ScienceWatch@KIOST
Not a member yet
29648 research outputs found
Sort by
Projecting the poleward habitat expansion of whale sharks (Rhincodon typus) in the west pacific and east Indian ocean in response to climate change
No full textClimate change is accelerating the poleward redistribution of marine megafauna, including whale sharks. This study aimed to (1) identify suitable habitat beyond the whale shark’s known northern range in the Northwestern Pacific, (2) quantify projected shifts in habitat across the Western Pacific and Eastern Indian Ocean under future climate scenarios using species distribution models (SDMs), and (3) examine the influence of key environmental drivers across ecologically distinct regions using SHapley Additive exPlanations (SHAP) analysis. High-performing SDMs were developed using H2O AutoML, incorporating presence records from GBIF, OBIS, and newly documented sightings in Korean waters. The best-fitted model was hindcast (2004–2023) and forecasted for the 2050s, 2070s, and 2090s using CMIP6-based Earth System Models under three climate change scenarios. Model projections indicated substantial habitat losses in equatorial regions and concurrent poleward expansion. Predictions illuminated suitable habitat within Korean waters to 47°N under present ocean conditions, extending to nearly 50°N by the end of the century, largely due to increases in sea surface temperatures. In contrast, chlorophyll-a played a more influential role in shaping habitat suitability in the Philippines and Ningaloo Reef, indicating region-specific environmental controls. While Korean waters may emerge as a future aggregation hotspot, the Philippines are projected to experience a persistent decline in high-quality habitat, and Ningaloo Reef may undergo seasonal shifts in aggregation timing. These findings highlight the ecological importance of emerging habitats and the urgency for proactive, region-specific conservation strategies in response to climate-driven range shifts.11Nsciescopu
Development of a Multiplex One-step RT-qPCR Diagnostic Test for SARSCoV-2 Using a Portable Biomeme Thermocycler
No full textCoronavirus disease-19 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), poses a critical public health threat due to its high trans- missibility, infectivity, and prolonged incubation in humans. Timely identification of SARS-CoV-2 is crucial to control COVID-19 in the lack of effective antiviral medications in low resource regions. However, an accurate assay and portable diag- nostic method for SARS-CoV-2 remains to be developed. To address this issue, we developed a multiplex one-step reverse transcription quantitative polymerase chain reaction (RT-qPCR) for diagnosis of SARS-CoV-2 using a portable Biomeme Franklin™ Real-Time PCR thermocycler. The performance of the Biomeme assay was evaluated and validated for the testing of SARS-CoV-2 based on multiplex detection of the nucleocapsid, envelope, and spike genes. The Biomeme assay demonstrated high sensitivity by detecting the RNA of wild type 19 A and multiple SARS-CoV-2 variants, including B.1.617.2, BA.1, BA.2, BA.2.75, BA.5, and BN.1 from 0.01 ng/μl of total RNA and showed no cross-reactivity with other human coronaviruses, such as HCoV-OC43, HCoV-NL63, and HCoV-229E. The diagnostic method exhibited an analytical sensitivity of 95% and a specificity of 100%. The Biomeme Franklin platform generates rapid results within 3-4 h and allows smartphone-based output quantification, making it highly suitable as a Point of Care (POC) diagnostic tool. Therefore, this study reports on a diagnostic testing method for the prompt and reliable molecular diagnosis of SARS-CoV-2.22Nkc
Evaluation of Wear Performance of Carbon-Based Coatings
No full textThis study aimed to enhance the durability of subsea structures by formulating a composite coating composed of reduced Graphene oxide(rGO) and epoxy resin, and evaluating its wear performance. rGO, a nanomaterial with high mechanical strength, corrosion resistance, and hydrophobicity, was combined with epoxy, offering excellent adhesion, chemical, and wear resistance. Ball-on-Disk tests were conducted on coatings with varying rGO contents (wt%), revealing that the composition containing 0.1 wt% rGO exhibited the best wear resistance. This improvement is attributed to the uniform dispersion of rGO and its mechanical reinforcement effect within the epoxy matrix. The study demonstrates how carbon-based materials' dispersion characteristics and optimal content significantly influence coating performance and
presents a promising high-performance coating technology suitable for harsh marine environments.2
Hair growth promoting effect of Spirulina maxima extract on human dermal papilla cells via modulation of mTOR/Akt and Wnt/β-catenin signaling pathways
No full textHair loss is a common condition influenced by various physiological and environmental factors, including oxidative stress, inflammation, and hormonal dysregulation in hair follicle cells. In this study, we investigated the hair growth promoting effects of Spirulina maxima extract on human dermal papilla cells (HDPCs) and elucidated the underlying mechanisms focusing on mTOR/Akt and Wnt/β-catenin signaling pathways. The results demonstrated that S. maxima extract significantly enhanced the proliferation and alkaline phosphatase (ALP) activity of HDPCs. Moreover, the extract increased both the expression levels of mammalian target of rapamycin (mTOR), β-catenin, Cyclin D1, and proliferating cell nuclear antigen (PCNA), and the phosphorylation levels of protein kinase B (Akt) and glycogen synthase kinase 3β (GSK3β), which are crucial for hair follicle development and regeneration. These findings suggest that S. maxima extract can promote hair growth by modulating mTOR/Akt and Wnt/β-catenin signaling pathways, indicating the potential application of S. maxima as a marine-derived natural resource for hair loss therapeutic agents.22Nkc
Isolation of Natural Products from Marine Invertebrates
No full textMarine invertebrates such as sponges, cnidarians, bryozoans, and tunicates are considered to be prolific sources of novel biologically active natural products. Specimens from these organisms are composed of soft tissues with a high water and inorganic salt content compared to those from terrestrial counterparts. In addition, some of the secondary metabolites from these organisms tend to be more polar than those of terrestrial. These general characteristics have led to the establishment of differentiated protocols for metabolites derived from marine invertebrates. In this chapter, we describe an available protocol for the isolation of secondary metabolites from marine invertebrates, including extraction, fractionation, and purification procedures. While detailed protocols should be adapted to the characteristics of the specific organism being studied, the methods provided here can serve as an initial guide for designing those.Contents
Preface . . .................................................................. v
Contributors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
PART I EXTRACTION AND SEPARATION
1 Natural Products Analysis Through Time: From Past Achievements to Future Prospects . ................................................... 3
Robert Verpoorte and Hye Kyong Kim
2 Optimizing Extraction Solvents for Plant Chemical Analysis Using 1H NMR and Principal Component Analysis . . . . . . . . . . . . . . . . . . . . . . . . 15
Sumin Seo, Sang Beom Han, Karthick Babu Sai Sankar Gupta, and Young Hae Choi
3 High-Resolution Isolation of Natural Products: Efficient Combination of Dryload Injection and HPLC Gradient Transfer. . . . . . . . . . . . . . . . . . . . . . . . . 31
Emerson Ferreira Queiroz, Davy Guillarme, and Jean-Luc Wolfender
4 Standardized HPTLC for Reproducible Chemical Fingerprinting . . . . . . . . . . . . 47
Thi Kieu Tieˆn Do, Ilona Trettin, and Eike Reich
5 Extraction of Anthocyanins with Deep Eutectic Solvents and Chemical Evaluation by High-Performance Liquid Chromatography. . . . . . . . . . . . . . . . . . 63
Yuntao Dai, Robert Verpoorte, and Young Hae Choi
6 Extraction of Essential Oils and Terpene Volatiles from Plants and Identification by GC-MS-Based Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Sandra T. Krause and Maximilian Frey
7 Isolation of Natural Products from Marine Invertebrates . . . . . . . . . . . . . . . . . . . 83
Yeon-Ju Lee and Chinmayee Bawkar
PART II IDENTIFICATION
8 Identification and Profiling of Primary Metabolites Through GC-MS and Associated Data Processing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Minki Shim, Yooseong Jeong, and Dong-Kyu Lee
9 Identification of Flavonoids Using UV-Vis and MS Spectra . . . . . . . . . . . . . . . . . 111
O¨ zlem Erol and Sandra Irmisch
10 Analysis of Salicylate and Phenolic Acids in the Plant by HPLC–Fluorescence Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Natali Rianika Mustafa
11 Isolation and Identification of Coumarins from Citrus latifolia Leaves Using Advanced Chromatographic Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Hocelayne Paulino Fernandes and Luis Francisco Salome´-Abarca
12 Identification of Lignans. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Hye Mi Kim and Chul Young Kim
13 Extraction, Annotation, and Purification of Resin Glycosides from the Morning Glory Family (Convolvulaceae) . . . . . . . . . . . . . . . . . . . . . . . . . 177
Lars H. Kruse, Alexandra A. Bennett, Vishwa J. Baruah, Mohammad Irfan, and Gaurav D. Moghe
14 Extraction, Isolation, and Structural Elucidation of Acylated Triterpene Saponins from Asteraceae Family . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Soohyun Um, Jaeyoun Lee, Mira Oh, and Seung Hyun Kim
15 Analysis and Identification of Polyphenols in Fragaria, Rubus, and Ribes Species by Nontargeted UHPLC-PDA-MS Metabolite Profiling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Simon D. A. Pont and J. William Allwood
16 Identification of Primary Metabolites in 1H NMR-Based Metabolomics of Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Hye Kyong Kim and Young Hae Choi
17 Isolation of Natural Products Using Preparative TLC . . . . . . . . . . . . . . . . . . . . . . 259
Kyu Won Kim, Kyung Ho Lee, Won Sok Ha, Yena Kim, and Young Pyo Jang
18 Sample Preparation of Caenorhabditis elegans for GC-MS-Based Metabolomics in Toxicity Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Jesus G. Arellano Spadaro, Marjolein Wildwater, Henrie Korthout, and Hye Kyong Kim
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Integration of transcriptomics and metabolomics reveals the molecular response to the leachates of hydrothermal ore in the marine copepod Tigriopus koreanus
No full text2
Effect-directed analysis of hazardous organic chemicals released from ship hull hydroblasting effluents and their emission to marine environments
No full textHydroblasting of ship hulls is a significant source of chemical emissions into marine environments, releasing a complex mixture of paint-derived constituents including biocides, pigments, polymeric binders, plasticizers, light stabilizers, and compounds from adhesives and sealants. Although the International Convention on Antifouling Systems highlights the importance of waste management, many countries, including South Korea, have not yet implemented specific regulations addressing hydroblasting effluents. Most existing studies have focused on target biocides, leaving other toxic chemical classes underexplored. This study applied effect-directed analysis to assess hydroblasting effluents using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry. Toxicity screening revealed that the whole effluent exhibited significant toxic effects in zebrafish embryos. Fractionation analysis showed that, of 10 collected fractions, fractions 2 and 3 displayed slight toxicity, while fractions 4–9 showed high toxicity. Non-targeted analysis (NTA) identified 68 compounds in positive electrospray ionization mode and 25 in negative mode in the whole effluent. NTA of individual fractions revealed respective compounds contributing to the observed toxicity. Known toxicants were detected specifically in the toxic fractions. Seven toxicants were confidently identified at Level 1 using authentic standards. Quantitative analysis estimated that the release of these toxicants ranged from 0.16 to 121.83 g per hull cleaning of the one studied ship. When extrapolated globally, annual emissions were estimated to exceed 16 tons. These findings highlight the substantial environmental risks associated with hydroblasting and emphasize the need for regulatory oversight and targeted mitigation strategies to reduce its ecological impact on marine ecosystems.11Nsciescopu