HPLC/ESI-QTOF-MS/MS based untargeted metabolomics authentication of Taxus × media six tissues.

INTRODUCTION: Taxus media (Taxus × media Rehder) is renowned for its high paclitaxel content, serving as a major source for industrial paclitaxel production. In addition to paclitaxel, T. media contains a diverse range of metabolites, including flavonoids, alkaloids, and terpenoids, which have been shown to possess antioxidant, antibacterial, anti-inflammatory, and immunomodulatory effects. However, these compounds have not been thoroughly studied as key metabolites in T. media. OBJECTIVE: The untargeted metabolomics analysis of six T. media tissues provides new insights into the development and utilization of T. media metabolites. METHOD: The extracts from six tissues of T. media were analyzed and subjected to analysis using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) and chemometric techniques. RESULTS: Using a reliable HPLC-Q-TOF-MS/MS method, we identified 312 compounds in six T. media tissues, including 214 previously unreported in T. media. To identify characteristic compounds across different tissues, 34 metabolites were further screened. KEGG metabolic pathway analysis revealed that these compounds primarily occur in the metabolic pathways of terpene glycosides, flavans, and O-methylated flavonoids. CONCLUSION: This study initially utilized an HPLC-QTOF-MS/MS-based metabolomics approach to assess the metabolites in different tissues of T. media, providing a basis for their utilization and management.

Chemodiversity and Bioactivity of the Essential Oils of Juniperus and Implication for Taxonomy.

The essential oils of Juniperus are highly beneficial medicinally. The present study aimed to assess the chemodiversity and bioactivity of Juniperus formosana, Juniperus przewalskii, Juniperus convallium, Juniperus tibetica, Juniperus komarovii, and Juniperus sabina essential oils from the Qinghai-Tibet Plateau. The results revealed 92 components in six essential oils: α-pinene (2.71-17.31%), sabinene (4.91-19.83%), and sylvestrene (1.84-8.58%) were the main components. Twelve components were firstly reported in Juniperus oils, indicating that the geographical location and climatic conditions of the Qinghai-Tibet Plateau produced the unique characteristics of Juniperus essential oils. The chemodiversity of Juniperus essential oils varied greatly, with J. sabina having the most recognized components (64) and the highest chemodiversity (Shannon-Wiener index of 3.07, Simpson's diversity index of 0.91, and Pielou evenness of 0.74). According to the chemodiversity of essential oils, the six plants were decided into the α-pinene chemotype (J. formosana), hedycaryol chemotype (J. przewalskii, J. komarovii, J. convallium, J. tibetica), and sabinene chemotype (J. sabina). PCA, HCA and OPLS-DA showed that J. formosana and J. sabina were distantly related to other plants, which provides a chemical basis for the classification of Juniperus plants. Furthermore, bioactivity tests exhibited certain antioxidant and antibacterial effects in six Juniperus oils. And the bioactivities of J. convallium, J. tibetica, and J. komarovvii were measured for the first time, broadening the range of applications of Juniperus. Correlation analysis of components and bioactivities showed that δ-amorphene, ß-udesmol, α-muurolol, and 2-nonanone performed well in the determination of antioxidant activity, and α-pinene, camphene, ß-myrcene, as well as (E)-thujone, had strong inhibitory effects on pathogenic bacteria, providing a theoretical basis for further research on these components.

Sex-Related Differences on Chemical Composition, Anatomy, Histochemistry, and Biological Activities of Juniperus rigida.

Sex-related differences on phenolic profiles, chemical composition of essential oils, anatomy, histochemistry and biological activities (antioxidant and antibacterial activities) of Juniperus rigida needles collected from Yijun and Fugu region were first studied. In two regions, female and male had similar contents of total phenolic and total flavonoid. 10 phenolic compounds were analyzed by RP-HPLC, amentoflavone content was significantly higher in female than male in Yijun, and chlorogenic acid content was significantly higher in female than male in Fugu. 30 compounds (over 0.5 %) were detected in the essential oils, and the total contents of female were lower than male in Yijun. This difference mainly comes from Germacrene D, which was about twice as high in male as in female. Male needles had significantly larger mechanical tissue and phloem in Yijun. Histochemical analysis indicated that the phenols were stored in epidermal cells, sponge tissue, endodermis cells, edge of resin duct, stomatal bands, and the flavonoids were stored in epidermal cells, endodermis cells, edge of resin duct, stomatal bands. No sex-related differences were found in histochemical analysis, antioxidant activities (ABTS, FRAP) and antibacterial activities (9 strains). This preliminary study provided a reference for production practice and theoretical research of J. rigida.

Juniperus sabina L. as a Source of Podophyllotoxins: Extraction Optimization and Anticholinesterase Activities.

Juniperus sabina L. (J. sabina) has been an important plant in traditional medicine since ancient times. Its needles are rich in podophyllotoxin, a precursor compound to anti-tumor drugs. However, no systematic research has been done on J. sabina as a source of podophyllotoxins or their biological action. Hence, extracts of podophyllotoxin and deoxypodophyllotoxin were the main optimization targets using the Box-Behnken design (BBD) and response surface methodology (RSM). The total phenol content and antioxidant activity of J. sabina needle extract were also optimized. Under the optimal process conditions (ratio of material to liquid (RLM) 1:40, 90% methanol, and ultrasonic time 7 min), the podophyllotoxin extraction rate was 7.51 mg/g DW, the highest level reported for Juniperus spp. distributed in China. To evaluate its biological potential, the neuroprotective acetyl- and butyrylcholinease (AChE and BChE) inhibitory abilities were tested. The needle extract exhibited significant anti-butyrylcholinesterase activity (520.15 mg GALE/g extract), which correlated well with the high levels of podophyllotoxin and deoxypodophyllotoxin. This study shows the potential medicinal value of J. sabina needles.

Chemical composition, antibacterial activity and related mechanism of valonia and shell from Quercus variabilis Blume (Fagaceae) against Salmonella paratyphi a and Staphylococcus aureus.

BACKGROUND: Plant secondary metabolites and phytochemicals that exhibit strong bioactivities have potential to be developed as safe and efficient natural antimicrobials against food contamination and addressing antimicrobial resistance caused by the overuse of chemical synthetic preservative. In this study, the chemical composition, antibacterial activities and related mechanism of the extracts of the valonia and the shell of Quercus variabilis Blume were studied to determine its potential as a safe and efficient natural antimicrobial. METHODS: The phenolic compositions of valonia and shell extracts were determined by folin-ciocalteau colourimetric method, sodium borohydride/chloranil-based assay and the aluminium chloride method and then further identified by the reverse-phase HPLC analysis. The antibacterial activities of valonia and shell extracts were evaluated by the agar disk diffusion method and agar dilution method. The related antibacterial mechanism was explored successively by the membrane of pathogens effect, phosphorous metabolism, whole-cell proteins and the microbial morphology under scanning electron microscopy. RESULTS: The n-butanol fraction and water fraction of valonia along with n-butanol fraction of the shell contains enrich phenolics including ellagic acid, theophylline, caffeic acid and tannin acid. The n-butanol fraction and ethanol crude extracts of valonia exhibited strong antibacterial activities against Salmonella paratyphi A (S. paratyphi A) and Staphylococcus aureus (S. aureus) with the DIZ values ranged from 10.89 ± 0.12 to 15.92 ± 0.44, which were greater than that of the Punica granatum (DIZ: 10.22 ± 0.18 and 10.30 ± 0.21). The MIC values of the n-butanol fraction and ethanol crude extracts of valonia against S. paratyphi A and S. aureus were 1.25 mg/ml and 0.625 mg/ml. The related antibacterial mechanism of n-butanol fraction and ethanol crude extracts of valonia may be attributed to their strong impact on membrane permeability and cellular metabolism. Those extracts exhibited strong antibacterial activity according to inhibit the synthesis of bacterial proteins and seriously change morphological structure of bacterial cells. CONCLUSIONS: The n-butanol fraction and ethanol crude extracts of valonia had reasonably good antibacterial activities against S. paratyphi A and S. aureus. This study suggests possible application of valonia and shell as natural antimicrobials or preservatives for food and medical application.

Anatomical, Phytochemical, and Histochemical Study of Juniperus rigida Needles at Different Altitudes.

Needles of Juniperus rigida are used in Chinese traditional medicine for the treatment of brucellosis, dropsy, skin disease, and rheumatoid arthritis. This is the first study that reports anatomical structures of the J. rigida needles collected at different altitudes. The most common anatomical, phytochemical, and histochemical techniques and methods are used. The results show that anatomical structures and chemical composition change significantly at different altitudes. The main anatomical characters are significant xeromorphic structures (thick epidermis, hypodermis, and cuticle), a stomatal band, a developed vascular bundle, and a marginal resin duct. The xeromorphic structures become more pronounced with increasing altitude. The phytochemical and histochemical results demonstrate that the content of the main chemical compounds (phenols and terpenoids) basically increases at a higher elevation. Histochemical analysis localizes the phenols in epidermal cells, sponge tissue, endothelial layer cells, and stomatal bands, and the terpenoids in palisade tissue, sponge tissue, and the edge of the resin duct. This work reveals the relation between anatomy and chemistry in J. rigida needles, contributes to the quality control of its ethno-medicine, and provides the evidence to develop the commercial cultivation.

Polyphenols of Leaf, Litter and Soil of Pinus bungeana across China and Their Responses to Ecological Factors.

The importance of phenolic compounds for responding to various environmental conditions has been widely emphasized. However, the role of interactions between polyphenols and ecological factors, especially C, N, and P stoichiometry was little studied. Here, 15 sites across five provinces of Pinus bungeana in temperate regions of China were studied. The results showed that the higher values of total phenolic contents (TPC) of leaf and litter were distributed among the north distribution area of P. bungeana, lower values were in the south, whereas soil TPC were contrary to leaf and litter TPC. The stepwise regression, path analysis and decision index of path analysis for leaf TPC and ecological factors showed that altitude had the most direct impact on leaf TPC. Moreover, the principal determinants of leaf, litter and soil TPC were soil C/P ratios, longitude, and soil N/P ratios, respectively. In addition, the leaf, litter and soil TPC of P. bungeana were limited by soil C/N ratios, mean annual temperature, and soil P, respectively. Overall, our study provided evidence that ecological factors affected strongly the leaf, litter and soil TPC of P. bungeana.

Metabolite Profiles, Bioactivity, and HPLC Fingerprint of Different Varieties of Eucommia ulmoides Oliv.: Towards the Utilization of Medicinal and Commercial Chinese Endemic Tree.

Eucommia ulmoides Oliv. is widely regarded in China as a precious medicinal and commercial endemic tree. Due to cross-breeding or natural variation of E. ulmoides, the metabolite composition may vary significantly, making control of the medical quality difficult. In order to improve the rational development and utilization, the quality of seven varieties of E. ulmoides were evaluated based on metabolite profiles (total phenolic, total flavonoid, gutta-percha, aucubin, geniposidic acid, chlorogenic acid, geniposide, pinoresinol diglucoside, rutin, hyperoside, and astragalin), bioactivities (in vitro, in vivo antioxidant activities, and antibacterial activities) and HPLC fingerprint combined with chemometrics analysis. On this basis, the differences of medicinal parts (leaf and bark) were further carried out. For the traditional use of bark, Purple-leaf E. ulmoides was the most suitable. For the use of leaf, Qinzhong 1 and Purple-leaf E. ulmoides were appropriate. HPLC fingerprint analysis showed that significant differences in metabolite profiles exist among seven varieties of E. ulmoides. Combined with chemometrics analysis, seven varieties of E. ulmoides were divided into three groups from the use of leaf and bark. The analysis not only evaluated quality of seven varieties of E. ulmoides, but also could distinguish different varieties and different regions of origin. The results can provide theoretical basis for E. ulmoides resources utilization and cultivation of fine varieties.

Allelopathic Effects, Physiological Responses and Phenolic Compounds in Litter Extracts of Juniperus rigidaSieb. et Zucc.

The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter.

Synergistic effects and related bioactive mechanism of Potentilla fruticosa L. leaves combined with Ginkgo biloba extracts studied with microbial test system (MTS).

BACKGROUND: Potentilla fruticosa, also called "Jinlaomei" and "Gesanghua", is widely used as folk herbs in traditional Tibetan medicine in China to treat inflammations, wounds, certain forms of cancer, diarrhoea, diabetes and other ailments. Previous research found P. fruticosa leaf extract (C-3) combined with Ginkgo biloba extracts (EGb) showed obvious synergistic effects in a variety of oxidation systems. The aim of the present study was to further confirm the synergy of P. fruticosa combined with EGb viewed from physiological bioavailability and explore the related bioactive mechanism behind the synergism. METHODS: The microbial test system (MTS) was adopted to evaluate the related bioactive mechanism. The synergistic effects were evaluated by isobolographic analysis. The H2O2 production rate and antioxidant enzyme (Catalase (CAT), Peroxidase (POD), Superoxide dismutase (SOD), Glutathione peroxidase (GSH-PX)) activities were determined by the colorimetric method. Enzyme gene (CAT, SOD) expression was measured by real time-PCR. RESULTS: The MTS antioxidant activity results showed the combination of C-3 + EGb exhibited synergistic effects especially at the ratio 5:1. Components of isorhamnetin and caffeic acid in C-3 and EGb displayed strong antioxidant activities on MTS and their combination also showed significant synergy in promoting H2O2 production. The combinations of C-3 + EGb and isorhamnetin + caffeic acid promoted CAT and SOD enzyme activities and the ratio 1:1 exhibited the strongest synergy while no obvious promotion on POD and GSH-PX enzyme activities was found. Both combinations above promoted gene expression of CAT and SOD enzymes and the ratio 1:1 exhibited the strongest synergy. CONCLUSIONS: Antioxidant activity results in MTS further confirmed the significant synergy of C-3 combined with EGb and isorhamnetin combined with caffeic acid. The synergy of C-3 combined with EGb may be attributed to the combination of isorhamnetin + caffeic acid, which promoted CAT and SOD enzyme gene expression and further promoted the enzyme activities in E. coli. This study could further provide rational basis for optimizing the physiological bioavailability of P. fruticosa by using natural and safe antioxidants in low doses to produce new medicines and functional products.

Phenolic Compounds and Antioxidant Activity of Different Organs of Potentilla fruticosa L. from Two Main Production Areas of China.

This report compared the phenolic compounds and antioxidant activity of the leaves, flowers, and stems of Potentilla fruticosa L. collected from two main production areas of P. R. China (Taibai Mountains and the Qinghai Huzhu Northern Mountains). The results indicated that there were significant differences in the phenol contents and antioxidant activities among the different organs and between the two productions. High-performance liquid-chromatography analysis indicated that hyperoside, (+)-catechin, ellagic acid, and rutin were the primary compounds in leaves and flowers; for stems, the content of six phenolic compounds, from two productions, were the lowest. The 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) di-ammonium salt (ABTS), ferric reducing power (FRAP), lipid peroxidation assays, and microbial test system (MTS) were used to evaluate the antioxidant activity. The results demonstrated that the leaves from two productions exhibited powerful antioxidant activity than other organs, which did not significantly differ from that of the positive control (rutin), followed by the flowers and stems. The correlation between the content of phytochemicals and the antioxidant activities of different organs showed that the total phenol, tannin, hyperoside, and (+)-catechin contents may influence the antioxidant activity, and these compounds can be used as markers for the quality control of P. fruticosa.

Chemical Composition and Antioxidant Activity of Essential Oils and Methanol Extracts of Different Parts from Juniperus rigida Siebold & Zucc.

The chemical composition and antioxidant activity of essential oils and MeOH extracts of stems, needles, and berries from Juniperus rigida were studied. The results indicated that the yield of essential oil from stems (2.5%) was higher than from needles (0.8%) and berries (1.0%). The gas chromatography/mass spectrometer (GC/MS) analysis indicated that 21, 17, and 14 compounds were identified from stems, needles, and berries essential oils, respectively. Caryophyllene, α-caryophyllene, and caryophyllene oxide were primary compounds in both stems and needles essential oils. However, α-pinene and ß-myrcene mainly existed in berries essential oils and α-ionone only in needles essential oils. The high-performance liquid chromatography (HPLC) analysis indicated that the phenolic profiles of three parts exhibited significant differences. Needles extracts had the highest content of chlorogenic acid, catechin, podophyllotoxin, and amentoflavone, and for berries extracts, the content of those compounds was the lowest. Meanwhile, three in vitro methods (DPPH, ABTS, and FRAP) were used to evaluate antioxidant activity. Stems essential oil and needles extracts exhibited the powerful antioxidant activity than other parts. This is the first comprehensive study on the different parts of J. rigida. The results suggested that stems and needles of J. rigida are useful supplements for healthy products as new resources.

Elevational patterns of plant richness in the Taibai Mountain, China.

The elevational distribution of plant diversity is a popular issue in ecology and biogeography, and several studies have examined the determinants behind plant diversity patterns. In this study, using published data of the local flora of Taibai Mountain, we explored the effects of spatial and climatic factors on plant species richness. We also evaluated Rapoport's elevational rule by examining the relationship between elevational range size and midpoint. Species richness patterns were regressed against area, middle domain effect (MDE), mean annual temperature (MAT), and mean annual precipitation (MAP). The results showed that richness of overall plants, seed plants, bryophytes, and ferns all showed hump-shaped patterns along the elevational gradient, although the absolute elevation of richness peaks differed in different plant groups. Species richness of each plant group was all associated strongly with MAT and MAP. In addition to climatic factors, overall plants and seed plants were more related to area in linear regression models, while MDE was a powerful explanatory variable for bryophytes. Rapoport's elevational rule on species richness was not supported. Our study suggests that a combined interaction of spatial and climatic factors influences the elevational patterns of plant species richness on Taibai Mountain, China.

Phytochemical profiles and antioxidant and antimicrobial activities of the leaves of Zanthoxylum bungeanum.

The ethanol crude extracts (ECE) and their subfractions from Zanthoxylum bungeanum leaves were prepared and their phytochemical profiles and antioxidant and antimicrobial activities were investigated. Moreover, the effective HPLC procedure for simultaneous quantification of twelve compounds in Z. bungeanum leaves was established. The correlation between the phytochemicals and antioxidant activity was also discussed. The ethyl acetate fraction (EAF) had the highest total phenolic (97.29 mmol GAE/100 g) and flavonoid content (67.93 mmol QE/100 g), while the greatest total alkaloid content (4.39 mmol GAE/100 g) was observed in the chloroform fraction (CF). Twelve compounds were quantified by RP-HPLC assay. EAF exhibited the highest content of quercitrin, kaempferol-3-rhamnoside, quercetin, sesamin, and nitidine chloride (125.21, 54.95, 24.36, 26.24, and 0.20 mg/g); acetone fraction (AF) contained the highest content of chlorogenic acid, rutin, hyperoside, and trifolin (5.87, 29.94, 98.33, and 31.24 mg/g), while kaempferol-3-rhamnoside, xanthyletin, and sesamin were rich in CF. EAF and AF exhibited significant DPPH, ABTS radical scavenging abilities and reducing power (FRAP), whereas CF exhibited significant antifungal activity. Moreover, EAF also showed stronger antibacterial activity. In conclusion, Z. bungeanum leaves have health benefits when consumed and could be served as an accessible source for production of functional food ingredients and medicinal exploration.

Phytochemical profiles, antioxidant and antimicrobial activities of three Potentilla species.

BACKGROUND: Extracts from Potentilla species have been applied in traditional medicine and exhibit antioxidant, hypoglycemic, anti-inflammatory, antitumor and anti-ulcerogenic properties, but little has been known about the diversity of phytochemistry and pharmacology on this genus. This study investigated and compared the phytochemical profiles, antioxidant and antimicrobial activities of leaf extracts from three Potentilla species (Potentilla fruticosa, Potentilla glabra and Potentilla parvifolia) in order to discover new resources for lead structures and pharmaceutical products. METHODS: Chemical composition and content of six phenolic compounds were evaluated and determined by RP-HPLC; Total phenolic and total flavonoid content were determined using Folin-Ciocalteau colourimetric method and sodium borohydride/chloranil-based method (SBC); Antioxidant activities were determined using DPPH, ABTS and FRAP assays; Antimicrobial properties were investigated by agar dilution and mycelial growth rate method. RESULTS: The results showed hyperoside was the predominant phenolic compound in three Potentilla species by RP-HPLC assay, with the content of 8.86 (P. fruticosa), 2.56 (P. glabra) and 2.68 mg/g (P. parvifolia), respectively. The highest content of total identified phenolic compounds (hyperoside, (+)-catechin, caffeic acid, ferulic acid, rutin and ellagic acid) was observed in P. parvifolia (14.17 mg/g), follow by P. fruticosa (10.01 mg/g) and P. glabra (7.01 mg/g). P. fruticosa possessed the highest content of total phenolic (84.93 ± 0.50 mmol gallic acid equivalent/100 g) and total flavonoid (84.14 ± 0.03 mmol quercetin equivalent/100 g), which were in good correlation with its significant DPPHIC50 (16.87 µg/mL), ABTS (2763.48 µmol Trolox equivalent/g) and FRAP (1398.70 µmol Trolox equivalent/g) capacities. Furthermore, the effective methodology to distinguish the different species of Potentilla was also established by chromatographic fingerprint analysis for the first time. The results of antimicrobial activities showed P. fruticosa exhibited the strongest inhibition aganist Gram-positive bacteria, Pseudomonas aeruginosa and Candida albicans with MIC values of 0.78-6.25 mg/mL. P. parvifolia possessed antibacterial and antifungal activities against all the microorganisms tested, with EC50 and MIC values of 20.52-47.02 mg/mL and 0.78-50 mg/mL, respectively. CONCLUSIONS: These results indicated that leaf extracts from three Potentilla species could become useful supplement for pharmaceutical products as a new antioxidant and antimicrobial agents.

Differences in Juniperus przewalskii Rhizosphere Microbiomes across Age Classes: Community Diversity and Assembly.

Evidence shows that biotic and abiotic factors have apparent diversity at different forest ages, leading to changes in rhizosphere microbiomes. However, the difference in diversity, co-occurrence pattern, and assembly of the rhizosphere microbial community among the different forest ages is still unclear. A total of 24 Juniperus przewalskii rhizosphere soil samples were selected from four representative age classes, using diameter at breast height (DBH) as a proxy for tree age (age class I: 5 < DBH ≤ 12.5 cm, age class II: 12.5 < DBH ≤ 22.5 cm, age class III: 22.5 < DBH ≤ 32.5 cm, and age class IV: DBH > 32.5 cm), and analyzed the structural characteristics of the soil microbial community by high-throughput amplicon sequencing. With the increase in age class, the microbial community α-diversity and ß-diversity had an increased trend. The bacterial Shannon index in class II and class III were markedly higher than in class I. From class I to class IV, the relative abundances of dominant phyla such as Actinobacteria and Ascomycota decreased, and the relative abundances of Proteobacteria and Basidiomycota increased in contrast. The complexity and association stability of the bacteria and fungi community network structure increase with forest age. Stochastic processes mediated the assembly of soil bacterial communities, while deterministic processes played a more significant role in the assembly of fungal communities. In addition, the relative importance of deterministic components in the microbial community increased significantly with age class. Random forests suggested that soil pH, plant Shannon-Wiener index (H), and Pielou's evenness index (J) were the most important driving factors of bacterial and fungal community assembly. Overall, these results provide information useful for understanding the generation and maintenance mechanisms of rhizosphere microbial communities across age classes.

Effects of age and tissue of Juniperus sabina L. on its phytochemical characteristics, anti-cholinesterase, antidiabetes, and anti-drug resistant bacteria activities.

Juniperus sabina L. is used in the traditional Chinese medicine (TCM) system to prevent or treat various diseases. However, only the leaves and branches are used as medicinal parts. The aim of this study was to compare the chemical characteristics of different tissues (leaves, branches, stems, and roots) of J. sabina at different ages by HPLC-MS and to evaluate the biological activity (enzyme inhibition, anti-drug-resistant bacteria). Total phenol (TPC) and total lignan (TLC) contents in J. sabina were determined by Folin-Ciocalteu method and UV spectrophotometry, respectively. High levels of total phenols (87.16 mg GAE/g dry weight) and total lignans (491.24 mg PPT/g dry weight) were detected in fifteen annual J. sabina roots and current year leaves, respectively. Eleven compounds, of which six were phenolic compounds and five were lignans, were identified and quantified by HPLC/HPLC-MS. Statistical analysis showed that the distribution and content of the detected compounds showed considerable variation among ages and tissues, and that the current year leaves of fifteen annual J. sabina could be used as a potential application site for the source of podophyllotoxin. Acetylcholinesterase (AChE) inhibitory activity was found to be the highest on the extracts of fifteen annual J. sabina current year leaves (47.37 µg/mL), while the highest inhibition towards butyrylcholinesterase (BChE) was observed for the extracts of seven annual J. sabina previous year leaves (136.3 µg/mL). And the second annual J. sabina current year stem's extracts showed the best antidiabetic activity (anti-α-glucosidase, 62.59 µg/mL). In addition, the extracts of fifteen annual J. sabina roots (47.37 µg/mL) showed the highest anti-MRSA activity (31.25 µg/mL). Redundancy analysis (RDA) was conducted to clarify the factors affecting the biological activity of J. sabina, and its results showed that epicatechin and matairesinol showed positive promotion. This study provides a new perspective for understanding the chemical differences and comprehensive utilization of different tissues of J. sabina.

Chemical composition, chemotypic characterization, and histochemical localization of volatile components in different cultivars of Zanthoxylum bungeanum Maxim. leaves.

Zanthoxylum bungeanum Maxim., an important spice plant, is rich in volatile components and has formed several cultivars in China. Genetic variation among different cultivars has significant effects on volatile components. In this study, a total of 52 volatile compounds were detected from 11 cultivars of Z. bungeanum, among which palmitic acid, (+)-limonene, phytol, ß-caryophyllene, and terpinyl acetate were screened as characteristic compounds, with palmitic acid and phytol contributing the most to the volatile composition. Combined with the results of chemometric and content analyses, three Z. bungeanum chemotypes were identified: (+)-limonene, ß-caryophyllene + terpinyl acetate, and palmitic acid + phytol. In addition, the dynamics of the accumulation of its main components were explored, and the optimal harvest period for Z. bungeanum leaves (late July or early August) was clarified. Moreover, histochemical analysis results showed that terpenoids were mainly accumulated in the oil cells of Z. bungeanum leaves, and there were some differences in the number of oil cells in different chemotypes of Z. bungeanum, which might affect the yield and quality of volatile components. The results showed that the differences of chemical composition among diverse chemotypes of Z. bungeanum might be an important factor leading to the quality differences of the same planting resources. Accordingly, the study on the classification of Z. bungeanum chemotypes and the accumulation patterns of major chemical components is of great theoretical significance and practical value as a favorable guarantee for the development and utilization of Z. bungeanum resources and quality control.

Predicting suitable distribution areas of Juniperus przewalskii in Qinghai Province under climate change scenarios.

Juniperus przewalskii is important for water and soil conservation. It is one of the native tree species suitable for afforestation and greening in high-cold and arid areas of Qinghai Province. Predicting the potential geographic distribution of J. przewalskii in Qinghai Province under the climate change scenario will provide theoretical guidance for its management, introduction, and cultivation. In this study, the current potential distribution of J. przewalskii was simulated firstly based on 88 effective distributional records from field investigation and data collection via Maxent model and ArcGIS spatial analysis. We analyzed dominant factors affecting the potential distribution of J. przewa-lskii by Jackknife test and correlation coefficient. The distribution of J. przewalskii under three climate change scenarios (SSP126, SSP245, SSP585) with the climate model data of the sixth phase of the Coupled Model Intercomparison Projects (CMIP6) were predicted for 2061-2080. The results showed that the area under the receiver operating characteristic curve (AUC) of the Maxent model was greater than 0.92, suggesting a good predictive performance. Under current climatic condition, the suitable distribution area of J. przewalskii was mainly located in the eastern part of Qinghai Province, with the suitable area accounted for 11.2% of the total. The dominant factors affecting the distribution of J. przewalskii were altitude, annual precipitation, the minimum temperature of coldest month, and slope, with a cumulative contribution rate of 85.9%. The suitable areas of J. przewalskii altered under the three future climate scenarios. The suitable areas would shrink under the SSP245 scenario and expand under the SSP126 and SSP585 scenarios. The sui-table area of J. przewalskii would have the most obvious expansion under the SSP126 climate situation, with the expanding areas being mainly located in Zeku County, the north-central part of Henan Mongolian Autonomous County, and the southeast of Qilian County. Under three climatic scenarios, the suitable area of J. przewalskii would gradually migrate to high altitudes, but without clear altitudinal and longitudinal shifts.

Quality evaluation of different varieties of Zanthoxylum bungeanum Maxim. peels based on phenolic profiles, bioactivity, and HPLC fingerprint.

This work aims to evaluate the quality of seven varieties of Zanthoxylum bungeanum peels based on phenolic compounds, bioactivity, and HPLC fingerprint combined with chemometrics analysis, and pick out the key chemical compounds. As a result, S2 (Fengxian Dahongpao) showed the highest content of total phenolic and rutin, as well as the strongest antioxidant activity, followed by S6 (Hancheng Shizitou). From HPLC fingerprint, eight common characteristic peaks were selected and proved to be effective in controlling the quality of Z. bungeanum peels with the total contribution of 92.775%. The similarity values of each sample ranged between 0.696 and 0.970. In addition, hyperoside was identified as another key chemical indicator for quality evaluation of Z. bungeanum peels by PCA. Accordingly, seven varieties of Z. bungeanum were classified into four groups, among which group 4 (Fengxian Dahongpao, S2) was considered as an outstanding variety, followed by group 1 (S5, S6, and S7) and group 3 (S3 and S4), and group 2 (Fugu late-maturing, S1) was the last one. These results will be helpful to establish an effective and comprehensive evaluation system of Z. bungeanum. PRACTICAL APPLICATION: This study not only provides another index for quality evaluation of Z. bungeanum peels, but it also expects to be a theoretical basis for high-quality germplasm cultivation and the development of Z. bungeanum peels as food additives, pharmaceutical, or health care products.