Ficus Virens Research Articles

In-vitro enzyme inhibition, kinetics, molecular docking and dynamics simulation approaches to decoding the mechanism of Ficus virens in cholinesterase inhibition

In the current study, we investigate the bioactive potentials and mode of action of Ficus virens bark (FVB) extract against cholinesterase enzymes, via in-vitro cell-free cholinesterase inhibition kinetics, molecular docking, ADMET and dynamic simulation. Our results illustrated that FVBM extract showed better DPPH-free radical scavenging activity (IC50 = 17.8 ± 0.46 µg/ml) and AChE inhibitory ability (IC50 = 37.2 ± 0.43 µg/ml). Kinetics study explored the mixed inhibition of AChE enzyme by FVBM extract. Furthermore, molecular docking demonstrates that compounds Diethyl Phthalate and Dinopol NOP present in FVBM extract have good ΔG: −8.6 kcal/mol and Ki; 2.01 × 106 M−1 for AChE enzyme than BuChE enzyme (ΔG: −7.6 and Ki: 3.72 × 105 M−1). A simulation study of 200 ns of best two hits and Tacrine confirms that these compounds remained inside the binding pocket of proteins and formed a stable protein-ligand complex via interacting with key residue. Further studies could provide a better understanding of the therapeutic potential of these promising compounds.

Effects of growth space limitation on allometry of Ficus spp. In urban habitats

Tree morphological traits are related to the structural stability and their ability to provide ecological benefits such as carbon sequestration and water conservation. The allometric relationship can be used to construct the corresponding prediction equations in forests. However, the urban environment differs from the natural environment for trees. This study aims to enhance the urban tree growth model by classifying urban habitats. We achieved this by collecting morphological traits (DBH, height, crown depth, and width) commonly used in growth model researches of six Ficus spp. in Guangzhou, China, including Ficus virens, Ficus religiosa, Ficus elastica, Ficus benjamina, Ficus altissima, Ficus celebensis. We specifically examine how these trees grow in different urban settings. Urban habitats are classified based on growth space limitations, considering above-ground and underground. Results showed that certain morphologies in urban habitats did not conform to allometry (R2 < 0.4), and the model fitted with height as independent variable is better than that fitted with DBH. The model parameter following allometric relationship with tree height as the independent variable showed no significant difference, but the fit was worse in different urban habitats. On the contrary, models with DBH as the independent variable showed differences, for example, the allometric exponent of maximum crown width relative to DBH were 0.915 and 0.557 in two different habitats. Crown depth and tree height showed significant and stable allometry in the three habitats. The response of tree morphology to different habitats varied, and the allometric relationships among morphological traits showed differences in habitats where the growth space was limited. This underscores the considerable effect of the urban environment on urban tree growth models. Consequently, we recommend developing a series urban tree growth models tailored to different urban habitats to accurately quantify urban ecosystem services for assessing their sustainability in urban development and planning.

Evolvement of Spatio-Temporal Pattern and Driving Forces Analysis of Ancient Trees Based on the Geographically Weighted Regression Model in Guangzhou and Foshan, China

Ancient trees play an important ecosystem service role in high-density cities, revealing the zonal distribution characteristics of vegetation under climate influence. The ancient trees in Guangzhou and Foshan in 2018 and 2023 were taken as study objects to explore the evolution of their spatio-temporal patterns and to analyze the spatial differentiation characteristics of their driving factors using the geographical weighted regression (GWR) model. The results showed the following: (1) The ancient trees in Guangzhou and Foshan were composed of typical subtropical evergreen broad-leaved forest communities, mainly represented by broad-leaved species of evergreen dicotyledonous plants. The dominant species mainly included Litchi chinensis, Ficus microcarpa, Canarium pimela, Ficus virens, and Dimocarpus longan. However, there was a significant difference between Guangzhou and Foshan. (2) The number of ancient trees in Guangzhou showed negative growth, while Foshan saw a significant increase. However, species diversity in both areas increased, with the highest diversity in the northeast, higher diversity in the south-central part, and lower diversity in the western and northwestern parts. (3) The maximum kernel density of ancient trees in Guangzhou and Foshan differed 22-fold, indicating a spatial distribution pattern of multiple clusters. (4) The GWR model effectively explained the driving factors of the heterogeneity of the spatial distribution of ancient trees. The results showed that artificial disturbance was the most important factor affecting the spatial distribution of ancient trees in high-density urban agglomerations in the same vegetation zone. The study clarified the characteristics of the spatial distribution and species diversity of ancient trees in the region, revealed the driving factors for the evolution of the spatial pattern of ancient trees in highly urbanized areas, and provided guidelines for policies and measures for enhancing biodiversity and conserving germplasm resources in the region.

Transcriptome Analysis Reveals That FvPAP1 Genes Are Related to the Prolongation of Red-Leaf Period in Ficus virens.

Ficus virens is a deciduous tree that is highly valuable both economically and medicinally. Like other plants with 'red young leaves', the red-leaf period of most F. virens trees lasts only a few days, and the red leaves have little ornamental value. However, in recent years, some lines of F. virens with bright red young leaves and a prolonged red-leaf period have been utilized for urban greening. To explore the mechanism of the different lengths of the duration of F. virens leaves, we analyzed the physiology and changes in gene expression during the development of two varieties of leaves. The detection of anthocyanin in different developmental stages of the F. virens leaves showed that the changes in color of the red leaves of F. virens were primarily caused by the change in anthocyanin content. A transcriptome analysis showed that the expression of genes related to the biosynthesis of anthocyanin changed significantly during the development of leaves. A MYB gene FvPAP1, which was consistent with the change in anthocyanin content, was identified. A real-time quantitative reverse transcription PCR analysis and heterologous expression transgenic studies showed that FvPAP1 promoted the biosynthesis of anthocyanins. The difference in the expression of FvPAP1 in time and intensity in the young leaves may be the reason for the difference in the duration of the red-leaf period in different lines of F. virens. A sequence analysis showed that the cDNA sequence of FvPAP1 was polymorphic, and possible reasons were discussed. These results can provide insight for similar studies on the mechanism of the formation of red coloring in other woody plant leaves and provide molecular targets to breed new materials with more prolonged red-leaf periods in F. virens.

Targeting Epidermal Growth Factor Receptor with Ficus virens Metabolites to Manage Cancer Progression: Molecular Docking and ADME Study

Introduction: Targeting epidermal growth factor receptor (EGFR) has been used in the treatment of several cancer types where EGFR has a notable involvement in signalling pathways. Medicinal plants are the oldest and healthiest source of medication used in modern pharmacological therapy. Previous research indicates that the compounds found in Ficus virens stem bark have significant therapeutic properties against a range of illnesses, including cancer. Therefore, in this study, molecular docking research was conducted to determine the binding interactions and affinity of secondary metabolites predicted in F. virens methanolic extract with the target protein, EGFR. Materials and Methods: Three-dimensional (3D) conformers of the secondary metabolism products and adenosine triphosphate (ATP) were collected from PubChem on 5 January 2024. The 3D structure of EGFR and its inhibitor was retrieved from the Protein Data Bank (PDB) databank and ligands and proteins were converted to AutoDock-compatible format and then the energy minimisation was performed by the Open Babel in PyRx. Finally, using PyRx-Python 0.8, molecular docking was done, and using Discovery Studio, visualisation was done as well. The grid box dimensions were specified at 30 Å ×30 Å ×25 Å, and the physiochemical property evaluation was done by the SwissADME online server. Results: In this study, molecular docking assessed 14 compounds, including phytochemicals and ATP, for their binding with EGFR (PDB Id: 1XKK). Redocking of lapatinib validated the results. Natural chemicals showed binding energies from −4.0 to −7.8 Kcal/mol, with oleic acid and iso-caryophyllene demonstrating promising interactions, sourced from F. virens. Despite some limitations, these compounds exhibit potential for EGFR-targeted drug development, despite one Lipinski’s rule violation. Conclusions: EGFR inhibitory activities of iso-caryophyllene and oleic acid, which were identified in the F. virens methanol extract, were remarkable and higher than that of the substrate; their potential opens up exciting new possibilities for moving forward with cancer treatment. It is encouraged to further investigate the in vivo effectiveness of iso-caryophyllene, by means of animal models and cell lines.

Phytochemical investigation and experimental evaluation of Panchavalkala for Lekhana Karma w.s.r. to Antihyperlipedemic Activity

Panchavalkala the barks of five trees i.e., Nyagrodha (Ficus benghalensis L.), Udumbara (Ficus racemosa L.), Ashwatha (Ficus religiosa L.), Plaksha (Ficus virens Aiton) and Parisha (Thespesia populnea (L.)Sol.ex Correa) are also known as Pancha Ksheeri Vrikshas in use since Vedic period. The plant samples were collected in Sharad Rutu (late autumn) from their natural habitat, extracted using ethanol and water and subjected for the phytochemical analysis. The study was aimed to evaluate Antihyperlipidemic effect (Lekhana Karma) of Panchavalkala Bark extracts individually and in combination (1:1:1:1:1) both in ethanolic and aqueous extracts on serum lipid profile in Cafeteria died (HFD) induced hyperlipidemia in SD rats. The animals were divided into fifteen groups of six animals each. The normal control group continued to be fed laboratory pellet chow ad libitum. The cafeteria diet-control group received the cafeteria diet in addition to the normal pellet diet (NPD). The remaining 13 groups were fed with the cafeteria diet and NPD along with standard control Atorvastatin 10mg/kg and the test drug p.o for 30 days. Treatment with the test substance PVK AE and PVK EE at doses of 200mg/kg body weight p.o. controlled and regulated the HFD induced weight gain, glucose and lipids in the blood when compared against high fat diet control (P&lt; 0.05). PVK bark extracts are capable of exhibiting significant antihyperlipidemic activity in HFD induced SD rats. Taken together, this study strongly suggests that PVK bark extracts might be an efficient way for treatment of hyperlipidemia.

Cd(II) and Pb(II) adsorption in karst soils amended with litter extract from Ficus virens

In this study, different proportions of Le were used to amend purple, yellow, and yellow–brown soils of karst areas to investigate the effect of litter extract (Le) from Ficus virens on Cd(II) and Pb(II) adsorption in karst soils. The basic physicochemical properties of Le-amended karst soils were determined, and the microscopic morphology of Le-amended karst soils was detected. The batch method was used to study the isothermal adsorption characteristics of Cd(II) and Pb(II) adsorption on different Le-amended karst soils. Physicochemical properties and microscopic morphology results showed that Le was amended on the karst soil surface and changed the surface properties of the karst soil. The maximum adsorption capacity range of Cd(II) and Pb(II) by Le-amended karst soils was 92.10–241.61 and 108.91–262.12 mmol/kg, respectively, and the peak value was reached when the karst soils were amended with 20 % of Le. Increasing the pH and temperature were beneficial to Cd(II) and Pb(II) adsorption in each Le-amended karst soil. The adsorption amount of Cd(II) and Pb(II) initially increased and thendecreased with the increase in ionic strength. Cd(II) and Pb(II) adsorption was a spontaneous, endothermic, and entropy-increasing process, and electrostatic attraction, precipitation, complexation, and ion exchange were the main adsorption mechanisms. The adsorption amount of Cd(II) and Pb(II) by Le-amended yellow–brown soil maintained approximately 85 % of original sample after three rounds of regeneration.

Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects

Vegetation reinforcement for slopes has been recognized as an environment-friendly measure and has been widely adopted in engineering practice. However, the stability analysis of vegetation reinforcement for slopes has mainly been discussed for an infinite slope and common grass and scrub plant species. This study proposes a procedure for analyzing the stability of a finite slope reinforced with Ficus virens under transpiration and rainfall conditions. A simplified empirical model for characterizing root cohesion and triaxial testing is utilized to quantify the mechanical effect of roots on rooted soil shear strength. A numerical modeling technique with COMSOL Multiphysics is used to investigate the hydrological effect of roots. The combination of these two effects forms an expression for the unsaturated shear strength of rooted soils. The stability of a vegetated soil slope is then investigated in terms of safety factors and failure mechanisms, with/without considering rainfall. The results show that the stability solutions without consideration of the roots’ mechanical and/or hydrological effects are overly conservative. The hydrological contribution to slope stability could also be partially preserved under short-term rainfall, and as rainfall continues, the hydrological effect is weakened, while the mechanical reinforcement is assumed to be unchanged. In the meantime, the hydrological contribution to slope stability is susceptible to atmospheric conditions, which indicates a favorable effect on water uptake and an adverse consequence for water infiltration.

Mitigating airborne microplastics pollution from perspectives of precipitation and underlying surface types.

The issue of airborne microplastics (AMPs) pollution is receiving increasing attention, but effective solutions are still limited. In this study, AMPs were collected in pairs from an open space and under a tree (Ficus virens) in the suburb of Chengdu, southwest China, to investigate the current pollution status. The meteorological factors and underlying surface types were analyzed to investigate whether these factors could influence and mitigate the pollution of AMPs. The results showed that the fibrous AMPs accounted for the vast majority and the dominant polymers were polypropylene-polyethylene (PP-PE) and polypropylene (PP), with an average deposition flux of AMPs of 192 n/m2/d (22.41 µg/m2/d). Rainfall was found to have the prolonged scavenging efficiency for AMPs, which could extend to 8 to 48 hours after the end of rainfall, and this is a new insight into the relationship with meteorological factors. Interactions between the key underlying surface types and AMPs were also studied. The representative tree species (Ficus virens) had a low interception rate of 6.25% for AMPs and retained mainly small-sized AMPs and more fibers. The masses of AMPs loaded into Chengdu rivers could reach 1149 kg annually, with the unit mass load of 13.6 kg/km2 in urban rivers and 8.2 kg/km2 in suburban rivers. The masses intercepted by trees and bushes throughout the city only offset the masses loading in rivers, and open or sparse buildings were found to be sensitive areas for AMPs, which indicated the urgent need to control and mitigate the pollution of AMPs, especially in these sensitive areas. This work comprehensively analyzed the AMPs pollution from various perspectives and attempted to find ways to mitigate this pollution.

Competition and synergistic mechanisms of species in Phyllostachys edulis-Alsophila spinulosa association based on niche theory.

We examined the niche characteristics and interspecific covariant relationship of main species in Phyllostachys edulis-Alsophila spinulosa association in Chishui A. spinulosa National Nature Reserve under P. edulis disturbance condition, and analyzed the mechanism of competition and coexistence across different species. The results showed that there were 67 species from 53 genera and 40 families in the association. The importance values, Shannon niche breadth index (BS), and Levins niche breadth index (BL) of P. edulis were the largest, indicating its absolute dominant status in association. The importance value and BL of A. spinulosa ranked the second, while BS was the third. There were 190 pairs of 20 main species. The niche overlap between P. edulis and A. spinulosa was the largest, with niche overlap value of 0.64. 71.6% of species pairs had niche overlap of less than 0.2, indicating low niche overlap and high degree of niche differentiation among species. The overall association of main species in association was significantly positive, and the community was relatively stable. The correlation among the main species was not significant, the linkage was not strong, and the species were independent from each other. P. edulis showed significant positive correlation with A. spinulosa, Brassaiopsis glomerulata, Ficus virens, and Mallotus barbatus, while P. edulis showed significant negative correlation with Mallotus philippensis, Cinnamomum glanduliferum, and Machilus gamblei. Niche difference and fitness between P. edulis and natives affected the coexistence and competition among species. Controlling the expansion of P. edulis and limiting the size of species with negative correlation with A. spinulosa could create a favorable living environment for A. spinulosa.

Green preparation of silanized carbon dots with ficus virens leaves as a potent antibacterial agent and an effective fluorescent sensor of iron ion

In this work, a green and economical strategy to prepare silanized carbon dots (Si-CDs) based on Ficus virens leaves was carried out. The prepared difunctional Si-CDs showed high water-solubility and favorable photostability. The morphology and surface functional groups were analyzed by TEM, FT-IR, and XPS. Si-CDs had amorphous nature with no crystal lattice and the average diameter of 1.95 nm. Some functional groups like nitrogen groups, oxygen groups, and silicon groups were discovered. Attributing to the small size of Si-CDs, positive charges, and the generation of singlet oxygen and hydrogen radicals, Si-CDs possessed effective antibacterial activity. The minimum inhibitory concentration of Si-CDs against Escherichia coli and Staphylococcus aureus was 0.078 mg/mL. Moreover, Si-CDs exhibited selective and sensitive fluorescence quenching response to Fe3+ through static quenching process. The limit of detection was 0.84 μmol/L in the liner range of 5–50 μmol/L. Analysis of real samples led to 99.8–102.0% recoveries and <1% relative standard deviation. Consequently, this work discovered a new, green, economical silanized carbon dot with the potential application as a potent antibacterial agent and an effective fluorescent sensor of iron ion.

Phytochemical Investigation and in Vitro Antioxidant Activity of Panchavalkala Bark Extracts

Natural antioxidants have an important role in the prevention of many age-related diseases and promotion of health. Among natural antioxidants from plants, flavonoids and other phenolic compounds are potent antioxidants and chelating agents. Panchavalkala the barks of five trees i.e. Nyagrodha (Ficus benghalensis L.), Udumbara (Ficus racemosa L.), Ashwatha (Ficus religiosa L.), Plaksha (Ficus virens Aiton) and Parisha (Thespesiapopulnea (L.)Sol.ex Correa) are also known as Pancha Ksheeri Vrikshas in use since Vedic period. Barks of these trees are dried in shade and are used for different formulations (Pancha Kashaya Kalpanas), in different pathological conditions, especially as wound healing, gynecological disorders and etc. The plant samples were extracted using ethanol and water, and subjected for the phytochemical analysis. It was confirmed that samples contain many biologically active compounds like flavonoids, polyphenols, tannins, alkaloids, glycosides and terpinoids etc. The marker compound of each trial drug and the quantitative analysis has been carried out by high performance liquid chromatography. The antioxidant study was done by using in vitro method 1, 1­-diphenyl-2-picryl-hydrazyl (DPPH) radicle scavenging assay. The marker compounds caffeic acid and gallic acid were quantified in each extract for their quality and efficacy. PVK barks showed high free radicle scavenging activity as evidenced by the low IC50 values in DPPH (EE PVK- 20.46 µg/ml, AE PVK-37.79 µg/ml, EE T.poulenea-22µg/ml, AE T. poulenia- 23.31µg/ml AE F. benghalensis- 25.53µg/ml, EE F. benghalensis- 26.23µg/ml, EE F. religiosa – 34µg/ml). Quercetin- IC50 value 4.026µg/ml is used as standard.&#x0D; The results of the study demonstrated that PVK barks possess phyto-constituent’s viz. tannins, flavonoids, polyphenols etc. and has potential antioxidant activity. Thus these barks have good therapeutic potential as natural antioxidant and might be used in life style related conditions like hyperlipidemia, diabetes, obesity, cardiovascular disorders and etc.

Microclimate effects and influential mechanisms of four urban tree species underneath the canopy in hot and humid areas

Purpose: Urban trees play a key role in ameliorating extreme urban climates in cities. At the micro-level, it is crucial to investigate the variations in microclimates affected by the canopies of different tree species. The significance of this research is to provide scientific evidence for the selection of tree species in urban planning that can improve the local microclimate. This study examines the factors of microclimate (air temperature, relative humidity, wind environment, and solar radiation) underneath the canopy of four different evergreen tree species in hot and humid areas. Furthermore, the correlation between the physiological characteristics of these tree species and microclimate was statistically analyzed using data on the physiological parameters of the trees and microclimate factors.Methods: In this study, four tree species were selected for field measurements: Ficus microcarpa L. f., Ficus virens Aiton, Bauhinia x blakeana Dunn, and Cinnamomum camphora (L.) Presl. We used the HOBE (H21-0024, onset) to measure three climatic parameters (Temperature, Relative Humidity, and Instantaneous Wind Speed), and the Li-6400 Portable Photosynthesis System to measure five plant physiological parameters: Stomatal Conductance (Gs), Leaf Temperature (Tleaf), Leaf Surface Relative Humidity (RHsfc), Photosynthetically Active Radiation (PAR), and Leaf-level Vapor Pressure Deficit (Vpdl). The observations were conducted during winter (January 16 - January 22) and summer (August 7 - August 22). The investigation periods were 9:00–11:00, 12:00–14:00, and 16:00–18:00, and data were recorded at 15-min intervals. The observational data obtained were analyzed using statistical methods, including one-way analysis of variance, Pearson correlation coefficient, and multiple regression analysis.Results: The results of this study indicated that the four tree species being measured had different effects on the microclimate at the sites in both the winter and summer seasons. During the 7-day observation in the summer, the cooling effect of the four tree species was significant. The relative humidity underneath the canopies was 3%–11% higher than that of weather stations. The instantaneous wind speed in the afternoon was relatively higher than at other times. The solar radiation intensity was dramatically reduced by 85%–95%. During the 7-day observation in the winter, the trees had a warming effect in the morning. The relative humidity underneath the canopies was 10%–20% higher than that of the weather stations. The areas underneath the canopies were windless in the afternoon. The solar radiation intensity was reduced by 78%–95%. Ficus microcarpa was found to be one of the most effective tree species for increasing the relative humidity and reducing solar radiation intensity in hot and humid areas. Additionally, the highest instantaneous wind speed was observed in the areas underneath the canopies of F. virens and C. camphora. Statistical tests revealed that the air temperature and the instantaneous wind were extremely significantly correlated with Tleaf and RHsfc.Conclusion: The four urban tree species studied had varying degrees of effect on air temperature, relative humidity, wind speed, and reducing solar radiation intensity in the areas underneath their canopies. Furthermore, these trees demonstrated varying abilities to improve microclimate conditions in different seasons. The four trees had a cooling effect in the summer. The instantaneous wind speed was calm in the afternoons during the winter in contrast to being relatively high speed in the afternoons during the summer. This characteristic is beneficial to warmth in winter and coolness in summer. In terms of the internal influence mechanisms, the results of the analysis indicated that microclimate factors were significantly correlated with the physiological parameters of the trees. Tleaf, RHsfc, and Vpdl were significant physiological parameters and had different contribution rates to microclimate factors.

Ternary Mg-B-S co-modified Ficus virens biochar for ultra-high adsorption of rhodamine B in lab-scale and field-scale application: Adsorption behavior and mechanisms

To boost the adsorption activity of Ficus virens biochar for dye removal, S-doped biochar was co-modified by MgO and B2O3 (Mg-B/S-BC) via one-pot sulfurization. Mg-B/S-BC exhibits the higher adsorption capacity than S-doped biochar, MgO/biochar and B2O3/biochar for rhodamine B (RhB). The adsorption capacity of optimal Mg-B/S-BC is 1195.25 mg g−1, and declines to 1142.97 mg g−1 after nine cycles. The adsorption isotherms and kinetics of S-biochar based composites are well matched with Langmuir and second-order models, respectively. The mechanism of RhB adsorption on 4d-Mg-B/S-BC composites is through electrostatic attraction, H-bonding and ion exchange interactions, and it is a spontaneous process of physical adsorption and heat absorption. The field-scale results suggest that the adsorption capacity of optimal Mg-B/S-BC is 487.01 mg g−1, while reduces to 429.63 mg g−1 for RhB after nine cycles. The optimal Mg-B/S-BC exhibits the excellent adsorption activity for field-scale removal of tetracycline hydrochloride, ciprofloxacin, and methyl orange. Hence, Mg-B/S-BC composite is a promising material for industrial application in wastewater purification.

Determination of chlorogenic acid and rutin in extractive solution of ficus virens leaves by HPLC-PDA

Determination of chlorogenic acid and rutin in extractive solution of ficus virens leaves by HPLC-PDA

Analysis of Structure, the Composition of Vegetation, and Diversity of Epiphytes and Their Hosts

The tourist area of Kali Bak Kampung Harapan Sentani Jayapura Regency is one of the buffer zones for the Cycloop Mountains nature reserve which has the function of a rainwater catchment area and supply of drinking water for the people of Jayapura Regency and City, but currently, the tourist spot is experiencing intensive disturbances and threats. This condition is the reason for this study to be carried out to analyze epiphytic plant vegetation and their hosts in the Kali Bak tourism area, Harapan Sentani Village, Jayapura Regency. The purpose of this study was conducted to determine the structure and composition of the vegetation as well as the diversity of epiphytes and their hosts at the Kali Bak tourist spot, Harapan Sentani Village, Jayapura Regency. Data collection was carried out using transect methods, documentation methods, and plot methods. There are 25 observation plots with a plot size of 20 x 20 meters which are placed on the right and left of the transect line. The results showed that 5 families of 8 species were Asplenium nidus L., Davallia trichomanoides BL., Dendrobium sp, Drynaria quercifolia (L). J.sm., Drynaria rigidula (Sw.).Bedd., Microsorum sp, Microsorum punctatum, and Nephrolepis falcata (Cav.) C. Chr. As for the host tree species, 6 families were obtained consisting of 6 species including Alstonia scholaris (L.) R. Br., Calophyllum inophyllum, Cycas rumphii Miq., Ficus virens Aiton., Gymnostoma papuana Miq., Intsia bijuga (Colebr.) OK. The overall diversity index for epiphytic plants, which is 1.98, is moderate. The overall diversity index for host trees is 1.26 which is moderate

Environmental Factors Driving the Spatial Distribution Pattern of Venerable Trees in Sichuan Province, China.

Venerable trees are important natural resources and cultural heritage, offering historical, ecological, social and economic value. However, global warming and anthropogenic activities have threatened their welfare and survival. A comprehensive understanding of their current and future spatial patterns, vis-á-vis environmental conditions, can inform the co-management of sustainable resource use and conservation. We employed the existing spatial occurrence data and environmental variables (bioclimate and elevation) to simulate the optimal habitats for venerable trees in China's Sichuan Province. We evaluated the current and future climate scenarios of 2100 with double CO2 concentration. The BIOCLIM and QGIS spatial analyses assessed the primary factors of geographical distribution. The results identified 10,720 venerable trees from 123 species, 81 genera and 42 families. Cupressus funebris dominated, with the maximum importance value, followed by Ginkgo biloba, Ficus virens var. sublanceolata, and Phoebe zhennan. The elevation distribution of tree abundance and species richness demonstrated a unimodal pattern, skewing to the low-elevation end, with a concentration in the 600-1500 m low-medium altitude. The majority of trees and excellent habitats were found in eastern Sichuan with a less harsh terrain and climate. The bio3 (isothermality) and bio7 (temperature annual range) factors significantly influenced tree occurrence. Temperature imposed a greater effect on distribution than moisture under the current climate scenario. For the future climate-change scenario, the suitable habitats were predicted to maintain an overall stable pattern, with largely contiguous expansions of better habitats. However, climate warming would shrink the excellent habitats on the plains. The findings can inform strategies and guidelines for venerable-tree conservation in Sichuan. Furthermore, vulnerable areas could be identified. The future range expansion sites could be enlisted to cultivate new trees to replenish the venerable-tree pool. Habitat patches that remain sustainable could provide refugia with the potential for protected-area designation.

Isotopic Composition (δ15N and δ18O) of Urban Forests in Different Climate Types Indicates the Potential Influences of Traffic Exhaust and Relative Humidity

Previous studies have shown that climatic and anthropogenic factors influence the variations in the stable isotope signature of tree materials in an urban ecosystem. However, the responses of urban trees to various anthropogenic and precipitation interventions are unclear. To fill the research gap, the isotopic composition (δ15N and δ18O) and total nitrogen content of the soil-plant system of urban forests were measured, focusing on typical urban tree species (Populus tomentosa and Ficus virens). The research was done under various land uses in China’s Beijing and Shenzhen megacities (with different humidity conditions). The linear mixed-effect model revealed that the δ15N values in the leaves of roadside Ficus virens were significantly higher than those in urban park sites, away from the road (δ15N difference = 7.2‰). In contrast, Populus tomentosa leaves exhibited a non-significant difference (δ15N difference = −1.8‰). Further regression analysis revealed that the variations in δ15N in tree leaves could be attributed to the proximity to highways, suggesting the influence of vehicle exhaust on δ15N values in roadside trees. The linear mixed-effect model also revealed δ18O values significantly higher in Populus tomentosa leaves than in Ficus virens leaves. To assess the influence of humidity conditions on δ18O values in the leaves, the ratio of the atmospheric and intercellular vapor pressures (ea/ei) of tree canopies was estimated. The result revealed that the ea/ei of Ficus virens was significantly higher than for Populus tomentosa, ascribed to the variation in the humidity conditions of the two megacities. These results highlight that urban trees can potentially serve as bioindicators for atmospheric pollution and humidity. Our findings highlight the ecophysiological responses of urban forests related to N and O as they vary according to traffic exhaust and relative humidity. Consequently, they are potentially valuable indicators of urban atmospheric contamination, forming a nature-based solution for citizen welfare improvement.

First Report of Phytoplasma Belongs to 16SrV Group Associated with Witches'-broom Disease of Taxillus chinensis in China.

Taxillus chinensis (DC.) Danser is a hemiparasitic shrub, widespread in Southern China (Fu et al., 2001). T. chinensis can parasitize a wide range of species (e.g., Camellia spp., Ficus virens and Osmanthus fragrans), which obviously suppressed host growth by robbing nutrient and water through haustorium, causing considerable tree damage. During field visits to Dongguan (22°86'N, 13°97'E) and Guangzhou (23°19'N, 113°31'E), Guangdong Province, in April-July 2021, the typical phytoplasma-suspected symptom manifested as stunting, leaflet, leaf chlorosis and witches'-broom were observed in almost 36% of T. chinensis plants. Leaf samples were collected from six randomly collected plants with symptoms and six symptomless plants (Fig 1). Among them, half of T. chinensis plants parasitized on the host Elaeocarpus sylvestris, the other half on the O. fragrans. No apparent symptoms were observed on both two host plants. Total DNA was extracted from 0.5 g fresh leaf of T. chinensis plants with and without symptoms, as well as two host plants E. sylvestris and O. fragrans, using the CTAB method (Doyle et al., 1990). Nested polymerase chain reactions (PCRs) were performed on DNA extracts of all tested plants with primer pairs of P1/P7 and R16mF2/R16mR1 for 16S rRNA gene (Lee et al., 1993) and rp(v)F1/rpR1 for rp gene (Lee et al., 1998). All amplicons were obtained from symptomatic samples of T. chinensis and host plant E. sylvestris, whereas no such products resulted from DNAs of symptomless plants and O. fragrans. The amplicons were purified and sequenced by Sanger method (Rui Biotech, Guangzhou, China). The amplicon of 16S rRNA and rp genes is 1346 bp and 938 bp, respectively. BLAST comparison of the 16S rRNA (accession no. OL412744) and rp (accession no. OL473789) sequences of the T. chinensis witches'-broom phytoplasma yielded 99.6% sequence identity with those of phytoplasmas of group 16SrV jujube witches'-broom (JWB) phytoplasma (accession no. CP025121 for 16S rRNA gene and AF396941 for rp gene). The 16S rRNA gene sequence of phytoplasma in host plant E. sylvestris (accession no. OM885990) is 99.7% similarity to the 'Elaeocarpus zollingeri' yellows phytoplasma (accession no. LC257960) and 99.4% similarity to the 'Elaeocarpus sylvestris' decline phytoplasma (accession no. MW553140), but 95.8% similarity to the 16S rRNA gene of phytoplasma in T. chinensis. The virtual RFLP tool, iPhyClassifier delineated the T. chinensis phytoplasma (accession no. OL412744) to group 16SrV-B (accession no. AB052876) with the similarity coefficient 1.0 (Fig 2), and phytoplasma in E. sylvestris to group 16Sr group XXXII with the similarity coefficient 0.97. Phylogeny analyses of 16S rRNA and rp genes (MEGA version 7.0.14, USA) using reference phytoplasmas from GenBank confirmed sequencing results and placed the T. chinensis phytoplasma in group 16SrV-B (Fig. 3 and 4). In China, the 16SrV-B phytoplasma group has been reported in Amaranthus retroflexus (Yang et al., 2011), Liriodendron chinense (Li et al., 2012), Prunus salicina (Gao et al., 2020) and sweet potato (Li et al., 2021). This is the first report of a 'Ca. Phytoplasma ziziphi', 16SrV-B related phytoplasma associated with parasitic T. chinensis in China. The results of this study indicate that T. chinensis could be a vector to spread phytoplasmas 16SrV group through parasitism and this can be helpful for related research.

Determination of coumarin-3-carboxylic acid in the liver and heart tissue of Sprague-Dawley rats after intragastric administration of extractive of leaves of F. virens var. sublanceolata by HPLC

AbstractThe study was aimed to validate and optimize high performance liquid chromatographic (HPLC) method for the determination of coumarin-3-carboxylic acid (C3A) in the heart and liver issue of Sprague-Dawley (SD) rats after intragastric administration of extractive of leaves of Ficus virens var sublanceolata. And simple ADME and target prediction analyses were performed for C3A. Ethyl acetate was employed to precipitate protein with appropriate sensitivity and acceptable matrix effects. The satisfactory separation was developed on an ODS2 column (4.6 mm × 250 mm, 5 μm) by gradient elution with a methanol-acetic acid solution (pH = 3.0) as the mobile phase. The flow rate was 1.0 mL min−1, the column temperature was maintained at 30 ± 2 °C, the injection volume was 20 μL, and the detection wavelength was set as 309 nm. The method was fully validated in terms of selectivity, linearity, accuracy, precision, extraction recovery and stability. The results of the ADME analysis found that C3A has excellent characteristics of drug-likeness, consistent with good bio-absorption. And the predicted 12 target protein belongs to the amine oxidoreductase and carbonic anhydrase target class. This method is simple, rapid, sensitive, and accurate for the determination of coumarin-3-carboxylic acid in the heart and liver tissue of SD rats.