and YE 400 mg/L) of yeast extract on biomass accumulation, phytochemical production, and antioxidant activities were assessed in callus cultures. Moderate concentration of yeast extract (100 mg/L) enhanced biomass accumulation i.e. fresh weight (FW 216.28 g/L) and dry weight (DW 15.49 g/L) up to 1.5 folds as compared to control (FW 167.14 g/L and DW 10.25 g/L). Similarly, yeast extract (100 mg/L) increased total phenolic and flavonoid contents as well as enhanced antioxidant activities such as ABTS (2,2 azinobis 3-ethylbenzthiazoline-6-sulphonic acid), FRAP (ferric reducing antioxidant power) and DPPH (2,2-diphenyl-1-picryhydrazyl). High performance liquid chromatography (HPLC) analysis was elucidated for further phytochemical investigation. HPLC analysis showed an increase of almost 1.9 folds as compared to control in rosmarinic acid (15.19 mg/g DW), chicoric acid (2.13 mg/g DW), peonidin (2.70 mg/g DW) and cyanidin (1.57 mg/g DW). Likewise, 1.8 fold and 2.4 folds increase was observed in eugenol essential oils (0.25 mg/g DW) and chavicol (0.037 mg/g DW), respectively. For cellular antioxidant activity, reactive oxygen specie or reactive nitogen specie (ROS/RNS) was induced in yeast cells and the effect of O. basilicum callus culture was further investigated in stressed yeast cells. A positive correlation exists between the antioxidant activities, TPC and TFC analysis. In short, these results showed that yeast extract could act as an efficient elicitor to enhance pharmacologically important metabolites in callus cultures of Ocimum basilicum.

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Abstract

Purpose

To evaluate the genotoxic effects of gold jewellery fumes and its association with GSTM1 and GSTT1 genetic polymorphisms.  相似文献   
594.
AbstractUntreated wastewater contains toxic amounts of heavy metals such as chromium (Cr), which poses a serious threat to the growth and physiology of plants when used in irrigation. Though, Cr is among the most widespread toxic trace elements found in agricultural soils due to various anthropogenic activities. To explore the interactive effects of micronutrients with amino acid chelators [iron-lysine (Fe-lys) and zinc-lysine (Zn-lys)], pot experiments were conducted in a controlled environment, using spinach (Spinacia oleracea L.) plant irrigated with tannery wastewater. S. oleracea was treated without Fe and Zn-lys (0 mg/L Zn-lys and 0 mg/L Fe-lys) and also treated with various combinations of (interactive application) Fe and Zn-lys (10 mg/L Zn-lys and 5 mg/L Fe-lys), when cultivated at different levels [0 (control) 33, 66 and 100%) of tannery wastewater in the soil having a toxic level of Cr in it. According to the results, we have found that, high concentration of Cr in the soil significantly (P < 0.05) reduced plant height, fresh biomass of roots and leaves, dry biomass of roots and leaves, root length, number of leaves, leaf area, total chlorophyll contents, carotenoid contents, transpiration rate (E), stomatal conductance (gs), net photosynthesis (PN), and water use efficiency (WUE) and the contents of Zn and Fe in the plant organs without foliar application of Zn and Fe-lys. Moreover, phytotoxicity of Cr increased malondialdehyde (MDA) contents in the plant organs (roots and leaves), which induced oxidative damage in S. oleracea manifested by the contents of hydrogen peroxide (H2O2) and membrane leakage. The negative effects of Cr toxicity could be overturned by Zn and Fe-lys application, which significantly (P < 0.05) increase plant growth, biomass, chlorophyll content, and gaseous exchange attributes by reducing oxidative stress (H2O2, MDA, EL) and increasing the activities of various antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) catalase (CAT) and ascorbate peroxidase (APX). Furthermore, the supplementation of Zn and Fe-lys increased the contents of essential nutrients (Fe and Zn) and decreased the content of Cr in all plant parts compared to the plants cultivated in tannery wastewater without application of Fe-lys. Taken together, foliar supplementation of Zn and Fe-lys alleviates Cr toxicity in S. oleracea by increased morpho-physiological attributes of the plants, decreased Cr contents and increased micronutrients uptake by the soil, and can be an effective in heavy metal toxicity remedial approach for other crops.Graphic abstract  相似文献   
595.

Herein, we presented the synthesis and application of sodium dodecylbenzenesulfonate–based silver nanoparticles (termed as SDBS-AgNPs). The SDBS reverse micelles (RMs) in ethanol was used as nanoreactor for green AgNPs synthesis. The size, structure, and shape of SDBS-AgNPs were well distinct by UV/visible (UV/Vis), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM) techniques. The SDBS-AgNPs were quite stable even at high temperature (80 °C), salt concentration (up to 300 μM), and wide pH range (2 to 12). Moreover, SDBS-AgNPs were found to be highly sensitive and selective colorimetric sensor for antihypertensive drug amlodipine (AML). The interaction of AML with SDBS-AgNPs resulted as a substantial increase in the absorbance and a prominent blue shift in wavelength from 426 to 400 nm. DLS results were further confirmed that the SDBS-AgNPs break into smaller sized particles. Similarly, FTIR results also verified the SDBS-AgNPs etching–based sensing of AML molecules due to the strong attraction by amine and carbonyl functional groups on the target drug. The proposed sensor exhibited linear response in the range of 0.001–200 μM (R2 = 0.9917) with limit of detection (LOD) and quantification (LOQ) of 0.161 and 0.49 μM, respectively. The probe remained selective against AML, even in the presence of equimolar interfering species (including other drugs and metal ions). Furthermore, findings proposed that the SDBS-AgNPs might be used as effective substitute to minimize infection severity by obstructing the biofilm formation against nosocomial and urinary tract infection (UTI) causing pathogens.

Graphical abstract

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596.
The partition and purification of α-amylase from a culture supernatant of Aspergillus oryzae CBS 819.72 was made in aqueous two-phase system (ATPS). According to bibliography and preliminary studies, the factors polyethylene glycol (PEG) molecular weight (MPEG) and concentration (CPEG), buffer type (BU) and concentration (CBU), temperature (T), salt nature (SALT) and concentration (CSALT), bioligand (BL) and concentration (CBL) and pH were investigated using a Plackett–Burman design to identify the factors affecting separation. Taking into consideration a simultaneous increase in enzyme recovery (RY) and purification factor (PF), the best performance of the system was obtained at 4 °C and pH 6 using PEG 8000 g/mol, citrate buffer, KCl and sucrose. Experimental Box–Behnken design together with the Response Surface Methodology (RSM) have been used to find optimum CPEG, CCitrate and CSALT. Quadratic models were predicted for PF and RY in the top phase and a better compromise between these two parameters can be found by superimposing the contour plots of PF and RY for 8% citrate. A region in the experimental space can be defined where the purification factor is always higher than 3 with yields exceeding 65%.  相似文献   
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BackgroundIron deficiency anemia (IDA) is the highest nutritional deficiency worldwide. It is a multifactorial disease, with a higher morbidity rate. TMPRSS6 polymorphisms importantly rs855791 is found to play an essential role in iron homeostasis in the human body. The rs855791 (T > C) polymorphism is highly associated with iron levels, and multiple blood parameters, leading to IDA. The role of TMPRSS6 rs855791 polymorphism and the significance of complete blood count (CBC) parameters in the pathogenesis of IDA is not yet studied in the Pakistani population.MethodsWe enrolled 113 cases and 136 controls to conduct a case control study. Complete blood count (CBC) and iron parameters were analyzed for association studies. PCR-RFLP based genotyping was performed.ResultsThe TMPRSS6 rs855791 (T > C) polymorphism is significantly associated with IDA pathogenesis as observed in the codominant model and recessive models (P < 0.05, OR: 1.5 and 95% CI: 0.9, 2.6, P < 0.05, OR: 0.5 and 95% CI: 0.2, 0.9 respectively). Elderly women among cases (30–49 years) were found to be more susceptible to IDA (P < 0.05, AOR: 2.1 and 95% CI: 1.0, 4.2). The most significant parameters associated with IDA were red blood cell count (RBC) and hematocrit (Hct%) (P < 0.05, AOR: 16.5, 95% CI: 7.6, 35.9 and P < 0.05, AOR: 10.1, 95% CI: 2.5, 41.6, respectively).ConclusionTMPRSS6 polymorphism at rs855791 (T > C) is significantly associated with IDA susceptibility in reproductive age women in Pakistan. Age, RBC count and Hct% are found to play an important role in IDA pathogenesis in our study population.  相似文献   
599.
N-cadherin (N-cad) is a calcium-dependent cell adhesion molecule which is present in the granulosa cells of the mouse ovarian follicle. This cell adhesion molecule has been implicated as a key modulator of follicular development. The regulators of N-cad mRNA levels in the ovary have not been identified. We have examined the ability of steroids to influence ovarian N-cad mRNA levels in vivo. Immature mice were injected with either progesterone, testosterone, 17β-estradiol, or 17α-estradiol. Only 17β-estradiol caused a rapid and significant increase in the ovarian N-cad mRNA levels. We speculate that this steroid is a major regulator of N-cad-mediated granulosa cell interactions in vivo. © 1995 Wiley-Liss, Inc.  相似文献   
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