Search Results (154)

This study investigated the spatial and seasonal dynamics of phytoplankton communities in Jaran Bay, inner Hansan Bay, and outer Hansan Bay, with particular emphasis on size structure and pigment-based indicators of productivity and physiological status. Water sampling was conducted during May, August, and October in 2020, 2022, and 2023 and phytoplankton communities were analyzed using size-fractionated chlorophyll a measurements and high-performance liquid chromatography (HPLC) pigment analysis. Chlorophyll a concentrations exhibited pronounced seasonality, with consistently elevated values in August across all bays. Diatoms were predominant throughout the study period; however, their relative contribution declined in outer Hansan Bay during summer, coinciding with increased contributions from cryptophytes and cyanobacteria. Size-fractionated analyses revealed that large-sized phytoplankton (>20 µm) predominantly consisted of diatoms, whereas small-sized phytoplankton (<20 µm) were composed of diatoms and cryptophytes. Comparisons between fluorometric and pigment-based approaches indicated that pigment-based diagnostics overestimated microphytoplankton contributions, attributable to the presence of small-sized diatoms. Pigment indices further revealed that large-sized phytoplankton were characterized by higher photosynthetic carotenoid concentrations and lower photoprotective carotenoid ratios, indicative of enhanced photosynthetic activity and productivity. Overall, these findings highlight the critical role of phytoplankton size structure in regulating productivity and physiological responses in aquaculture-dominated coastal bays. Full article

Streptomyces is a versatile genus widely used in drug production and biotechnological applications. This study aimed to identify and characterize bioactive compounds produced by Streptomyces UP-AC4 and UP-3.2 strains and evaluate their antibacterial and anticancer activities. The strains were identified as Streptomyces californicus and Streptomyces purpurascens via chemotaxonomy, 16S rRNA sequencing, amplified ribosomal DNA restriction analysis, and phylogenetic analysis. Bioactive compounds were extracted using heat treatments at 63 °C for 30 min or 73–110 °C for 10 min. Antibacterial activity against Staphylococcus aureus, Bacillus cereus, and Escherichia coli was assessed by agar disc assay, with MICs of 0.024–0.195 mg/mL and MBCs of 0.098–0.391 mg/mL for the most effective extracts. Anticancer activity against A549, H1299, and Lu99 lung cancer cells was evaluated using the MTT assay, showing IC₅₀ values of 0.23 ± 0.06 to 4.85 ± 0.64 mg/mL, while exhibiting no toxicity to normal fibroblast cells. HPLC analysis indicated that heat-assisted extraction of UP-AC4 at 73 °C for 10 min enriched a dinactin-associated compound as a predominant metabolite with antibiotic and anticancer activities. In conclusion, Streptomyces UP-AC4 and UP-3.2 produce promising low-cost bioactive compounds with strong potential for pharmaceutical and healthcare applications. Full article

Five Salsola species have been studied as sources of bioactive compounds using a comprehensive, untargeted metabolomic and bioactivity assessment. Plant material was extracted using ethyl acetate (EA), water, and methanol (MeOH). S. ruthenica exhibited the highest total phenolic content (46.04 mg GAE/g, MeOH extract) and antioxidant capacity (DPPH: 47.21 mg TE/g; ABTS: 97.40 mg TE/g; CUPRAC: 141.38 mg TE/g; FRAP: 80.30 mg TE/g). Extracts of S. stenoptera and S. ruthenica showed potent cholinesterase inhibition, while S. crassa was notably active against tyrosinase. A total of 265 metabolites were annotated, revealing strong solvent- and species-specific differences in phenolic composition, as confirmed by AMOPLS analysis. Flavanols, anthocyanins, and lignans emerged as the major chemotaxonomic markers, based on PCA, contributing the most to the total variance. Strong correlations were observed between TPC and CUPRAC (r = 0.93) and between flavanols and DPPH (r = 0.70), suggesting functional relevance of these compounds in redox activity, confirming the importance of different classes of phenolic constituents. VIP markers also revealed species- and solvent-specific enrichments of metabolites. Regularized canonical correlation analysis (rCCA) further linked specific metabolites, namely Quercetin 3-O-glucosyl-xyloside and 6″-O-Acetylgenistin, the flavanone sakuranetin, the lignans Secoisolariciresinol, Anhydro-secoisolariciresinol, and Medioresinol, and p-Coumaric acid ethyl ester, with antioxidant functions. These findings underscore the pharmacological potential of Salsola species and highlight the importance of valorizing metabolic diversity in the search for new sources of health-promoting natural compounds. Furthermore, the work shows the need for a tailored solvent selection in bioactivity-guided phytochemical research. Full article

The first comprehensive study about of amber from the Lower Cretaceous of the Lusitanian Basin, in the Estremadura region of western Portugal, is here reported. The amber was recovered as isolated clasts in the Portela da Vila outcrop section, near the small villages of Ramalhal and Ameal, from sedimentary deposits belonging to the Lugar d’Além Formation considered to be of Hauterivian age. The chemical composition of amber clasts was examined in order to infer their botanical source via biomarker analysis. GC–MS and GC×GC–TOFMS showed a strong predominance of abietane-type diterpenoids, including compounds such as amberene, ferruginol (phenolic abietane), kaurane and the derivative of clerodane. The dominance of abietane diterpenoids along with these specific biomarkers is consistent with resin exudation by Araucariaceae/Cheirolepidiaceae conifers, as supported by previous chemotaxonomic studies of Cretaceous amber. Palynological studies of the same sedimentary rock samples highlighted a pollen–spore assemblage characterized by low diversity and number of specimens, and dominated by conifer pollen assigned to the genera Classopollis, Araucariacites and coniferous bisaccate pollen, with relative occurrences of fern spores. The combined geochemical and palynological studies strongly support a source related to conifer plants for the amber here reported. Full article

Isousnic acid (isoUA) has been detected in a few usnic acid (UA)-producing lichens with chemotaxonomic values. IsoUA was first isolated from a specimen belonging to Cladonia arbuscula s.l. (referred to as C. mitis in the publication). However, the isolation and detection of isoUA in this Cladonia species have not been reproduced and confirmed with clear evidence. This study focused on C. arbuscula s.l. collected in Iceland and aimed to (1) identify the lichen specimen using DNA barcoding and (2) investigate whether isoUA is produced using a series of chromatographic methods. The fungal nuclear ribosomal internal transcribed spacer (nrITS) barcode was sequenced, and the specimen was identified as C. arbuscula, following recent circumscription recommendations. Routine metabolite profiling did not detect isoUA, and it could only be identified after vigorous chromatographic purification and concentration steps using flash chromatography and preparative high-performance liquid chromatography. IsoUA was found in trace quantities (~24 µg/g dry weight), which likely explains its absence in routine metabolite profiling. A rapid ultra-high-performance liquid chromatography (UHPLC) method using a pentafluorophenyl column was developed to separate UA and isoUA. Our study highlights the importance of an integrative approach combining DNA barcoding and detailed chromatographic analyses for lichen chemistry research. Full article

A novel bacterial strain, Lysinibacillus sp. JNUCC 51, was isolated from volcanic soil collected at Baengnokdam Crater Lake, Mt. Halla, Jeju Island, Republic of Korea. Phylogenetic, ANI (88.76%), and dDDH (70.4%) analyses indicated that the strain represents a distinct genomic lineage closely related to L. xylanilyticus. The complete genome (5.12 Mb; 37% G+C) encoded 4912 genes, including ten biosynthetic gene clusters (NRPS, β-lactone, RiPP, terpene, and T3PKS types), suggesting strong metabolic versatility. Cells were Gram-positive rods (1.5–3.0 × 0.5–0.7 µm) growing at pH 4.0–9.0 and up to 5% NaCl. Chemotaxonomic profiles revealed iso-C₁₅:₀, iso-C₁₇:₀, and iso-C₁₆:₀ as dominant fatty acids; MK-6/MK-7 as major quinones; and phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine as main polar lipids. Bioactivity-guided fractionation of the culture extract led to the isolation of Diolmycin A2 (phenolic polyketide) and maculosin (diketopiperazine), both exhibiting anti-inflammatory and melanogenesis-inhibitory effects consistent with their PKS/NRPS gene clusters. The culture broth suppressed nitric oxide production in LPS-stimulated RAW 264.7 macrophages and reduced melanin synthesis in α-MSH–induced B16F10 melanocytes. A human patch test (5% extract) confirmed dermatological safety. Overall, Lysinibacillus sp. JNUCC 51 is a volcanic-origin bacterium producing structurally diverse bioactive metabolites with promising postbiotic and cosmeceutical potential, particularly for skin inflammation and pigmentation control. Full article

Reliable taxonomy of biological producers is essential for finding new natural substances. A recent study morphologically re-examined 21 accessed vouchers to confirm multiple reported misidentifications and suggested marine sponges from the genus Rhabdastrella as the only known source of the isomalabaricane triterpenoids. The present study aimed to find isomalabaricane-containing sponges among the samples collected during seven marine expeditions to the Vietnam waters of the South China Sea, accompanied with their identification confirmed using morphological and molecular (18S rRNA and 28S rRNA) analyses. As a result, nine sponges identified as Rhabdastrella globostellata were found to contain isomalabaricanes in their extracts. A chemical investigation of the R. globostellata (PIBOC O63-136) specimen led to the isolation of nine isomalabaricane triterpenoids including the new compound 1, of which the chemical structure was elucidated based on HRESIMS and NMR data. Subsequently, a combination of LC–MS/MS, multivariate statistical analysis, and feature-based molecular networking was applied to detect, annotate, and characterize the isomalabaricane chemical diversity across the nine R. globostellata specimens. As a result, two primary chemotypes containing individual sets of annotated compounds were discovered within the Vietnamese population of this sponge. Moreover, obtained data showed a series of new extremely rare isomalabaricanes in R. globostellata extracts including nitrogen-containing metabolites and glycosides of this structural class. Full article

Jeju Island, a volcanic island located off the southern coast of the Korean Peninsula, harbors highly specialized microbial communities shaped by its unique geological and climatic diversity. In particular, Baengnokdam Crater Lake at the summit of Mt. Halla represents an extreme, oligotrophic volcanic habitat characterized by intense UV radiation, temperature fluctuations, and limited nutrients. From this environment, a novel bacterial strain, Brevibacillus sp. JNUCC 42, was isolated and subjected to comprehensive taxonomic, genomic, and biochemical analyses. The strain is a Gram-positive, aerobic, rod-shaped bacterium that grows optimally at 30 °C and pH 7.0–9.0 with moderate NaCl tolerance (≤3%). Phylogenetic analysis based on 16S rRNA gene sequencing and genome-scale GBDP confirmed its affiliation to the genus Brevibacillus, forming a distinct lineage closely related to B. laterosporus DSM 25^T. Whole-genome sequencing generated a 4.93 Mb circular chromosome with a GC content of 40.7%. Comparative genomic analyses revealed ANI (87.1%) and dDDH (32.8%) values far below the species threshold, supporting its delineation as a novel species. Chemotaxonomic data further distinguished JNUCC 42 by its predominance of anteiso-C₁₅:₀ (37.24%) and iso-C₁₅:₀ (27.78%) fatty acids and the presence of a unique unidentified aminolipid not detected in the type strain. Genome mining identified 21 biosynthetic gene clusters, including NRPS, PKS, and NRPS–PKS hybrids, suggesting its potential to produce structurally diverse secondary metabolites. One of these metabolites, the cyclic dipeptide maculosin [cyclo(L-Pro-L-Tyr)], was purified from the culture extract and structurally characterized by NMR spectroscopy. Functional assays demonstrated that maculosin significantly inhibited α-MSH-induced melanogenesis and intracellular tyrosinase activity in B16F10 melanoma cells without cytotoxicity up to 100 µM. Collectively, these findings indicate that Brevibacillus sp. JNUCC 42 represents a novel species within the genus Brevibacillus and a promising microbial source of bioactive compounds with potential cosmeceutical applications. Full article

Hypoxis hemerocallidea (Hypoxidaece) is thoroughly researched and well documented for its plethora of anecdotal and scientifically backed pharmacological potentials. Its anecdotal uses and pharmacological activities are attributed to its extract’s inherent bioactive compounds like hypoxoside, rooperol, and β-sitosterol. This study aimed at conducting a targeted and holistic phytochemical profiling of variations in Hypoxis hemerocallidea (H. hemerocallidea) and related species. The chemotaxonomic classifications of H. hemerocallidea and seven other related species were also carried out to avert the possibility of over harvesting H. hemerocallidea and the encouragement of species inter-change. The plant extracts were analysed with reverse phase ultra-pure liquid chromatography quadrupole time-of-flight mass spectrometry and gas chromatography, as well as high-performance thin-layer chromatography. The generated chromatographic data were made compatible for chemometric computation using Principal Component Analysis (PCA) and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) models. The results obtained unveil orcinol glycoside, curculigoside C, hypoxoside, dehydroxyhypoxoside, bisdehydroxy hypoxoside, hemerocalloside, galpinoside, cholchicoside, geraniol glycoside, β-sitosterol, oleic acid, and 2-hydroxyethyl linoleate as target phytochemicals that define the profiles of the Hypoxis species. In addition, three distinct chemotypes defined by hemerocalloside, galpinoside, and colchicoside, respectively, were observed, as well as holistic variations in all secondary metabolites. Due to similarities in the phytochemical constituents of selected species, species inter-change seems imminent if further research confirms the findings of this study. Full article

A novel species of the genus Methylocystis is proposed based on polyphasic evidence from strain SC2^T, isolated from the heavily polluted Saale River near Wichmar, Germany. Digital DNA–DNA hybridization and phylogenomic analyses demonstrate that strain SC2^T represents a distinct species within the genus, clearly separated from its closest relatives, namely Methylocystis suflitae NLS-7^T, Methylocystis rosea SV97^T, Methylocystis silviterrae FS^T, and Methylocystis hirsuta CSC1^T. As is typical of the family Methylocystaceae, cells possess intracytoplasmic membranes arranged parallel to the cytoplasmic membrane, and the dominant fatty acids are C18:1ω8c and C18:1ω7c. The strain grows aerobically on methane as the primary carbon and energy source and expresses both low- and high-affinity particulate methane monooxygenase (pMMO), but lacks the soluble form. The species epithet reflects the strain’s ability to utilize hydrogen as an alternative energy source. A further feature is its use of asparagine as an osmoprotectant, enhancing salt tolerance. Genomic analysis reveals complete pathways for nitrogen fixation, denitrification, and hydrogen oxidation. These genetic and physiological characteristics support the designation of a novel species, for which the name Methylocystis hydrogenophila sp. nov. is proposed. The type strain is SC2^T (=DSM 114506 = NCIMB 15437). Full article

Gongora is a neotropical epiphytic orchid found from Mexico to South America, with 11 species recorded in Brazil. Little is known about the aromas produced by the flowers of these orchid species. This study aimed to identify the volatile constituents of the flowers of Gongora histrionica (1), G. jauariensis (1), G. longiracemosa (2), G. minax (1), and G. pleiochroma (2), all of which are found in the Amazon. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile constituents of Gongora. Additionally, multivariate statistical analysis was employed to evaluate the variability of volatile constituents in their floral aromas. The principal constituents (>25%) of Gongora specimens were (Z)-α-bisabolene, terpinen-4-ol, cis-β-elemenone, (E,E)-geranyl linalool, β-bisabolene, (E,E)-α-farnesene, and 1,8-cineole. Based on the identified compounds, the multivariate statistical analysis revealed seven distinct groups for the Gongora volatile concentrates, indicating a significant variability between the studied species. These results contribute to a better understanding of the genus Gongora chemotaxonomy analysis. Full article

Metabolite fingerprint profiling is a robust tool for verifying suppliers of authentic botanical ingredients. While comparative studies exist, few apply identical conditions across multiple species; this study utilized a cross-species comparison to identify versatile solvents despite biochemical variability. Multiple solvents were used for sample extraction prior to analysis by proton NMR and liquid chromatography–mass spectrometry (LC-MS) for multiple botanicals including Camellia sinensis, Cannabis sativa, Myrciaria dubia, Sambucus nigra, Zingiber officinale, Curcuma longa, Silybum marianum, Vaccinium macrocarpon, and Prunus cerasus. Comparisons were normalized by total intensity; deuterated methanol aids NMR lock but is not required for LC-MS. Hierarchical clustering analysis (HCA) evaluated solvent efficacy. Methanol–deuterium oxide (1:1) was the most effective extraction method, yielding 155 NMR spectral metabolite variables for Camellia sinensis, while methanol (90% CH₃OH + 10% CD₃OD) produced 198 for Cannabis sativa and 167 for Myrciaria dubia, with 11, 9, and 28 assigned metabolites, respectively. LC-MS detected 121 metabolites in Myrciaria dubia in methanol as the most effective extraction method. Methanol (10% deuterated) is the most effective extraction method for comprehensive metabolite fingerprinting using NMR and LC-MS protocols because it provides the broadest metabolite coverage. This study advances fit-for-purpose methods to qualify suppliers of botanical ingredients in food and NHP quality control programs. Full article

Plant genetics and chemotaxonomic analysis are considered key parameters in understanding evolution, plant diversity and adaptation. Korean Peninsula has a unique biogeographical landscape that supports various aromatic plant species, each with considerable ecological, ethnobotanical, and pharmacological significance. This review aims to provide a comprehensive overview of the chemotaxonomic traits, biological activities, phylogenetic relationships and potential applications of Korean aromatic plants, highlighting their significance in more accurate identification. Chemotaxonomic investigations employing techniques such as gas chromatography mass spectrometry, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy have enabled the identification of essential oils and specialized metabolites that serve as valuable taxonomic and diagnostic markers. These chemical traits play essential roles in species delimitation and in clarifying interspecific variation. The biological activities of selected taxa are reviewed, with emphasis on antimicrobial, antioxidant, anti-inflammatory, and cytotoxic effects, supported by bioassay-guided fractionation and compound isolation. In parallel, recent advances in phylogenetic reconstruction employing DNA barcoding, internal transcribed spacer regions, and chloroplast genes such as rbcL and matK are examined for their role in clarifying taxonomic uncertainties and inferring evolutionary lineages. Overall, the search period was from year 2001 to 2025 and total of 268 records were included in the study. By integrating phytochemical profiling, pharmacological evidence, and molecular systematics, this review highlights the multifaceted significance of Korean endemic aromatic plants. The conclusion highlights the importance of multidisciplinary approaches including metabolomics and phylogenomics in advancing our understanding of species diversity, evolutionary adaptation, and potential applications. Future research directions are proposed to support conservation efforts. Full article

This review highlights the critical role of chemotaxonomy in the identification, authentication, and discovery of bioactive compounds in medicinal plants. By analyzing secondary metabolites using techniques like UV spectroscopy, FTIR, HPLC, GC-MS, NMR, LC-MS-Qtof, and MALDI-TOF MS, chemotaxonomy ensures accurate plant identification, supporting the safe and effective use of plants in herbal medicine. Key secondary metabolites used in chemotaxonomic identification include alkaloids, flavonoids, terpenoids, phenolics, tannins, and plant peptides. Chemotaxonomy also facilitates the discovery of novel compounds with therapeutic potential, contributing to drug development. The integration of chemotaxonomy with genomics and proteomics allows a deeper understanding of plant biosynthesis and the mechanisms behind bioactive compound production. However, challenges due to variability in metabolite profiles and the lack of standardized methods remain, and future research should focus on developing global databases, improving standardization, and incorporating artificial intelligence and machine learning to enhance plant identification and bioactive compound discovery. The integration of chemotaxonomy with personalized medicine offers the potential to tailor plant-based therapies to individual genetic profiles, advancing targeted treatments. This review underscores chemotaxonomy’s importance in bridging traditional knowledge and modern science, offering sustainable solutions for medicinal plant use and drug development. Full article

Chemotaxonomic profiling based on secondary metabolites offers a reliable approach for identifying and authenticating medicinal plants, addressing limitations associated with traditional morphological and genetic methods. Recent advances in microfluidics and nanoengineered technologies—including lab-on-a-chip systems as well as nano-enabled optical and electrochemical sensors—enable the rapid, accurate, and portable detection of key metabolites, such as alkaloids, flavonoids, terpenoids, and phenolics. Integrating artificial intelligence and machine learning techniques further enhances the analytical capabilities of these technologies, enabling automated, precise plant identification in field-based applications. Therefore, this review aims to highlight the potential applications of micro- and nanoengineered devices in herbal medicine markets, medicinal plant authentication, and biodiversity conservation. We discuss strategies to address current challenges, such as biocompatibility and material toxicity, technical limitations in device miniaturization, and regulatory and standardization requirements. Furthermore, we outline future trends and innovations necessary to fully realize the transformative potential of these technologies in real-world chemotaxonomic applications. Full article