Major Fatty Acids Research Articles

Pengzhenrongella frigida sp. nov., isolated from a glacier.

A Gram-stain-positive, rod-shaped bacterium, designated as HLT2-17T, was isolated from soil sample taken from the Hailuogou glacier in Sichuan province, PR China. Strain HLT2-17T was capable of growing at 4-25°C and in NaCl concentrations ranging from 0 to 2% (w/v). The highest level of 16S rRNA gene sequence similarity was observed with Pengzhenrongella phosphoraccumulans M0-14T (98.3 %) and Pengzhenrongella sicca LRZ-2T (98.2 %). The average nucleotide identity and digital DNA-DNA hybridization values between strain HLT2-17T and its closest relatives, P. phosphoraccumulans M0-14T and P. sicca LRZ-2T, were 80.0-84.0 % and 23.3-27.7 %, respectively. Phylogenomic analysis indicated that strain HLT2-17T clustered together with strains P. phosphoraccumulans M0-14T and P. sicca LRZ-2T. Strain HLT2-17T contained C16 : 0 and anteiso-C15 : 0 as the major fatty acids, and MK-9(H4) as the menaquinone. Therefore, based on a polyphasic approach, we propose that strain HLT2-17T (=CGMCC 1.11116T= NBRC 110443T) represents a novel species of the genus Pengzhenrongella and suggest the name Pengzhenrongella frigida sp. nov.

Nocardioides agri sp. nov., isolated from garden soil.

A novel bacterial strain, designated as MAH-18T, was isolated from soil sampled in a flower garden. Cells of strain MAH-18T were Gram-stain-positive, aerobic, motile, and rod-shaped. The colonies were beige in colour, smooth, and spherical when grown on Reasoner's 2A agar medium. Strain MAH-18T grew at 20-40 °C, pH 6.0-8.0, and 0-1.0 % NaCl. Cells were able to hydrolyse aesculin, gelatin, and Tween 20. According to the 16S rRNA gene sequence comparisons, the isolate was determined to be a member of the genus Nocardioides and most closely related to Nocardioides pyridinolyticus OS4T (97.9 %), Nocardioides hankookensis DS-30T (97.9 %), Nocardioides aquiterrae GW-9T (97.6 %), Nocardioides soli mbc-2T (97.5 %), Nocardioides conyzicola HWE 2-02T (97.4 %), and Nocardioides mangrovi GBK3QG-3T (96.3 %). Strain MAH-18T has a draft genome size of 4 788 325 bp (eight contigs), 4572 protein-coding genes, 46 tRNA, and three rRNA genes. The average nucleotide identity and digital DNA-DNA hybridization values between strain MAH-18T and the closest type strains were 81.5-83.4 % and 24.4-25.8 %, respectively. In silico genome mining revealed several biosynthetic gene clusters in the genome of the novel strain MAH-18T. The G+C content of the genomic DNA of strain was 72.2 mol% and the predominant isoprenoid quinone was MK-8 (H4). The main polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, and unknown phospholipids. The major cellular fatty acids were determined to be C16:0 iso and C17 : 1 ω6c. The DNA-DNA hybridization results and phenotypic, genotypic, and chemotaxonomic data demonstrated that strain MAH-18T represents a novel species, for which the name Nocardioides agri sp. nov. is proposed, with MAH-18T as the type strain (=KACC 19744T=CGMCC 1.13656T).

Paenibacillus gyeongsangnamensis sp. nov., Isolated from Soil.

A Gram-stain-positive, aerobic, white-coloured, rod-shaped bacteria, designated as a strain dW9T, was isolated from soil. Strain dW9T was catalase-positive and oxidase-negative. Strain dW9T grew at temperature of 20-37°C and at pH of 5.0-7.0. Phylogenetic and 16S rRNA gene analysis indicated that strain dW9T belonged to the genus Paenibacillus with its closest relative being Paenibacillus filicis S4T (97.4% sequence similarity). The genome size of dW9T was 7,787,916 bp with DNA G+C content of 51.3%. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values of dW9T with its closest relatives were found to be <22.0% and <74.0%, respectively. The only respiratory quinone was MK-7, and the major fatty acids were antiso-C15:0 and iso-C16:0. Overall, the comprehensive taxonomic analysis revealed that strain dW9T met all the fundamental criteria to be classified as a novel species within the genus Paenibacillus. Accordingly, we propose the name Paenibacillus gyeongsangnamensis sp. nov., with the type strain dW9T (=KCTC 43431T =NBRC 116022T).

In vitro digestion and culture in Caco‐2 cells to assess the bioavailability of fatty acids: A case study in meat matrix enriched with ω‐3 microcapsules

AbstractThis work aimed to evaluate the Caco‐2 cells as a model to study the epithelial transport of intestinal lipid extracts subjected to in vitro digestion, to establish a standard protocol for the determination of bioaccessibility and bioavailability of fatty acids in meat matrix, especially in those enriched with ω‐3 (eicosapentaenoic (EPA) and docosahexaenoic acids (DHA)). Samples were first subjected to in vitro digestion, and then, the intestinal extract was incubated with Caco‐2 cells. A first trial was conducted to select the most influencing variables on the fatty acid transport during Caco‐2 cell incubation: fat quantity on the intestinal extract, incubation time, and shaking. Then, a second experiment was carried out to determine the influence of these variables, being the fat quantity and the incubation time the most influencing factors on the transport and bioavailability of fatty acids. The effect of shaking was not so marked but seemed to improve the bioavailability of saturated fatty acids. This study also allows establishing the most suitable conditions: intestinal extracts with 30 mg of fat, longer incubation times (8 h), and shaking, achieving active and passive fatty acid transport without compromising the integrity of the Caco‐2 cell monolayer. The accurate results obtained for major and minor fatty acids, especially EPA and DHA are remarkable, due to the interest in these bioactive compounds. Thus, this study provides a combined protocol based on static in vitro digestion followed by Caco‐2 cell incubation to assess the bioaccessibility and bioavailability of fatty acids in meat samples.

Niabella defluvii sp. nov., isolated from influent water of a wastewater treatment plant.

Strain I65T (=KACC 22647T=JCM 35315T), a novel Gram-stain-negative, strictly aerobic, non-motile, non-spore-forming, rod-shaped, and orange-pigmented bacterium was isolated from influent water of a wastewater treatment system after treatment with several antibiotics, such as meropenem, gentamicin, and macrolide. The newly identified bacterial strain I65T exhibits significant multi-drug and heavy metal resistance characteristics. Strain I65T was grown in Reasoner's 2A medium [0 %-2 % (w/v) NaCl (optimum, 0 %), pH 5.0-10.0 (optimum, pH 7.0), and 20-45°C (optimum, 30 °C)]. Phylogenetic analysis based on 16S rRNA gene sequencing confirmed that strain I65T was closely related to Niabella yanshanensis CCBAU 05354T (99.56 % sequence similarity), Niabella hibiscisoli THG-DN5.5T (97.51 %), and Niabella ginsengisoli GR10-1T (97.09 %). Further analysis of the whole-genome sequence confirmed that the digital DNA-DNA hybridization, average nucleotide identity, and average amino acid identity values between strain I65T and N. yanshanensis CCBAU 05354T were 23.4, 80.7, and 85.0 %, respectively, suggesting that strain I65T is distinct from N. yanshanensis. The genome size of strain I65T was 6.1 Mbp, as assessed using the Oxford Nanopore platform, and its genomic DNA G+C content was 43.0 mol%. The major fatty acids of strain I65T were iso-C15 : 0 and iso-C15 : 1 G, and the major respiratory quinone was MK-7. Moreover, the major polar lipid of strain I65T was phosphatidylethanolamine. Based on genotypic, chemotaxonomic, and phenotype data, strain I65T represents a novel species belonging to the genus Niabella, for which the name Niabella defluvii sp. nov. is proposed. The type strain is I65T (=KACC 22647T=JCM 35315T).

Gemmobacter denitrificans sp. nov., a denitrifying bacterium, isolated from pond water for Litopenaeus vannamei.

A novel Gram-stain-negative strain, designated JM10B15T, was isolated from pond water for Litopenaeus vannamei collected from Jiangmen City, Guangdong province, south PR China. Cells of the strain were aerobic, rod-shaped, and motile by lateral flagella. JM10B15T could grow at 15-40 °C, pH 6.0-9.5, and in 0-3.0 % NaCl, with optimal growth at 25-35 °C, pH 7.5-8.5, and in 0 % NaCl, respectively. Furthermore, this strain grew well on Reasoner's 2A agar but not on nutrient broth agar or Luria-Bertani agar. JM10B15T was a denitrifying bacterium capable of removing nitrites and nitrates, and three key functional genes, nasA, nirS, and nosZ, were identified in its genome. The results of phylogenetic analyses based on the 16S rRNA gene and genome sequences indicated that JM10B15T belonged to the genus Gemmobacter. JM10B15T showed the highest 16S rRNA sequence similarity to Gemmobacter lutimaris YJ-T1-11T (98.8 %), followed by Gemmobacter aquatilis IFAM 1031T (98.6 %) and Gemmobacter serpentinus HB-1T (98.1 %). The average nucleotide identity and digital DNA-DNA hybridization values between JM10B15T and the other type strains of genus Gemmobacter were 78.1-82.1 % and 18.4-22.1 %, respectively. The major fatty acids of strain JM10B15T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) and C18 : 1 ω7c 11-methyl. In addition, the major respiratory quinone of this novel strain was Q-10, and the predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, four unidentified phospholipids, three unidentified lipids, and an unidentified aminophospholipid. Results of analyses of the phylogenetic, genomic, physiological, and biochemical characteristics indicated that JM10B15T represents a novel species of the genus Gemmobacter, for which the name Gemmobacter denitrificans sp. nov. is proposed. The type strain is JM10B15T (=GDMCC 1.4148T=KCTC 8140T).

Tessaracoccus lacteus sp. nov., Isolated from the Sludge of a Wastewater Treatment Plant.

A bacterium, designated strain T21T, that is non-motile, rod-shaped, and formed pale white colonies, was isolated from the sludge of a wastewater treatment plant's secondary sedimentation tank in China. Strain T21T could grow at 20-40°C (optimum growth at 30°C), pH 3.0-10.0 (optimum growth at pH 5.0) and in the presence of 0-8.0% (w/v) NaCl (optimum growth at 2.0%). Based on phylogenetic analysis of 16S rRNA gene sequences and genome sequences, the isolate belongs to the genus Tessaracoccus in the phylum Actinomycetota. It exhibited a close relationship with Tessaracoccus palaemonis J1M15T, Tessaracoccus defluvii LNB-140T, Tessaracoccus flavescens SST-39T, and Tessaracoccus coleopterorum HDW20T. The 16S rRNA gene sequence similarities are 99.8%, 97.9%, 97.9%, and 97.8%, respectively. The major cellular fatty acids were anteiso-C15:0 and C16:0. The main respiratory quinone was MK-9(H4). The polar lipids included phosphatidylglycerol, diphosphatidylglycerol, glycolipid, and phospholipid. Genome annotation of strain T21T predicted the presence of 2829 genes, of which 2754 are coding proteins and 59 are RNA genes. The genomic DNA G+C content was 69.2%. Based on the results of phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses, we propose the name Tessaracoccus lacteus sp. nov. for this novel species within the genus Tessaracoccus. The type strain is T21T (=CCTCC AB 2023031T = KCTC 49936T).

Flavobacterium poyangense sp. nov., an ammonifying bacterium isolated from a freshwater lake.

A Gram-stain-negative, aerobic, non-spore-forming, nonmotile, rod-shaped, and yellow-pigmented bacterium, designated strain JXAS1T, was isolated from a freshwater sample collected from Poyang Lake in China. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the isolate belonged to the genus Flavobacterium, being closest to Flavobacterium pectinovorum DSM 6368T (98.61 %). The genome size of strain JXAS1T was 4.66 Mb with DNA G+C content 35.7 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain JXAS1T and its closest relatives were below the threshold values of 95 and 70 %, respectively. The strain contained menaquinone 6 (MK-6) as the predominant menaquinone and the major polar lipids were phosphatidylethanolamine, one unidentified glycolipid, and one unidentified polar lipid. The major fatty acids (>5 %) were iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C15 : 0, iso-C17 : 0 3OH, iso-C15 : 0 3OH, and summed feature 9 (iso-C17 : 1 ω9c and/or 10-methyl C16 : 0). Based on phylogenetic, genotypic, and phenotypic evidence, the isolated strain represents a new species in the genus Flavobacterium, and the name Flavobacterium poyangense is proposed. The type strain is JXAS1T (=GDMCC 1.1378T=KCTC 62719T).

Clostridium aquiflavi sp. nov., isolated from yellow water of Nongxiangxing baijiu in the Yibin region of China.

A Gram-stain-positive, strictly anaerobic, endospore-forming and rod-shaped (0.6-0.8×2.7-13.1 µm) bacterium, designated as 5 N-1T, was isolated from a yellow water sample collected from the manufacturing process of Nongxiangxing baijiu in the Yibin region of Sichuan, PR China. Growth occurred at 15-40 °C (optimum growth at 37 °C), at pH 6.0-9.0 (optimum growth at pH 7.0) and in NaCl concentrations of 0-1 % (w/v) and ethanol concentrations of 0-2 % (v/v). The major fatty acids in strain 5 N-1T were C16 : 0, C18 : 0 and C14 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified aminophospholipids and one unidentified lipid. Phylogenetic analysis of its 16S rRNA gene sequence indicated that strain 5 N-1T was most closely related to Clostridium weizhouense YB-6T (97.70 %) and Clostridium uliginosum DSM 12992T (97.56 %). The average nucleotide identity and digital DNA‒DNA hybridization values between strain 5 N-1T and the above two type strains were 80.89 and 80.05 % and 25.80 and 25.30 %, respectively, which were all below the species thresholds. The genome size of strain 5 N-1T was 3.5 Mbp and the DNA G+C content was 27.5 mol%. Based on the results of phenotypic and genotypic analyses, strain 5 N-1T represents a novel species of the genus Clostridium, for which the name Clostridium aquiflavi sp. nov. is proposed. The type strain is Clostridium aquiflavi 5 N-1T (=CICC 24886T=JCM 35355T).

Clostridium omnivorum sp. nov., isolated from anoxic soil under the treatment of reductive soil disinfestation.

Reductive soil disinfestation (RSD), also known as biological soil disinfestation, is a bioremediation method used to suppress soil-borne plant pathogens by stimulating the activity of indigenous anaerobic bacteria in the soil. An anaerobic bacterial strain (E14T) was isolated from an anoxic soil sample subjected to RSD treatment and then comprehensively characterized. Cells of the strain were Gram-stain-positive, curved to sigmoid, and spore-forming rods. Cells were motile with a polar flagellum. Strain E14T grew in peptone-yeast extract broth, indicating that it utilized proteinous compounds. Strain E14T was also saccharolytic and produced acetate, isobutyrate, butyrate, isovalerate and gases (H2 and CO2) as fermentation products. The strain did not decompose any of examined polysaccharides except for starch. The major cellular fatty acids of strain E14T were iso-C15:0 and iso-C15:0 DMA. The closest relative to strain E14T, based on 16S rRNA gene sequences, was Clostridium thermarum SYSU GA15002T (96.2 %) in the Clostridiaceae. Whole-genome analysis of strain E14T showed that its genome was 4.66 Mb long with a genomic DNA G+C content of 32.5 mol%. The average nucleotide identity (ANIb) between strain E14T and C. thermarum SYSU GA15002T was 69.0 %. The presence of the genes encoding glycolysis and butyrate production via the acetyl-CoA pathway was confirmed through genome analysis. Based on the obtained phylogenetic, genomic and phenotypic data, we propose that strain E14T should be assigned to the genus Clostridium in the family Clostridiaceae as Clostridium omnivorum sp. nov. The type strain is E14T (=NBRC 115133T=DSM 114974T).

Roseobacter fucihabitans sp. nov., isolated from the brown alga Fucus spiralis.

A Gram-negative, aerobic, pink-pigmented, and bacteriochlorophyll a-containing bacterial strain, designated B14T, was isolated from the macroalga Fucus spiralis sampled from the southern North Sea, Germany. Based on 16S rRNA gene sequences, species of the genera Roseobacter and Sulfitobacter were most closely related to strain B14T with sequence identities ranging from 98.15 % (Roseobacter denitrificans Och 114T) to 99.11 % (Roseobacter litoralis Och 149T), whereas Sulfitobacter mediterraneus CH-B427T exhibited 98.52 % sequence identity. Digital DNA-DNA hybridization and average nucleotide identity values between the genome of the novel strain and that of closely related Roseobacter and Sulfitobacter type strains were <20 % and <77 %, respectively. The novel strain contained ubiquinone-10 as the only respiratory quinone and C18 : 1 ω7c, C16 : 0, C18 : 0, C12 : 1 ω7c, C18 : 2 ω7,13c, and C10 : 0 3-OH as the major cellular fatty acids. The predominant polar lipids of strain B14T were phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The genome of strain B14T comprises a chromosome with a size of 4.5 Mbp, one chromid, and four plasmids. The genome contains the complete gene cluster for aerobic anoxygenic photosynthesis required for a photoheterotrophic lifestyle. The results of this study indicate that strain B14T (=DSM 116946T=LMG 33352T) represents a novel species of the genus Roseobacter for which the name Roseobacter fucihabitans sp. nov. is proposed.

Anaerobaca lacustris gen. nov., sp. nov., an obligately anaerobic planctomycete of the widespread SG8-4 group, isolated from a coastal lake, and proposal of Anaerobacaceae fam. nov

One of the numerous and widespread lineages of planctomycetes is the hitherto uncultured SG8-4 group inhabiting anoxic environments. A novel anaerobic, mesophilic, alkalitolerant, chemoorganotrophic bacterium (strain M17dextrT) was isolated from anaerobic sediment of a coastal lake (Taman Peninsula, Russia). The cell were mainly non-motile cocci, 0.3 to 1.0 µm in diameter forming chains or aggregates. The cells had a Gram-negative cell wall and divided by binary fission. The temperature range for growth was 20–37 0C (optimum at 30 0C). The pH range for growth was 6.5–10.0, with an optimum at pH 8.0–8.5. Strain M17dextrT fermented mono-, di- and polysaccharides (starch, xanthan gum, dextran, N-acetylglucosamine), but did not utilized proteinaceous compounds. Major cellular fatty acids were C16:0 and C18:0. The genome of strain M17dextrT had a size of 5.7 Mb with a G + C content of 62.49 %. The genome contained 345 CAZyme genes. The closest cultured phylogenetic relatives of strain M17dextrT were members of the order Sedimentisphaerales, class Phycisphaerae. Among characterized planctomycetes, the highest 16S rRNA gene sequence similarity (88.3 %) was observed with Anaerohalosphaera lusitana. According to phylogenomic analysis strain M17dextrT together with many uncultured representatives of Sedimentisphaerales forms a separate family‐level lineage. We propose to assign strain M17dextrT to a novel genus and species, Anaerobaca lacustris gen. nov., sp. nov.; the type strain is M17dextrT (=VKM B-3571 T = DSM 113417 T = JCM 39238 T = KCTC 25381 T = UQM 41474 T). This genus is placed in a novel family, Anaerobacaceae fam. nov. within the order Sedimentisphaerales.

Date pomace polysaccharide: ultrasonic-assisted deep eutectic solvent extraction, physicochemical properties, biological activities, gut microbiota modulation, and rheological properties

BackgroundThis study utilized ultrasonication-assisted green extraction techniques to explore the physicochemical, rheological, biological, and prebiotic properties, alongside gut modulation abilities of novel polysaccharides extracted from date pomace. The extraction aimed at enhancing the utilization of date pomace, a by-product of date fruit processing, by investigating its potential as a functional food ingredient. The research focused on optimizing the extraction process, understanding the complex structure of the polysaccharides, and assessing their various health-related functionalities.ResultsThe ultrasonically extracted polysaccharides (UPS) were identified as a mixture of significant bioactive compounds including galacturonic acid, galactose, glucose, arabinose, and fructose, showcasing a high molecular weight of 537.7 kDa. The study found that UPS exhibited outstanding antioxidant activities, with scavenging abilities ranging from 59 to 82% at a concentration of 1000 mg/L. Additionally, UPS demonstrated potent inhibitory effects on α-amylase (83%), α-glucosidase (81%), and ACE-inhibition (45%), alongside strong antiproliferative activities against Caco-2 and MCF-7 cancer cell lines and broad-spectrum antimicrobial properties. Remarkably, UPS also enhanced the abundance of beneficial gut microbiota, including Actinobacteria, Firmicutes, and Proteobacteria, during in vitro fermentations and positively modulated gut metabolic pathways, promoting the production of major short-chain fatty acids. UPS had higher abundance in pathways related to cofactors, vitamins, electron carriers, and prosthetic groups biosynthesis compared to blank.ConclusionsThe findings affirm the potential of UPS extracted from date pomace as an innovative and promising functional food ingredient. Its high molecular weight, complex sugar composition, significant antioxidant, antimicrobial, antiproliferative activities, and prebiotic properties make it a valuable resource for promoting health and managing diseases. This study paves the way for further research on the bioavailability and physiological effects of UPS in vivo, highlighting the importance of sustainable utilization of agricultural by-products in developing functional foods that support human health.Graphical

Klenkia sesuvii sp. nov., isolated from leaves of halophyte Sesuvium portulacastrum.

During a study on the diversity of culturable actinobacteria from coastal halophytes in Thailand, strain LSe6-5T was isolated from leaves of sea purslane (Sesuvium portulacastrum L.), and a polyphasic approach was employed to determine its taxonomic position. The 16S rRNA gene sequences analysis indicated that the strain was most closely related to Klenkia brasiliensis Tu 6233T (99.2 %), Klenkia marina YIM M13156T (99.1 %), and Klenkia terrae PB261T (98.7 %). The genome of strain LSe6-5T was estimated to be 4.33 Mbp in size, with DNA G+C contents of 74.3%. A phylogenomic tree based on whole-genome sequences revealed that strain LSe6-5T formed a clade with Klenkia marina DSM 45722T, indicating their close relationship. However, the average nucleotide identity (ANI)-blast, ANI-MUMmer, and dDDH values between strain LSe6-5T with K. marina DSM 45722T (87.1, 88.9, and 33.0 %) were below the thresholds of 95-96 % ANI and 70 % dDDH for identifying a novel species. Furthermore, strain LSe6-5T showed morphological and chemotaxonomic characteristics of the genus Klenkia. Cells were motile, rod-shaped, and Gram-stain-positive. Optimal growth of strain LSe6-5T occurred at 28 °C, pH 7.0, and 0-3 % NaCl. The whole-cell hydrolysates contained meso-diaminopimelic acid as the diagnostic diamino acid, with galactose, glucose, mannose, and ribose as whole-cell sugars. The predominant menaquinones were MK-9(H4) and MK-9(H0). The polar lipid profile was composed of diphosphatidylglycerol, hydroxyphosphatidylethanolamine, phosphatidylinositol, glycophosphatidylinositol, an unidentified phospholipid, and an unidentified lipid. Major cellular fatty acids were iso-C15 : 0, iso-C16 : 0, and iso-C17 : 0. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, it is supported that strain LSe6-5T represents a novel species of the genus Klenkia, for which the name Klenkia sesuvii sp. nov. is proposed. The type strain is strain LSe6-5T (=TBRC 16417T= NBRC 115929T).

Lysobacter stagni sp. nov. and Limnohabitans lacus sp. nov., isolated from a pond.

Two Gram-negative bacteria, designated as strains LF1T and HM2-2T, were isolated from an artificial pond in a honey farm at Hoengseong-gun, Gangwon-do, Republic of Korea. The 16S rRNA sequence analysis results revealed that strain LF1T belonged to the genus Lysobacter and had the highest sequence similarity to Lysobacter niastensis GH41-7T (99.0 %), Lysobacter panacisoli CJ29T (98.9 %), and Lysobacter prati SYSU H10001T (98.2 %). Its growth occurred at 20-37 °C, at pH 5.0-12.0, and in the presence of 0-2% NaCl. The major fatty acids were iso-C15 : 0, iso-C16 : 0, and summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The DNA G+C content was 67.5 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain LF1T and species of the genus Lysobacter were 79.1-84.4% and 22.0-27.5 %, respectively. The 16S rRNA sequence analysis results revealed that strain HM2-2T belonged to the genus Limnohabitans and was most closely related to Limnohabitans planktonicus II-D5T (98.9 %), Limnohabitans radicicola JUR4T (98.4%), and Limnohabitans parvus II-B4T (98.4 %). Its growth occurred at 10-35 °C, at pH 5.0-11.0, and in the presence of 0-2% NaCl. The major fatty acids were C16 : 0 and summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c). The major polar lipid was phosphatidylethanolamine. The DNA G+C content was 59.9 mol%. The ANI and dDDH values between strain HM2-2T and its closely related strains were 75.1-83.0% and 20.4-26.4 %, respectively. Phenotypic, genomic, and phylogenetic data revealed that strains LF1T and HM2-2T represent novel species in the genera Lysobacter and Limnohabitans, for which the names Lysobacter stagni sp. nov. and Limnohabitans lacus sp. nov. are proposed, respectively. The type strain of Lys. stagni is LF1T (=KACC 23251T=TBRC 17648T), and that of Lim. lacus is HM2-2T (=KACC 23250T=TBRC 17649T).

Sex-based Differences in Fatty Acids and Macro Elements Composition in Garfish, European Barracuda and Anglerfish from Aegean Sea, Türkiye

Background: Fish, owing to its nutritional attributes, serves as a pivotal component of a wholesome diet. The constituents found in fish, specifically macroelements and polyunsaturated fatty acids (PUFA), play a crucial role in promoting human health. This study investigates the fatty acid profiles and macro element contents of economically significant fish species, including garfish (Belone belone), European barracuda (Sphyraena sphyraena) and anglerfish (Lophius piscatorius), with a specific focus on gender-based differences. The research addresses a notable gap in existing literature, providing a comprehensive evaluation of the nutritional quality of these species. Methods: In February 2023, marine fish species, were obtained from the Aegean Sea located between the western and southwestern shores of Türkiye and the eastern shores of Greece. A total of fifteen samples, representing each fish species and gender within the sampling area, were collected for the analysis of fatty acids and macro elements. Result: The findings of this study indicate that, regardless of fish species and gender, the major fatty acids in the SFAs, MUFAs and PUFAs classes were palmitic (C16:0), oleic (C18:1n-9) and DHA (C22:6n-3), respectively. The examined species in this study exhibit average macro element levels. While PUFA, EPA and DHA values meet target levels of content for human health and quality food consumption, achieving these levels minimally implies that the studied species lack a rich fatty acid profile compared to those in prior research. Nonetheless, it is concluded that monitoring seasonal variations is essential for a comprehensive understanding of their fatty acid composition.

Changes in Fatty Acid Profiles in Seeds of Camellia oleifera Treated by Mycorrhizal Fungi and Glomalin

Camellia oleifera is an important oilseed forest tree, but it is unknown whether and how inoculation with arbuscular mycorrhizal fungi, as well as spraying easily extractable glomalin-related soil protein (EG), regulates the fatty acid profile in seeds of this species. This study explored how inoculation with Rhizophagus intraradices (800 g inoculum/tree) and spraying EG (2.5 L/tree, four times in total, once a week) modulated the fatty acid profile for potential nutritional qualities in the seeds of 20-year-old C. oleifera. Spraying exogenous EG significantly increased fruit transverse diameter, longitudinal diameter, fruit weight, number of seeds, and seed weight but had no significant effect on the root mycorrhizal colonization rate. Inoculation with R. intraradices had no significant effect on these fruit traits but significantly boosted the root mycorrhizal colonization rate. A total of 11 saturated fatty acids and 12 unsaturated fatty acids were detected from the seeds, with the unsaturated fatty acids consisting primarily of C18:1N-12, C18:1N-9C, and C18:2-N6. Spraying exogenous EG significantly increased the levels of major unsaturated fatty acid components such as C18:1N-12, C18:1N-9C, C18:1N-7, and C18:2N-6 by 140.6%, 59.7%, 97.6%, and 60.6%, respectively, while decreasing the level of C16:0. Inoculation with R. intraradices only decreased the levels of C16:0 and C18:0, while increased the level of C18:2N-6. Both treatments increased the percentage of unsaturated fatty acids in total fatty acids, resulting in an increase in the unsaturation index of fatty acids. In addition, inoculation with R. intraradices significantly up-regulated the expression of CoFAD2, spraying exogenous EG significantly increased the expression of CoSAD, CoFAD2, and CoFAD3, and both treatments also significantly suppressed the expression of CoFAE. These findings suggested that exogenous EG as a biostimulant, is more suitable to regulate the nutritional values of fatty acids in seeds of 20-year-old C. oleifera.

Comprehensive biochemical analysis and nutritional evaluation of fatty acid and amino acid profiles in eight seahorse species (Hippocampus spp.)

Seahorses are increasingly recognized for their nutritional potential, which underscores the necessity for comprehensive biochemical analyses. This study aims to investigate the fatty acid and amino acid compositions of eight seahorse species, including both genders of Hippocampus trimaculatus, Hippocampus kelloggi, Hippocampus abdominalis, and Hippocampus erectus, to evaluate their nutritional value. We employed Gas Chromatography-Mass Spectrometry (GC-MS) and High-Performance Liquid Chromatography (HPLC) to analyze the fatty acid and amino acid profiles of the seahorse species. GC-MS was used to detect 34 fatty acid methyl esters, while HPLC provided detailed amino acid profiles. GC-MS analysis demonstrated high precision with relative standard deviations (RSDs) generally below 2.53 %, satisfactory repeatability (RSDs from 6.55 % to 8.73 %), and stability (RSDs below 2.82 %). Recovery rates for major fatty acids ranged from 98.73 % to 109.12 %. HPLC analysis showed strong separation of amino acid profiles with theoretical plate numbers exceeding 5000. Precision tests yielded RSDs below 1.23 %, with reproducibility and stability tests showing RSDs below 2.73 % and 2.86 %, respectively. Amino acid recovery rates ranged from 97.58 % to 104.66 %. Nutritional analysis revealed significant variations in fatty acid content among the species. Female H. erectus showed higher levels of hexadecanoic acid and saturated fatty acids, while male H. abdominalis had lower concentrations of n-3 full cis 4,7,10,13,16,19-docosahexaenoic acid (DHA). Total lipid yields varied from 3.2491 % to 12.3175 %, with major fatty acids constituting 17.9717 %–74.6962 % of total lipids. In conclusion, this study provides essential insights into the fatty acid and amino acid composition of seahorses, supporting their potential as valuable dietary supplements. The differences between genders in specific fatty acids suggest a nuanced nutritional profile that could be exploited for targeted dietary applications. Further research is needed to explore the seasonal and environmental variations affecting seahorse biochemical composition.

Roseateles subflavus sp. nov. and Roseateles aquae sp. nov., isolated from artificial pond water and Roseateles violae sp. nov., isolated from a Viola mandshurica root.

Two novel strains, designated APW6T and APW11T, were isolated from artificial pond water, and one novel strain, designated PFR6T, was isolated from a Viola mandshurica root. These strains were found to be Gram-negative, rod-shaped, motile by means of flagella, and oxidase-positive. Growth conditions of the type strains were as follows: APW6T, 15-43 °C (optimum, 28 °C), pH 6.0-12.0 (optimum, pH 7.0), with no salinity; APW11T, 4-35 °C (optimum, 25 °C), pH 6.0-11.0 (optimum, pH 9.0), with 0-1 % NaCl (w/v, optimum 0 %); PFR6T, 10-38 °C (optimum 28 °C), pH 6.0-12.0 (optimum, pH 7.0), with 0-2 % NaCl (w/v; optimum, 0 %). Strains APW6T, APW11T, and PFR6T belonged to the genus Roseateles, having the most 16S rRNA gene sequence similarity to Roseateles saccharophilus DSM 654T (98.1 %), Roseateles oligotrophus CHU3T (98.7 %), and Roseateles puraquae CCUG 52769T (98.1 %). The estimated genome sizes of APW6T, APW11T, and PFR6T were 50 50 473, 56 70 008, and 52 16 869 bp, respectively and the G+C contents were 69.5, 66, and 68.5 mol%. The digital DNA-DNA hybridization, average amino acid identity, and average nucleotide identity values among the novel strains and related taxa were all lower than 22.4, 74.7, and 78.9 %, respectively. The predominant cellular fatty acids (>10 %) of all strains were summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. PFR6T also had summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) as a major fatty acid. The polar lipid profile of all strains contained phosphatidylethanolamine, phosphoaminoglycolipid, and phosphoglycolipid. The distinct phylogenetic, physiological, and chemotaxonomic features reported in this study indicate that strains APW6T, APW11T, and PFR6T represent novel species within the genus Roseateles, for which the names Roseateles subflavus sp. nov., with the type strain APW6T (=KACC 22877T=TBRC 16606T), Roseateles aquae sp. nov., with the type strain APW11T (=KACC 22878T=TBRC 16607T), and Roseateles violae sp. nov (=KACC 23257T=TBRC 17653T) are respectively proposed.

Hwangdonia lutea sp. nov., isolated from the Haima cold seep, South China Sea.

A Gram-stain-negative, orange-yellow, rod-shaped bacterium, designated strain SCSIO 19198T, was isolated from sediment of the Haima cold seep in the South China Sea, PR China. The strain was aerobic and non-motile. Growth of strain SCSIO 19198T occurred at pH 7-9 (optimum, pH 7), 15-37 °C (optimum, 25-32 °C) and with 3-8 % (w/v) NaCl (optimum, 3-6 % NaCl). Phylogenetic analyses based on 16S rRNA sequences revealed that strain SCSIO 19198T belonged to the genus Hwangdonia, having the highest similarity to Hwangdonia seohaensis HD-3T (98.35 %), followed by Algibacter aquimarinus KYW589T (95.17 %) and Gelatiniphilus marinus GYP-24T (94.89 %). The DNA G+C content was 35.92 mol%. The average nucleotide identity value between the genome of strain SCSIO 19198T and that of H. seohaensis HD-3T was 88.49 %. The digital DNA-DNA hybridization value between strain SCSIO 19198T and H. seohaensis HD-3T was 36 %. The major fatty acids (>10 %) of strain SCSIO 19198T were iso-C15 : 0, iso-C15 : 1 G, summed feature 3 (C16 : 1 ω6c/C16 : 1 ω7c) and anteiso-C15 : 0. MK-6 was the only detected respiratory quinone. The polar lipids of strain SCSIO 19198T included phosphatidylethanolamine, two aminolipids, glycolipid and two unidentified lipids. The phenotypic, phylogenetic, chemotaxonomic and genomic data clearly suggest that strain SCSIO 19198T represents a novel species of the genus Hwangdonia, for which the name Hwangdonia lutea sp. nov. is proposed. The type strain is SCSIO 19198T (=MCCC 1K08674T=KCTC 102078T).