Dentatacid A: An Unprecedented 2, 3-Seco-arbor-2, 3-dioic Triterpenoid from the Invasive Plant Euphorbia dentata, with Cytotoxicity Effect on Colon Cancer.

Euphorbia dentata Michx. is an invasive plant species in China, known for its toxicity and potential to reduce crop yields, posing numerous threats. To gain a deeper understanding of this invasive plant, phytochemical methods were employed to isolate 13 terpenoids (1-11, 19, 20) and 7 sterols (12-18) from the ethanol extract of E. dentata, identifying one new compound and 19 known compounds. Within spectroscopic methods such as NMR, HR-ESI-MS, and ECD, the structures and absolute configurations of these compounds were established. Among them, dentatacid A (11) possesses an unprecedented 2, 3-seco-arbor-2, 3-dioic skeleton within the potential biosynthetic pathway proposed. Dentatacid A also exhibited excellent anti-proliferative activity against the HT-29 (human colorectal adenocarcinoma) cell line, with an IC50 value of 2.64 ± 0.78 µM, which was further confirmed through network pharmacology and molecular docking. This study significantly expands the chemical diversity of E. dentata and offers new insights into the resource utilization and management of this invasive plant from the perspective of natural product discovery.

Quercus dentata Thunb. leaves extract inhibits CaOx crystallization and ameliorates ethylene glycol-induced CaOx kidney stones via the OPN/CD44 and NLRP3 pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Quercus dentata Thunb. (QD), a member of the Fagaceae family and genus Quercus, with distributions in China, Japan, Korea, and other regions. As recorded in the Ben Cao Gang Mu (Compendium of Materia Medica) and other classical Chinese medical texts, QD has been traditionally employed in Traditional Chinese Medicine (TCM) for their hemostatic and diuretic effects and has been used to treat urinary stones (Lin Zheng). It is also the main ingredient of the Mishitong capsule (MST), a Chinese patent drug, used for kidney stones and ureteral stones. Nonetheless, the specific active ingredients and the mechanisms of QD in treating kidney stones remain to be elucidated, which is crucial for advancing the scientific understanding and clinical application of this traditional medicine. AIM OF STUDY: This study aimed to identify the active constituents of QD water extract (QDWE), explore its inhibitory effects on kidney stones through in vitro and in vivo studies, and elucidate the underlying mechanisms of the OPN/CD44 axis and the NLRP3 signaling pathway to provide a full understanding of its potential as a novel treatment approach against kidney stones. MATERIALS AND METHODS: The micromolecular components in the supernatant of QDWE (QDS) were analyzed by UPLC-Q-Exactive-Orbitrap-MS and the monosaccharide composition of the macromolecular polysaccharide components in the crude polysaccharide (QDP) was determined by pre-column derivatization in HPLC. The effects of QDWE, QDS and QDP on the shape, size, and structure of calcium oxalate (CaOx) crystals in vitro were explored by XRD, FTIR and SEM. The effects of QDWE, QDS and QDP on CaOx kidney stones in SD rats induced by ethylene glycol and VD3 were compared in vivo. Furthermore, the underlying mechanisms of OPN/CD44 and NLRP3 pathways were investigated by Western blot analysis. RESULTS: There were 32 compounds identified in QDS. The monosaccharide composition ratio of QDP was Man: L-Rha: D-GlcA: D-GalA: D-Glc: D-Gal: L-Ara = 1.01: 22.52: 8.27: 38.61: 3.43: 17.80: 6.38, indicating a mixture of pectin-type acidic heteropolysaccharides. QDP had a more significant inhibitory effect on CaOx crystals in vitro than QDWE, which can inhibit the formation of CaOx monohydrate crystals (COM) and convert them into thermodynamically unstable CaOx dihydrate (COD) crystals. The high dose of QDWE exhibited significant in vivo efficacy (P < 0.05), including anti-calculus, diuretic effects, and kidney protection, marked by decreased calcification and stone formation, alongside improved kidney vitality. Furthermore, the protective effects of QDWE were demonstrated to be associated with the OPN/CD44 and NLRP3 pathways. CONCLUSION: The studies identified and analyzed the active constituents of QDWE. Among these, QDP significantly inhibited CaOx crystal generation in vitro and could be a potential component for the treatment of urinary stones in QDWE. Moreover, the results indicated that QDWE had a remarkable therapeutic effect on CaOx stones by modulating the OPN/CD44 axis to affect stone formation and the NLRP3 signaling pathway to mediate inflammation, providing an experimental basis for the mechanism of anti-urinary stone and deep development of QD.

Formulation of a Three-Component Essential Oil Mixture from Lavandula dentata, Rosmarinus officinalis, and Myrtus communis for Improved Antioxidant Activity.

The optimization of existing natural antioxidants that are highly effective is crucial for advancements in medicine and the food industry. Due to growing concerns regarding the safety of synthetic antioxidants, researchers are increasingly focusing on natural sources, particularly essential oils (EOs). Combining EOs might enhance antioxidant activity due to increased chemical diversity. This study investigates, for the first time, the antioxidant properties of EOs from Lavandula dentata, Rosmarinus officinalis, and Myrtus communis, both individually and in combination, using the augmented-simplex design methodology. The in vitro evaluation of the antioxidant activity was performed using DPPH and ABTS radical scavenging assays. Chromatography gas-mass spectrometry (CG-MS) revealed that 1,8-cineol (37.27%) and pinocarveol (12.67%) are the primary components of L. dentata; verbenone (16.90%), camphor (15.00%), and camphene (11.03%) are predominant in R. officinalis; while cineol (43.32%) is the main component of M. communis. The EOs showed varying scavenging activities against ABTS and DPPH radicals, with DPPH assay values ranging from 194.10 ± 3.01 to 541.19 ± 3.72 µg/mL and ABTS assay values ranging from 134.07 ± 1.70 to 663.42 ± 2.99 µg/mL. These activities were enhanced when the EOs were combined. The optimal antioxidant blend for DPPHIC50 consisted of 20% L. dentata, 50% R. officinalis, and 30% M. communis. For the highest ABTS radical scavenging activity, the best combination was 18% L. dentata, 43% R. officinalis, and 40% M. communis. These results highlight the potential of EO combinations as new natural formulations for use in cosmeceutical, food, and pharmaceutical sectors.

Genome-wide identification of metal tolerance protein genes in Quercus dentata and their roles in response to various heavy metal stresses.

Metal tolerance protein (MTP) is a cation transporter that plays an important role in tolerance to heavy metal stress. However, thus far, there has been no genome-wide investigation of the MTP gene family in Quercus plants. Quercus dentata is one of the main constructive species of forest in northern China. It has strong tolerance to a variety of heavy metal stresses. In this study, 25 MTPs were identified from the Q. dentata genome and classified into three subfamilies and seven groups according to their sequence characteristics and phylogenetic relationships. Both tandem and segmental duplication events contributed to the expansion of the QdMTP gene family. Interestingly, all 10 tandem duplication events contributed to the expansion of the Mn-CDF subfamily. The expression of Mn-CDF subfamily members in different organs and tissues of Q. dentata was different, and they responded differently to manganese, iron, zinc and cadmium stress treatments. QdMTP10.7, a member of the Mn-CDF subfamily, enhanced yeast growth under manganese, zinc and iron stresses. The subcellular localization in tobacco leaf epidermis cells showed that QdMTP10.7 was located in vacuoles. These data generated from this study provide an important foundation to elucidate the biological roles of QdMTP genes related to heavy metal tolerance in Q. dentata.

Analysis of the Fungal Community Composition in Endemic Orchids with Terrestrial Habitat in Subtropical Regions.

Habenaria and Liparis are well-known orchid genera that grow in terrestrial habitats in the tropics, subtropics or temperate zones. Three species have been found in subtropical regions of China, inhabiting terrestrial to epiphytic habitats. This study focuses on three species, H. dentata (distributed in Asia), H. yachangensis, and L. gigantea. For H. yachangensis and L. gigantea, there is no information about the mycorrhizal community in these species. This study aims to conduct the fungal community screening of Chinese ground orchids from subtropical regions. We performed a comparative analysis of the fungal community among H. dentata, H. yachangensis, and L. gigantea, determining their ITS regions using NGS paired-end sequences. The results clarified the diversity and the predominance of fungal genera. Ascomycota was abundant compared to Basidiomycota or other fungi groups in all communities, with a high dominance in all populations, especially for L. gigantea. At different root spatial locations, the fungal community diversity and richness were higher in the soil than in the rhizosphere or inner root. However, the results suggest that L. gigantea has a different fungal community compared to Habenaria species. In this order, the subtropical terrestrial orchids have a different fungal network compared to the northern terrestrial orchids. Also, there is a high probability of co-existence and co-evolution of endophytic fungi in these terrestrial orchids, indicating the potential role of host plants in selecting an endophytic fungal community. Furthermore, our results highlight the need to elucidate the microbe interactions of these unique orchids for long-term purposes, such as isolating indigenous fungi for suitable inoculants for further orchid propagation, restoration, and conservation.

Phytochemical analysis and investigation of analgesic, anti-inflammatory, and antispasmodic activities of hydroethanolic extracts of Alternanthera dentata, Ocimum carnosum, and Plectranthus barbatus, three species with vernacular names derived from analgesic drugs.

ETHNOPHARMACOLOGICAL RELEVANCE: Plant vernacular names can provide clues about the popular use of a species in different regions and are valuable sources of information about the culture or vocabulary of a population. Several medicinal plants in Brazil have received names of medicines and brand-name products. AIM OF THE STUDY: The present work aimed to evaluate the chemical composition and pharmacological activity in the central nervous system of three species known popularly by brand names of analgesic, anti-inflammatory, antispasmodic, and digestive drugs. MATERIALS AND METHODS: Hydroethanolic extracts of Alternanthera dentata (AD), Ocimum carnosum (OC), and Plectranthus barbatus (PB) aerial parts were submitted to phytochemical analysis by HPLC-PAD-ESI-MS/MS and evaluated in animal models at doses of 500 and 1000 mg/kg. Mice were tested on hot plate, acetic acid-induced writing, formalin-induced licking, and intestinal transit tests. Aspirin and morphine were employed as standard drugs. RESULTS: The three extracts did not change the mice's response on the hot plate. Hydroethanolic extracts of AD and PB reduced the number of writhes and licking time, while OC was only effective on the licking test at dose of 1000 mg/kg. In addition, AD and OC reduced intestinal transit, while PB increased gut motility. CONCLUSIONS: Pharmacological tests supported some popular uses, suggesting peripheral antinociceptive and anti-inflammatory effects, while the phytochemical analysis showed the presence of several flavonoids in the three hydroethanolic extracts and steroids in PB, with some barbatusterol derivatives described for the first time in the species.

Effects of pan- and air fryer-roasting on volatile and umami compounds and antioxidant activity of dried laver (Porphyra dentata).

This study aimed to investigate the impact of pan- and air fryer-roasting on the volatiles, umami compounds, antioxidant activity, and sensory attributes of dried laver (Porphyra dentata). To assess the influence of time and temperature, pan-roasting was conducted at temperatures of 250, 300, and 350 °C for 5, 10, and 15 s, respectively. For air fryer-roasting, dried laver was roasted at 160, 170, and 180 °C for 2, 4, and 6 min, respectively. In both roasting methods, the levels of 1,5-octadien-3-ol and 1-octen-3-ol significantly decreased (p < 0.05) with increased time and temperature. The Equivalent Umami Concentration ranged from 94.89 to 518.09 g MSG/100 g. The antioxidant activity significantly increased (p < 0.05) with higher roasting temperatures and longer durations, whereas pigment content significantly decreased. The browning index increased by 64% and 43% for the pan and air frying methods, respectively. The samples pan-roasted at 300 °C for 15 s obtained the highest sensory scores.

Utilization and transformation of Chrysotila dentata-derived dissolved organic matter by phycosphere bacteria Marinobacter hydrocarbonoclasticus and Bacillus firmus.

The dissolved organic matter (DOM) released from the cocoolithophores (Chrysotila dentata) was studied in laboratory experiments after co-culturing C. dentata with bacteria. Marinobacter hydrocarbonoclasticus (CA6)-γ-Proteobacteria and Bacillus firmus (CF2) were used to investigate the utilization and processing of the DOM derived from C. dentata, utilizing fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (EEM-PARAFAC), while measuring algal abundance and photosynthetic parameters. The experimental groups consisted of axenic C. dentata groups, filter cultured with bacteria (CA6 or CF2) groups, C. dentata co-cultured with bacteria (CA6 or CF2) groups and axenic bacteria (CA6 or CF2) groups. We then evaluated the processing of DOM by determining four fluorescence indices. The number of C. dentata cells and the photosynthetic capacity of microalgae were enhanced by CA6 and CF2. The main known fluorophores, including humic-like components and protein-like components, were present in all sample. The protein-like component of algal-bacterial co-cultures was effectively utilized by CA6 and CF2. The humic-like components increased at the end of the culture time for all cultures. Meanwhile, the average fluorescence intensity of protein-like in CA6 co-culture with algae was lower than that in CF2 co-culture with algae over time. On the other hand, the average fluorescence intensity of humic-like in CA6 was higher than CF2. However, the total change in fluorescence in humic-like and protein-like of axenic CF2 cultures was lower than that of CA6. Hence, the ability of CA6 to transform microalgal-derived DOM was superior to that of CF2, and CF2's ability to consume bacterial-derived DOM was superior to that of CA6.

Norsesquiterpenes from the Latex of Euphorbia dentata and Their Chemical Defense Mechanisms against Helicoverpa armigera.

Euphorbia dentata (Euphorbiaceae), an invasive weed, is rarely eaten by herbivorous insects and could secrete a large amount of white latex, causing a serious threat to local natural vegetation, agricultural production and human health. In order to prevent this plant from causing more negative effects on humans, it is necessary to understand and utilize the chemical relationships between the latex of E. dentata and herbivorous insects. In this study, three new norsesquiterpenes (1-3), together with seven known analogues (4-10), were isolated and identified from the latex of E. dentata. All norsesquiterpenes (1-10) showed antifeedant and growth-inhibitory effects on H. armigera with varying levels, especially compounds 1 and 2. In addition, the action mechanisms of active compounds (1-3) were revealed by detoxifying enzyme (AchE, CarE, GST and MFO) activities and corresponding molecular docking analyses. Our findings provide a new idea for the development and utilization of the latex of E. dentata, as well as a potential application of norsesquiterpenes in botanical insecticides.

Development of Essential Oil-Loaded Polymeric Nanocapsules as Skin Delivery Systems: Biophysical Parameters and Dermatokinetics Ex Vivo Evaluation.

Essential oils (EOs) are natural antioxidant alternatives that reduce skin damage. However, EOs are highly volatile; therefore, their nanoencapsulation represents a feasible alternative to increase their stability and favor their residence time on the skin to guarantee their effect. In this study, EOs of Rosmarinus officinalis and Lavandula dentata were nanoencapsulated and evaluated as skin delivery systems with potential antioxidant activity. The EOs were characterized and incorporated into polymeric nanocapsules (NC-EOs) using nanoprecipitation. The antioxidant activity was evaluated using the ferric thiocyanate method. The ex vivo effects on pig skin were evaluated based on biophysical parameters using bioengineering techniques. An ex vivo dermatokinetic evaluation on pig skin was performed using modified Franz cells and the tape-stripping technique. The results showed that the EOs had good antioxidant activity (>65%), which was maintained after nanoencapsulation and purification. The nanoencapsulation of the EOs favored its deposition in the stratum corneum compared to free EOs; the highest deposition rate was obtained for 1,8-cineole, a major component of L. dentata, at 1 h contact time, compared to R. officinalis with a major deposition of the camphor component. In conclusion, NC-EOs can be used as an alternative antioxidant for skin care.

The Genetic Diversity and Genetic Structure of the Germplasm Resources of the Medicinal Orchid Plant Habenaria dentata.

Habenaria dentata has medicinal and ornamental value, but the number of wild populations is decreasing dramatically. Thus, conducting research on its genetic diversity and structure is necessary to provide a basis for its conservation. This study aimed to explore the genetic diversity of the wild plant H. dentata and protect and optimize its wild resources. The genetic diversity of 133 samples from six wild populations of H. dentata was analyzed using Inter Simple Sequence Repeat molecular markers to provide a scientific basis for the screening of improved germplasm resources. The results showed that the average number of alleles was 1.765, the average number of effective alleles was 1.424, the average Nei's gene diversity index was 0.252, the average Shannon diversity index was 0.381, and the average percentage of polymorphic loci was 76.499%. The variation within the populations was 77.34%, and the variation between the populations was 22.66%. The gene flow was 1.705, which was greater than 1. The results of the cluster analysis showed that the six populations were mainly divided into four clusters and were not classified according to their geographical location. There was no significant correlation between the geographical location and genetic distance between the populations (r = 0.557, p > 0.05). The genetic diversity of H. dentata is high. Among the six wild populations, the genetic diversity of the Mulun population was the highest and this population can be used as a key protection unit. The study on the genetic diversity of H. dentata can not only reveal the reasons for the decrease in the number of individuals in the population to a certain extent, and put forward the protection strategy, but also provide a scientific basis for the breeding of excellent seed resources.

Phytochemical analysis, antibacterial and antifungal effect of Lavandula dentata L. essential oil and methanol extract.

The aim of this study was to analyse the essential oil of Lavandula dentata from Algeria and to test the antioxidant and antimicrobial properties of this plant. The essential oil (EO) (57 constituents) included mainly α-pinene, ß-pinene, nopinone, linalool, cryptone, and limonene. The plant polyphenolic contents and the antioxidant activity were determined. The antimicrobial effect of the EO and the methanolic extract (ME) was assessed against referenced and clinical bacterial strains, and also foodborne fungal isolates. The EO minimal inhibitory concentration (MIC) values varied from 0.25 to 4 mg/mL and minimal bactericidal concentrations (MBCs) were less than 8 mg/mL except for S. aureus, clinical Klebsiella, S. epidermidis, and B. subtilis. The mould strains were significantly inhibited by the EO (87.50% to 88.33%). The MIC values were 3.60-15.62 mg/mL and 0.5-4 mg/mL for ME and EO, respectively. The minimal fungicidal concentration (MFC) values ranged from 31 to 125 mg/mL and from 2 to 8 mg/mL for ME and EO, respectively.

First report of Botryosphaeria dothidea causing brown leaf spot on Daimyo oak, Quercus dentata in China.

Quercus dentata is a deciduous oak species widely distributed in northern China, with short petioles and dense grayish brown stellate tomentose on the abaxial surface (Lyu et al., 2018). Q. dentata is cold-tolerant (Du et al., 2022), and its broad leaves are used for tussah silkworm rearing, traditional Chinese medicine, kashiwa mochi in Japan, and Manchu delicacy in Northeast China (Wang et al., 2023). In June 2020, a single Q. dentata plant with brown leaf spots was observed in the Oak Germplasm Resources Nursery (N41°82', E123°56') in SYAU, Shenyang, China. From 2021 through 2022, other two nearby Q. dentata plants (six trees in all) became diseased with similar brown spots on their leaves. The small brown lesions with subcircular or irregular shape gradually expanded, and then the entire leaf turned brown. Under magnification, the diseased leaves contain many conidia. To identify the pathogen, diseased tissues were surface sterilized in 2% sodium hypochlorite for 1 min, and washed in sterile distilled water. Lesion margins were plated onto potato dextrose agar and incubated at 28°C in darkness. The aerial mycelium changed color, from white to dark gray, and dark olive green pigmentation was observed on the medium reverse side after 5 days of incubation. The emerging fungal isolates were repurified by the single-spore method. The mean length and width of spores were 20.32 ± 1.90 × 5.2 ± 0.52 µm (n=50). These morphological characteristics resembled the description of Botryosphaeria dothidea (Slippers et al., 2014). For molecular identification, internal transcribed spacer (ITS) region, translation elongation factor1 alpha (tef1-α), and beta-tubulin (tub) were amplified. These new sequences GenBank accession nos. are OQ383627.1, OQ387861.1 and OQ387862.1. Blastn searches showed 100% homology with ITS sequence of B. dothidea strain P31B (KF293892.1) and 98 to 99% similarity with tef and tub sequences of B. dothidea isolate ZJXC2 (KP183219.1) and B. dothidea isolate SHSJ2-1 (KP183133.1). The sequences were also concatenated for phylogenetic analysis (maximum likelihood). Result support isolate SY1 in the same clade as B. dothidea. Based on the multi-gene phylogeny and morphology, the isolated fungus associated with brown leaf spot on Q. dentata was identified as B. dothidea. Pathogenicity tests were performed on five-year-old potted plants. Conidial suspensions (106 conidial/mL) were applied on punctured leaves using a sterile needle and non-punctured leaves. Non-inoculated plants spayed with sterile water served as control. Plants were placed in a growth chamber at 25°C on a 12h fluorescent light/dark regime. Symptoms similar to those from natural infections were observed after 7 to 9 days (non-punctured also infected). No symptoms were found on non-inoculated plants. The pathogenicity test was repeated three times. Fungi re-isolated from inoculated leaves were comfirmed as B. dothidea on the basis of morphological and molecular characterization as described above, fulfilling Koch's postulates. B. dothidea was previously reported as a pathogen causing branch diebacks and twig dieback on sycamore, red oak (Quercus rubra), and English oak (Quercus robur) in Italy (Turco et al., 2006). It has also been reported to cause leaf spot on Celtis sinensis, Camellia oleifera and Kadsura coccinea in China (Wang et al., 2021; Hao et al., 2022; Su et al., 2021). To our knowledge, this is the first report of B. dothidea inducing leaf spot on Q. dentata in China.

Identification of Unstable Ellagitannin Metabolites in the Leaves of Quercus dentata by Chemical Derivatization.

The identification of unstable metabolites of ellagitannins having ortho-quinone structures or reactive carbonyl groups is important to clarify the biosynthesis and degradation of ellagitannins. Our previous studies on the degradation of vescalagin, a major ellagitannin of oak young leaves, suggested that the initial step of the degradation is regioselective oxidation to generate a putative quinone intermediate. However, this intermediate has not been identified yet. In this study, young leaves of Quercus dentata were extracted with 80% acetonitrile containing 1,2-phenylenediamine to trap unstable ortho-quinone metabolites, and subsequent chromatographic separation afforded a phenazine derivative of the elusive quinone intermediate of vescalagin. In addition, phenylenediamine adducts of liquidambin and dehydroascorbic acid were obtained, which is significant because liquidambin is a possible biogenetic precursor of C-glycosidic ellagitannins and ascorbic acid participates in the production of another C-glycosidic ellagitannin in matured oak leaves.

Phytochemical composition, cytotoxicity, antioxidant and antimicrobial responses of Lavandula dentata L. grown under different levels of heavy metals stress condition.

In order to know if the heavy metals stress condition is boon or bane for the plants growth, Lavandula dentata species was planted in pots under different levels of heavy metals stress condition and the phytochemical composition, cytotoxicity, antioxidant and antimicrobial responses of their leaf ethanolic extracts toward this stress condition were investigated compared to the control samples. Our findings showed significant differences in heavy metals bioaccumulation, photosynthetic pigments and total phenolic/flavonoids contents among L. dentata leafs ethanolic extracts, grown under different levels of heavy metals stress condition. The L. dentata leafs extracts, grown under Zn and Cu stress condition, showed the highest antioxidant and antimicrobial activities than those grown under Cd and Pb stress condition. Comparatively, the L. dentata leafs extracts, grown under Zn stress condition, showed higher antioxidant activity, and those, grown under Cu stress condition, showed higher antimicrobial activity. The highest cytotoxicity was showed by L. dentata leaf extracts, grown under Cd and Pb stress condition, which lead to conclude that these extracts could be served as a novel scaffold in search for new drugs against cancer. In conclusion, the highlighted variability reflects the high impact of heavy metals stress condition on phytochemical composition and consequently on the biological activities of medicinal plants. Such impact led to conclude that we should select medicinal plants extracts to be investigated carefully depending on this stress condition, in order to isolate the bioactive components or to have the best quality of extracts in terms of biological activities.

Essential Oil Composition and Traditional Uses of Salvia dentata, a Poorly Known Medicinal Plant from Namaqualand, South Africa.

South Africa has a rich history of medicinal plant species and their documented uses as traditional medicines, and is also home to three well-known, blue-flowered sage species of ethnobotanical importance. The Namaqualand bloublomsalie (Salvia dentata) has so far remained unstudied and apparently overlooked. Our study is the first to report on the essential oil chemistry of this medicinally relevant species and provide a comparison with the other two (well-studied) closely related Cape bloublomsalies (Salvia africana and S. chamelaeagnea). The data, generated from three geographically isolated populations comprised of 13 individual plants of S. dentata, revealed diagnostically high levels of camphor (14.37%), α-pinene (11.43%), camphene (10.18%), 1,8-cineole (eucalyptol) (9.42%) and bornyl acetate (8.56%) which provide a distinct chemical profile from the other two species.

The complete mitochondrial genome of Neoporphyra dentata (Bangiales, Rhodophyta).

Neoporphyra dentata (Kjellman) L.-E. Yang & J. Brodie, 2020 is an economically valuable species in seaweed aquaculture in the southwest coastal regions of Korea. Here, we report the complete mitogenome information of N. dentata using Illumina Miseq platform permitted assembly of a circular mitochondrial genome of 26,807 bp from N. dentata consisting of 29.9% GC contents, 9 protein coding genes (PCGs), 2 ribosomal RNA genes (12S rRNA and 16S rRNA), 23 transfer RNA (tRNA) genes, and a non-coding region. The overall nucleotide composition was A: 38%, T: 32%, C: 14.7%, and G: 15.2%. The mitochondrial genome of N. dentata contributes to revealing the phylogenetic relationships among species of the Bangiaceae family.

Bioinformatic Prediction and Characterization of Proteins in Porphyra dentata by Shotgun Proteomics.

Porphyra dentata is an edible red seaweed with high nutritional value. It is widely cultivated and consumed in East Asia and has vast economic benefits. Studies have found that P. dentata is rich in bioactive substances and is a potential natural resource. In this study, label-free shotgun proteomics was first applied to identify and characterize different harvest proteins in P. dentata. A total of 13,046 different peptides were identified and 419 co-expression target proteins were characterized. Bioinformatics was used to study protein characteristics, functional expression, and interaction of two important functional annotations, amino acid, and carbohydrate metabolism. Potential bioactive peptides, protein structure, and potential ligand conformations were predicted, and the results suggest that bioactive peptides may be utilized as high-quality active fermentation substances and potential targets for drug production. Our research integrated the global protein database, the first time bioinformatic analysis of the P. dentata proteome during different harvest periods, improves the information database construction and provides a framework for future research based on a comprehensive understanding.

Identification of potential plant species hyperaccumulating light rare earth elements (LREE) in a mining area in Minas Gerais, Brazil.

Phytoextraction of rare earth elements (REE) from contaminated soils has gained importance during the last few decades. The Poços de Caldas municipality in Brazil is known for its mineral richness, including large reserves of REE. In this study, we report light REE (La, Ce, Sm, Pr, and Nd) in soils and plants collected in an area. Composite soil samples and plant individuals were collected, and total concentrations of LREE in soils were determined by wavelength dispersive X-ray fluorescence (WDXRF). The plant available LREE concentrations in soils were estimated upon the acetic acid method (F1 fractions) of the stepwise sequential extraction procedure, together with plant content that was analysed by inductively coupled plasma mass spectrometry (ICP-MS). The total sum concentrations of tested LREE in soils varied from 5.6 up to 37.9 g kg-1, the bioavailable fraction was ca. 1%, and a linear relationship was found between them. The only exception was Sm, whose availability was lesser and did not show a linear relationship. The concentration of LREE in non-accumulator plants varied from 1.3-950 mg kg-1 for Ce, La 1.1-99 mg kg-1, Sm 0.04-9.31 mg kg-1, Pr 0.1-24.1 mg kg-1, and Nd 0.55-81 mg kg-1. The concentration of LREE among shoots did not show a linear relation either with the available fraction or total content. The screening also revealed Christella dentata (Forssk.) Brownsey & Jermy, Thelypteridaceae family, as a promising hyperaccumulator species. The concentrations of LREE among shoots of six individuals of this species were in the ranges from 115 to 1872 mg kg-1 for Ce, La 190-703 mg kg-1, Sm 9-48 mg kg-1, Pr 32-144 mg kg-1, and Nd 105-478 mg kg-1.

Frozen in time: Rangewide genomic diversity, structure, and demographic history of relict American chestnut populations.

American chestnut (Castanea dentata) was once the most economically and ecologically important hardwood species in the eastern United States. In the first half of the 20th century, an exotic fungal pathogen-Cryphonectria parasitica-decimated the species, killing billions of chestnut trees. Two approaches to developing blight-resistant American chestnut populations show promise, but both will require introduction of adaptive genomic diversity from wild germplasm to produce diverse, locally adapted restoration populations. Here we characterize population structure, demographic history, and genomic diversity in a range-wide sample of 384 wild American chestnuts to inform conservation and breeding with blight-resistant varieties. Population structure analyses suggest that the chestnut range can be roughly divided into northeast, central, and southwest populations. Within-population genomic diversity estimates revealed a clinal pattern with the highest diversity in the southwest, which likely reflects bottleneck events associated with Quaternary glaciation. Finally, we identified genomic regions under positive selection within each population, which suggests that defence against fungal pathogens is a common target of selection across all populations. Taken together, these results show that American chestnut underwent a postglacial expansion from the southern portion of its range leading to three extant genetic populations. These populations will serve as management units for breeding adaptive genetic variation into the blight-resistant tree populations for targeted reintroduction efforts.