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► Pseudomonas chlororaphis was investigated for production of mcl-PHA latex under controlled conditions on bioreactor scale ► A surplus material, namely saturated biodiesel fraction ...from animal waste lipids, was used as the sole carbon source ► A detailed kinetic analysis of the bioprocess is provided ► Productivity of the mcl-PHA latex is competitive to other mcl-PHA producing organisms on expensive carbon sources.
A novel description of mcl-PHA biosynthesis by Ps. chlororaphis from tallow-based biodiesel as an inexpensive carbon feed stock is presented. Fermentation protocols, kinetic analysis, an efficient product recovery strategy, and product characterization are included. Maximum specific growth rates (μmax.) of 0.08 h−1, 0.10 h−1 and 0.13 h−1, respectively, were achieved in three different fermentation set-ups. Volumetric productivity for mcl-PHA amounted to 0.071g/L h, 0.094g/L h and 0.138g/L h, final intracellular PHA contents calculated from the sum of active biomass and PHA from 22.1 to 29.4wt.-%, respectively. GC-FID analysis showed that the obtained biopolyester predominantly consists of 3-hydroxyoctanoate and 3-hydroxydecanoate, and, to a minor extent, 3-hydroxydodecanoate, 3-hydroxynonanoate, 3-hydroxyhexanoate, and 3-hydroxyheptanoate monomers. The overall distribution of the monomers remained similar, regardless to working volumes, biodiesel concentrations and pre-treatment of the inoculum.
This study describes a method for the detection and characterization of mycosporines-like compounds including mycosporine and MAAs in lichens, using HPLC-DAD–MSn, UPLC–HRMS and HPTLC–UV. Display ...omitted
► An optimized technique for the purification of mycosporines and MAAs in lichens. ► Detection and identification of mycosporines using HPTLC and -HPLC-DAD–MS. ► Lichens appear to be a great reservoir of mycosporines. ► Mycosporines and MAAs are investigated in cyanolichens series. ► Mycosporine hydroxyglutamicol is here described for the first time.
Mycosporine-like compounds, comprising mycosporines and mycosporine-like amino acids (MAAs) are UV protecting secondary metabolites described in organisms such as fungi, algae, cyanobacteria or animals. Lichens however, were only poorly investigated for such constituents so far. Here, a method for the characterization of mycosporines and MAAs in purified aqueous extracts, involving HPTLC coupled to spectrophotodensitometry, HPLC-DAD–MSn and UPLC–HRMS analysis, is described. This optimized protocol was validated on three algae and one cyanolichen containing known MAAs and mycosporines, and then applied to 18 cyanolichen species. Analyses revealed the presence of five already described mycosporine-like compounds in the investigated species, including mycosporine serinol in Lichina and Peltigera species and mycosporine glutamicol in Degelia plumbea. Apart from that, eight unknown mycosporine-like compounds were detected and tentatively characterized on the basis of their DAD spectra and their MSn and HRMS data: two in the alga Porphyra dioica and six in cyanolichen species belonging to the genera Degelia, Nephroma and Stereocaulon. From Nephroma laevigatum, the mycosporine hydroxyglutamicol was preparatively isolated and identified through HRMS, 1D and 2D NMR spectroscopic data. The optimized analytical protocol allowed the characterization of mycosporine-like compounds in small amounts of material and confirmed the potential of cyanolichens as a source of mycosporine compounds. It should also be applicable to investigate lichen species with green algae photobionts for mycosporine-like compounds.
A bioassay‐guided phytochemical analysis of the ethanolic extract of Grindelia argentina Deble & Oliveira‐Deble (Asteraceae) allowed the isolation of a known flavone, hispidulin, and three new ...oleanane‐type saponins, 3‐O‐β‐D‐xylopyranosyl‐(1→3)‐β‐D‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D‐xylopyranosyl‐(1→2)‐β‐D‐apiofuranosyl‐(1→3)‐β‐D‐xylopyranosyl‐(1→3)‐α‐L‐rhamnopyranosyl‐(1→2)‐α‐L‐arabinopyranosyl ester (2), 3‐O‐β‐D‐glucopyranosyl‐2β,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D‐xylopyranosyl‐(1→2)‐β‐D‐apiofuranosyl‐(1→3)‐β‐D‐xylopyranosyl‐(1→3)‐α‐L‐rhamnopyranosyl‐(1→2)‐α‐L‐arabinopyranosyl ester, (3) and 3‐O‐β‐D‐xylopyranosyl‐(1→3)‐β‐D‐glucopyranosyl‐2β,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D‐xylopyranosyl‐(1→2)‐β‐D‐apiofuranosyl‐(1→3)‐β‐D‐xylopyranosyl‐(1→3)‐α‐L‐rhamnopyranosyl‐(1→2)‐α‐L‐arabinopyranosyl ester (4), named grindeliosides A–C, respectively. Their structures were determined by extensive 1D‐ and 2D‐NMR experiments along with mass spectrometry and chemical evidence. The isolated compounds were evaluated for their inhibitory activities against LPS/IFN‐γ‐induced NO production in RAW 264.7 macrophages and for their cytotoxic activities against the human leukemic cell line CCRF‐CEM and MRC‐5 lung fibroblasts. Hispidulin markedly reduced LPS/IFN‐γ‐induced NO production (IC50 51.4 μM), while grindeliosides A–C were found to be cytotoxic, with grindelioside C being the most active against both CCRF‐CEM (IC50 4.2±0.1 μM) and MRC‐5 (IC50 4.5±0.1 μM) cell lines.
mcl-PHA biosynthesis by Pseudomonas citronellolis from tallow-based biodiesel as inexpensive carbon feed stock was accomplished. Fermentation protocols, kinetic analysis, an efficient product ...recovery strategy, and a detailed product characterization are presented.
A maximum specific growth rate, μmax. of 0.10 and 0.08h−1, respectively, was achieved in two different fermentation set-ups. Volumetric productivity for mcl-PHA amounted to 0.036g/Lh and 0.050g/Lh, final intracellular PHA contents calculated from the sum of active biomass and PHA to 20.1 and 26.6wt.%, respectively. GC-FID analysis showed that the obtained biopolyester predominantly consists of 3-hydroxyoctanoate and 3-hydroxydecanoate, and, to a minor extent, 3-hydroxydodecanoate, 3-hydroxynonanoate, 3-hydroxyhexanoate, and 3-hydroxyheptanoate monomers. This was confirmed by 1H- and 13C NMR, also evidencing the occurrence of low quantities of unsaturated and 3-hydroxyvalerate building blocks. High purity of the recovered materials was proofed by elemental analysis. Regarding the results from thermogravimetric analysis, differential scanning calorimetry and molecular mass determination, results were in a range typical for this type of PHA (1st fermentation: decomposition temperature Td=296°C, peak of melting range Tm=48.6°C; glass transition temperature Tg=−46.9°C, degree of crystallinity Xc=12.3%, Mw=66,000, Mn=35,000, dispersity index Pi=1.9; 2nd fermentation: Td=295°C, Tm=53.6°C, Tg=-43.5°C, Xc=10.4%, Mw=78,000, Mn=196,000, Pi=2.5).
