Catalytic Transformation of Triglycerides to Biodiesel with SiO2-SO3H and Quaternary Ammonium Salts in Toluene or DMSO.

SiO2-SO3H, with a surface area of 115 m2·g-1, pore volumes of 0.38 cm3·g-1 and 1.32 mmol H+/g, was used as a transesterification catalyst. Triglycerides of waste cooking oil reacted with methanol in refluxing toluene to yield mixtures of diglycerides, monoglycerides and fatty acid methyl esters (FAMEs) in the presence of 20% (w/w) catalyst/oil using the hydrophilic sulfonated silica (SiO2-SO3H) catalyst alone or with the addition of 10% (w/w) co-catalyst/oil [(Bun4N)(BF4) or Aliquat 336]. The addition of the ammonium salts to the catalyst lead to a decrease in the amounts of diglycerides in the products, but the concentrations of monoglycerides increased. Mixtures of (Bun4N)(BF4)/catalyst were superior to catalyst alone or Aliquat 336/catalyst for promoting the production of mixtures with high concentrations of FAMEs. The same experiments were repeated using DMSO as the solvent. The use of the more polar solvent resulted in excellent conversion of the triglycerides to FAME esters with all three-catalyst media. A simplified mechanism is presented to account for the experimental results.

Temperature Dependence of the Electrical Properties of Na2Ti3O7/Na2Ti6O13/POMA Composites.

The temperature dependence of the electrical properties of composites formed by biphasic sodium titanate and poly(o-methoxyaniline) (Na2Ti3O7/Na2Ti6O13/POMA) with different concentrations of POMA (0%, 1%, 10%, 15%, 35% and 50%) in the ceramic matrix was determined from measurements of complex impedance. The structural details were studied by means of X-ray diffraction, confirming the formation of the Na2Ti3O7/Na2Ti6O13/POMA composites. The displacement of the (200) reflection from 2θ = 10.45° to 11.15° in the composites with 10 and 15% of POMA suggested the partial replacement of H+ for Na+ in the Na2Ti3O7 structure. The thermal properties were investigated by Thermogravimetry and Differential Thermal Analysis. The Thermogravimetry curves of the composites with POMA content of 1, 10 and 15% presented profiles similar to that of pure sodium titanate sample. The composites with 35 and 50% of POMA showed a process at temperatures around 60-70 °C, which was associated with water absorbed by the polymer. The analysis of the complex impedance spectroscopy measurements revealed that the electrical resistivity of the composites in the range from 0 to 35% increased by two orders of magnitude, with different values for each concentration. This positive temperature coefficient of resistivity was less noticeable in the composite with highest POMA mass content (50%). The rapid increase in resistivity caused an increase in the relaxation time calculated from the time domain. The electrical response of the 50% of POMA compound changes in relation to what was observed in the other compounds, which suggests that there is a saturation limit in the increase in resistivity with POMA content.

Comparative genome sequence analysis of several species in the genus Tepidimonas and the description of a novel species Tepidimonas charontis sp. nov.

We performed high-quality genome sequencing of eight strains of the species of the genus Tepidimonas and examined the genomes of closely related strains from the databases to understand why Tepidimonas taiwanensis is the only strain of this genus that utilizes glucose and fructose for growth. We found that the assimilation of these hexoses by T. taiwanensis was due to the presence of two transporters that are absent in all other genomes of strains of members of the genus Tepidimonas examined. Some strains lack genes coding for glucokinase, but the Embden-Meyerhof-Parnas pathway appears to be otherwise complete. The pentose phosphate pathway has a complete set of genes, but genes of the Entner-Doudoroff pathway were not identified in the genomes of any of the strains examined. Genome analysis using average nucleotide identity (ANIb), digital DNA-DNA hybridization (dDDH), average amino acid identity (AAI) and phylogenetic analysis of 400 conserved genes was performed to assess the taxonomic classification of the organisms. Two isolates of the genus Tepidimonas from the hot spring at São Pedro do Sul, Portugal, designated SPSP-6T and SPSPC-18 were also examined in this study. These organisms are mixotrophic, have an optimum growth temperature of about 50 ºC, utilize several organic acids and amino acids for growth but do not grow on sugars. Distinctive phenotypic, 16S rRNA gene sequence and genomic characteristics of strains SPSP-6T and SPSPC-18 lead us to propose a novel species based on strain SPSP-6T for which we recommend the name Tepidimonas charontis sp. nov. (=CECT 9683T=LMG 30884T).

Forecasting the legacy of offshore oil and gas platforms on fish community structure and productivity.

There are currently thousands of offshore platforms in place for oil and gas extraction worldwide, and decommissioning efforts over the next three decades are estimated to cost more than US$200 billion. As platforms reach the end of their useful lifetime, operators and regulatory agencies will assess the environmental impact of potential decommissioning strategies. Among the many factors that will be weighed in preparation for these major economic and engineering challenges is the fate of the fish and invertebrate communities that inhabit the structures underwater. Offshore platforms act as inadvertent artificial reefs, and some are recognized among the most productive fish habitats in the global oceans. We present a model for forecasting changes to fish communities surrounding offshore installations following a series of decommissioning alternatives. Using 24 platforms off southern California, we estimate fish biomass and somatic production under three possible decommissioning scenarios: leave in place, partial removal at 26-m depth, and complete removal of the platform and underlying shell mound. We used fish density and size data from scuba and submersible surveys of the platforms from 1995-2013 to estimate biomass and annual somatic production. Bottom trawl surveys were used to characterize future fish assemblages at platform sites under the complete-removal decommissioning scenario. Based on a conservatively modeled extrapolation of the survey data, we found that complete removal of a platform resulted in 95% or more reduction in the average fish biomass and annual somatic production at the site, while partial removal resulted in far smaller losses, averaging 10% or less. In the event that all surveyed platforms are completely removed, we estimated a total loss of more than 28,000 kg of fish biomass in the Southern California Bight. Platform habitats, which attract reef-dwelling fish species, had minimal overlap in community composition with the surrounding soft-bottom habitat. To best serve the wide range of stakeholder interests, the site-specific biomass, productivity and species composition information provided in this study should be incorporated into strategic decommissioning planning. This approach could be used as a model for informing "rigs to reefs" discussions occurring worldwide.

A new maximum size for the family Nomeidae and the third record of a longfin cigarfish, Cubiceps paradoxus (Stromateoidei: Nomeidae) from California, USA.

We report the largest specimen from the stromateoid family Nomeidae. The specimen, measuring 1283 mm total length unpreserved, was caught on hook and line from shore in Port Hueneme, California, USA in June 2019. Despite scavenging damage, the specimen was identified as a longfin cigarfish, Cubiceps paradoxus, using morphological characters and molecular techniques. This is the third record of C. paradoxus from California. We also provide an account of a previously unreported C. paradoxus collected off the US-Mexico Border in 1999 that was examined but not preserved.

Transfer of Meiothermus chliarophilus (Tenreiro et al.1995) Nobre et al. 1996, Meiothermus roseus Ming et al. 2016, Meiothermus terrae Yu et al. 2014 and Meiothermus timidus Pires et al. 2005, to Calidithermus gen. nov., as Calidithermus chliarophilus comb. nov., Calidithermus roseus comb. nov., Calidithermus terrae comb. nov. and Calidithermus timidus comb. nov., respectively, and emended description of the genus Meiothermus.

Chemotaxonomic parameters, phylogenetic analysis of the 16S rRNA gene, phylogenetic analysis of 90 housekeeping genes and 855 core genes, amino acid identity (AAI), average nucleotide identity (ANI) and genomic characteristics were used to examine the 13 species of the genus Meiothermuswith validly published names to reclassify this genus. The results indicate that the species of the genus Meiothermus can be divided into three lineages on the basis of the results of the phylogenetic analysis, AAI, the guanine+cytosine (G+C) mole ratio, the ability to synthesize the red-pigmented carotenoid canthaxanthin and the colony colour, as well as other genomic characteristics. The results presented in this study circumscribe the genus Meiothermus to the species Meithermus ruber, Meiothermus cateniformans, Meiothermus taiwanensis, Meiothermus cerbereus, Meiothermus hypogaeus, Meiothermus luteus, Meiothermus rufus and Meiothermus granaticius, for which it is necessary to emend the genus Meiothermus. The species Meiothermus silvanus, which clearly represents a separate genus level lineage was not reclassified in this study for lack of any distinctive phenotypic or genotypic characteristics. The results of this study led us to reclassify the species Meiothermus chliarophilus, Meiothermus timidus, Meiothermus roseus and Meiothermus terrae as species of a novel genus for which we propose the epithet Calidithermus gen. nov.

Lysobacter silvestris sp. nov., isolated from alpine forest soil, and reclassification of Luteimonas tolerans as Lysobacter tolerans comb. nov.

A Gram-stain-negative, rod-shaped, motile, catalase-positive and cytochrome c oxidase-positive bacterial strain, designated AM20-91T, was isolated from alpine forest soil. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain AM20-91T was related to the genus Lysobacter and had highest 16S rRNA gene sequence similarities to the type strains of Lysobacter novalis THG-PC7T (97.8 %), Luteimonas tolerans UM1T (97.7 %) and Lysobacter ximonensis XM415T (97.0 %). The strain contained ubiquinone 8 as the predominant respiratory quinone; its polar lipid profile contained phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and two unidentified aminophospholipids. The major cellular fatty acids (>10 %) were iso-C15 : 0, iso-C11 : 0 3-OH and iso-C11 : 0. The DNA G+C content was 63.35 % (draft genome sequence). The combined results of phylogenetic, phenotypic, DNA-DNA relatedness and chemotaxonomic analyses demonstrated that strain AM20-91T represents a novel species of the genus Lysobacter, for which the name Lysobacter silvestris sp. nov. is proposed. The type strain is AM20-91T (=DSM 104734T=LMG 30011). In this study, it is also proposed that Luteimonas tolerans be reclassified as member of the genus Lysobacter.

Proposed minimal standards for the use of genome data for the taxonomy of prokaryotes.

Advancement of DNA sequencing technology allows the routine use of genome sequences in the various fields of microbiology. The information held in genome sequences proved to provide objective and reliable means in the taxonomy of prokaryotes. Here, we describe the minimal standards for the quality of genome sequences and how they can be applied for taxonomic purposes.

Raineya orbicola gen. nov., sp. nov. a slightly thermophilic bacterium of the phylum Bacteroidetes and the description of Raineyaceae fam. nov.

An isolate, designated SPSPC-11T, with an optimum growth temperature of about 50 °C and an optimum pH for growth between 7.5 and 8.0, was recovered from a hot spring in central Portugal. Based on phylogenetic analysis of its 16S rRNA sequence, the new organism is most closely related to the species of the genus Thermonema but with a pairwise sequence similarity of <85 %. The isolate was orange-pigmented, formed non-motile long filaments and rod-shaped cells that stain Gram-negative. The organism was strictly aerobic, oxidase-positive and catalase-positive. The major fatty acids were iso-C15:0, iso-C15 : 0 2-OH and iso-C17 : 0 3-OH. The major polar lipids were one aminophospholipid, two aminolipids and three unidentified lipids. Menaquinone 7 was the major respiratory quinone. The DNA G+C content of strain SPSPC-11T was 37.6 mol% (draft genome sequence). The high quality draft genome sequence corroborated many of the phenotypic characteristics of strain SPSPC-11T. Based on genotypic, phylogenetic, physiological and biochemical characterization we describe a new species of a novel genus represented by strain SPSPC-11T (=CECT 9012T=LMG 29233T) for which we propose the name Raineya orbicola gen. nov., sp. nov. We also describe the family Raineyaceae to accommodate this new genus and species.

Proposal of the suffix -ota to denote phyla. Addendum to 'Proposal to include the rank of phylum in the International Code of Nomenclature of Prokaryotes'.

As an addendum to the earlier proposal to include the rank of phylum in the International Code of Nomenclature of Prokaryotes (Oren et al., Int J Syst Evol Microbiol 2015;65:4284-4287) we propose the suffix -ota to denote phyla, replacing the somewhat awkward -aeota. We therefore present a new draft modified version of Rule 8 of the International Code of Nomenclature of Prokaryotes and a corrected list of names of phyla to be considered for validation after approval of the proposal to include the rank of phylum in the Code.

Solimicrobium silvestre gen. nov., sp. nov., isolated from alpine forest soil.

A Gram-stain-negative, rod-shaped, motile, catalase and cytochrome c oxidase-positive bacterial strain, designated S20-91T, was isolated from alpine forest soil. Growth occurred within a temperature range of 0-25 °C. Yeast extract was required for growth. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain S20-91T was related to the genus Herminiimonas and had the highest 16S rRNA gene sequence similarity to Herminiimonas arsenicoxydans ULPAs1T (96.5 %). The strain contained ubiquinone 8 as the predominant respiratory quinone and phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as the major polar lipids. The major cellular fatty acids (>10 %) were C16 : 1ω7c (55.3 %) and C16 : 0 (25.6 %). The genomic DNA G+C content was 47.6 mol%. Combined data of genomic, phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strain S20-91T represents a novel genus and species, for which the name Solimicrobium silvestre gen. nov., sp. nov. is proposed. The type strain is S20-91T (=DSM 104733T=LMG 30010).

Temporal model for quasi-phase matching in high-order harmonic generation.

We present a model for quasi-phase matching (QPM) in high-order harmonic generation (HHG). Using a one-dimensional description, we analyze the time-dependent, ultrafast wave-vector balance to calculate the on-axis harmonic output versus time, from which we obtain the output pulse energy. Considering, as an example, periodically patterned argon gas, as may be provided with a grid in a cluster jet, we calculate the harmonic output during different time intervals within the drive laser pulse duration. We find that identifying a suitable single spatial period is not straightforward due to the complex and ultrafast plasma dynamics that underlies HHG at increased intensities. The maximum on-axis harmonic pulse energy is obtained when choosing the QPM period to phase match HHG at the leading edge of the drive laser pulse.

Mariniblastus fucicola gen. nov., sp. nov. a novel planctomycete associated with macroalgae.

One strain of a novel genus and species of the order Planctomycetes, designated FC18T, was isolated from the epiphytic community of Fucusspiralis. This strain was non-pigmented in medium M13 but was slightly pink pigmented on medium M14, containing four-fold the levels of glucose, peptone and yeast extract of M13. The organism was primarily spherical, with unicellular non-motile forms and rosettes. The optimal temperature for growth was about 25 °C and the optimal pH was 7.5. FC18T was chemoorganotrophic and aerobic. Several sugars, polyols and amino acids were assimilated. The major fatty acids were C18 : 1ω9c, C14 : 0 and C16 : 0. The major polar lipids were phosphatidylglycerol (PG) and two unknown lipids. Menaquinone 5 (MK-5) was the main respiratory quinone, but MK-6 was also present. The results of the 16S rRNA gene sequence analysis confirmed the affiliation of this organism to the order Planctomycetales, family Planctomycetaceae, with Blastopirellula marina as the closest relative with only 86 % sequence similarity. On the basis of physiological, biochemical and chemotaxonomic characteristics we propose that FC18T(=LMG 29748T=DSM 26290T) represents a novel species of a novel genus of the family Planctomycetaceae for which we propose the name Mariniblastusfucicola gen. nov., sp. nov.

Psychromicrobium silvestre gen. nov., sp. nov., an actinobacterium isolated from alpine forest soils.

Two Gram-stain-variable, non-motile, catalase-positive and cytochrome c oxidase-negative bacteria, designated AK20-18T and AM20-54, were isolated from forest soil samples collected in the Italian Alps. Growth occurred at a temperature range of 5-30 °C, at pH 6-9 and in the presence of 0-5 % (w/v) NaCl. The 16S rRNA gene sequence similarity between strains AK20-18T and AM20-54 was 100 %. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain AK20-18T had highest 16S rRNA gene sequence similarity with the type strain of Arthrobacter psychrochitiniphilus (96.9 %). The cell-wall peptidoglycan structure of strain AK20-18T was of the type A3alpha l-Lys-l-Thr-l-Ala2 (A11.27). The whole-cell sugars were galactose, ribose and lesser amounts of mannose. The major respiratory quinone of the two strains was menaquinone 9(H2) [MK-9(H2)], whereas MK-10(H2) was a minor component. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unknown glycolipids. The major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The genomic DNA G+C content was 59.9 mol%. Combined data of phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strains AK20-18T and AM20-54 represent a novel genus and species, for which the name Psychromicrobium silvestre gen. nov., sp. nov. is proposed. The type strain of Psychromicrobium silvestregen. nov., sp. nov. is AK20-18T (=DSM 102047T=LMG 29369T).

Dehalogenimonas formicexedens sp. nov., a chlorinated alkane-respiring bacterium isolated from contaminated groundwater.

A strictly anaerobic, Gram-stain-negative, non-spore-forming bacterium designated NSZ-14T, isolated from contaminated groundwater in Louisiana (USA), was characterized using a polyphasic approach. Strain NSZ-14T reductively dehalogenated a variety of polychlorinated aliphatic alkanes, producing ethene from 1,2-dichloroethane, propene from 1,2-dichloropropane, a mixture of cis- and trans-1,2-dichloroethene from 1,1,2,2-tetrachloroethane, vinyl chloride from 1,1,2-trichloroethane and allyl chloride (3-chloro-1-propene) from 1,2,3-trichloropropane. Formate or hydrogen could both serve as electron donors. Dechlorination occurred between pH 5.5 and 7.5 and over a temperature range of 20-37 °C. Major cellular fatty acids included C18 : 1ω9c, C14 : 0 and C16 : 0. 16S rRNA gene sequence-based phylogenetic analysis indicated that the strain clusters within the class Dehalococcoidia of the phylum Chloroflexi, most closely related to but distinct from type strains of the species Dehalogenimonas alkenigignens (97.63 % similarity) and Dehalogenimonas lykanthroporepellens (95.05 %). A complete genome sequence determined for strain NSZ-14T revealed a DNA G+C content of 53.96 mol%, which was corroborated by HPLC (54.1±0.2 mol% G+C). Genome-wide comparisons based on average nucleotide identity by orthology and estimated DNA-DNA hybridization values combined with phenotypic and chemotaxonomic traits and phylogenetic analysis indicate that strain NSZ-14T represents a novel species within the genus Dehalogenimonas, for which the name Dehalogenimonas formicexedens sp. nov. is proposed. The type strain is NSZ-14T (=HAMBI 3672T=JCM 19277T=VKM B-3058T). An emended description of Dehalogenimonas alkenigignens is also provided.

Diversity of bacteria and archaea from two shallow marine hydrothermal vents from Vulcano Island.

To obtain new insights into community compositions of hyperthermophilic microorganisms, defined as having optimal growth temperatures of 80 °C and above, sediment and water samples were taken from two shallow marine hydrothermal vents (I and II) with temperatures of 100 °C at Vulcano Island, Italy. A combinatorial approach of denaturant gradient gel electrophoresis (DGGE) and metagenomic sequencing was used for microbial community analyses of the samples. In addition, enrichment cultures, growing anaerobically on selected polysaccharides such as starch and cellulose, were also analyzed by the combinatorial approach. Our results showed a high abundance of hyperthermophilic archaea, especially in sample II, and a comparable diverse archaeal community composition in both samples. In particular, the strains of the hyperthermophilic anaerobic genera Staphylothermus and Thermococcus, and strains of the aerobic hyperthermophilic genus Aeropyrum, were abundant. Regarding the bacterial community, ε-Proteobacteria, especially the genera Sulfurimonas and Sulfurovum, were highly abundant. The microbial diversity of the enrichment cultures changed significantly by showing a high dominance of archaea, particularly the genera Thermococcus and Palaeococcus, depending on the carbon source and the selected temperature.

Spectral control of high-harmonic generation via drive laser pulse shaping in a wide-diameter capillary.

We experimentally investigate spectral control of high-harmonic generation in a wide-diameter (508 µm) capillary that allows using significantly lower gas pressures coupled with elevated drive laser energies to achieve higher harmonic energies. Using phase shaping to change the linear chirp of the drive laser pulses, we observe wavelength tuning of the high-harmonic output to both larger and smaller values. Comparing tuning via the gas pressure with the amount of blue shift in the transmitted drive laser spectrum, we conclude that both adiabatic and non-adiabatic effects cause pulse-shaping induced tuning of high harmonics. We obtain a fractional wavelength tuning, Δλ/λ, in the range from -0.007 to + 0.01, which is comparable to what is achieved with standard capillaries of smaller diameter and higher pressures.

Ampullimonas aquatilis gen. nov., sp. nov. isolated from bottled mineral water.

Two isolates, designated B15.09-116T and B15.09-124, were recovered from bottled mineral water in Portugal. Based on 16S rRNA gene sequence analysis, these strains were related most closely to species of the genus Derxia (belonging to the family Alcaligenaceae) with pairwise sequence similarities of 93.0-93.6 %. The isolates were not pigmented and formed Gram-stain-negative, short, motile rod-shaped cells. The organisms were strictly aerobic, oxidase-positive and catalase-negative. These organisms also fixed N2. The major polar lipids were phosphatidylglycerol and phosphatidylethanolamine. Ubiquinone 8 was the major respiratory quinone. The DNA G+C content of strain B15.09-116T was 49.8 mol%. Based on phylogenetic, physiological and biochemical characteristics the two strains are considered to represent a novel species of a new genus, for which the name Ampullimonas aquatilis gen. nov., sp. nov. is proposed. The type strain of Ampullimonas aquatilis is B15.09-116T ( = CECT 8581T = LMG 28208T).

Nakamurella silvestris sp. nov., an actinobacterium isolated from alpine forest soil.

A Gram-stain-positive, non-motile, catalase-positive and cytochrome c oxidase-negative bacterium, designated strain S20-107T, was isolated from alpine forest soil. Growth occurred at 0-30 °C, at pH 6-9 and in the presence of 0-3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S20-107T was related to the genus Nakamurella and had the highest 16S rRNA gene sequence similarity with Nakamurella flavida DS-52T (96.1 %). Strain S20-107T showed <96.1% 16S rRNA gene sequence similarities to all other recognized members of the genus Nakamurella. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The major whole-cell sugars were glucose, galactose, mannose, arabinose, ribose and rhamnose. The strain contained MK-8(H4) as the predominant menaquinone and diphosphatidylglycerol, phosphatidylethanolamine and an unidentified aminophospholipid as the major polar lipids. The major cellular fatty acids were anteiso-C15 : 0, C16 : 0, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c and/or iso-C15 : 0 2-OH) and iso-C16 : 0. The genomic DNA G+C content was 70.5 mol%. Combined data of phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strain S20-107T represents a novel species of the genus Nakamurella, for which the name Nakamurella silvestris sp. nov. is proposed. The type strain is S20-107T (=DSM 102309T=LMG 29427T).