Efficacy of Sterculia diversifolia Leaf Extracts: Volatile Compounds, Antioxidant and Anti-Inflammatory Activity, and Green Synthesis of Potential Antibacterial Silver Nanoparticles.

Sterculia diversifolia, widely distributed in Jordan as an ornamental plant, is a synonoum for Brachychiton populneus. Phytochemical studies examining the volatile chemicals in Sterculia diversifolia leaves are limited, despite the rising demand for their numerous applications. Furthermore, it was only recently that a report described the friendly synthesis of silver nanoparticles (AgNPs) using aqueous extract derived from Brachychiton populneus leaves. Therefore, AgNPs were produced using either aqueous plant extracts (AgWPE) or ethanolic plant extracts (AgEPE), and Shimadzu GC-MS equipment was used to detect volatile compounds in the ethanolic leaf extracts. GC-MS profile of leaf ethanolic extracts of the Jordanian chemotypes of S. diversifolia revealed the existence of major components: (3ß)-Lup-20(29)-en-3-ol acetate (30.97%) and 1-octadecyne (24.88). Other compounds are squalene (7.19%), germanicol (6.23), dl-α-tocopherol (5.24), heptacosane (4.41), phytol (3.54) and pentacosane (2.89). According to published studies, these reported chemicals have numerous uses, including as animal feed, vitamin precursors, possible eco-friendly herbicides, antioxidants, and anti-inflammatory agents. Aqueous extracts of S. diversifolia leaves had total phenolic of 5.33 mg GAE/g extract and flavonoid contents of 64.88 mg QE/g extract, respectively. The results indicated the contribution of phenolic and flavonoids to this plant's anti-inflammatory and antioxidant properties. The reduction in AgNO3 to AgNPs using S. diversifolia leaf extracts was confirmed by the change in solution color from colorless to dark black. Further characterization was attempted by X-ray diffraction, Malvern zeta-sizer and scanning electron microscope. The efficacy of synthesized Ag nanoparticles using aqueous or ethanolic plant extract of S. diversifolia against the Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus showed appreciable activity at 25 µg/mL concentration compared to the source plant extracts.

Effect of various abiotic stressors on some biochemical indices of Lepidium sativum plants.

In this study, the regulation of ascorbate peroxidase (APX) specific activity, anthocyanin, carotenoid, hydrogen peroxide, lipid peroxidation, and protein levels in cress leaves in response to different abiotic stresses were investigated. The total APX specific activity was significantly elevated after 9 days of drought treatment, short-term (2 h) exposure to 10, 100 and 370 µE of light, long-term exposure (at least 6 days) to 100 mM NaCl versus the specific APX activity in the controls. Furthermore, a significant change in total APX activity was detected in response to treatment with different temperatures; this change was an early response to 4 °C and 30 °C for a maximum of 4 h, while short-term exposure to 35 °C did not change total APX activity. The results of the present study revealed that plants have a wide range of mechanisms to cope with different stresses that possibly involve morphological changes. The results indicated that Lepidium sativum plants launch common protective pathways only under drought, salinity and high light stresses, while other protective mechanisms/strategies could be responsible for increasing the plants tolerance towards temperature and low light. Future studies will investigate changes in the photosynthetic quantum yield and specific target metabolites, proteins, and nonenzymatic antioxidants.

Bacterial Quality of Urinary Tract Infections in Diabetic and Non Diabetics of the Population of Ma'an Province, Jordan.

BACKGROUND AND OBJECTIVE: The patients with Diabetes Mellitus (DM) have malfunction in bladder which prompt urine accumulation in its pool which serves a decent situation to the microbes to be develop and cause Urinary Tract Infection (UTI). The UTI is the most infectious disease that affects both males and females. This study was designed to detect the bacterial species responsible for UTI in both diabetic and non-diabetic patients in Ma'an province, Jordan. MATERIALS AND METHODS: One hundred sixteen urine samples were investigated to determine UTI-causing bacteria. These samples distributed unequally between diabetic male (12) and diabetic female (25) and also non-diabetic male (13) and non-diabetic female (66). RESULTS: It was observed that E. coli is responsible for large proportion (44.8%) of UTI in both diabetic (15.5%) and non-diabetic (29.3%) patients. This study showed inequality in the bacterial species that were isolated from both diabetic and non-diabetic samples. However, five bacterial species including E. aerogenes, E. cloacae, C. freundii, A. baumannii and B. subtilis did not exist in all diabetic samples. Treatment of UTI in both diabetic and non-diabetic patients with chloramphenicol (30 µg), ciprofloxacin (5 µg) and vancomycin (30 µg) resulted in more favorability than other antibiotics. At the same time cephalothin (30 µg) was not recommended. CONCLUSION: Escherichia coli was the prevailing bacterial infections among those which were isolated from patients with UTI. Certain forms of bacterial infections inclined to be extra common in diabetic patients than others and other infections may be more severe in people with diabetics than in non diabetics.

Kinetics of retrograde signalling initiation in the high light response of Arabidopsis thaliana.

High light acclimation depends on retrograde control of nuclear gene expression. Retrograde regulation uses multiple signalling pathways and thus exploits signal patterns. To maximally challenge the acclimation system, Arabidopsis thaliana plants were either adapted to 8 (low light (L-light)) or 80 µmol quanta m(-2) s(-1) (normal light (N-light)) and subsequently exposed to a 100- and 10-fold light intensity increase, respectively, to high light (H-light, 800 µmol quanta m(-2) s(-1)), for up to 6 h. Both L → H- and N → H-light plants efficiently regulated CO2 assimilation to a constant level without apparent damage and inhibition. This experimental set-up was scrutinized for time-dependent regulation and efficiency of adjustment. Transcriptome profiles revealed that N-light and L-light plants differentially accumulated 2119 transcripts. After 6 h in H-light, only 205 remained differently regulated between the L → H- and N → H-light plants, indicating efficient regulation allowing the plants to reach a similar transcriptome state. Time-dependent analysis of transcripts as markers for signalling pathways, and of metabolites and hormones as possibly involved transmitters, suggests that oxylipins such as oxophytodienoic acid and jasmonic acid, metabolites and redox cues predominantly control the acclimation response, whereas abscisic acid, salicylic acid and auxins play an insignificant or minor role.

Fast retrograde signaling in response to high light involves metabolite export, MITOGEN-ACTIVATED PROTEIN KINASE6, and AP2/ERF transcription factors in Arabidopsis.

Regulation of the expression of nuclear genes encoding chloroplast proteins allows for metabolic adjustment in response to changing environmental conditions. This regulation is linked to retrograde signals that transmit information on the metabolic state of the chloroplast to the nucleus. Transcripts of several APETALA2/ETHYLENE RESPONSE FACTOR transcription factors (AP2/ERF-TFs) were found to respond within 10 min after transfer of low-light-acclimated Arabidopsis thaliana plants to high light. Initiation of this transcriptional response was completed within 1 min after transfer to high light. The fast responses of four AP2/ERF genes, ERF6, RRTF1, ERF104, and ERF105, were entirely deregulated in triose phosphate/phosphate translocator (tpt) mutants. Similarly, activation of MITOGEN-ACTIVATED PROTEIN KINASE6 (MPK6) was upregulated after 1 min in the wild type but not in the tpt mutant. Based on this, together with altered transcript regulation in mpk6 and erf6 mutants, a retrograde signal transmission model is proposed starting with metabolite export through the triose phosphate/phosphate translocator with subsequent MPK6 activation leading to initiation of AP2/ERF-TF gene expression and other downstream gene targets. The results show that operational retrograde signaling in response to high light involves a metabolite-linked pathway in addition to previously described redox and hormonal pathways.

Efficient acclimation of the chloroplast antioxidant defence of Arabidopsis thaliana leaves in response to a 10- or 100-fold light increment and the possible involvement of retrograde signals.

Chloroplasts are equipped with a nuclear-encoded antioxidant defence system the components of which are usually expressed at high transcript and activity levels. To significantly challenge the chloroplast antioxidant system, Arabidopsis thaliana plants, acclimated to extremely low light slightly above the light compensation point or to normal growth chamber light, were moved to high light corresponding to a 100- and 10-fold light jump, for 6 h and 24 h in order to observe the responses of the water-water cycle at the transcript, protein, enzyme activity, and metabolite levels. The plants coped efficiently with the high light regime and the photoinhibition was fully reversible. Reactive oxygen species (ROS), glutathione and ascorbate levels as well as redox states, respectively, revealed no particular oxidative stress in low-light-acclimated plants transferred to 100-fold excess light. Strong regulation of the water-water cycle enzymes at the transcript level was only partly reflected at the protein and activity levels. In general, low light plants had higher stromal (sAPX) and thylakoid ascorbate peroxidase (tAPX), dehydroascorbate reductase (DHAR), and CuZn superoxide dismutase (CuZnSOD) protein contents than normal light-grown plants. Mutants defective in components relevant for retrograde signalling, namely stn7, ex1, tpt1, and a mutant expressing E .coli catalase in the chloroplast showed unaltered transcriptional responses of water-water cycle enzymes. These findings, together with the response of marker transcripts, indicate that abscisic acid is not involved and that the plastoquinone redox state and reactive oxygen species do not play a major role in regulating the transcriptional response at t=6 h, while other marker transcripts suggest a major role for reductive power, metabolites, and lipids as signals for the response of the water-water cycle.