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This study was conducted to isolate and identify thermophilic and thermotolerant bacteria from Jordanian hot springs and to determine hydrolytic, antimicrobial, and anticancer activities of the isolates. Thirty bacterial isolates were recovered from water samples of five main local hot springs. Nineteen of the isolated colonies were light yellow and circular to rhizoid on nutrient agar; cells were Gram-positive, endospore-forming, and rod-shaped. Eleven isolates were Gram-negative non-spore forming rods. It was found that 21 isolates met the criteria of moderate thermophiles; all isolates were grown aerobically (JA5 was facultative anaerobes) at 40-60 °C, pH 6-9, and 0-4% salt concentration and most of these isolates were reacted positively with catalase and oxidase. The remaining nine isolates were thermotolerant. Depending on the 16S rRNA gene sequences of the isolates, it was found that 19 thermophilic isolates have 97-100% sequence homology to the genus Bacillus; eight isolates were closely related to the thermophilic genus Geobacillus showing 97-100% homology to G. stearothermophilus ATCC 7953. The isolate JM2 shares 99% sequence homology with Thermomonas hydrothermalis. Remarkably, it was found that the 16S rDNA sequence of isolate JZ9 were highly similar (99% identity) to the thermophilic bacterium Caldimonas hydrothermale. To our knowledge, this is the first record of Caldimonas isolation from Jordanian hot springs. A wide spectrum of hydrolytic activities for protease, lipase, xylanase, cellulase, amylase, and pectinase was detected from the obtained isolates. It was found that JM1, JS3, and JZ11 isolates produced all tested enzymatic activities. Antimicrobial activities were only exhibited by three isolates (thermophilic JH1 and JM11 and thermotolerant JS3). Results indicated that three thermophilic Bacillus isolates (JA2, JM11, and JM12) produced selective cytotoxicity against human leukemia cell line K562. Therefore, many of the obtained isolates in this study can be considered as a promising source of effective agents that may be used for medical, pharmaceutical, and industrial purposes. [ABSTRACT FROM AUTHOR]

Cancer is a worldwide health problem and is the second leading cause of death after heart disease. Due to the high cost and severe side effects associated with chemotherapy treatments, natural products with anticancer therapeutic potential may play a promising role in anticancer therapy. The purpose of this study was to investigate the cytotoxic and apoptotic characteristics of the aqueous Drimia maritima bulb extract on Caco-2 and COLO-205 colorectal cancer cells. In order to reach such a purpose, the chemical composition was examined using the GC-MS method, and the selective antiproliferative effect was determined in colon cancer cell lines in normal gingival fibroblasts. The intracellular ROS, mitochondrial membrane potential, and gene expression changes in selected genes (CASP8, TNF-α, and IL-6 genes) were assessed to determine the molecular mechanism of the antitumor effect of the extract. GC-MS results revealed the presence of fifty-seven compounds, and Proscillaridin A was the predominant secondary metabolite in the extract. The IC50 of D. maritima bulb extract on Caco-2, COLO-205, and the normal human gingival fibroblasts were obtained at 0.9 µg/mL, 2.3 µg/mL, and 13.1 µg/mL, respectively. The apoptotic effect assay indicated that the bulb extract induced apoptosis in both colon cancer cell lines. D. maritima bulb extract was only able to induce statistically significant ROS levels in COLO-205 cells in a dose-dependent manner. The mitochondrial membrane potential (MMP) revealed a significant decrease in the MMP of Caco-2 and COLO-205 to various concentrations of the bulb extract. At the molecular level, RT-qPCR was used to assess gene expression of CASP8, TNF-α, and IL-6 genes in Caco-2 and COLO-205 cancer cells. The results showed that the expression of pro-inflammatory genes TNF-α and IL-6 were upregulated. The apoptotic initiator gene CASP8 was also upregulated in the Caco-2 cell line and did not reach significance in COLO-205 cells. These results lead to the conclusion that D. maritima extract induced cell death in both cell lines and may have the potential to be used in CRC therapy in the future. [ABSTRACT FROM AUTHOR]

Domestication process and the subsequent breeding may result in a genetic mutation and selection pressures that possibly contributed to the emergence of two phenotypes of barley spikelets, namely six-row and two-row barley. The present study used microsatellite genetic markers to investigate the population genetics of a selected set of accessions of domesticated barley representing different populations of Jordan, to identify a signature of selection resulted from domestication process. Genomic and statistical approaches, such as the analysis of molecular variance (AMOVA) and the so-called hierarchical "outlier" tests, were utilized to identify signatures of selection. Generally, there was a high level of polymorphisms in all the studied populations, which ranged from 19.23 for Ramtha to 69.23 (%) for Zarga, with an average of 53.61 (%). The average number of allele per locus for the entire sample set was of 9.346 and it ranged 2 occurring at [(Bmag0136), (EBmac0970_a), (EBmac0970_c) loci], to 27 at (Bmac0040) locus. The results of AMOVA showed that the main portion (~72%) of total diversity was attributed to differentiations within populations. Other portions of diversity (11.040%) were explained by the diversity among populations. As revealed by the hierarchical outlier tests and AMOVA results, 9 microsatellites were identified to be under possible selection pressures, possibly indicates that these loci were important in the past improvement of barley by early cultivators. In conclusion, the present study shows that barley landraces of Jordan possess high levels of genetic diversity and allelic richness that could be utilized in barley improvement and breeding program. [ABSTRACT FROM AUTHOR]

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The investigation of Bacillus thuringiensis (Bt) in 16 forest soil samples from Ajloun, northern Jordan, involved the isolation of 23 isolates toxic to the third instar dipteran larvae of Drosophila melanogaster and 7 isolates toxic to the third instar lepidopteran larvae of Ephestia kuehniella. The highest viable count of Bt was found in Ebeen forest soils (14.24 × 107 CFU g-1), and the lowest viable count was found in Rasoun forest soils. The lethal concentration (LC50) of Bt isolates indicated a variation in their toxicity to D. melanogaster and E. kuehniella larvae, with lower LC50 values for D. melanogaster suggesting that D. melanogaster larvae are more susceptible to Bt toxins than E. kuehniella larvae. Serotyping of the 23 isolates toxic to D. melanogaster revealed that they belonged to 5 serotypes, including israelensis, kenyae, kurstaki, malaysiensis, and morrisoni. Serotype israelensis was the most dominant. The isolates toxic to E. kuehniella larvae belonged to serotype kurstaki and produced both bipyramidal and cuboidal parasporal crystals. It was observed that isolates producing toxic spherical parasporal crystals were the most abundant in the forest soils. Hydrolytic activities of Bt isolates recovered from forests were varied due to differences in their enzyme productivity. Most isolates had carboxymethylcellulase, amylase, lipase, and gelatinase activity, while pectinase activity was observed in only a few isolates. Maceration activity of the isolates to potato samples was more frequent than to carrot samples. The larvicidal and hydrolytic activities of tested Bt isolates demonstrated that a forest environment can be categorized as a rich source for Bt isolates that can be used in biological control and plant residue biodegradation. As a result, it is expected that Bt recovered from forests can be used to increase soil fertility and to enhance plant growth as well as productivity. [ABSTRACT FROM AUTHOR]

Highly dispersed nanoporous Au rods have been prepared from arc melted Ag70Au30 alloy using site-selective electrochemical potential controlled dealloying method followed by Au anodizing process. The microstructure studies using scanning electron microscope and atomic force microscope indicate that selective removal of Ag from the Ag70Au30, precursor results in the formation of bi-continuous three-dimensional network structures with uniform pores and Au ligaments diameter of 6 nm. The noticeable features present in the optical studies of highly dispersed nanoporous Au rods using UV—Vis spectroscopy are two absorption bands peaking at 477 and 546 nm with overlapping of these bands at 520 nm. The antimicrobial testing by Agar well diffusion method reveals that the dispersed porous Au rods have greater inhibitory effect against both Gram-positive and Gram-negative bacterial strains. The results obtained provide opportunities to design and manipulate nanoporous Au rods at atomic level to achieve antimicrobial efficacy for biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Phenolic compounds (polyphenols) are common plant secondary metabolites playing different roles in plants, and some of these vegetables and correlated fruits--figs, grapes, pomegranates, olives, date palms, etc.--contain remarkable and diversified amounts of these substances. In addition, polyphenols are reported to show positive effects for human health, because of their antioxidant behavior. Figs are an excellent source of polyphenols with highest concentrations of proanthocyanidins. Actually, figs contain higher amounts of polyphenols than red wine and tea. Objective: Antioxidant activity of several flavonoids (a group of polyphenols) in figs is higher than that of, vitamin C, glutathione, or vitamin E. Pomegranates contain very high levels of polyphenols as compared to other fruits and vegetables. It is used in folklore medicine for the treatment of various diseases, such as hepatic damage, snakebite, ulcer, etc. Method: The health-positive potential of pomegranate fruit has been mainly attributed to ellagitannins, the predominant class of phenolics in pomegoxidation. Results: The chief phenolic compound found in fresh olive is the bitter secoiridoid oleuropein.. Conclusions: Processing of table olive decreases levels of oleuropein with correlated increases in the hydrolysis of hydroxytyrosol and tyrosol. Many of the health benefits reported for olives are thought to be associated with the levels of hydroxytyrosol. Date palm represents a staple food in most of the Arabian countries and is commonly consumed in several parts of the world. Highlights: Numerous researches revealed the antibacterial, anti-hyperlipidemic, hepatoprotective, antimutagenic, and nephroprotective activity of date fruits, with reported anticancer and anti-fungal features. [ABSTRACT FROM AUTHOR]

Background: The presence of phenolic acids in edible products for human consumption is considered in relation to the production of odorant substances, with a variety of different aromas. Objective: Phenolic substances anthocyanidins, anthocyanins, flavanols, flavones and isoflavones, flavones, flavonols, etc. - are extremely interesting as flavor additives, anti-aging ormaturing agents, and color and aroma enhancers. Method: The connection between flavoring properties on one hand and the presence of phenolic compounds on the other can be discussed in terms of food acceptance by consumers, especially with relation to the "Mediterranean Diet" lifestyle. Results: The health perspectives of these and other food products related to Mediterranean Diet should be evaluated in the geographical ambit of the Mediterranean Basin, including several particular food and vegetable preparations - herbs and medicinal plants - of the Middle East. Conclusions: The aim of this paper is to give a presentation on these specialties in relation to Jordan. Highlights: Medicinal herbs have interesting health properties against digestive problems, parasitic worms, liver diseases, diabetes, skin problems, nervous, cardiocirculatory, and respiratory diseases. [ABSTRACT FROM AUTHOR]