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Abstract Rising atmospheric carbon dioxide (CO 2), primarily from anthropogenic emissions, are resulting in increasing absorption of CO 2 by the oceans, leading to a decline in oceanic pH in a process known as ocean acidification (OA). There is a growing body of evidence demonstrating the potential effect of OA on the energetics/physiology and consequently life-history traits of commensally important marine organisms. However, despite this little is known of how fundamental metabolic pathways that underpin changes in organismal physiology are affected by OA. Consequently, a gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) based metabolic profiling approach was applied to examine the metabolic responses of Crassostrea gigas to elevated p CO 2 levels, under otherwise natural field conditions. Oysters were exposed natural environmental p CO 2 (~625.40 μatm) and elevated p CO 2 (~1432.94 μatm) levels for 30 days. Results indicated that 36 differential metabolites were identified. Differential metabolites were mapped in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database to search for the related metabolic pathways. Pathway enrichment analysis indicates that alanine, aspartate and glutamate metabolism and glycine, serine and threonine metabolism were the most statistically enriched pathways. Further analysis suggested that elevated p CO 2 disturb the TCA cycle via succinate accumulation and C. gigas most likely adjust their energy metabolic via alanine and GABA accumulation accordingly to cope with elevated p CO 2. These findings provide an understanding of the molecular mechanisms involved in modulating C. gigas metabolism under elevated p CO 2. [ABSTRACT FROM AUTHOR]

Lichtheimia ramosais one of the predominant filamentous fungi in Korean traditionalnuruk. The nonvolatile and volatile metabolites ofL. ramosacultivated in three growth media: complete medium (CM), potato dextrose broth (PDB), and sabouraud dextrose broth (SDB), were investigated and compared. Among nonvolatile metabolites, serine, lysine, and ornithine increased in CM and PDB cultivated withL. ramosaduring the exponential phase. In addition, glucose level increased in CM whereas decreased in PDB and SDB. The major volatile metabolites in the extract samples were acetic acid, ethanol, 3-methyl-2-buten-1-ol, 2-phenylethanol, ethylacetate, 2-furaldehyde, 5-(hydroxymethyl)-2-furaldehyde, 2,3-dihydro-3,5,-dihydroxy-6-methyl-4H-pyran-4-one, andα-humulene. In particular, the levels of volatile metabolites related tomakgeolli(e.g., acetic acid, ethanol, and ethyl acetate) were highest in extracts cultivated in CM. On the other hand, the level of 2-phenylethanol was relatively higher in PDB and SDB, possibly due to there being more phenylalanine present in the biomass sample in media. [ABSTRACT FROM PUBLISHER]

The microplastic particles with 29 pyrolyzate compounds of marine water samples from the seashore locations in Cape Town, South Africa were analysed using Pyrolysis- GC-TOF-MS. The mass spectra data documented the presence of various chemical groups that include alkanes, alkenes, dienes, fatty acids and esters, biphenyl and benzene (along with derivatives). Out of 16 identified polymers in the study area, polythene (PE) was the dominant in six out of seven locations with 87.5% followed by polyethylene terephthalate (PET) and polyvinylchloride (PVC) in five (71.4%) and four (57.1%) out of seven locations respectively. The other constituent polymers of microplastics identified through pyrolyzates were polystyrene (PS), polyamide 12 (PA-12) polyacrylic acid (PAA) and ethyl vinyl acetate (EVA) copolymer. The microplastic samples contained six additives predominantly in the family of fatty acid esters and nine plasticizers from alcohols, carboxylic esters and acids. The base peaks of m/z 41, 43, 55, 57, 69, 73, 91, 102, 105, 127 and 154 were characterized respectively with the fragmented species of C 3 H 5 +, C 3 H 7 +, C 4 H 7 +, C 4 H 9 +, C 5 H 9 +, C 3 H 5 O 2 +, C 7 H 7 +, C 3 H 10 O 2 +(McLafferty ion), C 8 H 9 +, C 8 H 15 O+ and C 12 H 10 +. Accordingly to Globally Harmonized System (GHS) of hazard classification, about 27.4% of pyrolyzates are Irritants, 31.4% of pyrolyzates found to be Irritants along with other hazards such as Flammable, Compressed Gas, Environmental Hazard, Corrosive, Health Hazard, Acute Toxicity and Allergy. About 41.2% of the pyrolyzates are not classified under the Irritant category. Characterizations of the plastic microparticles from the seven seashore locations such as FTIR, SEM with EDX and TGA were also done and discussed to understand the functional groups, surface morphology with elemental composition and stability respectively of the polymeric microparticles. Image 1 • Py – GC – TOF – MS revealed the presence of 16 polymer types in microplastic samples. • The mass spectra recognized 29 pyrolyzates in the microplastics of marine samples. • Pyrolyzates of 37% are Specific Target Organ Toxicants and 27.4% are irritants. Analysis of microplastics in the Atlantic Ocean seashore samples based on Pyrolyzate product identification and Characterization of plastic micro particles. [ABSTRACT FROM AUTHOR]