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Anti-androgenetic effect of diphlorethohydroxycarmalol on testosterone-induced hair loss by inhibiting 5α-reductase and promoting Wnt/β-catenin signaling pathway in human dermal papilla cells
No full textDiphlorethohydroxycarmalol (DPHC), a marine phlorotannin compound derived from the brown alga Ishige okamurae, has been known to have a variety of biological effects. Recently, marine resources have been highlighted by their effects on ameliorating alopecia and related hair loss. Therefore, this study aimed to investigate the potential of DPHC isolated from I. okamurae as a hair loss treatment through examination of its anti-androgenic alopecia effects. Molecular docking analysis predicted that DPHC can be used as a 5α-reductase inhibitor superior to finasteride, which has traditionally been used as an anti-androgenic alopecia agent. In addition, DPHC significantly inhibited 5α-reductase activity in dihydrotestosterone (DHT)-treated human dermal papilla (HDP) cells, and downregulated hair growth inhibitor proteins such as AR, DKK1, TGF-β1, and IL-6. Moreover, DPHC treatment remarkably upregulated both the phosphorylation levels of GSK3β and expression levels of β-catenin in DHT-treated HDP cells, confirming the effects of DPHC on activating the Wnt/β-catenin signaling pathway. Therefore, these findings suggest that DPHC has a significant potential to prevent androgenic alopecia by promoting hair growth and preventing hair loss.11Nsciescopu
Quantitative Real-Time Polymerase Chain Reaction (PCR) Assay for Rapid Monitoring of the Harmful Algal Bloom Species Cochlodinium polykrikoides
No full textHarmful blooms of the dinoflagellate Cochlodinium polykrikoides (Margalefidinium polykrikoides) had detrimental aquacultural and economic effects globally, and to reduce the damage caused by these blooms, early biomonitoring and quantitative analysis of C. polykrikoides are of the utmost importance. Here, for the detection of C. polykrikoides using quantitative real-time polymerase chain reactions, we developed specific primers targeting the large subunit ribosomal DNA (LSU rDNA) and evaluated their applicability in the field during the occurrence of a C. polykrikoides bloom. The specific primers not only accurately detected C. polykirkoides but also had a detection performance comparable with that obtained using microscopic observations. Accordingly, we developed a system that can be used in the field and applied when red tides occur, with accurate results being obtained more than five times more rapidly than those obtained based on microscopic analysis. Collectively, our findings indicate that the C. polykrikoides bloom detection system developed in this study can be applied to rapidly detect and accurately quantify C. polykrikoides in environmental samples. Data obtained using this system could be used as a basis for developing prompt monitoring and warning systems for the early detection of C. polykrikoides blooms in the field.11Ysciescopu
Exploration of formate as a liquid organic hydrogen carrier in biohydrogen production through evolutionary and process engineering of hyperthermophilic archaeon
No full textHydrogen (H2) is considered a promising renewable energy source, but its storage and delivery present significant challenges. Liquid organic hydrogen carriers (LOHC) offer a potential solution to this problem, with formate as a top candidate for LOHC. This study focused on developing technology for biological H2 production from formate by utilizing the hyperthermophilic archaeon Thermococcus onnurineus NA1. An engineered strain, WTF-350 T, was developed through adaptive evolution using formate and exhibited 3.6–4.0 times enhanced cell growth, formate consumption, and H2 production compared to the wild-type strain. Optimizing fermentation processes through pH-stat, fed-batch mode, and pyruvate supplementation led to a 2.0–2.5 times increase in cell density and H2 production rate. Moreover, formic acid, produced by the electroreduction of carbon dioxide (CO2), was found to be an effective feedstock for biohydrogen production. This study successfully demonstrated the potential of integrating CO2 electroreduction and biohydrogen production for a sustainable hydrogen economy.11Nsciescopu
Co-occurrence patterns between Chlorophyta and nucleocytoplasmic large DNA virus in coastal ecosystem, South Korea
No full textNucleocytoplasmic large DNA viruses (NCLDVs) are known to infect phytoplankton and play a significant role in regulating their population dynamics. In this study, we aimed to investigate the co-occurrence patterns between phytoplankton and NCLDVs in the southern coastal ecosystem of South Korea. We collected seawater every month from March 2018 to December 2020 and analyzed the samples using Cytochrome c Oxidase subunit I metabarcoding and metagenomic analyses. Chlorophyta (36.08%) was the most abundant eukaryotic taxon, with Bathycoccaceae (58.25%) and Mamiellaceae (41.51%) being the most dominant families within Chlorophyta. Bathycoccaceae was dominant in winter, whereas Mamiellaceae was dominant in summer. In the NCLDV community, Phycodnaviridae (75.12%) was found to be the major family. The co-occurrence pattern of Phycodnaviridae showed a high correlation with Bathycoccaceae and Mamiellaceae, which is explained by the “boom-and-bust” concept. In particular, we predicted co-occurrence patterns between Bathycoccus prasinos and Prasnovirus, with known infectious relationships, and confirmed co-occurrence patterns between B. prasinos and Coccolithovirus and Micromonas pusilla and Prymnesiovirus, with unknown infectious relationships. These co-occurrence patterns between Chlorophyta and Phycodnaviridae provide valuable insights into the control of pico-sized primary production and the microbial loop of the coastal ecosystem.11Nsciescopu
Unraveling the unique bioactivities of highly purified C-phycocyanin and allophycocyanin
No full textBackground
The blue-green microalgae Spirulina, used in human nutrition for centuries, includes phycobiliproteins such as C-phycocyanin (CPC) and allophycocyanin (APC). Assessing their unique bioactivities separately is difficult as they have similar properties, such as molecular weight and isoelectric point. In the present study, we aimed to separate CPC and APC and to evaluate their bioactivities. CPC and APC were separated using a hydrophobic membrane and ammonium sulfate, which promotes reversible and specific protein binding to the membrane. Spectroscopic analysis, HPLC, and SDS-PAGE revealed a successful separation of CPC and APC. Their bioactivities were evaluated through CCK- 8 assays for anticancer activity, radical scavenging assays for antioxidant activity, and albumin denaturation assays for anti-inflammatory activity, respectively.
Results
The results revealed that highly purified APC showed 40% higher anticancer activity than the control, whereas CPC increased the viability of cancer cells, resulting in a 30% decrease in anticancer activity compared to the control. In contrast, highly purified CPC showed approximately 25% higher antioxidant activity and twice as much anti-inflammatory activity as APCs; moreover, the presence of both showed higher antioxidant activity.
Conclusion
This study provides important insights into the unique bioactivities of CPC and APC for their appropriate application as anticancer, antiphlogistic, and antioxidant agents.11Ysciescopu
CONTROL APPARATUS FOR REMOVABLE SUCTION ANCHOR SYSTEM USING WATER PRESSURE
No full text본 발명은 찰탈식 석션앵커시스템에서 석션/인발을 위한 버터플라이 밸브의 방향전환을 밸브팩를 유압이
아닌 수압을 사용하는 회로를 구성함으로써 유압유 누유로 인한 해양환경오염을 방지 할수 있다
Evaluation and Valorization of Ecological Risk Mitigation Through the Use of Sustainable Marine Resources in Ulva, a Marine Ecological Disturbance Species
No full textMassive blooms of Ulva species, commonly known as green tides, pose serious ecological threats by disrupting coastal ecosystems and requiring costly removal efforts. This study presents a nature-based solution by seasonally valorizing Ulva ohnoi, a bloom-forming macroalga dominant in Jeju Island, South Korea. Biomass was collected across all four seasons and subjected to phylogenetic identification, biochemical characterization, and bioresource processing. Despite environmental fluctuations, tufA-based analysis confirmed U. ohnoi as the sole species present year-round. Carbohydrate content peaked in spring (55.35%) and was lowest in summer (45.74%), corresponding to maximum reducing sugar of 36.49 g/L in winter and 36.24 g/L in spring following acid-enzymatic hydrolysis. The maximum ethanol fermentation using Saccharomyces cerevisiae produced up to 17.12 g/L ethanol in spring with a yield of 0.47 g/g. Post-fermentation residues were enzymatically hydrolyzed into Ulva Ethanol Residue Medium (UERM), which supported yeast growth and fermentation comparable to commercial YPD medium, achieving final optical densities of 8.3-8.5 and ethanol production of 16.5-16.8 g/L. Alanine, valine, and proline were the most abundant amino acids in UERM, supporting its suitability as a nitrogen source. These findings highlight the potential of integrating green tide mitigation with renewable energy and nutrient recycling through seasonal, localized biorefineries aligned with circular marine bioeconomy principles.11Nsciescopu
Assessment of Exploited Stock and Management Implications of Tiger Tooth Croaker (Otolithes ruber) in Coastal Waters of Makran, Pakistan
No full textPakistan’s marine fishing industry is crucial to the country’s economy, generating employment opportunities and foreign revenue. It produces 80% of the country’s total fish production. Otolithes ruber is a commercially important fish on the Makran coast of Pakistan, contributing significantly to the region’s croaker fisheries. This study is the first to apply three length-based approaches for assessing the stock status of O. ruber in the Makran coast: (1) TropFishR to estimate the mortality, growth parameters, and current exploitation status, reference points based on the yield per recruitment model, (2) the length-based Bayesian biomass method (LBB) to calculate stock biomass, and (3) the length-based spawning potential ratio (LBSPR) to estimate the spawning potential ratio. The length–weight relationship of Otolithes ruber was a positive allometric pattern (b = 3.28; R2 = 0.94). Growth parameters for Otolithes ruber were L∞ = 55.47 cm, K = 0.50 year−1. The calculated total mortality rate (Z), natural mortality (M), and fishing mortality (F) were 2.27 year−1, 0.67 year−1, and 1.6 year−1, respectively. The exploitation rate (E) was 0.70, indicating severe overexploitation. The current length at first capture (Lc50) = 27.37 cm was lower than that at first maturity (Lm50) = 30.75 cm, indicating growth overfishing. The current spawning potential ratio (8%) was lower than the optimal value (40%), indicating recruitment overfishing. The current biomass, concerning virgin biomass B/Bo, was also 8%, resulting in a 92% stock decline. We recommend reducing the exploitation pressure by limiting the commercial catch to an optimum length range of 34.5–42.2 cm and reducing fishing pressure by 40% to ensure sustainable fishery management.11Nsciescopu
The impacts of climate change on the physiology and ecology of the top shell, Turbo sazae
No full textThis study synthesizes recent findings on how the top shell, Turbo sazae, responds to climate change through physiological, dietary, and genetic adaptations. Elevated seawater temperatures negatively affect immune functions, as indicated by decreased phagocytosis
capacity and heightened oxidative stress. Despite this thermal challenge, T. sazae demonstrates resilience in altered benthic ecosystems, where rising temperatures drive macroalgal depletion and the proliferation of calcareous algae. Experimental feeding trials revealed that individuals maintained comparable immunological health, reproductive development, and growth rates when consuming either macroalgae (Ecklonia cava) or calcareous algae (Corallina officinalis), although shifts in amino acid profiles were observed. In tandem with these physiological and dietary responses, genetic analyses based on mitochondrial COI sequences elucidate strong connectivity among populations in Jeju Island and the East/Japan Sea, facilitated by larval dispersal through major oceanic currents. Nonetheless, localized genetic ifferentiation suggests potential barriers to gene flow in specific regions. These findings collectively indicate that T. sazae is undergoing a northward range expansion, tracking warmer waters at an estimated rate of 12.4 km per year. The integrative evidence underscores the species' remarkable adaptability yet highlights the importance of targeted conservation strategies to safeguard unique genetic lineages and promote sustainable management in a rapidly changing marine environment.1
Overview of the development of demonstration test evaluation technology for unmanned maritime systems
No full text해양 무인시스템은 사람이 탑승하지 않고 외부환경을 스스로 인식하여 일정이상의 자율적 임무를 수행하는 시스템을 통칭하는 개념이다. 무인시스템은 이미 국내에서 다양하게 사용되고 있으며 상용화 기술이 발전해 가는 추세이다. 하지만 해외에서는 해양로봇 기술 검증 및 운용 기술 평가를 위한 시험장을 운영하는 데 반하여 국내에서 개발되고 있는 해양로봇은 실해역의 실증 시험의 어려움과 평가·인증 시설의 부재로 실용화 사례가 극히 미미한 실적이다. 본 연구개발에서는 해양 무인시스템의 수조/내해/외해의 시험 평가기술을 수립하고 단체표준 제정안을 수행한다. 민∙관∙군 협의체의 구성을 통해 해양 무인시스템의 활용성을 제고하고 실 수요자를
위한 시험평가기술을 개발한다. 시험평가기술의 절차서를 개발하고 오픈랩을 구성한다. 마지막으로 법제도 구성 방안 연구를 통해 해양 무인시스템 산업 활성화에 선제적으로 대응한다.2