Streptomyces Bioactive Metabolites Prevent Liver Cancer through Apoptosis, Inhibiting Oxidative Stress and Inflammatory Markers in Diethylnitrosamine-Induced Hepatocellular Carcinoma

A safe and effective treatment for liver cancer is still elusive despite all attempts. Biomolecules produced from natural products and their derivatives are potential sources of new anticancer medications. This study aimed to investigate the anticancer potential of a Streptomyces sp. bacterial extract against diethylnitrosamine (DEN)-induced liver cancer in Swiss albino mice and explore the underlying cellular and molecular mechanisms. The ethyl acetate extract of a Streptomyces sp. was screened for its potential anticancer activities against HepG-2 using the MTT assay, and the IC₅₀ was also determined. Gas chromatography-mass spectrometric analysis was used to identify the chemical constituents of the Streptomyces extract. Mice were administered DEN at the age of 2 weeks, and from week 32 until week 36 (4 weeks), they received two doses of Streptomyces extract (25 and 50 mg/kg body weight) orally daily. The Streptomyces extract contains 29 different compounds, according to the GC-MS analysis. The rate of HepG-2 growth was dramatically reduced by the Streptomyces extract. In the mice model. Streptomyces extract considerably lessened the negative effects of DEN on liver functions at both doses. Alpha-fetoprotein (AFP) levels were significantly (p < 0.001) decreased, and P53 mRNA expression was increased, both of which were signs that Streptomyces extract was suppressing carcinogenesis. This anticancer effect was also supported by histological analysis. Streptomyces extract therapy additionally stopped DEN-induced alterations in hepatic oxidative stress and enhanced antioxidant activity. Additionally, Streptomyces extract reduced DEN-induced inflammation, as shown by the decline in interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels. Additionally, the Streptomyces extract administration dramatically boosted Bax and caspase-3 levels while decreasing Bcl-2 expressions in the liver according to the Immunohistochemistry examination. In summary, Streptomyces extract is reported here as a potent chemopreventive agent against hepatocellular carcinoma through multiple mechanisms, including inhibiting oxidative stress, cell apoptosis, and inflammation.

Efficacy of licorice extract on the growth performance, carcass characteristics, blood indices and antioxidants capacity in broilers

Some studies have suggested that dietary medicinal plants or herbs may have a variety of biological functions such as anti-inflammatory, antiallergic, antifungal, antioxidative stress, and anticarcinogenic activities. The present study was undertaken to assess the incorporation of the extract of licorice supplementation on the growth performance, carcass yield, blood indices, and antioxidative capacity in broilers. Three hundred twenty unsexed one-day-old Ross 308 broiler chicks were allocated randomly into four groups. Chicks in each group were randomly subdivided into eight replicates of ten chicks. The first group received a basal diet and was considered a control. The respective groups received a basal diet supplemented with 1, 2, and 3 g licorice extract/kg diet. The obtained results indicated that supplementation of licorice extract to broiler chicks resulted in heavier BW and weight gain and a better feed conversion ratio during the experimental periods compared with the control group. However, feed consumption increased during the entire growing period. Supplementing the broiler's diet with licorice extract led to a higher value of erythrocytes, leukocytes, haemoglobin, plasma total protein, albumin, and antioxidant concentration and a low value in plasma cholesterol, triglycerides, uric acid, urea, and total cholesterol. It could be concluded that the dietary addition of licorice extracts 2 and 3 g licorice extract/kg diet improved broiler chicks' growth performance and physiological status.

Provenance effect on bioactive phytochemicals and nutritional and health benefits of the desert date Balanites aegyptiaca

Balanites aegyptiaca L. is a multipurpose tree distributed in Africa and Middle East. Several parts of B. aegyptiaca have been suggested to have medicinal uses. So far the effect of ecological origin on the nutritional values and biological activities of B. aegyptiaca genotypes is rarely investigated. Further, metabolic profiling and assessment of the functional food value of B. aegyptiaca leaves are far from complete. In this study, biological activities and profiling of primary and secondary metabolites were investigated in the leaves of five B. aegyptiaca provenances collected from Egypt, Sudan, Saudi Arabia, and Yemen. Interestingly, all provenances showed notable antidiabetic, antioxidant, antiprotozoal, antibacterial, antifungal, and anticancer activities. Hierarchical clustering analysis revealed significant variability in the concentrations of individual sugars, organic acids, amino acids, fatty acids, vitamins, phenolics, and minerals among the provenances and these variations were provenance dependent. Medina provenance showed the heights diphenylpicrylhydrazyl (DPPH) scavenging and antifungal activities and was the most powerful against embryonic kidney adenocarcinoma and urinary bladder carcinoma cells. The highest inhibition against Escherichia coli and colon carcinoma cells was observed by Sudan and Cairo provenances. El-Kharga and Yemen provenances showed the greatest activity against Trypanosoma cruzi and hepatocellular and urinary bladder carcinoma. Therefore, leaves of B. aegyptiaca possess good nutritive and biological capacities and might have potential applications in the food and medical industries. However, the strength of such activities is significantly affected by the provenance. PRACTICAL APPLICATIONS: According to the national Research Council (NRC) of United States, Balanites aegyptiaca L. is recognized among the 24 priority lost crops of Africa. B. aegyptiaca leaves contain considerable amounts of primary metabolites (e.g., sugars, EAAs, USFAs) and secondary (e.g., phenolic acids and flavonoids) metabolites, vitamins, and macro and microelements. The obvious existence of these nutritionally and medicinally related compounds supports the functional food value of B. aegyptiaca leaves. Moreover, the present results revealed that B. aegyptiaca is not only a foliage dietary plant, but also could be considered as a valuable source for neutraceuticals, which support its pharmacological value. So far, this is the first report to explore, in detail, the functional food value of B. aegyptiaca leaves by presenting a clear image about its metabolic profiling and biological activities, and how the provenance factor could affect these values.

Ocean acidification affects biological activities of seaweeds: A case study of Sargassum vulgare from Ischia volcanic CO2 vents

We utilized volcanic CO2 vents at Castello Aragonese off Ischia Island as a natural laboratory to investigate the effect of lowered pH/elevated CO2 on the bioactivities of extracts from fleshy brown algae Sargassum vulgare C. Agardh. We analysed the carbohydrate levels, antioxidant capacity, antibacterial, antifungal, antiprotozoal, anticancer properties and antimutagenic potential of the algae growing at the acidified site (pH ∼ 6.7) and those of algae growing at the nearby control site Lacco Ameno (pH∼8.1). The results of the present study show that the levels of polysaccharides fucoidan and alginate were higher in the algal population at acidified site. In general, extracts for the algal population from the acidified site showed a higher antioxidant capacity, antilipidperoxidation, antibacterial, antifungal, antiprotozoal, anticancer activities and antimutagenic potential compared to the control population. The increased bioactivity in acidified population could be due to elevated levels of bioactive compounds of algae and/or associated microbial communities. In this snapshot study, we performed bioactivity assays but did not characterize the chemistry and source of presumptive bioactive compounds. Nevertheless, the observed improvement in the medicinal properties of S. vulgare in the acidified oceans provides a promising basis for future marine drug discovery.

Differential responses of two cyanobacterial species to R-metalaxyl toxicity: Growth, photosynthesis and antioxidant analyses

Metalaxyl is a broad-spectrum chiral fungicide that used for the protection of plants, however extensive use of metalaxyl resulted in serious environmental problems. Thus, a study on the detoxification mechanism in algae/cyanobacteria and their ability for phycoremediation is highly recommended. Here, we investigated the physiological and biochemical responses of two cyanobacterial species; Anabaena laxa and Nostoc muscorum to R-metalaxyl toxicity as well as their ability as phycoremediators. Two different levels of R-metalaxyl, at mild (10 mg/L) and high dose (25 mg/L), were applied for one-week. We found that A. laxa absorbed and accumulated more intracellular R-metalaxyl compared to N. muscorum. R-metalaxyl, which triggered a dose-based reduction in cell growth, photosynthetic pigment content, and photosynthetic key enzymes' activities i.e., phosphoenolpyruvate carboxylase (PEPC) and ribulose‒1,5‒bisphosphate carboxylase/oxygenase (RuBisCo). These decreases were significantly less pronounced in A. laxa. On the other hand, R-metalaxyl significantly induced oxidative damage markers, e.g., H₂O₂ levels, lipid peroxidation (MDA), protein oxidation and NADPH oxidase activity. However, these increases were also lower in A. laxa compared to N. muscorum. To alleviate R-metalaxyl toxicity, A. laxa induced the polyphenols, flavonoids, tocopherols and glutathione (GSH) levels as well as peroxidase (POX), glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione-s-transferase (GST) enzyme activities. On the contrary, the significant induction of antioxidants in N. muscorum was restricted to ascorbate, catalase (CAT) and ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) enzyme activities. Although A. laxa accumulated more R-metalaxyl, it experienced less stress due to subsequent induction of antioxidants. Therefore, A. laxa may be a promising R-metalaxyl phycoremediator. Our results provided basic data for understanding the ecotoxicology of R-metalaxyl contamination in aquatic habitats and the toxicity indices among cyanobacteria.

Maize roots and shoots show distinct profiles of oxidative stress and antioxidant defense under heavy metal toxicity

Heavy metal accumulation in agricultural land causes crop production losses worldwide. Metal homeostasis within cells is tightly regulated. However, homeostasis breakdown leads to accumulation of reactive oxygen species (ROS). Overall plant fitness under stressful environment is determined by coordination between roots and shoots. But little is known about organ specific responses to heavy metals, whether it depends on the metal category (redox or non-redox reactive) and if these responses are associated with heavy metal accumulation in each organ or there are driven by other signals. Maize seedlings were subjected to sub-lethal concentrations of four metals (Zn, Ni, Cd and Cu) individually, and were quantified for growth, ABA level, and redox alterations in roots, mature leaves (L1,2) and young leaves (L3,4) at 14 and 21 days after sowing (DAS). The treatments caused significant increase in endogenous metal levels in all organs but to different degrees, where roots showed the highest levels. Biomass was significantly reduced under heavy metal stress. Although old leaves accumulated less heavy metal content than root, the reduction in their biomass (FW) was more pronounced. Metal exposure triggered ABA accumulation and stomatal closure mainly in older leaves, which consequently reduced photosynthesis. Heavy metals induced oxidative stress in the maize organs, but to different degrees. Tocopherols, polyphenols and flavonoids increased specifically in the shoot under Zn, Ni and Cu, while under Cd treatment they played a minor role. Under Cu and Cd stress, superoxide dismutase (SOD) and dehydroascorbate reductase (DHAR) activities were induced in the roots, however ascorbate peroxidase (APX) activity was only increased in the older leaves. Overall, it can be concluded that root and shoot organs specific responses to heavy metal toxicity are not only associated with heavy metal accumulation and they are specialized at the level of antioxidants to cope with.

4,4'-(((1E,5E)-pentane-1,5-diylidene)bis(azanylylidene))bis(1-dodecylpyridin-1-ium) bromide as a novel corrosion inhibitor in an acidic solution (part I)

The metal corrosion inhibition efficiency of a novel synthesized cationic gemini surfactant (SCGS), namely, 4,4'-(((1E,5E)-pentane-1,5-diylidene)bis(azanylylidene))bis (1-dodecylpyridin-1-ium) bromide, was studied in acidic medium by three techniques. The achieved results displayed the inhibition efficiency of the metal corrosion that was elevated by increasing both the SCGS's concentration and the applied temperature values. Furthermore, it was noticed that the charge transfer resistance value was elevated; however, the constant phase element was decreased with increasing the SCGS concentrations. The SCGS regards an excellent and mixed-type corrosion inhibitor. The adsorption of SCGS has agreed the Langmuir's adsorption isotherm and was related to physisorption and chemisorption.

Silicon dioxide nanoparticles ameliorate the phytotoxic hazards of aluminum in maize grown on acidic soil

Aluminum (Al) toxicity is a major constraint for crop production in acid soils. Therefore, looking for sustainable solutions to increase plant tolerance to Al toxicity is needed. Although several studies addressed the potential utilization of silica or silicon dioxide nanoparticles (SNPs) to ameliorate heavy metal phytotoxicity, the exact mechanisms underlying SNPs-induced stress tolerance are still unknown. The current study investigated how SNPs could mitigate Al toxicity in maize plants grown on acidic soil. The impact of Al alone or in combination with SNPs on Al accumulation and detoxification, plant growth, photosynthetic C assimilation and redox homeostasis has been investigated. Al accumulation in stressed-maize organs reduced their growth, decreased photosynthesis related parameters and increased production of reactive oxygen species, through induced NADPH oxidase and photorespiration activities, and cell damage. These effects were more pronounced in roots than in leaves. SNPs ameliorated Al toxicity at growth, physiological and oxidative damage levels. Co-application of SNPs significantly reduced the activities of the photorespiratory enzymes and NADPH oxidase. It stimulated the antioxidant defense systems at enzymatic (superoxide dismutase, catalase, ascorbate and glutathione peroxidases) and non-enzymatic (ascorbate, glutathione, polyphenols, flavonoids, tocopherols, and FRAP) levels. Moreover, SNPs increased organic acids accumulation and metal detoxification (i.e. glutathione-S-transferase activity) in roots, as a protective mechanism against Al toxicity. The SNPs induced-protective mechanisms was dependent on the applied Al concentration and acted in organ-specific manner. Overall, the current study suggests the promising application of SNPs as an innovative approach to mitigate Al phytotoxicity in acidic soils and provides a comprehensive view of the cellular and biochemical mechanisms underlying this mitigation capacity.

CO2 treatment improves the hypocholesterolemic and antioxidant properties of fenugreek seeds

A high level of serum cholesterol is a major cause of atherosclerosis. Fenugreek is a well-known hypocholesterolaemic agent with amazing phytochemical composition. Due to its impact on plant metabolism, CO₂ enrichment was tested as a strategy to support functional values in fenugreek seeds. Phytochemical composition and biological activities of three fenugreek cultivars (G2, G6 and G30) grown under ambient (aCO₂, 400 μmol mol^-1) and elevated CO₂ (eCO₂, 620 μmol mol^-1) were assessed. Applying eCO₂ improved physical parameters of fenugreek seeds, and enhanced their biological activities. A significant increase in hypocholesterolaemic potential, as indicated by inhibition of cholesterol micellar solubility and pancreatic lipase activity, was recorded. In addition, antioxidant, anti-lipid peroxidation and antibacterial activities were improved. These enhanced biological activities were accompanied by improved seed chemical composition at the primary and secondary metabolic levels. Therefore, eCO₂ treatment represents an efficient strategy to increase the hypocholesterolaemic, antioxidant and antibacterial activities of fenugreek seeds.

Physiological and biochemical responses to aluminum-induced oxidative stress in two cyanobacterial species

Phycoremediation technologies significantly contribute to solving serious problems induced by heavy metals accumulation in the aquatic systems. Here we studied the mechanisms underlying Al stress tolerance in two diazotrophic cyanobacterial species, to identify suitable species for Al phycoremediation. Al uptake as well as the physiological and biochemical responses of Anabaena laxa and Nostoc muscorum to 7 days Al exposure at two different concentrations i.e., mild (100 μM) and high dose (200 μM), were investigated. Our results revealed that A. laxa accumulated more Al, and it could acclimatize to long-term exposure of Al stress. Al induced a dose-dependent decrease in photosynthesis and its related parameters e.g., chlorophyll content (Chl a), phosphoenolpyruvate carboxylase (PEPC) and Ribulose‒1,5‒bisphosphate carboxylase/oxygenase (RuBisCo) activities. The affect was less pronounced in A. laxa than N. muscorum. Moreover, Al stress significantly increased cellular membrane damage as indicated by induced H₂O_2, lipid peroxidation, protein oxidation, and NADPH oxidase activity. However, these increases were lower in A. laxa compared to N. muscorum. To mitigate the impact of Al stress, A. laxa induced its antioxidant defense system by increasing polyphenols, flavonoids, tocopherols and glutathione levels as well as peroxidase (POX), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPX) enzymes activities. On the other hand, the antioxidant increases in N. muscorum were only limited to ascorbate (ASC) cycle. Overall, high biosorption/uptake capacity and efficient antioxidant defense system of A. laxa recommend its feasibility in the treatment of Al contaminated waters/soils.

Utilization of actinobacteria to enhance the production and quality of date palm (Phoenix dactylifera L.) fruits in a semi-arid environment

Actinobacteria have received much attention due to their capacity for plant growth promotion, a promising approach in sustainable development of agriculture. Date palm (Phoenix dactylifera L.) is an important crop, particularly in semi-arid regions of the world, due to the high nutritional and health-promoting values of its fruits. The present study was conducted to investigate the utilization of actinobacteria as an approach to support soil fertility and enhance production and functional food value of date palm fruits in a semi-arid environment. To achieve this purpose, actinobacterial strains were isolated from palm rhizosphere, characterized and screened for bioactivity. Then the potent isolates, based on plant growth promoting assays, were inoculated into the soil rhizosphere of five-target palms (Ajwa, Sokary, Khodry, Rashodia and Saffawy) before flowering and during fruiting stages in two successive seasons. Interestingly, the actinobacterial inoculants increased soil fertility and improved fruit yield of the tested palms. The treated date fruits accumulated higher levels of valuable phytochemicals such as sugars, organic acids, essential amino acids, unsaturated fatty acids, phenolic acids, flavonoids, vitamins and minerals, as compared with the untreated ones. Moreover, actinobacterial treatment induced the biological activities (antioxidant, antibacterial, antifungal and anticancer) of the produce dates. Conclusively, results presented herein suggest the promising application of actinobacteria for supporting the production and functional food value of date palms in semi-arid regions.

Vermicompost Supply Modifies Chemical Composition and Improves Nutritive and Medicinal Properties of Date Palm Fruits From Saudi Arabia

To meet the increased demand for phytochemicals, plant cultivation in soil amended with biofertilizers has been developed. Here, we aimed to use vermicompost as an environmentally safe biofertilizer to enhance the nutritive and medicinal value of five common cultivars of Saudi date palm; namely Phoenix dactylifera L. var. Ajwa, Hulwa, Ruthana, Sefri, and Luban. To determine changes in the fruit nutritive composition, primary metabolites, antioxidants, phenolic compounds and mineral profiles were analyzed in the fruits from non-fertilized and vermicompost-fertilized date palms. We also tested how changes in the fruit chemical compositions due to vermicompost fertilization affected their medicinal potentials. Applying vermicomposts generally increased primary metabolites, vitamins, and mineral content as well as the medicinal potential of the date palm fruits. This positive effect is possibly explained by the role of vermicomposts in improving soil health and fertility. Furthermore, clustering analyses and principal component analysis (PCA) indicated cultivar-specific responses. PCA analysis also revealed that the bioactivities of the date palm fruit extracts and their antioxidants tended to display correlated output values. One of the highly accumulated phenolic compounds, β-D-glucogallin, was extracted and purified from P. dactylifera L. var. Ajwa fruits and showed significant antioxidant, anticancer, antibacterial, antimutagenic, and antiprotozoal activities. Overall, applying vermicompost is an innovative approach to increase the nutritive quality and medicinal potential of date palm fruits.

Exploring the potential of actinomycetes in improving soil fertility and grain quality of economically important cereals

The search for environment-friendly, economical and healthy alternatives to agrochemicals tempted us to evaluate the potential of naturally occurring actinomycetes to improve soil properties, plant growth and photosynthesis, grain yield and chemical composition of economically important cereals (wheat, barley, oat, maize and sorghum). To this end, actinomycetes were isolated from soils of local cereals fields, then their biological activities, namely antibacterial, antiprotozoal, antioxidant, and phenolic and flavonoid contents were evaluated. The four most active isolates (9, 16, 24 and 26) were selected and used for enriching the soils until seed set. Each isolate was separately applied. Seeds of the selected cereals were grown in the actinomycete-enriched soils. The soils were analyzed for their electrical conductivity, pH values, total phenolics, organic matter and mineral content. At the vegetative stage, chlorophyll content and gas exchange rates were measured. Mature seeds were then harvested, the yield was evaluated and the seeds were analyzed for their primary and secondary metabolites. The selected isolates improved the grain yield in all tested cereals and most noticeably in barley and maize as compared to control counterparts. These positive effects were probably a result of increased carbon gain due to higher chlorophyll and photosynthetic rate. Isolate 26 showed the highest effect on grains composition profiles followed by the isolate 16. Phenolics and sugars of all grains increased by treatment with the tested isolates. Isolate 26 was the most effective in this regard. All isolates generally improved vitamins, amino acids and organic acids contents in grains. However, fatty acids profile showed a decrease in the content of all measured fatty acids by isolate 26 and an increase in the contents by isolate 16. These results emphasize the potential of actinomycete enrichment as an alternative to agrochemicals and strongly suggest that they can be used in organic farming.

Straw biochar increases the abundance of inorganic phosphate solubilizing bacterial community for better rape (Brassica napus) growth and phosphate uptake

The direct application of inorganic-phosphate-solubilizing bacteria (iPSBs) for improving the efficiency of phosphorus (P) use leads to a low rate of bacterial survival. Biochar is a good inoculum carrier for microbial survival, and diverse feedstocks can have different effects. We generated an iPSB community using seven selected iPSB strains with various phylogenic taxonomies and P-solubilizing abilities. Biochar was then inoculated with the iPSB community and applied to soil in pots seeded with rape (Brassica napus). Growth of the rape for four weeks and the effects of biochars produced from six raw feedstocks, rice straw, rice husks, soybean straw, peanut shells, corn cobs and wood, were compared. The synthetic iPSB community had a larger capacity to solubilize inorganic P and exude organic anions than any of the individual strains. The structure of the iPSB community was analyzed by high-throughput sequencing four weeks after inoculation. All seven iPSB strains were detected, dominated by Arthrobacter defluvii 06-OD12. The abundance of the iPSB community was significantly correlated with rape biomass, P content and P uptake (P < 0.05). The biochar amendments conferred 6.86-24.24% survival of the iPSB community, with the straw biochars conferring the highest survival. The available-P content of the biochar rather than soil pH was the dominant factor for iPSB community structure, suggesting that the biochar material was critical for the survival and functioning of the iPSB community. Our study demonstrates the feasibility of biochar-assisted iPSB improvement of crop growth and P uptake.

Microbacterium halophytorum sp. nov., a novel endophytic actinobacterium isolated from halophytes

Two actinobacterial strains, YJYP 303^T and YZYP 518, were isolated from two species of halophytes collected from the southern edge of the Gurbantunggut Desert. Cells were Gram-stain-positive, aerobic, short rods and without flagella. Growth of the two strains was found to occur at 4-44 °C, pH 6.0-12.0 and in the presence of up to 15 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains are associated with members of the genus Microbacterium. In the phylogenetic tree, the two strains shared a clade with Microbacterium halotolerans YIM 70130^T (97.58 % 16S rRNA gene sequence identity) and Microbacterium populi KCTC 29152^T (96.54 %). The average nucleotide identity values of strain YJYP 303^T and YZYP 518 to M. halotolerans YIM 70130^T were determined to be 79.97 and 80.03 %, respectively. The genomic DNA G+C contents of strains YJYP 303^T and YZYP 518 were 69.72 and 70.57 %, respectively. The major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The predominant respiratory quinones was MK-11, followed by MK-10 and MK-12. The muramic acid type of peptidoglycan was N-glycolyl. The whole-cell sugars were mannose, ribose, rhamnose, glucose, galactose and two unidentified sugars. The cell-wall amino acids were glutamic acid, ornithine, glycine and alanine. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and an unidentified glycolipid. On the basis of the evidence presented in this study, strains YJYP 303^T and YZYP 518 are characterized as members of a novel species in the genus Microbacterium, for which the name Microbacteriumhalophytorum sp. nov. is proposed. The type strain is YJYP 303^T (=CGMCC 1.16264^T=KCTC 49100^T).

Elevated CO2 induces a global metabolic change in basil (Ocimum basilicum L.) and peppermint (Mentha piperita L.) and improves their biological activity

Many studies have discussed the influence of elevated carbon dioxide (eCO₂) on modeling and crop plants. However, much less effort has been dedicated to herbal plants. In this study, a robust monitoring for the levels of 94 primary and secondary metabolites and minerals in two medicinal herbs, basil (Ocimum basilicum L.) and peppermint (Mentha piperita L.), grwon under both ambient (aCO₂, 360 ppm) and eCO₂ (620 ppm) was performed. We also assessed how the changes in herbal tissue chemistry affected their biological activity. Elevated CO₂ significantly increased herbal biomass, improved the rates of photosynthesis and dark respiration, and altered the tissue chemistry. Principal Component Analysis of the full data set revealed that eCO₂ induced a global change in the metabolomes of the two plants. Moreover, Hierarchical Clustering Analyses showed quantitative differences in the metabolic profiles of the two plants and in their responsiveness to eCO₂. Out of 94 metabolites, 38 and 31 significantly increased in basil and peppermint, respectively, as affected by eCO₂. Regardless of the plant species, the levels of non-structural carbohydrates, fumarate, glutamine, glutathione, ascorbate, phylloquinone (vitamin K1), anthocyanins and a majority of flavonoids and minerals were significantly improved by eCO₂. However, some metabolites tended to show species specificity. Interestingly, eCO₂ caused enhancement in antioxidant, antiprotozoal, anti-bacterial and anticancer (against urinary bladder carcinoma; T24P) activities in both plants, which was consequent with improvement in the levels of antioxidant metabolites such as glutathione, ascorbate and flavonoids. Therefore, this study suggests that the metabolic changes triggered by eCO₂ in the target herbal plants improved their biological activities.

Propionicimonas ferrireducens sp. nov., isolated from dissimilatory iron(III)-reducing microbial enrichment obtained from paddy soil

A novel strain, designated Y1A-10 4-9-1^T, with Gram-stain-positive and rod-shaped cells, was isolated from paddy soil in Yingtan, Jiangxi, China. Cells were 0.15-0.2 µm wide and 1.5-3.3 µm long. The optimal growth temperature was 30 °C and the optimal pH was 7.0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel strain is closely related to Propionicimonas paludicola JCM 11933^T (98.57 %). The genomic DNA G+C content was 63.9 mol%. The predominant menaquinone was MK-9(H4) and meso-diaminopimelic acid was present in the cell-wall peptidoglycan layer. The major polar lipids were diphosphatidylglycerol, one unidentified phospholipid and two unidentified lipids. The dominant cellular fatty acids detected were anteiso-C15 : 0 and iso-C16 : 0. The phylogenetic and phenotypic results supported that strain Y1A-10 4-9-1^T is a novel species of the genus Propionicimonas, for which the name Propionicimonas ferrireducens sp. nov. is proposed. The type strain is Y1A-10 4-9-1^T (=CCTCC AB 2016249^T=KCTC 15566^T=LMG 29810^T).

Saccharopolyspora deserti sp. nov., a novel halotolerant actinobacterium isolated from a desert

Strain SYSU D8010^T was isolated from a desert sand sample collected in Saudi Arabia. The taxonomic position of the isolate was investigated by the polyphasic taxonomic approach. The isolate was found to be Gram-positive and aerobic. The strain was able to grow at 14-40 °C, pH 5.0-9.0 and in the presence of up to 22 % (w/v) NaCl. Strain SYSU D8010^T contained meso-diaminopimelic acid as cell-wall diamino acid, and arabinose, fucose, galactose, glucose and rhamnose as the whole-cell sugars. The primary polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositolmannosides. Menaquinone MK-9(H4) was detected as the respiratory quinone; and anteiso-C17 : 0, iso-C16 : 0, iso-C15 : 0 and iso-C17 : 0 as the predominant fatty acids. Pairwise comparison of the 16S rRNA gene sequences indicated that strain SYSU D8010^T had a sequence similarity of 97.8 % to Saccharopolyspora halophila YIM 90500^T. The genomic DNA G+C content of strain SYSU D8010^T was determined to be 69.9 mol%. Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8010^T was determined to represent a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora deserti sp. nov. is proposed. The type strain of the species is SYSU D8010^T (=KCTC 39989^T=CPCC 204620^T).

Phenylobacterium deserti sp. nov., isolated from desert soil

A novel bacterial strain, designated YIM 73061^T, was isolated from the Cholistan desert in Punjab, Pakistan, and characterized by using a polyphasic taxonomic approach. 16S rRNA gene sequence analysis revealed the highest levels of sequence similarity with respect to Phenylobacterium conjunctum FWC21^T (97.6 %), Phenylobacterium lituiforme FaiI3^T (97.4 %), Phenylobacteriumcomposti 4T-6^T (97.0 %) and Phenylobacterium aquaticum W2-3-4^T (96.8 %). Cells were Gram-stain-negative, aerobic and motile rods that formed orange colonies. The strain was oxidase- and catalase-positive. Growth occurred at 20-40 °C (optimum, 30-37 °C) at pH 5.0-8.0 (optimum, pH 7.0) and with 0-1 % (w/v) NaCl (optimum, 0-0.5 %). The major cellular fatty acids (>10 %) were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. The polar lipid profile consisted of phosphatidylglycerol and four unidentified glycolipids. The major isoprenoid quinone was ubiquinone-10 (Q-10). The G+C content of the genomic DNA was 66.8 mol%. Strain YIM 73061^T showed low levels of DNA-DNA relatedness to P. conjunctum FWC21^T (27.2±2.6 %), P. lituiforme FaiI3^T (24.6±1.1 %) and P.composti 4T-6^T (18.4±3.1 %). On the basis of phylogenetic inference, chemotaxonomic characteristics and phenotypic data, strain YIM 73061^T should be classified as representing a novel species, for which the name Phenylobacterium deserti sp. nov. is proposed. The type strain is YIM 73061^T (=DSM 103871^T=CCTCC AB 2016297^T).

Identification, Bioactivity, and Productivity of Actinomycins from the Marine-Derived Streptomyces heliomycini

In the process of profiling the secondary metabolites of actinobacteria isolated from the Saudi coastal habitats for production of antibiotics and anti-cancer drugs, the cultures of strain WH1 that was identified as Streptomyces heliomycini exhibited strong antibacterial activity against Staphylococcus aureus. By means of MS and NMR techniques, the active compounds were characterized as actinomycins X0β, X2, and D, respectively. The research on the productivity of this strain for actinomycins revealed that the highest production of actinomycins X0β, X2, and D was reached in the medium MII within 5% salinity and pH 8.5. In this optimized condition, the fermentation titers of actinomycins X0β, X2, and D were 107.6 ± 4.2, 283.4 ± 75.3, and 458.0 ± 76.3 mg/L, respectively. All the three actinomycins X0β, X2, and D showed potent cytotoxicities against the MCF-7, K562, and A549 tumor cell lines, in which actinomycin X2 was the most active against the three tumor cell lines with the IC50 values of 0.8-1.8 nM. Both actinomycins X2 and D showed potent antibacterial activities against S. aureus and the methicillin-resistant S. aureus, Bacillus subtilis, and B. cereus and the actinomycin X2 was more potent.

Thermus amyloliquefaciens sp. nov., isolated from a hot spring sediment sample

A Gram-stain-negative, aerobic bacterium, designated strain YIM 77409T, was isolated from the Niujie hot spring in the Eryuan county of Dali, Yunnan province, south-west China. Cells of the strain were rod-shaped and colonies were yellow and circular. The strain grew at pH 6.0-8.0 (optimum, pH 7.0) and 50-70°C (optimum, 60-65°C). The predominant menaquinone was MK-8 and the DNA G+C content was 66.4 mol%. Major fatty acids (>10 %) were iso-C15 : 0 and iso-C17 : 0.The polar lipids consisted of one aminophospholipid, one phospholipid and two glycolipids. 16S rRNA gene sequence analysis showed that strain YIM 77409T formed a cluster with Thermus scotoductus DSM 8553T, Thermus antranikianii DSM 12462T, Thermus caliditerrae YIM 77925T and Thermus tengchongensis YIM 77924T, with highest 16S rRNA gene sequence similarity to T. scotoductus DSM 8553T (97.57%). However, DNA-DNA hybridization indicated that strain YIM 77409T should be viewed as a representative of a novel species, as there was only 30.6 ± 1.6% reassociation with T. scotoductus DSM 8553T. On the basis of the morphological and chemotaxonomic characteristics, as well as the genotypic data, it is proposed that strain YIM 77409T represents a novel species of the genus Thermus, with the name Thermus amyloliquefaciens sp. nov. The type strain is YIM 77409T ( = DSM 25898T = KCTC 32024T).

Frigoribacterium endophyticum sp. nov., an endophytic actinobacterium isolated from the root of Anabasis elatior (C. A. Mey.) Schischk

A novel endophytic actinobacterium, designated EGI 6500707(T), was isolated from the surface-sterilized root of a halophyte Anabasis elatior (C. A. Mey.) Schischk collected from Urumqi, Xinjiang province, north-west China, and characterized using a polyphasic approach. Cells were Gram-stain-positive, non-motile, short rods and produced white colonies. Growth occurred at 10-45 °C (optimum 25-30 °C), at pH 5-10 (optimum pH 8) and in presence of 0-4% (w/v) NaCl (optimum 0-3%). The predominant menaquinone was MK-9. The diagnostic phospholipids were diphosphatidylglycerol and phosphatidylglycerol. The major fatty acids were anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(16 : 0). The DNA G+C content of strain EGI 6500707(T) was 69.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain EGI 6500707(T) should be placed in the genus Frigoribacterium (family Microbacteriaceae , phylum Actinobacteria ), and that the novel strain exhibited the highest 16S rRNA gene sequence similarity to Frigoribacterium faeni JCM 11265(T) (99.1%) and Frigoribacterium mesophilum MSL-08(T) (96.5%). DNA-DNA relatedness between strain EGI 6500707(T) and F. faeni JCM 11265(T) was 47.2%. On the basis of phenotypic and chemotaxonomic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strain EGI 6500707(T) represents a novel species of the genus Frigoribacterium , for which the name Frigoribacterium endophyticum sp. nov. is proposed. The type strain is EGI 6500707(T) ( = JCM 30093(T) = KCTC 29493(T)).

Rhodococcus soli sp. nov., an actinobacterium isolated from soil using a resuscitative technique

A Gram-positive, aerobic, non-motile, non-spore forming strain, designated DSD51W(T), was isolated using a resuscitative technique from a soil sample collected from Kyoto park, Japan, and characterized by using a polyphasic approach. The morphological and chemotaxonomic properties of the isolate were typical of those of members of the genus Rhodococcus. Strain DSD51W(T) was found to form a coherent cluster with Rhodococcus hoagii ATCC 7005(T), Rhodococcus equi NBRC 101255(T), Rhodococcus defluvii Call(T) and Rhodococcus kunmingensis YIM 45607(T) as its closest phylogenetic neighbours in 16S rRNA gene sequence analysis. However, the DNA-DNA hybridization values with the above strains were 58.2 ± 2.2, 58.4 ± 1.9, 45.1 ± 1.4 and 40.3 ± 4.7 %, respectively. In combination with differences in physiological and biochemical properties, strain DSD51W(T) can be concluded to represent a novel species of the genus Rhodococcus, for which the name Rhodococcus soli sp. nov. is proposed, with the type strain DSD51W(T) (=KCTC 29259(T) = JCM 19627(T) = DSM 46662(T) = KACC 17838(T)).

Nesterenkonia rhizosphaerae sp. nov., an alkaliphilic actinobacterium isolated from rhizosphere soil in a saline-alkaline desert

An alkaliphilic actinobacterial strain, designated EGI 80099(T), was isolated from a rhizosphere soil sample of Reaumuria soongorica found in the desert soils of Fukang, Xinjiang, north-west China. Cells of strain EGI 80099(T) were Gram-stain-positive, non-motile, non-endospore-forming cocci. The predominant menaquinones were MK-7, MK-8 and MK-9. The major cellular fatty acids (>10 %) were anteiso-C15 : 0 and anteiso-C17 : 0. Analysis of the cell wall showed the presence of peptidoglycan of the type l-Lys-Gly-l-Glu, variation A4α. Cells of the isolate contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unknown phospholipid and an unidentified glycolipid as polar lipids. The genomic DNA G+C content was 63.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EGI 80099(T) belongs to the genus Nesterenkonia, sharing 95.68-97.37 % sequence similarities with the type strains of recognized species within this genus. DNA-DNA hybridization of strain EGI 80099(T) with the type strains of species that showed the highest sequence similarities, Nesterenkonia aethiopica DSM 17733(T) (97.37 %), Nesterenkonia flava CAAS 251(T) (97.23 %) and Nesterenkonia xinjiangensis YIM 70097(T) (97.02 %), gave relatedness values of 8.7-62.2 %. Data from DNA-DNA hybridizations and physiological and biochemical tests indicated that strain EGI 80099(T) represents a novel species of the genus Nesterenkonia, for which the name Nesterenkonia rhizosphaerae sp. nov. is proposed. The type strain is EGI 80099(T) ( = BCRC 16947(T) = JCM 19129(T)).

Streptomyces canchipurensis sp. nov., isolated from a limestone habitat

Hundung Limestone habitat, Manipur, India is an unexplored site for microbial diversity studies. Using polyphasic taxonomy, a Streptomyces strain, MBRL 172(T), has been characterized. The strain was found to show highest 16S rRNA gene sequence similarity with Streptomyces coeruleofuscus NBRC 12757(T) (99.2 %). The DNA relatedness between MBRL 172(T) and S. coeruleofuscus NBRC 12757(T), and between MBRL 172(T) and Streptomyces nogalater NBRC 13445(T), were 36.8 ± 4.4 and 52.5 ± 2.7 %, respectively. Strain MBRL 172(T) was found to contain LL-diaminopimelic acid as the diagnostic diamino acid and glucose, mannose and xylose as the major sugars in whole cell hydrolysates. The polar lipids in the cell membrane were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositolmannoside. The predominant menaquinones detected were MK-9(H6) and MK-9(H8). The cellular fatty acids identified were mainly saturated fatty acids: anteiso-C15:0, iso-C16:0 and iso-C15:0. Based on differences in the biochemical and molecular characteristics from its closest relatives, the strain can be proposed to represent a novel taxon in the genus Streptomyces, for which the name Streptomyces canchipurensis is proposed, with the type strain MBRL 172(T) (=JCM 17575(T) = KCTC 29105(T)).

Haladaptatus pallidirubidus sp. nov., a halophilic archaeon isolated from saline soil samples in Yunnan and Xinjiang, China

Two extremely halophilic archaea, designated YIM 90917 and YIM 93656(T), were isolated from saline soils in Yunnan province and Lup nur region in Xinjiang province, western China, respectively. Colonies of the two strains were observed to be pink-pigmented. The cells were found to be Gram-stain negative, coccoid and non-motile. The organisms were found to be aerobic and could grow in an NaCl range of 6-35 % (optimum 18 %), temperatures ranging from 25 to 50 °C (optimum 37-42 °C), pH range from 6.0-8.5 (optimum pH 7.0-7.5) and Mg(2+) range from 0 to 1.5 M (optimum 0.5-1.0 M); Mg(2+) was not necessary for growth. Cells were not observed to lyse in distilled water. Strains YIM 90917 and YIM 93656(T) showed the highest 16S rRNA gene sequence similarities to Haladaptatus cibarius JCM 15962(T) (97.6 and 97.9 %, respectively). In addition, the DNA-DNA hybridizations of strains YIM 90917 and YIM 93656(T) with type strains H. cibarius JCM 15962(T), Haladaptatus litoreus JCM 15771(T) and Haladaptatus paucihalophilus JCM 13897(T) were 37.2 and 38.2 %, 36.6 and 39.0 % and 27.9 and 27.7 %, respectively. The DNA G+C contents of strains YIM 90917 and YIM 93656(T) were determined to be 56.0 and 57.4 mol%. The major polar lipids of the two strains were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, sulfated mannosyl glucosyl diether and other four unidentified glycolipids. On the basis of physiological, chemotaxonomic data and phylogenetic analysis, the strains YIM 90917 and YIM 93656(T) can be classified as a novel species of the genus Haladaptatus, for which the name Haladaptatus pallidirubidus sp. nov. is proposed. The type strain is YIM 93656(T) (=JCM 17504(T) = CCTCC AB2010454(T)).

Eukaryotic microbial communities in hypersaline soils and sediments from the alkaline hypersaline Huama Lake as revealed by 454 pyrosequencing

In hypersaline ecosystems, microbial assemblages are structurally distinctive and play important roles in many microbiological and ecological processes. Here, eukaryotic microorganisms in hypersaline samples were investigated by 454 pyrosequencing of internal transcribed spacer (ITS) gene libraries. In total, 4,645, 1,677, and 5,912 reads were obtained from ITS libraries of waterlogged samples, salt crusts, and saline loess from the alkaline Huama Lake in Shaanxi, China. Analyses of pyrosequencing data revealed that the dominant genera were Dunaliella, Alternaria and Chlamydomonas, which dominated the microbial assemblages in the waterlogged sediments, the salt crusts and the saline loess from the lake banks, respectively. The various infrequent species were not commonly shared by the three types of samples, demonstrating that the eukaryotic microbial compositions of the different environments were distinct. However, the micro-eukaryotic assemblages associated with similar environmental conditions shared some components and were phylogenetically related. The eukaryotic microbial community composition was correlated with the pH value of the site (p = 0.001; r(2) = 0.99), but not with the concentration of total nitrogen or the inorganic ions investigated in this study. The results of this study demonstrated that the hypersaline ecosystems hosted surprisingly diverse eukaryotic microbial community.

Streptomyces fukangensis sp. nov., a novel alkaliphilic actinomycete isolated from a saline-alkaline soil

An alkaliphilic actinobacterium, designated EGI 80050(T), was isolated from a desert soil sample of Xinjiang, north-west China, and characterized by a polyphasic approach. The isolate was observed to produce purple orange-yellow aerial mycelium and dark orange-yellow substrate mycelium on yeast extract-malt extract agar medium. Whole-cell hydrolysates of strain EGI 80050(T) were found to contain LL-diaminopimelic acid as the diagnostic diamino acid, and galactose, glucose, rhamnose and mannose as the main sugars. The major fatty acids identified were C16:0-iso (36.8 %), C15:0-anteiso (17.3 %), 15:0-iso (13.2 %) and 14:0-iso (10.5 %). The predominant menaquinones detected were MK-9(H6) and MK-9(H8), while the characteristic polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, phosphatidylmethylethanolamine and three unknown phospholipids. The G+C content of the genomic DNA was determined to be 67.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences affiliated the strain EGI 80050(T) to the genus Streptomyces. Levels of 16 rRNA gene sequence similarities between strain EGI 80050(T) and Streptomyces candidus NRRL ISP-5141(T), Streptomyces cremeus NBRC 12760(T), Streptomyces spiroverticillatus NBRC 12821(T), Streptomyces violaceorectus NBRC 13102(T), Streptomyces cinereoruber subsp. cinereoruber NBRC 12756(T) were 96.7, 96.6, 96.6, 96.6 and 96.6 %, respectively. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain EGI 80050(T) is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces fukangensis sp. nov. (type strain EGI 80050(T) = BCRC 16945(T) = JCM 19127(T)) is proposed.