Prioritization of the Secondary Metabolites for the Rapid Annotation Based on Liquid Chromatography-High Resolution Mass Spectrometry Assessment: Varanasine and Schroffanone from Murraya paniculata and Cytotoxic Evaluation.

The liquid chromatography-high resolution mass spectrometry (LC-HRMS) technique enables the detection of phytochemicals present in the extracts. LC-HRMS-generated mass list showed abundant compounds of interest, artifacts, and primary metabolites. The identification of a secondary metabolite of interest within the extract is very challenging. We hypothesized that identifying the "new metabolite" in the whole metabolome is more challenging than identifying it within the class of metabolites. The proposed prioritization strategy focused on the elimination of unknown and prioritizing the known class of secondary metabolites to identify new metabolites. The prioritization strategy demonstrated on Murraya paniculata for the identification of new metabolites. LC-HRMS-generated information is used as a filter to target the secondary metabolite and the new metabolites. This strategy successfully annotated the new coumarin and coumarin alkaloids from the mass list of 1448 metabolites. Varanasine (3), schroffanone (4), schroffanene (5), and O-methylmurraol (9) are new compounds, and coumarin (1, 2, and 6-8) are known. Varanasine (3) is the first naturally occurring 7-aminocoumarin with additional N-formyl functionality. The isolates were screened for cytotoxicity against the panel of cancer cell lines. Varanasine (3) and minumicrollin (6) showed significant cytotoxicity and apoptosis-inducing potential. The immunoblot analysis confirmed inhibition of apoptotic protein PARP-1 and caspase-3 expression by 3 and 6.

Natural Infection of Murraya paniculata and Murraya sumatrana with 'Candidatus Liberibacter asiaticus' in Java.

The phloem-limited bacterium 'Candidatus Liberibacter asiaticus' (CLas) is the putative causal pathogen of the severe Asiatic form of huanglongbing (citrus greening) and is most commonly transmitted by the Asiatic citrus psyllid Diaphorina citri. CLas severely affects many Citrus species and hybrids and has been recorded in the Citrus relative, orange jasmine, Murraya paniculata (L.) Jack (syn. M. exotica L.). In this study, 13 accessions of three Murraya species (M. paniculata, M. sumatrana Roxb., and M. lucida [G.Forst.] Mabb.) and the Papuan form of a putative hybrid (M. omphalocarpa Hayata) were identified morphologically and molecularly based on sequence identity of the matK-5'trnK region of the chloroplast genome, and infection on these plants under field conditions was determined by PCR and quantitative real-time PCR (qPCR) on two to four occasions over 14 months. CLas was repeatedly detected in leaflet midribs by PCR and qPCR on four and three accessions of M. paniculata and M. sumatrana, respectively. It was not detected in leaflet midribs of single accessions of M. lucida and M. omphalocarpa. The species identification of the CLas-positive accessions was further confirmed using all the molecular taxonomic markers consisting of the six fragments of the maternally inherited chloroplast genome and part of the nuclear-encoded internal transcribed spacer (ITS) region. The results indicated that natural infection of M. paniculata and M. sumatrana with CLas can occur in Java. To our knowledge, this is the first demonstration of the natural infection of M. sumatrana with CLas. Further studies are required to determine whether infections persist in the absence of D. citri.

A comprehensive review of the botany, phytochemistry, pharmacology, and toxicology of Murrayae Folium et Cacumen.

Ethnopharmacological relevance: Murrayae Folium et Cacumen (MFC) is a plant considered to be a traditional Chinese medicine with culinary value as well. The dry leaves and twigs of Murraya paniculata and M. exotica are used to treat stomach aches, rheumatism, toothaches, swelling, and insect and snake bites. They are also used to prepare spicy chicken dishes. Aim of the review: This review comprehensively summarizes the available information on the botanical characterization, phytochemistry, pharmacological activities, pharmacodynamics, pharmacokinetics, and toxicity of MFC. Methods: Relevant scientific literature up to August 2023 was included in the study. Chinese and English studies on MFC were collected from databases, including PubMed, Elsevier, Web of Science, Springer, Science Direct, Wiley, ACS, and CNKI (Chinese). Doctoral and Master's dissertations were also included. Results: In total, 720 compounds have been identified and reported in the literature, including flavonoids, coumarins, alkaloids, sterols, phenylpropenols, organic acids, spirocyclopentenones, and volatile oils. Flavonoids and coumarins are the two most important bioactive compounds responsible for these pharmacological activities. MFC has anti-inflammatory, anti-bacterial, anti-microbial, anti-diabetic, anti-tumor, anti-oxidant, anti-depressant, potential anti-Alzheimer's disease, chondroprotective, and analgesic properties. The pharmacological effects include interrupting the STAT3/NF-κB/COX-2 and EGFR signaling pathways, downregulating EpCAM expression, inhibiting NF-κB and ERK signals, inhibiting the EP/cAMP/PKA signaling pathway and miR-29a/Wnt/ß-catenin signaling activity, and upregulating Foxo3a expression. Conclusion: This review demonstrates that the chemical constituents, pharmacological activities, pharmacodynamics, pharmacokinetics, and toxicity of MFC support its use in traditional Chinese botanical medicines. MFC contains a wide range of chemical compounds. Flavonoids and coumarins promote strong pharmacological activity and, are low-toxicity natural phytomedicines that are widely used in medicine, food, ornamentation, and cosmetics, making MFC a promising compound for development and use in the treatment of several medical conditions.

A quantitative chemomics strategy for the comprehensive comparison of Murraya paniculata and M. exotica using liquid chromatography coupled with mass spectrometry.

Murrayae Folium et Cacumen (MFC) is a traditional Chinese medicine (TCM) derived from two plant species, Murraya exotica L. and Murraya paniculata (L.) Jack, as recorded in the Chinese Pharmacopoeia. However, there is no research available on the comprehensive analysis and comparison of the chemical constituents of these two species. In the present study, an integrated LC-MS-based quantitative metabolome strategy was proposed to conduct a comprehensive and in-depth qualitative and quantitative analysis and comparison of the chemome of M. exotica and M. paniculata. Firstly, the universal chemical information of two plants was obtained by quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) combined with hybrid triple quadrupole-linear ion trap mass spectrometry (Qtrap-MS). Subsequently, a UNIFI in house database, the proposed fragmentation patterns, and a quantitative structure chromatographic retention relationship (QSRR) model were integrated for the rapid, comprehensive, and accurate structural elucidation of the chemical constituents of these two species. Thirdly, a large-scale quantitation method was established using scheduled multiple reaction monitoring mode (sMRM) and 76 primary components were selected as quantitative markers for the method validation. The obtained dataset was then subjected for multivariate statistical analysis to comprehensive comparison of these two plants. As a result, a total of 209 and 212 compounds were identified from M. exotica and M. paniculata, respectively. Among them, 103 common constituents were disclosed in both plants. The multivariate statistical analysis and absolute quantitative analysis revealed noticeable differences in the contents of specific chemical constituents between these two plants. The higher quantity constituents in M. exotica are 7-methoxycoumarins, while polymethoxylated flavonoids are the major constituents in M. paniculata. The common compounds accounted for approximately 80 % of the quantitative components in both plants, which provides a theoretical basis for their common use as the official source of MFC. In sum, the established quantitative chemomics strategy supplies an effective means for comprehensive chemical comparison of multi-source TCMs.

Demethoxymurrapanine, an indole-naphthoquinone alkaloid, inhibits the proliferation of oral cancer cells without major side effects on normal cells.

Antioral cancer drugs need a greater antiproliferative impact on cancer than on normal cells. Demethoxymurrapanine (DEMU) inhibits proliferation in several cancer cells, but an in-depth investigation was necessary. This study evaluated the proliferation-modulating effects of DEMU, focusing on oral cancer and normal cells. DEMU (0, 2, 3, and 4 µg/mL) at 48 h treatments inhibited the proliferation of oral cancer cells (the cell viability (%) for Ca9-22 cells was 100.0 ± 2.2, 75.4 ± 5.6, 26.0 ± 3.8, and 15.4 ± 1.4, and for CAL 27 cells was 100.0 ± 9.4, 77.2 ± 5.9, 57.4 ± 10.7, and 27.1 ± 1.1) more strongly than that of normal cells (the cell viability (%) for S-G cells was 100.0 ± 6.6, 91.0 ± 4.6, 95.0 ± 2.6, and 95.8 ± 5.5), although this was blocked by the antioxidant N-acetylcysteine. The presence of oxidative stress was evidenced by the increase of reactive oxygen species and mitochondrial superoxide and the downregulation of the cellular antioxidant glutathione in oral cancer cells, but these changes were minor in normal cells. DEMU also caused greater induction of the subG1 phase, extrinsic and intrinsic apoptosis (annexin V and caspases 3, 8, and 9), and DNA damage (γH2AX and 8-hydroxy-2-deoxyguanosine) in oral cancer than in normal cells. N-acetylcysteine attenuated all these DEMU-induced changes. Together, these data demonstrate the preferential antiproliferative function of DEMU in oral cancer cells, with the preferential induction of oxidative stress, apoptosis, and DNA damage in these cancer cells, and low cytotoxicity toward normal cells.

A Rapid PCR-RFLP Method for Assessing Heterozygosity of Murraya paniculata Germplasm / 中国实验方剂学杂志

ObjectiveTo establish a rapid method for evaluating the heterozygosity of Murraya paniculata germplasm materials and provide as a foundation for developing germplasm breeding and innovation measures for M. paniculata. MethodSingle nucleotide polymorphisms （SNPs） were screened from the genome resequencing data of 65 plants of M. paniculata. A self-written script was used to transform 20 SNPs into restriction fragment length polymorphism （RFLP） markers. Polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） was employed to detect the 20 RFLP markers in 12 M. paniculata germplasm accessions， and the heterozygosity of M. paniculata germplasm accessions was calculated based on the number of enzyme-cutting bands at the 20 RFLP marker sites. Plink was used to calculate the whole genome heterozygosity of 12 M. paniculata germplasm accessions， and the results obtained with different methods were compared. ResultThere was no significant difference in the heterozygosity calculated by the PCR-RFLP method and the genome resequencing method. The PCR-RFLP and genome resequencing methods identified 8 and 9 germplasm accessions， respectively， with a heterozygosity level less than 30%. Seven germplasm accessions with heterozygosity less than 30.00% were calculated by both methods. ConclusionThe PCR-RFLP method established in this study for evaluating the heterozygosity of M. paniculata germplasm demonstrates the precision of 87.5% and the accuracy of 77.8%. This method serves as a reference for developing heterozygosity evaluation methods in other medicinal plant germplasm resources.

Anticholinesterases activity of Murraya koenigii (L.) Spreng. and Murraya paniculata (L.) Jacq. essential oils with GC/MS analysis and molecular docking.

GC/MS analysis of Murraya koenigii (L.) Spreng. and Murraya paniculata (L.) Jacq. leaves revealed the identification of 73 components, with an evident greater contribution of monoterpenes hydrocarbons to their total volatiles. α-Pinene (37.5%) and ß-caryophyllene (27.4%) were the most abundant compounds in M. koenigii leaves and ß-phellandrene (40.7%) in M. paniculata leaves, using headspace. ß-Phellandrene (33.7%) was the major constituent by M. koenigii leaves where germacrene D (23.8%), and δ-elemene (22.0%) were predominant in M. paniculata leaves, using steam distillation. M. koenigii leaves oil showed quite remarkable cholinesterase inhibitory activity, where oil of M. paniculata leaves showed strong inhibitory activity against AChE (IC50=13.2 ± 0.9 µg/mL) and BChE (IC50=5.1 ± 0.3 µg/mL). Germacrene D, α-zingiberene, and δ-elemene showed higher affinity to BChE than AChE as revealed from docking scores (S = -5.65 to -6.03 Kcal/mol) for BChE and (S = -5.56 to -6.25 Kcal/mol) for AChE.

Chromosome-level genome assembly of Murraya paniculata sheds light on biosynthesis of floral volatiles.

BACKGROUND: Murraya paniculata (L.) Jack, commonly called orange jessamine in the family Rutaceae, is an important ornamental plant in tropical and subtropical regions which is famous for its strong fragrance. Although genome assemblies have been reported for many Rutaceae species, mainly in the genus Citrus, full genomic information has not been reported for M. paniculata, which is a prerequisite for in-depth genetic studies on Murraya and manipulation using genetic engineering techniques. Here, we report a high-quality chromosome-level genome assembly of M. paniculata and aim to provide insights on the molecular mechanisms of flower volatile biosynthesis. RESULTS: The genome assembly with a contig N50 of 18.25 Mb consists of 9 pseudomolecules and has a total length of 216.86 Mb. Phylogenetic analysis revealed that M. paniculata diverged from the common ancestor approximately 25 million years ago and has not undergone any species-specific whole genome duplication events. Genome structural annotation and comparative genomics analysis revealed that there are obvious differences in transposon contents among the genomes of M. paniculata and Citrus species, especially in the upstream regions of genes. Research on the flower volatiles of M. paniculata and C. maxima at three flowering stages revealed significant differences in volatile composition with the flowers of C. maxima lacking benzaldehyde and phenylacetaldehyde. Notably, there are transposons inserted in the upstream region of the phenylacetaldehyde synthase (PAAS) genes Cg1g029630 and Cg1g029640 in C. maxima, but not in the upstream region of three PAAS genes Me2G_2379, Me2G_2381, and Me2G_2382 in M. paniculata. Our results indicated that compared to the low expression levels of PAAS genes in C. maxima, the higher expression levels of the three PAAS genes in M. paniculata are the main factor affecting the phenylacetaldehyde biosynthesis and causing the content difference of phenylacetaldehyde. The phenylacetaldehyde synthetic activities of the enzymes encoded by M. paniculata PAAS genes were validated by in vitro analyses. CONCLUSIONS: Our study provides useful genomic resources of M. paniculata for further research on Rutaceae plants, identifies new PAAS genes, and provides insights into how transposons contribute to variations in flower volatiles among Murraya and Citrus plants.

A Brief Review on Murraya paniculata (Orange Jasmine): pharmacognosy, phytochemistry and ethanomedicinal uses.

Objectives: Murraya paniculata (family-Rutaceae), popularly known as orange jasmine, is the most important evergreen plant. The Rutaceae family is economically significant due to its diverse edible fruits and essential oils. Methods: Murraya paniculata extracts (MPE) of leaf have been shown to include phenolic compounds, highly oxygenated flavonoids, flavanones, sesquiterpenoids, polymethoxy glycosides, and coumarins. Cyclocitral, methyl salicylate, trans-nerolidol, cubenol, isogermacrene, -cadinol, and cubeb-11-ene are all abundant in MPE. The usages of various parts of this plant, such as bark, leaves and flower, as a remedy for a variety of ailments as widely recorded in the traditional literature. The plant has anti-diabetic, anti-obesity, antibacterial, anti-implantation, anti-oxidative, cytotoxic, anti-diarrheal, antidepressant and anti-anxiety properties and many others. Results: The goal of the review is to reignite interest in this potential plant, encouraging researchers to continue their research in order to uncover novel therapeutic compounds for the treatment and management of a range of infections. The current review provided a comprehensive overview of this traditional unique plant. Conclusion: The review paves a way for exploring its active chemical elements with substantial pharmacological values further for potential benefits of mankind.

Antimicrobial activities and phytochemicals of Murraya paniculata L. flowers, leaves and bark crude extracts

Aims@#Murraya paniculata (L.) has been widely employed in medicine, has also been modified to serve as an ingredient in health foods and found application in cosmetics. This study was aimed to assess the biological activities of M. paniculata by analyzing the chemical compositions of its flowers, leaves and bark.@*Methodology and results@#Crude extracts drawn from the flowers, leaves and bark of M. paniculata underwent testing to determine the antibacterial properties in terms of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), as well as the overall chemical composition, total phenolic content, flavonoids and antioxidant activity. Crude extract of leaves exhibited the most potent antibacterial activity when tested against Staphylococcus aureus TISTR 1466, Bacillus subtilis ATCC 6633 and Pseudomonas aeruginosa ATCC 27853. The crude extract from bark delivered the most significant antibacterial activity when tested against Micrococcus luteus TISTR 9341, Escherichia coli ATCC 1261, Pseudomonas sp., Streptococcus sp. and Methicilin resistant S. aureus (MRSA). For all crude extracts, the MIC value against M. luteus TISTR 9341 was 12.5 mg/mL. Meanwhile, the MBC value for the crude extract of leaves against B. subtilis ATCC 6633 was 12.5 mg/mL, whereas, for flower and bark crude extracts, the MBC value against S. aureus TISTR 1466 was 25 mg/mL. Antioxidant activity was at its highest for the crude extract from bark (IC50 = 1.36 mg/mL). The highest phenolic content was recorded for the crude extract from bark, while the highest flavonoid content came from the crude extract of leaves (70.81 ± 0.31 mgGAE/g extract and 115.73 ± 1.18 mgQE/g extract, respectively).@*Conclusion, significance and impact of study@#The research findings suggest that the crude extracts of M. paniculata leaves and bark show greater significant levels of bioactivity than was the case for crude extracts from flowers. The research findings could help in exploring the possibilities of using M. paniculata for pharmaceutical purposes and in aquaculture.

Diversity in Phytochemical Composition and Medicinal Value of Murraya paniculata.

Murraya paniculata is herbal medicinal plant which is traditionally being used for management of cardiovascular, intestinal and respiratory (air way) disorders. This evergreen plant of tropical regions is a member of Rutaceace family. The goal of this review is to analyze and report the biological activities and active phytochemicals reported from Murraya paniculata (M. paniculata) extracts and essential oil. The data was searched using different search engines and using specific key words including M. paniculata, herbal medicine, phytochemicals, extract, essential oil, pharmacological activities. M. paniculata has been found to have wide range of pharmacological activities, including antinociceptive, antianxiety, antioxidant, antidepressant, antibacterial, analgesic and anti-diabetic properties. A diverse range of phytochemicals, including phenols, coumarins, terpenoids, flavonoids, and alkaloids have been isolated from various portions of the plant and tested for a variety of biological activities. This review will provide more information and stimulate additional research to develop more effective and cost-efficient alternative medicine from this plant.

Identification of Murrayae Folium et Cacumen by Multiplex Allele-Specific PCR / 中国实验方剂学杂志

ObjectiveTo establish a polymerase chain reaction（PCR） method to accurately discriminate the crude materials of Murrayae Folium et Cacumen， Murraya exotica and M. paniculata. MethodBased on the difference in chloroplast genome sequences of M. exotica and M. paniculata， species-specific identification primers P03 and P04 of M. exotica and M. paniculata were designed according to single nucleotide polymorphism （SNP） on the chloroplast genome. A multiplex allele-specific PCR identification method was established for the identification of M. exotica and M. paniculata following the optimization of annealing temperature， number of cycles， and primer concentration ratio. The established PCR method for identification was explored and verified in terms of tolerance and feasibility by investigating the type of Taq polymerases and PCR system model. ResultIn this multiplex allele-specific PCR identification method， about 330 and 230 bp of specific fragments were amplified from DNA templates of M. exotica and M. paniculata， respectively， under the following conditions：cycle number of 31， annealing temperature of 60 ℃， and primer concentration ratio of P03 and P04 of 1∶2. Consistent results were obtained for samples from different sources. ConclusionThe multiplex allele-specific PCR identification method established in this study can accurately identify the origin of Murrayae Folium et Cacumen， which can be used for the simultaneous identification of M. exotica and M. paniculata by the length of fragments in a single identification assay.

Chemical composition, antimicrobial activity and cytotoxicity of Murraya paniculata (L.) Jack leaf essential oil from Assam, India: the effect of oil on cellular morphology of micro-organisms.

Murraya paniculata (L.) Jack is commonly cultivated as ornamental plant in Assam and has been used as spice and phytomedicine traditionally for many healthcare purposes. The therapeutic potential and chemical constituents of the essential oil of M. paniculata leaf was investigated against several pathogenic microbial species and human cancer cell lines. 29 chemical compounds were identified by GC-MS analysis from the essential oil representing 97.62% of the oil. The major compound identified was caryophyllene (20.93%). Leaf essential oil exhibited promising antibacterial activity against Mycobacterium smegmatis (MIC = 4 µg/mL) and Pseudomonas aeruginosa (MIC = 4 µg/mL). Best anticancer activity of the oil was observed for HeLa cells (IC50 = 6.28 µg/mL). Further, scanning electron microscopic studies revealed that the oil kills micro-organisms with the deformation of cellular morphology on treatment of the oil. Thus, the essential oil of M. paniculata leaf can be an excellent alternative for development of new antimicrobials and anticancer chemotherapeutic agents for the pharmaceutical industries.

Comparison of Murraya exotica and Murraya paniculata by fingerprint analysis coupled with chemometrics and network pharmacology methods.

There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen (MFC) in Chinese Pharmacopoeia, i.e. Murraya exotica L. and M. paniculata (L.) Jack. Herein, a chemical comparison of M. exotica and M. paniculata by high performance liquid chromatography (HPLC) fingerprint analysis coupled with chemometrics and network pharmacology was performed. The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS) and authenticated by references. The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis (HCA) and principal component analysis (PCA), and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis (OPLS-DA). However, the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways, indicating the possibly similar pharmacological effects and mechanisms for M. exotica and M. paniculata. The above results provide valuable evidence for the equivalent use of these two plants in clinical settings. Moreover, the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.

Comparison of the preventive effects of Murraya exotica and Murraya paniculata on alcohol-induced gastric lesions by pharmacodynamics and metabolomics.

ETHNOPHARMACOLOGICAL RELEVANCE: Multi-source phenomenon is very common for traditional Chinese medicine (TCM). Both Murraya exotica L. (ME) and Murraya paniculata (L.) Jack (MP) are used as the source plants of Murrayae Folium et Cacumen (MFC), a traditional Chinese medicine recorded in Chinese Pharmacopoeia for promoting qi and relieving pain, mainly for the treatment of stomach pain, rheumatism and arthralgia. However, up to now, there has been no comparative study of these two plants on their efficacies and mechanisms, thus, further research is needed to evaluate their similarity and difference in order to judge the reasonability for their common usage. AIM OF THE STUDY: This study aims to compare the effects and potential mechanisms of ME and MP, the two source plants of MFC on gastric lesions in rats by pharmacodynamics and metabolomics. MATERIALS AND METHODS: A rat model of gastric lesions induced by 70% aqueous ethanol and 150 mmol/L HCl was established and adopted to evaluate the gastric protective effects of ME and MP by analysis of the lesion index, histopathological changes (observed by H&E staining and TUNEL staining) and cytokine levels (IL-1ß, IL-6, TNF-α, MTL, and GAS). The potential mechanisms were investigated by LC-MS metabolomic analysis of the rat plasma. RESULTS: ME and MP showed the similar effects on improving the lesions of rat stomachs and reducing the cytokine levels related to inflammation and digestion of rats. The metabolomics results showed that the metabolism of rats with gastric lesions was abnormal mainly in lipid metabolism, energy metabolism, and amino acid metabolism. ME and MP demonstrated a similar metabolic modulation for gastric lesions by acting on the similar pathways and metabolites. Also, PLA2 pathway was proved as an important pathway for ME and MP modulation of glycerophospholipid metabolism in gastric lesions. CONCLUSIONS: Our results proved that it is feasible and reasonable to use both of ME and MP as the source plants of MFC, at least for the treatment of gastric lesions, due to their similar pharmacodynamics and metabolic modulation ability. Moreover, the combination of pharmacodynamics and metabolomics is an efficient means for multi-source TCM study.

Early Population Dynamics of "Candidatus Liberibacter asiaticus" in Susceptible and Resistant Genotypes After Inoculation With Infected Diaphorina citri Feeding on Young Shoots.

Huanglongbing is a highly destructive citrus disease associated with "Candidatus Liberibacter asiaticus" (Las), a phloem-limited and non-culturable bacterium, naturally transmitted by the psyllid Diaphorina citri. Although diverse approaches have been used to understand the molecular mechanisms involved in the pathogen-host interaction, such approaches have focused on already infected and/or symptomatic plants, missing early events in the initial days post-inoculation. This study aimed to identify the time course of Las multiplication and whole-plant colonization immediately following inoculation by infected psyllids feeding for 2 days. Thus, the experimental approach was to track Las titers after psyllid inoculation in new shoots (NS) of Citrus × sinensis (susceptible), Murraya paniculata (partially resistant), and Bergera koenigii (fully resistant). Soon after psyllid removal, Las titers dropped until the 10-12th days in all three species. Following this, Las titers increased exponentially only in C. × sinensis and M. paniculata, indicating active bacterial multiplication. In C. × sinensis, Las reached a stationary phase at ∼5 log Las cells/g of tissue from the 40th day onward, while in M. paniculata, Las increased at a lower rate of up to ∼3 log Las cells/g of tissue between the 40th and 60th days, decreasing gradually thereafter and becoming undetectable from the 160th day onward. In B. koenigii, Las titers decreased from the start and remained undetectable. In C. × sinensis, an average of 2.6 log of Las cells/g of tissue was necessary for Las to move out of 50% of the NS in 23.6 days and to colonize the rest of the plant, causing a successful infection. Conversely, the probability of Las moving out of the NS remained below 50% in M. paniculata and zero in B. koenigii. To our knowledge, this is the first study on Las dynamics and whole-plant colonization during the earliest stages of infection. Identification of critical time-points for either successful multiplication or Las resistance may help to elucidate initial events of Las-host interactions that may be missed due to longer sampling intervals and at later stages of infection.

Pest categorisation of Diaphorina citri.

The EFSA Panel on Plant Health performed a pest categorisation of Diaphorina citri (Hemiptera: Liviidae) (Asian citrus psyllid) for the EU. D. citri is a key pest of citrus in several countries as it is a vector of serious bacterial pathogens, the putative causal agents of Huanglongbing (HLB) also known as citrus greening. Eggs are laid on tips of growing shoots on and between unfurling leaves. Females may lay more than 800 eggs during their lives. Nymphs pass through five instars. The life cycle requires from 14 to 49 days, depending upon the season. There is no diapause, but populations are low in winter. It overwinters as an adult which may live for several months. The species completes 9-10 generations/year; however, under protected conditions, up to 16 generations have been recorded. Commission Implementing Regulation (EU) 2019/2072 (Annex IIA) regulates D. citri, as a quarantine pest not known to occur in the EU territory. Fruits and plants for planting provide potential pathways for entry into the EU. Climatic conditions and the availability of host plants provide conditions to support establishment in the EU. The introduction of D. citri would have an economic impact in the EU through direct but mainly indirect effects due to potential transmission of HLB. Phytosanitary measures are available to reduce the likelihood of entry. D. citri satisfies the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. D. citri does not meet the criteria of occurring in the EU, nor plants for planting being the principal means of spread, for it to be regarded as a potential Union regulated non-quarantine pest.

Quantitative Classification of Murraya paniculata Leaf Traits and Endogenous Hormone Contents Analysis / 中国实验方剂学杂志

Objective:To carry out germplasm resource evaluation and new variety breeding of <italic>Murraya paniculata</italic> and improve the germplasm quality， so as to ensure the demand， yield and quality of medicinal materials. Method:Following resource investigation and collection， 17 traits of 107 <italic>M. paniculata</italic> germplasm samples， like plant type， basal diameter， leaf shape， leaf length， and leaf width were determined and then subjected to principal component analysis and factor analysis for screening the principal component factors. Nine primary traits were selected as variables for further cluster analysis using Ward's method and Euclidean distance. According to the characteristics of medicinal parts， the core germplasms were screened out. Then the contents of auxin， zeatin， zeatin nucleoside， isopentenyl adenine， isopentenyl adenine riboside， dihydrozeatin， and dihydrozeatinriboside in the leaves were measured by ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）， followed by their correlation analysis with agronomic trait. Result:The variation coefficients of petiole length， branching number， and basal diameter were large. The nine main factors could be classified into four categories， with a contribution rate of 72.822%. The cluster analysis with Ward's method and Euclidean distance showed that 107 germplasm samples were clustered into six clusters and 61 core germplasms were identified. Such traits as leaf length， leaf width， petiole length， leaf surface， and petiole color were found to play an important role in the classification of <italic>M. paniculata</italic> germplasms. The content of zeatin nucleoside exhibited significant positive correlations with leaf length （<italic>P</italic><0.01）， petiole length （<italic>P</italic><0.01）， and leaf width （<italic>P</italic><0.05）. Conclusion:These results have laid the foundation for further selection and breeding of <italic>M. paniculata</italic> new varieties.

Comparison of Murraya exotica and Murraya paniculata by fingerprint analysis coupled with chemometrics and network pharmacology methods / 中国天然药物

There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen (MFC) in Chinese Pharmacopoeia, i.e. Murraya exotica L. and M. paniculata (L.) Jack. Herein, a chemical comparison of M. exotica and M. paniculata by high performance liquid chromatography (HPLC) fingerprint analysis coupled with chemometrics and network pharmacology was performed. The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS) and authenticated by references. The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis (HCA) and principal component analysis (PCA), and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis (OPLS-DA). However, the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways, indicating the possibly similar pharmacological effects and mechanisms for M. exotica and M. paniculata. The above results provide valuable evidence for the equivalent use of these two plants in clinical settings. Moreover, the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.

Complete chloroplast genome sequence of Murraya paniculata (Rutaceae): a widely used folk medicinal herb.

Murraya paniculate, is traditionally used for management of gut, air way and cardiovascular disorders. In this study, we sequenced the complete chloroplast genome of M. paniculata based on next-generation sequencing and used the data to assess genomic resources. The chloroplast genome of M. paniculata is 160,280 bp in length consisting of large and small single-copy regions of length 87,605 and 18,609 bp, separated by two IR regions of 27,033 bp. The overall GC content was 38.61%. De novo assembly and annotation showed the presence of unique genes with 85 protein-coding genes, 29 tRNA genes, and eight rRNA genes. A maximum-likelihood phylogenomic analysis showed that M. paniculata was closely related to M. caloxylon.