Alcanivorax quisquiliarum sp. nov., isolated from anaerobic fermentation liquid of food waste by high-throughput cultivation.

Strain CY1518T was isolated from an anaerobic fermentation liquid of food waste treatment plant in Beijing, PR China, and characterized to assess its taxonomy. Cells of CY1518T were Gram-stain-negative, oxidase-negative, catalase-positive and ellipsoidal. Growth occurred at 20-42 °C (optimum, 37 °C), pH 6.0-10.0 (optimum, pH 8) and with 0-6.0 % (w/v) NaCl (optimum, 1.5%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CY1518T belongs to the genus Alcanivorax, with the highest sequence similarity to Alcanivorax pacificus W11-5T (95.97 %), followed by Alcanivorax indicus SW127T (95.08%). The similarity between strain CY1518T and other strains of Alcanivorax was less than 95 %. The genomic DNA G+C content of strain CY1518T was 60.88 mol%. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between strain CY1518T and the closely related taxa A. pacificus W11-5T and A. indicus SW127T were 77.61, 78.03 and 21.2 % and 74.15, 70.02 and 19.3%, respectively. The strain was able to use d-serine, Tween 40 and some organic acid compounds for growth. The polar lipids comprised aminophospholipid, diphosphatidylglycerol, glycolipid, an unknown polar lipid, phosphatidylethanolamine, phosphatidylglycerol and phospholipid. The principal fatty acids (>5 %) were C19 : 0 cyclo ω8c (36.3%), C16 : 0 (32.3%), C12 : 0 3-OH (8.3%) and C12 : 0 (7.6%). Based on its phenotypic, genotypic and genomic characteristics, strain CY1518T represents a novel species in the genus Alcanivorax, for which the name Alcanivorax quisquiliarum sp. nov. is proposed. The type strain is CY1518T (=GDMCC 1.2918T=JCM 35120T).

Development of an efficient method for separation and purification of cordycepin from liquid fermentation of Cordyceps militaris and analysis of cordycepin antitumor activity.

Cordycepin (3 '-deoxyadenosine) is the main active component of Cordyceps militaris, which is a chemical marker for quality detection of Cordyceps militaris and has important medicinal development value. Existing methods for obtaining cordycepin are complex and costly. In this study, an economical and simple method for separation and purification of cordycepin from Cordyceps militaris fermentation liquid through physical crystallization was explored. First, lyophilized powdered fermentation liquid (LPFL) and pure methanol (1 g/100 mL, w/v) were mixed, and then repeatedly dissolved and crystallized until the precipitation was white. Purified product was obtained by freeze-drying the precipitate. The substance was determined to be cordycepin by high performance liquid chromatography, mass spectrometry and infrared spectroscopy, and the purity was 94.26%. Compared with the existing methods, this method is simple and low cost. In addition, the functional activity of cordycepin was determined by in vitro test. The results exhibited that cordycepin caused death and morphological changes in human colon cancer Caco-2 cells, and significantly inhibited the proliferation of Caco-2 cells, with a half-maximal inhibitory concentration (IC50) of 107.2 µg/mL. Cordycepin could induce early apoptosis of Caco-2 and caused cell cycle arrest in the G2 phase. Caco-2 cell apoptosis and cell cycle arrest showed dose dependence to cordycepin over a certain range. These results improved cordycepin purification method, provided insights into the mechanism of cordycepin in cancer inhibition, and would provide important reference for further development and clinical application of cordycepin.

Roseococcus pinisoli sp. nov., lacking pufL and pufM bacteriochlorophyll a: synthesizing genes.

A Gram-stain-negative, cocci-to-oval-shaped bacterial strain, designated XZZS9T, was isolated from the rhizosphere soil of Pinus sylvestris var. mongolica and characterized taxonomically using a polyphasic approach. Growth occurred at 20-35 °C (optimum, 28 °C), pH 6.0-11.0 (optimum, pH 7.0), and in 0-1% NaCl (optimum, 0%). Phylogenetic analysis based on 16S rRNA gene sequencing indicated that strain XZZS9T was related to members of the genus Roseococcus, with the highest sequence identity to Roseococcus microcysteis NIBR12T (96.9%). The major cellular fatty acids (> 5% of the total) were C18:1 ω7c and C19:0 cyclo ω8c. The major isoprenoid quinone was Q-9 and the polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified glycophospholipid, and an unidentified phospholipid. Genome sequencing revealed that had a genome size of 4.79 Mbp with a G + C content of 69.5%. Comparative genomic analyses clearly separated strain XZZS9T from the known species of the genus Roseococcus based on average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values below the thresholds for species delineation. Genome annotations did not find pufL and pufM genes in strain XZZS9T, suggesting a possible lack of photosynthetic reaction. Based on genotypic and phenotypic characteristics, strain XZZS9T represents a novel species of the genus Roseococcus, for which we propose the name Roseococcus pinisoli sp. nov. The type strain is XZZS9T (= KCTC 82435T = JCM 34402T = GDMCC 1.2158T).