Spiribacter salilacus sp. nov., a novel moderately halophilic bacterium isolated from a saline lake in China

A Gram-staining-negative, non-motile, rod-shaped or curved rod-shaped, moderately halophilic bacterium, designated C176^T, was isolated from Yuncheng Salt Lake in Shanxi Province, P.R. China. The optimal temperature, salinity and pH for growth of strain C176^T was 37 °C, 6% (w/v) NaCl and 7.5. Phylogenetic analysis using 16S rRNA gene sequences indicated strain C176^T has the highest similarity with Spiribacter salinus LMG 27464 ^T (97.7%), following by the S. halobius E85^T (97.6%), S. curvatus DSM 28542 ^T (97.2%), S. roseus CECT 9117 ^T (97.0%) and S. vilamensis DSM 21056 ^T (96.9%). The ANI and dDDH values between strain C176^T and S. salinus LMG 27464 ^T were 69.8 and 17.7%, respectively. The DNA G + C content of genome for strain C176^T was 54.1%. Summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c) and C_16:0 were detected as its major fatty acids, with content of 38.7 and 28.6% respectively, while Q-8 was the predominant ubiquinone. The major polar lipids of strain C176^T contained phospholipid, phosphatidylglycerol and phosphoglycolipid. In accordance with results of polyphasic taxonomy, strain C176^T is considered as a novel species of the genus Spiribacter, for which the name Spiribacter salilacus sp. nov. is proposed. The type strain is C176^T (= MCCC 1H00417^T = KCTC 72692 ^T).

A Novel Ibuprofen Derivative and Its Complexes: Physicochemical Characterization, DFT Modeling, Docking, In Vitro Anti-Inflammatory Studies, and DNA Interaction

A novel derivative of ibuprofen and salicylaldehyde N′-(4-hydroxybenzylidene)-2-(4-isobutylphenyl) propane hydrazide (HL) was synthesized, followed by its complexation with Cu, Ni, Co, Gd, and Sm. The compounds obtained were characterized by ¹HNMR, mass spectrometry, UV-Vis spectroscopy, FT-IR spectroscopy, thermal analysis (DTA and TGA), conductivity measurements, and magnetic susceptibility measurements. The results indicate that the complexes formed were [Cu(L)(H₂O)]Cl·2H₂O, [Ni(L)₂], [Co(L)₂]·H₂O, [Gd(L)₂(H₂O)₂](NO₃)·2H₂O and [Sm(L)₂(H₂O)₂](NO₃)·2H₂O. The surface characteristics of the produced compounds were evaluated by DFT calculations using the MOE environment. The docking was performed against the COX2 targeting protein (PDB code: 5IKT Homo sapiens). The binding energies were −7.52, −9.41, −9.51, −8.09, −10.04, and −8.05 kcal/mol for HL and the Co, Ni, Cu, Sm, and Gd complexes, respectively, which suggests the enhancement of anti-inflammatory behaviors compared with the binding energy of ibuprofen (−5.38 kcal/mol). The anti-inflammatory properties of the new compounds were assessed in vitro using the western blot analysis method and the enzyme-linked immunosorbent assay (ELISA), consistent with the outcomes obtained from docking. The half-maximal inhibitory concentration (IC₅₀) values are 4.9, 1.7, 3.7, 5.6, 2.9, and 2.3 µM for HL and the Co, Ni, Cu, Sm, and Gd complexes, respectively, showing that they are more effective inhibitors of COX2 than ibuprofen (IC₅₀ = 31.4 µM). The brain or intestinal estimated permeation method (BOILED-Egg) showed that HL and its Co complex have high gastrointestinal absorption, while only the free ligand has high brain penetration. The binding constants of Co, Cu, and Gd complexes with DNA were recorded as 2.20 × 10⁴, 2.27 × 10^6, and 4.46 × 10³ M⁻¹, respectively, indicating the intercalator behavior of interaction. The newly synthesized ibuprofen derivative and its metal complexes showed greater anti-inflammatory activity than ibuprofen.