Complete genome sequence of Levilactobacillus brevis NSMJ23, makgeolli isolate with antimicrobial activity

We report the complete genome sequence of Levilactobacillus brevis NSMJ23 with probiotic properties. The final genome assembly consisted of a 2,389,998-bp chromosome and seven plasmids with 45.59% GC content, which comprised 2,624 genes including 2,457 protein coding sequences.

Intestinal Immune Cell Populations, Barrier Function, and Microbiomes in Broilers Fed a Diet Supplemented with Chlorella vulgaris

This study aimed to evaluate the effects of dietary Chlorella vulgaris (CV) on the distribution of immune cells, intestinal morphology, intestinal barrier function, antioxidant markers, and the cecal microbiome in 10-day-old broiler chickens. A total of 120 day-old Ross 308 male broiler chicks were assigned to two dietary treatments using a randomized complete block design, with body weight as the blocking factor. Birds fed a diet containing CV showed an increase in CD4⁺ T cells (p < 0.05) compared to those fed the control diet. The relative mRNA expression of intestinal epithelial barrier function-related markers (occludin and avian β-defensin 5) was elevated (p < 0.05) in the CV-supplemented group compared to the control group. The alpha diversity indices (Chao1 and observed features) of the cecal microbiome in 10-day-old birds increased (p < 0.05), indicating higher richness within the cecal bacterial community. In the microbiome analysis, enriched genera abundance of Clostridium ASF356 and Coriobacteriaceae CHKCI002 was observed in birds fed the diet containing CV compared to those fed the control diet. Taken together, dietary CV supplementation might alter intestinal barrier function, immunity, and microbiomes in 10-day-old broiler chickens.

Effect of Dietary Chlorella vulgaris or Tetradesmus obliquus on Laying Performance and Intestinal Immune Cell Parameters

A feeding trial was conducted to investigate the effect of dietary supplementation of Chlorella vulgaris (CV) or Tetradesmus obliquus (TO) on laying performance, egg quality, and gut health indicators of laying hens. A total of 144 Hy-Line Brown laying hens aged 21 weeks were randomly assigned to one of three dietary treatments with eight replicates of six hens. Dietary treatments were as follows: CON, basal diet; CV, basal diet + 5 g C. vulgaris/kg of diet; TO, basal diet + 5 g T. obliquus/kg of diet. The results showed that diets supplemented with CV or TO had insignificant effects on laying performance, egg quality (i.e., Haugh unit and eggshell strength and thickness), jejunal histology, cecal short-chain fatty acids, and antioxidant/immune markers in ileal mucosa samples of laying hens. Compared with the control group, the egg yolk color score was higher (p < 0.05) in laying hens fed on diets containing CV and TO, although the former was a more intense yellow than the latter. Small intestinal lamina propria cells were isolated using flow cytometry to examine the percentages of immune cell subpopulations. Dietary microalgae did not affect B cells or monocytes/macrophages but altered the percentage of CD4+ T cells and CD8- TCR γδ T cells. Collectively, diets supplemented with C. vulgaris or T. obliquus can improve egg yolk color and would modulate host immune development and competence in laying hens.

Improvement of Lutein and Zeaxanthin Production in Mychonastes sp. 247 by Optimizing Light Intensity and Culture Salinity Conditions

In this study, we sought to improve lutein and zeaxanthin production in Mychonastes sp. 247 and investigated the effect of environmental factors on lutein and zeaxanthin productivity in Mychonastes sp. The basic medium selection and N:P ratio were adjusted to maximize cell growth in one-stage culture, and lutein and zeaxanthin production conditions were optimized using a central composite design for two-stage culture. The maximum lutein production was observed at a light intensity of 60 μE/m²/s and salinity of 0.49%, and the maximum zeaxanthin production was observed at a light intensity of 532 μE/m²/s and salinity of 0.78%. Lutein and zeaxanthin production in the optimized medium increased by up to 2 and 2.6 folds, respectively, compared to that in the basic medium. Based on these results, we concluded that the optimal conditions for lutein and zeaxanthin production are different and that optimization of light intensity and culture salinity conditions may help increase carotenoid production. This study presents a useful and potential strategy for optimizing microalgal culture conditions to improve the productivity of lutein and zeaxanthin, which has applications in the functional food field.

Mychonastes sp. 246 Suppresses Human Pancreatic Cancer Cell Growth via IGFBP3- PI3K-mTOR Signaling

Previously, we confirmed that Mychonastes sp. 246 methanolic extract (ME) markedly reduced the viability of BxPC-3 human pancreatic cancer cells. However, the underlying mechanism ME remained unclear. Hence, we attempted to elucidate the anticancer effect of ME on BxPC-3 human pancreatic cancer cells. First, we investigated the components of ME and their cytotoxicity in normal cells. Then, we confirmed the G1 phase arrest mediated growth inhibitory effect of ME using a cell counting assay and cell cycle analysis. Moreover, we found that the migration-inhibitory effect of ME using a Transwell migration assay. Through RNA sequencing, Gene Ontology-based network analysis, and western blotting, we explored the intracellular mechanisms of ME in BxPC-3 cells. ME modulated the intracellular energy metabolism-related pathway by altering the mRNA levels of IGFBP3 and PPARGC1A in BxPC-3 cells and reduced PI3K and mTOR phosphorylation by upregulating IGFBP3 and 4E-BP1 expression. Finally, we verified that ME reduced the growth of three-dimensional (3D) pancreatic cancer spheroids. Our study demonstrates that ME suppresses pancreatic cancer proliferation through the IGFBP3-PI3K-mTOR signaling pathway. This is the first study on the anticancer effect of the ME against pancreatic cancer, suggesting therapeutic possibilities and the underlying mechanism of ME action.

Gossypol Induces Apoptosis of Human Pancreatic Cancer Cells via CHOP/Endoplasmic Reticulum Stress Signaling Pathway

Gossypol, a natural phenolic aldehyde present in cotton plants, was originally used as a means of contraception, but is currently being studied for its anti-proliferative and anti-metastatic effects on various cancers. However, the intracellular mechanism of action regarding the effects of gossypol on pancreatic cancer cells remains unclear. Here, we investigated the anti-cancer effects of gossypol on human pancreatic cancer cells (BxPC-3 and MIA PaCa-2). Cell counting kit-8 assays, annexin V/propidium iodide staining assays, and transmission electron microscopy showed that gossypol induced apoptotic cell death and apoptotic body formation in both cell lines. RNA sequencing analysis also showed that gossypol increased the mRNA levels of CCAAT/enhancer-binding protein homologous protein (CHOP) and activating transcription factor 3 (ATF3) in pancreatic cancer cell lines. In addition, gossypol facilitated the cleavage of caspase-3 via protein kinase RNA-like ER kinase (PERK), CHOP, and Bax/Bcl-2 upregulation in both cells, whereas the upregulation of ATF was limited to BxPC-3 cells. Finally, a three-dimensional culture experiment confirmed the successful suppression of cancer cell spheroids via gossypol treatment. Taken together, our data suggest that gossypol may trigger apoptosis in pancreatic cancer cells via the PERK-CHOP signaling pathway. These findings propose a promising therapeutic approach to pancreatic cancer treatment using gossypol.

Enhanced Production of Fatty Acids via Redirection of Carbon Flux in Marine Microalga Tetraselmis sp

Lipids in microalgae are energy-rich compounds and considered as an attractive feedstock for biodiesel production. To redirect carbon flux from competing pathways to the fatty acid synthesis pathway of Tetraselmis sp., we used three types of chemical inhibitors that can block the starch synthesis pathway or photorespiration, under nitrogen-sufficient and nitrogen-deficient conditions. The starch synthesis pathway in chloroplasts and the cytosol can be inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 1,2-cyclohexane diamine tetraacetic acid (CDTA), respectively. Degradation of glycine into ammonia during photorespiration was blocked by aminooxyacetate (AOA) to maintain biomass concentration. Inhibition of starch synthesis pathways in the cytosol by CDTA increased fatty acid productivity by 27% under nitrogen deficiency, whereas the blocking of photorespiration in mitochondria by AOA was increased by 35% under nitrogen-sufficient conditions. The results of this study indicate that blocking starch or photorespiration pathways may redirect the carbon flux to fatty acid synthesis.

Seasonal Assessment of Biomass and Fatty Acid Productivity by Tetraselmis sp. in the Ocean Using Semi-Permeable Membrane Photobioreactors

A green microalga, Tetraselmis sp., was cultivated in the coastal seawater of Young-Heung Island using semi-permeable membrane photobioreactors (SPM-PBRs) in different seasons. The microalgae in the SPM-PBRs were able to grow on nutrients diffused into the PBRs from the surrounding seawater through SPMs. The biomass productivity varied depending on the ion permeabilities of the SPMs and environmental conditions, whereas the quality and quantity of fatty acids were constant. The temperature of seawater had a greater influence than solar radiation did on productivity of Tetraselmis sp. in SPM-PBRs. SPM-PBRs could provide technologies for concurrent algal biomass and fatty acids production, and eutrophication reduction in the ocean.

Enhancing Photon Utilization Efficiency for Astaxanthin Production from Haematococcus lacustris Using a Split-Column Photobioreactor

A split-column photobioreactor (SC-PBR), consisting of two bubble columns with different sizes, was developed to enhance the photon utilization efficiency in an astaxanthin production process from Haematococcus lacustris. Among the two columns, only the smaller column of SC-PBR was illuminated. Astaxanthin productivities and photon efficiencies of the SC-PBRs were compared with a standard bubble-column PBR (BC-PBR). Astaxanthin productivity of SC-PBR was improved by 28%, and the photon utilization efficiencies were 28-366% higher than the original BC-PBR. The results clearly show that the effective light regime of SC-PBR could enhance the production of astaxanthin.

Conditioned medium derived from umbilical cord mesenchymal stem cells regenerates atrophied muscles

We investigated the regenerative effects and regulatory mechanisms of human umbilical cord mesenchymal stem cells (UC-MSCs)-derived conditioned medium (CM) in atrophied muscles using an in vivo model. To determine the appropriate harvest point of UC-CM, active factor content was analyzed in the secretome over time. A muscle atrophy model was induced in rats by hindlimb suspension (HS) for 2 weeks. Next, UC-CM was injected directly into the soleus muscle of both hind legs to assess its regenerative efficacy on atrophy-related factors after 1 week of HS. During HS, muscle mass and muscle fiber size were significantly reduced by over 2-fold relative to untreated controls. Lactate accumulation within the muscles was similarly increased. By contrast, all of the above analytical factors were significantly improved in HS-induced rats by UC-CM injection compared with saline injection. Furthermore, the expression levels of desmin and skeletal muscle actin were significantly elevated by UC-CM treatment. Importantly, UC-CM effectively suppressed expression of the atrophy-related ubiquitin E3-ligases, muscle ring finger 1 and muscle atrophy F-box by 2.3- and 2.1-fold, respectively. UC-CM exerted its actions by stimulating the phosphoinositol-3-kinase (PI3K)/Akt signaling cascade. These findings suggest that UC-CM provides an effective stimulus to recover muscle status and function in atrophied muscles.

Surface plasmon polariton detection discriminating the polarization reversal image dipole effects

Image dipole effects are highly dependent on the polarization direction, constructive (destructive) interference between real and image dipoles for the vertically (horizontally) aligned one in the vicinity of metal surfaces, respectively. This polarization-reversal of the image dipole effects is quantitatively investigated by using a gold nanoparticle functionalized tip as a local dipolar scatterer and a propagating surface plasmon polariton as an excitation source of dipoles. The polarization-resolved detection technique is applied to separate the radiations of the vertical and the horizontal dipoles from each other. In our study, the image dipole effects on the far-field detected signals are fully explained by the Fabry-Perot like interference between the radiations from the real and the image dipoles, and by considering the finite size effects of the gold nanoparticle.

Photofragment helicity caused by matter-wave interference from multiple dissociative states

Isolated diatomic molecules of iodine monochloride (ICl) were photodissociated by a beam of linearly polarized light, and the resulting ground-state Cl atom photofragments were detected by a method that is sensitive to the handedness (helicity) of the electronic angular momentum. It was found that this helicity oscillates between "topspin" and "backspin" as a function of the wavelength of the dissociating light. The helicity originates solely from the (de Broglie) matter-wave interference of multiple dissociating pathways of the electronic excited states of ICl. These measurements can be related to the identity and to the detailed shapes of the dissociating pathways, thus demonstrating that it is possible to probe repulsive states by spectroscopic means.

Femtosecond activation of reactions and the concept of nonergodic molecules

The description of chemical reaction dynamics often assumes that vibrational modes are well coupled (ergodic) and redistribute energy rapidly with respect to the course of the reaction. To experimentally probe nonergodic, nonstatistical behavior, studies of a series of reactions induced by femtosecond activation for molecules of varying size but having the same reaction coordinates [CH2 - (CH2)n-2 - C = Odagger --> products, with n = 4, 5, 6, and 10] were performed. Comparison of the experimental results with theoretical electronic structure and rate calculations showed a two to four orders of magnitude difference, indicating that the basic assumption of statistical energy redistribution is invalid. These results suggest that chemical selectivity can be achieved with femtosecond activation even at very high energies.