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Ethylene is a signalling factor that plays a key role in the response of plants to abiotic stresses, such as cold stress. Recent studies have shown that the exogenous application of 1-aminocyclopropane-1-carboxylate (ACC), an ethylene promoter, affects plant cold tolerance. The cold-responsive specific gene DREB plays a crucial role in enhancing cold tolerance in plants by activating several cold-responsive (COR) genes. However, how the ethylene biosynthesis pathway regulates this gene in the cold response of thermophilic plants has yet to be fully elucidated. In this study, the thermophilic plant Plumbago indica L. was used as an example. Physiological experiments and transcriptomic analyses revealed that cold stress treatment induced the synthesis of endogenous ACC and regulated the ethylene signalling activator PiERF1, and cold signalling also activated PiDREB1A. Spray experiments also revealed that ACC-induced upregulation of the PiERF1 gene reduced the cold tolerance of P. indica and decreased the expression level of the PiDREB1A gene. These results indicate that ethylene signalling directly regulates the downstream gene PiERF1 and initiates the DREB‒COR cold-responsive signalling pathway to regulate cold tolerance, resulting in the negative regulation of cold tolerance in thermophilic plants. [ABSTRACT FROM AUTHOR]

In 2021, Plumbago indica plants with necrotic spots on their leaves were observed in Beijing, China. Through high-throughput sequencing, we discovered a putative novel member of the genus Cytorhabdovirus, which was provisionally named "plumbago necrotic spot-associated virus" (PNSaV). The full-length negative-sense single-stranded RNA genome of this virus is 13,180 nucleotides in length and contains eight putative open reading frames (ORFs), in the order 3′ leader-N-(P′)-P-P3-M-G-P6-L-5′ trailer. Phylogenetic analysis and pairwise comparisons suggested that PNSaV is most closely related to pastinaca cytorhabdovirus 1, with 59.2% nucleotide sequence identity in the complete genome and 56.4% amino acid sequence identity in the L protein. These findings suggest that PNSaV should be considered a new member of the genus Cytorhabdovirus. [ABSTRACT FROM AUTHOR]

The genus Plumbago (family Plumbaginaceae), commonly known as leadwort, is a sub-tropical shrub that produces secondary metabolite plumbagin, which is employed by pharmaceutical companies and in clinical research. Plumbagin is a potent pharmaceutical because of its anti-microbial, anti-malarial, antifungal, anti-inflammatory, anti-carcinogenic, anti-fertility, anti-plasmodium, antioxidant, anti-diabetic, and other effects. This review documents the biotechnological innovations used to produce plumbagin. The use of modern biotechnological techniques can lead to a variety of benefits, including better yield, increased extraction efficiency, mass production of plantlets, genetic stability, increased biomass, and more. Large-scale in vitro propagation is necessary to minimize over-exploitation of the natural population and allow the use of various biotechnological techniques to improve the plant species and secondary metabolite production. During in vitro culture, optimum conditions are requisites for explant inoculation and plant regeneration. In this review, we provide information on various aspects of plumbagin, depicting its structure, biosynthesis, and biotechnological aspects (both conventional and advanced) along with the future prospects. Key Points: • Critical assessment on in vitro biotechnology in Plumbago species • In vitro propagation of Plumbago and elicitation of plumbagin • Biosynthesis and sustainable production of plumbagin [ABSTRACT FROM AUTHOR]

Metabolite stuffing may depend upon the session of the collection, soil condition, and geographical regions of the collection site, and this impacts the quantitative production and biological potential of the plant species. A total of 14 accessions of Plumbago zeylanica were collected from different locations in Central India to cover the entire range of topography from the foothills up to the highest peak. The instrumental thin-layer chromatography‒ultraviolet detection (instrumental TLC‒UV) method was used to quantify plumbagin and unweighted pair group method with arithmetic mean (UPGMA) cluster analysis to identify elite sources. The present investigation aims to identify the best quality planting material of P. zeylanica, in terms of elite chemotypes collected from different locations of Central India. UPGMA cluster analysis revealed the variation of the plumbagin content (0.0038‒0.6091% dry weight basis) among the collected accessions of P. zeylanica. The cluster analysis of plumbagin content depicted the distinctness in plant metabolite contents between the individuals as they were clustered by difference between accessions. This study will also promote the use of P. zeylanica in herbal drug development and will aid in the site-specific exploration of elite chemotype(s) with validated pharmacological action to meet the medicinal and commercial demands. [ABSTRACT FROM AUTHOR]

Plumbago zeylanica L. is commonly known as chitrak, consumed since long time owing to its potent medicinal benefits. It is a major source of the yellow crystalline naphthoquinone called plumbagin, which is highly acclaimed for its anticancerous activities on different cancers i.e. prostrate, breast, ovarian, etc. The growing urges for this compound make this plant extremely demanding in the global market; hence, the plant is indiscriminately harvested from its very natural habitat. Therefore, in vitro biomass production of this plant can be a sustainable alternative for plumbagin production. In this present study, it has been found that, compared to other cytokinins, biomass production was enhanced by using aromatic cytokinin meta-topolin (mT). The highest shoot buds produced by mT (1 mg/l) was 13.60 ± 1.14 after 14 d of culture establishment. After 84 d in the same medium, 129.8 ± 2.71 shoots were produced, and the fresh weight of the total biomass was 19.72 ± 0.65 g. The highest number of roots was induced (37.80 ± 0.84) with 1.0 mg/l Indole-3-butyric acid (IBA). The well rooted plantlets were acclimatized in field condition with 87%survival. The regenerated plants' genetic fidelity was accessed through molecular markers i.e. Inter simple sequence repeat (ISSR), Start codon targeted (SCoT) and cytology studies. The monomorphic bands amplified by the primers across in vivo and in vitro plants confer the genetic homogeneity of the regenerants. The plumbagin content from different parts of the in vitro grown plants in vivo mother plant was quantified through High-Performance Liquid Chromatography (HPLC), and found that they do not differ significantly. Even all parts of the in vitro plants produce plumbagin, roots contain the maximum amount (14.67 ± 0.24 mg/g dry weight basis). [ABSTRACT FROM AUTHOR]

This study aimed at investigating the chemical composition and the hepatoprotective activities of Plumbago indica L. and P. auriculata Lam. LC–MS/MS analyses for the hydroalcoholic extracts of the aerial parts of the two Plumbago species allowed the tentative identification of thirty and twenty-five compounds from P. indica and P. auriculata, respectively. The biochemical and histopathological alterations associated with thioacetamide (TAA)-induced liver fibrosis in rats were evaluated in vivo where rats received the two extracts at three different dose levels (100, 200 and 400 mg/kg p.o, daily) for 15 consecutive days with induction of hepatotoxicity by TAA (200 mg/kg/day, i.p.) at 14th and 15th days. Results of the present study showed a significant restoration in liver function biomarkers viz. alanine transaminase (ALT), aspartate transaminase (AST), gamma glutamyl transferase and total bilirubin. The liver homogenates exhibited increased levels of antioxidant biomarkers: reduced glutathione (GSH) and catalase (CAT), accompanied with decline in malondialdehyde (MDA). Furthermore, treated groups exhibited a significant suppression in liver inflammatory cytokines: tumor necrosis factor-α (TNF-α) and interlukin-6 (IL-6), and fibrotic biomarker: alpha smooth muscle relaxant. Histopathological examination of the liver showed normality of hepatocytes. Noteworthy, P. indica extract showed better hepatoprotective activity than P. auriculata, particularly at 200 mg/kg. To sum up, all these results indicated the hepatoprotective properties of both extracts, as well as their antifibrotic effect was evidenced by reduction in hepatic collagen deposition. However, additional experiments are required to isolate their individual secondary metabolites, assess the toxicity of the extracts and explore the involved mechanism of action. [ABSTRACT FROM AUTHOR]

The global potential of therapeutic plants in treating microbial illnesses is evident. This study focuses on the Plumbago zeylanica (P.zeylanica)plant and aims to isolate and investigate a bioactive compound with antifungal, antioxidant, and cancer-fighting properties. The compound identified as 2,4-Ditert butyl phenol (2,4-DTBP) was successfully extracted from P. zeylanica using Ethyl acetate and confirmed through GC–MS analysis. The antioxidant effects of 2,4-DTBP are well-known as it effectively suppresses oxidation, preventing material degradation and disintegration. Its ability to neutralize free radicals and reduce reactive oxygen species production makes it valuable in stabilizing various compounds. Notably, it enhances the durability and endurance of plastics, rubber, and polymers. The isolation and purification of 2,4-DTBP were accomplished using HPLC, and its structure was characterized as C14H22O through 1H NMR analysis. The fungicidal activity of 2,4-DTBP against Botrytis cinerea was proven through agar plate assay, and its cytotoxic activity was evaluated using MCF-7 cells (a breast carcinoma cell line) with an identified IC50 value of 5 μg/ml. This study provides insight into the medicinal properties of 2,4-DTPB and its effectiveness against cancer cells. Overall, further investigation and exploration of 2,4-DTBP's potential in cancer research would contribute to its potential application as a novel therapeutic agent in the future. [ABSTRACT FROM AUTHOR]

In this study, an efficient method for in vitro regeneration of Plumbago europaea was developed using direct and indirect organogenesis. Accordingly, micropropagation and regeneration were obtained on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of plant growth regulators. The effects of explant type and plant growth regulators on shoot organogenesis of P. europaea were evaluated. For the nodal explants, MS medium containing 0.5 mg/l TDZ (11.62 shoots per node) was the best medium for high frequency of micropropagation. In comparison, the highest percentage of direct organogenesis (70%) and number of shoots per explants (14.6) were acquired for the internode explants using 0.5 mg/l TDZ and 0.1 mg/l IAA. The obtained data revealed that TDZ is the most effective cytokinin for the direct shoot organogenesis. The highest indirect organogenesis rate was observed using 2 mg/l BA and 0.1 mg/l NAA for the internode explant. The maximum number of roots was distinguished on ½ MS medium containing 0.5 mg/l IBA (6.42). The rooted plantlets were gradually hardened and acclimatized under ex vitro conditions. As an important outcome, the active compound plumbagin was found mainly in the root tissues of the micro-propagated and regenerated plantlets. Taken all together, this study achieved a successful protocol for in vitro regeneration of P. europrea and could be considered for large-scale multiplication of this important medicinal plant. [ABSTRACT FROM AUTHOR]

Plumbago zeylanica L. (Plumbaginaceae) commonly known, as chitrak is pharmacologically important plant. Various studies have been undertaken to assess the pharmacological potential of different parts of the plant namely like roots, stem, flower, and leaves as antimicrobial, hepatoprotective, anticancer, antifertility, antiulcer, antifungal and wound healing. The intention of the present review is to deliver a concise account on its ethnobotanical uses, phytochemistry with an in-depth study of its phytoconstituents, facts and prospects of its potential pharmacological activities of this golden plant. An extensive literature survey was undertaken through different online platforms viz. Google Scholar and online databases namely PubMed, Science Direct and Springer. All papers based on traditional medicinal uses and pharmacological properties were included. Sixty three research articles and review articles were found to be apt for inclusion into the review. About 150 articles were retrieved for the purpose. The elaborative results vindicated that Plumbago zeylanica L. holds significant prospects in major health conditions such as diabetes, cardiovascular disorders, ulcer, liver problems, obesity, wound healing, cancer etc. [ABSTRACT FROM AUTHOR]

Key message: The present study provides comparative transcriptome analysis, besides identifying functional secondary metabolite genes of Plumbago zeylanica with pharmacological potential for future functional genomics, and metabolomic engineering of secondary metabolites from this plant towards diversified biomedical applications. Plumbago zeylanica is a widely used medicinal plant of the traditional Indian system of medicine with wide pharmacological potential to treat several disorders. The present study aimed to carry out comparative transcriptome analysis in leaf and root tissue of P. zeylanica using Illumina paired end sequencing to identify tissue-specific functional genes involved in the biosynthesis of secondary metabolites, contributing to its therapeutic efficacy. De novo sequencing assembly resulted in the identification of 62,321 "Unigenes" transcripts with an average size of 1325 bp. Functional annotation using BLAST2GO resulted in the identification of 50,301 annotated transcripts (80.71%) and GO assigned to 18,814 transcripts. KEGG pathway annotation of the "Unigenes" revealed that 2465 transcripts could be assigned to 242 KEGG pathway maps wherein the number of transcripts involved in secondary metabolism was distinct in root and leaf transcriptome. Among the secondary metabolite biosynthesis pathways, the cluster of "Unigenes" encoding enzymes of 'Phenylpropanoid biosynthesis pathway' represents the largest group (84 transcripts) followed by 'Terpenoid Backbone biosynthesis' (48 transcripts). The transcript levels of the candidate unigenes encoding key enzymes of phenylpropanoid (PAL, TAL) and flavanoid biosynthesis (CHS, ANS, FLS) pathways were up-regulated in root, while the expression levels of candidate "Unigenes" transcript for monoterpenoid (DXS, ISPF), diterpenoid biosynthesis (SPS, SDS) and indole alkaloid pathways (STR) were significantly higher in leaf of P. zeylanica. Interestingly, validation of differential gene expression profile by qRT-PCR also confirmed that candidate "Unigenes" enzymes of phenylpropanoid and flavonoid biosynthesis were highly expressed in the root, while the key regulatory enzymes of terpenoid and indole alkaloid compounds were up-regulated in the leaf, suggesting that (differences in) the levels of these functional genes could be attributed to the (differential) pharmacological activity (between root and leaf) in tissues of P. zeylanica. [ABSTRACT FROM AUTHOR]

A new spodumene-rich pegmatite was recently discovered on the north side of Plumbago Mountain, Oxford County, Western Maine. The site is about 1.5 km northwest of the famous Dunton gem tourmaline pegmatite. It is an albite-quartz-spodumene pegmatite containing gigantic crystals of spodumene and montebrasite. Some spodumene crystals are more than 11 m in length. The upper portions of the pegmatite contain up to 50 wt% spodumene, which makes it a potentially significant new lithium resource. Preliminary results indicate that Plumbago North Pegmatite contains about 10 Mt of ore with an average Li2O content of 4.68 wt% which is a higher average lithium content than any of the ten top spodumene-producing deposits in the world. [ABSTRACT FROM AUTHOR]

Plumbago zeylanica L., a wild shrub, is a vital natural source of plumbagin, a potent 1,4-naphthoquinone renowned for its anti-cancer properties, notably effective against breast, prostate, and ovarian cancers. Traditional plumbagin extraction, involving root uprooting and plant destruction, raises ecological concerns. The primary objective of this study is to enhance plumbagin production by incorporating the elicitation process into in vitro cultivation with regenerated plants that retain all of their intact organs. Seven different elicitors categorized into three distinct groups were employed to stimulate plumbagin content. Among the various elicitors used, this study marks the first application of biogenic silver nanoparticles (AgNPs) from Curcuma amada in stimulating plumbagin production in this plant. The maximum plumbagin content, recorded at 8.98 ± 0.24 mg/g dry weight basis, was found in the roots when elicited with AgNPs at a concentration of 15 mg/l. In addition to that, biotic elicitors (yeast extract, chitosan and casein hydrolysate) and heavy metals (lead, cobalt and nickel) also successfully elicit plumbagin in the root and aerial parts of the plants, quantified through High Performance Liquid Chromatography (HPLC). In our study, we found that certain elicitors induced root browning and tissue necrosis, as confirmed by propidium iodide (PI) staining. The most significant browning effects were observed with chitosan from biotic sources and lead from heavy metals, while no such effects were associated with AgNPs at any concentration. Utilizing intact, entire plants as the subjects for elicitation in our study is a valuable aspect. This approach closely replicates the natural process occurring in intact plants, enhancing the relevance of our findings to practical situations.Key message: Utilizing silver nanoparticles alongside diverse biotic and heavy metal elicitors applied to entire plants in liquid cultures facilitates the sustainable production of plumbagin from various plant organs. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. (Plumbaginaceae) is a medicinal flowering shrub which produces plumbagin that shows diverse pharmacological attributes. P auriculata accumulates a very important napthaquinone, plumbagin which exhibits a wide range of medicinal properties. The present study is aimed at in vitro propagation of P auriculata and a comparative quantification of plumbagin in in vitro and in vivo grown plants. Direct shoot regeneration was induced from the nodal explants of P auriculata. Murashige and Skoog medium supplemented with different combination of 6-Benzylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA). Best response was obtained with BAP 1.5 mg/L and NAA 2.0 mg/L after 15 days in in vitro culture. Maximum number of roots were induced on ½ strength MS medium supplemented with 2% sucrose (w/v) and 0.7 mg/L Indole-3-acetic acid. Plumbagin was extracted by microwave-assisted extraction method and content was estimated from stem, leaf and root of both propagated plants by HPTLC. It was found that the roots of both in vivo (0.01% w/w) and in vitro (0.066% w/w) grown plants contain the highest amount of plumbagin. In vitro grown roots produced five-fold more plumbagin as compared to in vivo regenerated roots. Maximum increase of plumbagin production was observed in the in vitro grown stem i.e., seven-fold as compared to in vivo induced stem. In vitro propagation of plant provides a rapid and continuous supply of plumbagin while preserving the natural resource. [ABSTRACT FROM AUTHOR]

Cultivation of hairy roots is an effective method to get high in plumbagin secondary metabolites. With different genotypes, setting up a stable genetic transformation system is peculiar and difficult. The plumbagin is found in the roots of Plumbago auriculata L., a secondary metabolite with significant medicinal value. Still, the natural root grows slowly, and their accumulation period is lengthy (2–6 years). In this paper, we first explored the most effective Agrobacterium rhizogene-mediated (A4, ATCC 15834, and LBA 9402) genetic transformation to induce hairy root of P. auriculata. We compared the difference of the plumbagin concentration in the root between tissue culture and seedling. The results showed that the leaves were soaked with bacterial solution for 25–30 min and then transferred to 1/2 MS + acetosyringone 100 µM agar solidified medium for 2-5d. After co-culture, we transferred the leaves to 1/2 MS + Cefotaxime sodium of different concentrations sterilized for 7d. Under this scheme, three strains can induce hairy roots, with ATCC 15834 having the highest hairy root transformation efficiency (86.78 ± 0.74%) and the earliest root emergence time (8.33 ± 0.58 d). 1-month-grown hairy root showed an increase in plumbagin compared with the untransformed roots of 1-year-old live seedlings, with ATCC 15834 induced roots having the highest content of 38.95 mg·g−1 DW, which was 72.13 times higher than the untransformed roots and 3.95 times higher than that of 1-year-old live seedlings. This is an important experimental basis for biosynthesis mechanism of plumbagin and the feasibility of subsequent commercial production. Key message: A genetic transformation system was established for hairy root of P. auriculata by A. rhizogene. A reliable and rapid method was developed to obtain the plumbagin with high medicinal value. [ABSTRACT FROM AUTHOR]

Plumbagin is the major secondary metabolite found in Plumbago species, it exhibit a wide variety of pharmaceutical activities. The initial focus of this study was to establish a suitable protocol for direct shoot regeneration from nodal explants on Murashige and Skoog (MS) medium fortified with 6-benzylaminopurine (BAP) and α-naphthalene-acetic acid (NAA). Single shoot regenerated from the nodal explants when cultured on BAP alone, whereas multiple shoots regenerated with BAP and NAA. The maximum number of shoots were obtained on medium fortified with 5.5 µM BAP and 3.0 µM NAA. Furthermore, the shoot cultures were treated with biotic elicitors (lysates of Agrobacterium rhizogenes and Trichoderma viride and yeast extract). The application of elicitors was optimized by the Response Surface Methodology coupled with Box-Behnken design (RSM-BBD). The experimental and predicted values were analyzed and the elicitors were found to be stastically significant. Plumbagin was quantified by liquid chromatography/electrospray ionization tandem. The highest plumbagin yield was found to be 18-fold higher as compared to the control when treated with 1.5% A. rhizogenes lysate, 2.25% T. viride lysate and 2% yeast extract. The best model for optimum production of plumbagin was experimentally verified and the correlation between the predicted (1.751%) and actual values (1.732%) was found to be 98.7% for plumbagin production. The present study suggest that the elicitors used enhance the production of plumbagin considerably. It is the first ever study to report the successful utilization of lysates enhancing plumbagin production in the shoot cultures. Key message: In vitro production of plumbagin from Plumbago zeylenica. Analysis of plumbagin by LC-MS. Application of RSM to optimize the enhanced plumbagin yield by using eliciters. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this is the first study to analyze the essential oil of I P. zeylanica i and to evaluate its antibacterial and cytotoxic activities. The essential oil of I P. zeylanica i was characterized by the presence of oxygenated monoterpenes (5.5%), sesquiterpenes (26.2%), and oxygenated sesquiterpenes (53.4%). The EO exhibited a significant antibacterial activity against I Escherichia coli i (MIC 20 g/mL) and moderate antibacterial activities against I Staphylococcus aureus i , I Bacillus subtilis i , and I Pseudomonas aeruginosa i (MICs 80-320 g/mL). [Extracted from the article]

A high-performance thin-layer chromatography (HPTLC) method has been developed for the quantitative determination and validation of plumbagin in the methanolic fraction of Plumbago zeylanica. For achieving good separation, the mobile phase of toluene‒ethyl acetate (9:2, V/V) for plumbagin was used. Densitometric determination of plumbagin was carried out at 270 nm in reflection/absorption mode; the calibration curves were linear in the range of 100‒600 ng/spot. During analysis, the methanolic fraction of P. zeylanica L. showed the presence of plumbagin. The method is specific, simple, precise, and accurate. The obtained data can be used for the routine analysis of the reported biomarkers in crude drugs and extracts. The quantification and the method validation of these biomarkers have not yet been reported in P. zeylanica which can be utilized for the proper standardization of the plant. [ABSTRACT FROM AUTHOR]

Main Conclusion: Novel cytochrome P450s, CYP81B140 and CYP81B141 from Plumbago zeylanica were functionally characterized to understand their involvement in polyketide plumbagin biosynthesis. Further, we propose 3-methyl-1-8-naphthalenediol and isoshinanolone as intermediates for plumbagin biosynthesis. Plumbago zeylanica L. (P. zeylanica) is a medicinally important plant belonging to the family Plumbaginaceae. It comprises the most abundant naphthoquinone plumbagin having anti-cancer activity. Only the polyketide synthase (PKS) enzyme has been identified from the biosynthetic pathway which catalyzes iterative condensation of acetyl-CoA and malonyl-CoA molecules. The plumbagin biosynthesis involves hydroxylation, oxidation, hydration and dehydration of intermediate compounds which are expected to be catalyzed by cytochrome P450s (CYPs). To identify the CYPs, co-expression analysis was carried out using PKS as a candidate gene. Out of the eight identified CYPs, CYP81B140 and CYP81B141 have similar expression with PKS and belong to the CYP81 family. Phylogenetic analysis suggested that CYP81B140 and CYP81B141 cluster with CYPs from CYP81B, CYP81D, CYP81E and CYP81AA subfamilies which are known to be involved in the hydroxylation and oxidation reactions. Moreover, artificial microRNA-mediated transient individual silencing and co-silencing of CYP81B140 and CYP81B141 significantly reduced plumbagin and increased the 3-methyl-1-8-naphthalenediol and isoshinanolone content. Based on metabolite analysis, we proposed that 3-methyl-1-8-naphthalenediol and isoshinanolone function as intermediates for plumbagin biosynthesis. Transient silencing, over-expression and docking analysis revealed that CYP81B140 is involved in C-1 oxidation, C-4 hydroxylation and [C2–C3] hydration of 3-methyl-1-8-naphthalenediol to form isoshinanolone, whereas CYP81B141 is catalyzing [C2–C3] dehydration and C-4 oxidation of isoshinanolone to form plumbagin. Our results indicated that both CYP81B140 and CYP81B141 are promiscuous and necessary for plumbagin biosynthesis. This is the first report of identification and functional characterization of P. zeylanica-specific CYPs involved in plumbagin biosynthetic pathway and in general hexaketide synthesis in plants. [ABSTRACT FROM AUTHOR]

Main conclusion: Enhanced secretion of Na+ and Cl− in leaf glands and leaf vacuolar sequestration of Na+ or root retention of Cl−, combined with K+ retention, contribute to the improved salt tolerance of tetraploid recretohalophyte P. auriculata. Salt stress is one of the major abiotic factors threatening plant growth and development, and polyploids generally exhibit higher salt stress resistance than diploids. In recretohalophytes, which secrete ions from the salt gland in leaf epidermal cells, the effects of polyploidization on ion homeostasis and secretion remain unknown. In this study, we compared the morphology, physiology, and ion homeostasis regulation of diploid and autotetraploid accessions of the recretohalophyte Plumbago auriculata Lam. after treatment with 300 mM NaCl for 0, 2, 4, 6, and 8 days. The results showed that salt stress altered the morphology, photosynthetic efficiency, and chloroplast structure of diploid P. auriculata to a greater extent than those of its tetraploid counterpart. Moreover, the contents of organic osmoregulatory substances (proline and soluble sugars) were significantly higher in the tetraploid than in the diploid, while those of H2O2 and malondialdehyde (MDA) were significantly lower. Analysis of ion homeostasis revealed that the tetraploid cytotype accumulated more Na+ in stems and leaves and more Cl− in roots but less K+ loss in roots compared with diploid P. auriculata. Additionally, the rate of Na+ and Cl− secretion from the leaf surface was higher, while that of K+, Mg2+, and Ca2+ secretion was lower in tetraploid plants. X-ray microanalysis of mesophyll cells revealed that Na+ mainly accumulated in different cellular compartments in the tetraploid (vacuole) and diploid (cytoplasm) plants. Our results suggest that polyploid recretohalophytes require the ability to sequester Na+ and Cl−(via accumulation in leaf cell vacuoles or unloading by roots) and selectively secrete these ions (through salt glands) together with the ability to prevent K+ loss (by roots). This mechanism required to maintain K+/Na+ homeostasis in polyploid recretohalophytes under high salinity provides new insights in the improved maintenance of ion homeostasis in polyploids under salt stress. [ABSTRACT FROM AUTHOR]

Selection of elite accessions is important to get the maximum quantity of bioactive compounds in medicinal plants. In this study, thirteen accessions of Plumbago zeylanica L., a medicinal herb, was studied for phytochemical and genetic diversity analysis. Phytochemical analysis showed that accession number IC-524441 contains the highest amount of flavonoids, phenolic, tannin and plumbagin content, it also possesses maximum antioxidant activity. Genetic diversity analysis showed that 15 SCoT (Start codon targeted) and 20 CBDP (CAAT Box Derived Polymorphism) primers produced 86 and 110 amplicons in total and average were 5.73 and 5.5 amplicons/primer respectively. PIC values ranged from 0.12 to 0.37 and average is 0.25/primer in the case of SCoT marker whereas, in the case of CBDP marker it was 0.15 to 0.59 with average of 0.26/primer. Cluster analysis showed that SCoT marker provides three clusters where cluster 1 and cluster 2 have only 2 accessions while cluster 3 contains nine accessions. Similarly, CBDP marker provides three clusters where cluster 1 contains only 1 accession and cluster 2 and cluster 3 contains six accessions in each. Further AMOVA analysis of SCoT marker possesses maximum variation of 8% among agro-ecological regions whereas in case of CBDP marker its 5%. From the present investigation, it was found that IC-524441 is an elite accession and contains highest amount of bioactive compound. Our results also demonstrate that both SCoT and CBDP markers are informative and can be utilized for evaluation of genetic relationships among Plumbago zeylanica L. accessions. [ABSTRACT FROM AUTHOR]

The metabolite contents of the plants may vary with season and geographic variations, and this induces the biological potential of the plant species. The present study aimed to identify the elite chemotype(s) of Plumbago zeylanica, collected from the natural habitat of Gangetic plains on the basis of plumbagin content. The effect of intra-specific variability in the plumbagin content among the population was estimated by using high-performance thin-layer chromatography (HPTLC) densitometric method. Roots of thirteen naturally occurring populations of P. zeylanica from the entire range were collected, covering the wide topography from foothills up to the highest peak. The method developed for quantification of plumbagin was validated and found to be linear, specific and accurate with precision and accuracy. LOD and LOQ were 1.04 and 3.16 ng/spot. Precision studies (both inter-day and intra-day) were within the standard limit of API, with RSD (%) less than 3%. Quantification of plumbagin within population reveals that it varies from 0.0048 ± 0.0005 μg (NBP-22) to 0.1696 ± 0.003 μg (NBC-25) percent on per dry weight basis. Analysis of variance (ANOVA) suggests that there is a significant difference in plumbagin content among the population. UPGMA cluster analyses based on plumbagin content bifurcate the populations into two major clusters, representing the variation in metabolite content. The first major cluster having NBP-25 and NBP-18 accessions, NBP-25 having maximum plumbagin content was collected from Bankura, West Bengal. The study suggests the presence of chemotaxonomic variation among the population which may be due to the change in environmental/phytogeographical factors. [ABSTRACT FROM AUTHOR]

In the present work, a simple, rapid, reliable and accessible high-performance thin-layer chromatography (HPTLC) technique has been established for the concurrent quantification of plumbagin. The well-known medicinal plant, Plumbago zeylanica L., has been traditionally used to treat a variety of ailments in India and other countries. Chromatographic separation was conceded on pre-coated silica gel plates F254. The apposite mobile phase toluene‒acetic acid (9.0:0.5, V/V) was developed to expand the plates which separated components according to the marker compounds. Densitometric scanning was performed by CAMAG Scanner V and measured at wavelength 272 nm. The marker compounds were practically resolved with RF 0.44 ± 0.02 for plumbagin. Further, the antioxidant potential of the methanolic extract of P. zeylanica was also assessed with 1,1-diphenyl-2-picrylhydrazyl (DPPH) by using an ultraviolet (UV) spectrophotometer. The percentage inhibition of free radical was found to be 76.5%. The developed HPTLC method was validated for accuracy, linearity, precision and specificity. The extract has revealed considerable antioxidant activity. The reported existing phenolic and flavonoids compounds are responsible for the antioxidant activity of the plant extract as reported in the literature. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. is an ornamental plant native to South Africa and widely cultivated in China, but the cultivated plants are dominated by a single variety. The development of new varieties is of great commercial interest, and genetic diversity is the foundation of breeding programs. In this study, 85 progenies were obtained by crosses between Plumbago auriculata and Plumbago auriculata f. alba. The genetic diversity of these hybrids was evaluated using horticultural traits and ISSR and SRAP markers. Of the 25 horticultural traits evaluated, the largest variation was found in the beginning of the blooming period, and sepal length was the least variable trait. Correlation analysis showed that the wider the plant, the greater the number of inflorescences and the earlier the flowering. Seven factors explained 65.171% of the total variance; the first factor was leaf morphology, and the second factor was flower morphology. The genetic diversity of the 85 progenies was analyzed using seven pairs of SRAP primers and eight ISSR primers. The average number of effective alleles for 85 hybrids was 1.638, and the average Shannon index value was 0.507. The Nei genetic similarity coefficient indicated that the similarity between WLBS and WSBL was the highest, while that between BLWS and BSWL was the lowest. Analysis of molecular variance (AMOVA) indicated that the main variation was within populations. Cluster analysis based on horticultural traits and molecular markers divided all progenies into seven and five groups, respectively, and there were obvious differences between the two clusters. In this study, we created intermediate materials for future breeding, taking the first step in the cross-breeding of P. auriculata. [ABSTRACT FROM AUTHOR]

Utilization of bioresources for the synthesis of metal nanoparticles is the latest field in green chemistry. The present work reports the utilization of the aqueous bark extract of Plumbago zeylanica for the biosynthesis of Ag and Au NPs. The Ag and Au NPs thus obtained were characterized by UV-Vis, FT-IR, TEM, XRD, and EDAX analysis. The water-soluble components of the extract were responsible for the reduction of Ag and Au ions. FT-IR spectra revealed that the -OH and >C=O groups present in the biomolecules were responsible for reduction and stabilization of nanoparticles. TEM images showed the existence of spherical Ag and Au NPs with average size of 28.47 and 16.89 nm, respectively, which was further substantiated by XRD analysis. The presence of elemental Ag and Au along with C and O from the attached biomolecules was proved by EDAX analysis. The antimicrobial, antioxidant, and in vitro cytotoxic activities of the synthesized nanoparticles were studied by disc diffusion, DPPH, and MTT assay methods, respectively. The free radical inhibition was found to be 78.17 and 87.34 % for Ag and Au nanoparticles, respectively. The Ag and Au NPs showed 61.56 and 65.61 % toxicity against DLA cell line, respectively. The DNA binding ability of Ag and Au NPs were investigated using CT-DNA. The hyperchromism shift inferred the groove binding of nanoparticles with CT-DNA. [ABSTRACT FROM AUTHOR]

Blue flowers, which are rare, have long been a focus for researchers engaged in colored flower breeding. In this study, Plumbago auriculata, a plant with blue flowers, and its white flower forma Plumbago auriculata f. alba were used as research materials. Flower color quantification, environmental scanning electron microscopy (ESEM) observation of petal epidermal cells, and determination of the cell sap pH were carried out; moreover, metabolomic analysis was used to analyze the flavonoid metabolites of both types of petals. The results showed that the flower color of P. auriculata was bluish violet, and there was no significant difference in the epidermal cell distribution of the white and blue petals. The key substance that determined the bluish violet flower color was cyanidin-3-O-(6″-p-coumaroylglucoside) (Cy3-pC·G). Compared to the white petal cells, the blue petal cells exhibited up to 40 upregulated flavonoid compounds that were copigments. Together with the significantly increased pH (5.92 ± 0.12) of the petal cell sap, these copigments affected the color presentation of Cy3-pC·G, causing the final petal color of P. auriculata to be bluish violet. The results of this study indicate that cyanidin is an important anthocyanidin in blue flowers, which provides new insights into the breeding of blue flowers. [ABSTRACT FROM AUTHOR]

The present study describes a simple, reproducible, and cost-effective regeneration system using seaweed liquid extract (SLE) of Sargassum ilicifolium supplemented in Murashige and Skoog (MS) medium for in vitro seed germination, multiple shoot and root induction, and plumbagin accumulation in P. zeylanica. High rate of seed germination and seedling length was recorded on ½ − MS + SLE (2%) which was 1.11- and 1.28-fold higher as compared to GA3 (2.89 µM). The best response in terms of explants producing maximum number of shoots was recorded on MS medium supplemented with 4% SLE that was 2.26- and 1.37-fold higher than BAP (3.33 µM) alone and in combination with IAA (4.28 µM), respectively. High frequency root induction and plumbagin accumulation was recorded on ½ − MS + 2.5% SLE which showed 1.34-, 1.49-, and 1.44-fold increase for the roots per shoots, average root length, and plumbagin, respectively when compared with IBA (6.15 µM). Besides being an alternative to commercially available PGRs, this is the first report demonstrating the potential of SLE for enhanced growth and plumbagin accumulation in P. zeylanica. Key message: Efficient in vitro mass propagation protocol of P. zeylanica is developed using S. ilicifolium SLEs. SLEs with MS media were a substitute to the commercially available PGRs for micro-propagation and plumbagin production. [ABSTRACT FROM AUTHOR]

In the present investigation, the effective root compound of plumbagin of Plumbago zeylanica (Plumbaginaceae) was evaluated for chemical constituent and antimalarial effect against the fourth instar larvae of Anopheles stephensi Liston (Diptera). In the chromatographic analyses of root compound with Rf value of 0.788 and NMR analyses also revealed that the effective compound contain naphthoquinone plumbagin were identified as the major chemical constituent. Larval mortality was observed after 3 h of exposure period. The plumbagin compound showed remarkable larvicidal activity against A. stephensi (LC 32.65 and LC72.27 ppm). Histopathological effects of compound was observed in the treated larvae. Based on the results, the plumbagin compound of P. zeylanica can be considered as a new source of natural larvicide for the control of malarial vector. [ABSTRACT FROM AUTHOR]

Heteromorphic self-incompatibility (HetSI) is a strategy used to prevent selfing while favouring outcrossing in angiosperm. Although the genome, proteome and metabolome of homomorphic self-incompatibility (HomSI) have been investigated, metabolome findings have shown that energy deficiency is one of the factors leading to HomSI. However, the mechanism of HetSI remains unclear. This study investigates the alterations of metabolite fluxes in HetSI. Here, metabolic changes present in dimorphic styles as well as between self-incompatibility (SI) and self-compatibility (SC) pollinations of Plumbago auriculata Lam were simultaneously determined by gas chromatography–mass spectrometry (GC–MS). Fifty-three metabolites, mainly including other organic acids, amino acids, carbohydrates/glycosides, fatty acids/lipids, amines, amides, flavonoids and alcohols, were detected. The overall results showed that carbohydrates, which may affect pollen germination and pollen tube growth rate on stigmas, were abundant in S (short styles without pollination). Moreover, energy deficiency may not be a reason for HetSI because we found inflated levels of metabolites in SI pollinations. This study provided detailed insight into metabolic changes in HetSI and evidence for further studies of HetSI. [ABSTRACT FROM AUTHOR]

A single-chain variable fragment antibody (scFv) against plumbagin (PL) accumulated the PL production in the hairy roots of Plumbago zeylanica. Recombinant Agrobacterium rhizogenes (ATCC 15834) containing an scFv gene against PL (PL-scFv) were obtained through triparental mating and transformed into P. zeylanica to induce PL-scFv protein in the hairy roots. Up to 40 μg recombinant PL-scFv were expressed per milligram of soluble protein in transgenic P. zeylanica hairy root cultures. The mean PL content obtained from transgenic hairy roots (12.24 μg/100 mg dry weight) exhibited 2.2 times higher than those obtained from wild-type (5.48 μg/100 mg dry weight). The high correlation between the PL-scFv expression level and PL content of the recombinant plants suggested that the PL biosynthesis pathway had been modulated by the expression of PL-scFv protein in the hairy roots of P. zeylanica. [ABSTRACT FROM AUTHOR]

Quantitative cell and organelle dynamics of the male gamete-producing lineage of Plumbago zeylanica were examined using serial transmission electron microscopic reconstruction at five stages of development from generative cell inception to sperm cell maturity. The founder population of generative cell organelles includes an average of 3.88 plastids, 54.9 mitochondria, and 3.7 vacuoles. During development the volume of the pollen grain increases from 6,200 μm3 in early microspores to 115,000 μm3 at anthesis, cell volume of the male germ lineage decreases more than 67% from 362.3 μm3 to 118.4 μm3. By the time the generative cell separates from the intine, plastid numbers increase by >600%, mitochondria by 250%, and vesicles by 43 times. A cellular projection elongates toward and establishes an association with the vegetative nucleus; this leading edge contains plastids and numerous mitochondria. When the generative cell completes its separation from the intine, organellar polarity is reversed and plastids migrate to the opposite pole of the cell. Cytoplasmic microtubules are common in association with cellular organelles. Plastids accumulate at the distal end of the cell as a linked mass, apparently adhered by lateral electron dense regions. Before division of the highly polarized generative cell, plastids decrease in number by 16%, whereas mitochondria increase by ∼90% and vacuoles increase by ∼140% from the prior stage. After mitosis, the resultant sperm cells differ in size and organelle content. The sperm cell associated with the vegetative nucleus (Svn) contains 62.7% of the cytoplasm volume, 87% of the mitochondria, 280.4 vesicles (79% of those in the generative cell), and 0.6% of the plastids. At maturity, the Svn mitochondria increase by 31% and the cell contains an average of 0.4 plastids, 158.9 vesicles, and 0.36 microbodies. The mature unassociated sperm (Sua) contains 39.8 mitochondria (up 3.3%), 24.3 plastids (down 31%), 91.1 vesicles (up 54.9%), and 3.18 microbodies. The small number of organelles initially in the generative cell, followed by their rapid multiplication in a shrinking cytoplasm suggests a highly competitive cytoplasmic environment that would tend to eliminate residual organellar heterogeneity. Cell and cytoplasmic volumes vary as a consequence of fluctuations in the number and size of large vesicles or vacuoles, as well as loss of cytoplasmic volume by (1) formation of “false cells” involving amitotic cytokinesis, (2) “pinching off” of cytoplasm, and (3) dehydration of pollen contents prior to anthesis. [ABSTRACT FROM AUTHOR]

The simultaneous and sequential dual elicitation effect on plumbagin production in Plumbago indica L. root cultures, revealed that combination of chitosan (150 mg L−1) with ʟ-alanine (5 mM) or methyl-β-cyclodextrin (MCD; 2 mM) significantly increased plumbagin production, but in the different treatment manners. The simultaneous treatment using chitosan + ʟ-alanine on a 14-day-old culture enhanced plumbagin production to 14.62 mg g−1 DW, while the sequential additions of MCD to a 12-day-old culture followed by chitosan after 48 h enhanced production of plumbagin to 14.33 mg g−1 DW. The plumbagin productivity from both treatments were up to 1.3- and 8-fold higher than the chitosan treated (10.93 mg g−1 DW) and untreated root cultures (1.76 mg g−1 DW). Moreover, the present studies provided new information on the effect of simultaneous and sequential elicitation on plumbagin-producing P. indica root cultures using chitosan in combinations with MCD or ʟ-alanine. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. (Plumbaginaceae) is an ornamental/medicinal flowering shrub. However, it could be stop growing under 5 °C resulting in its poor germplasm resources. Increasing the tolerance of polyploids to environmental stress will enrich its germplasm resources. In this study, we thus employed the stem segments and buds exposed to pendimethalin and trifluralin in vitro to conduct an effective polyploid protocol, in which buds were cultured for 7 days in MS medium with 800 μM. In this study, we have developed a novel polyploid identification method based on accuracy and efficiency. Early screening was performed based on the morphological characteristics of this plants, and then polyploidy was determined by flow cytometry. The number of chromosomes was determined by the chromosomal accounting. At the anatomical level, in comparison with diploids, the root parenchyma, stem collenchyma and tetraploid spongy tissues were thickened, the guard cell size and vascular bundles number were increased, and the stomata were widened; but the stomatal density was decreased. After 24 h of cold stress, the maximal quantum yield of photosystem II (Fv/Fm) and maximum primary yield of photochemistry of PSII (Fv/Fo) of diploids decreased significantly. Conversely, the minimal value of chlorophyll a fluorescence (Fo), relative electrical conductivity and malondialdehyde increased markedly. Accordingly, the cold tolerance of the tetraploids presented better than these of the diploids. Taken together, our study has first developed an effective protocol to obtain and identify the tetraploid of P. auriculate plants. Furthermore, it was proved that this polyploid has presented improving cold tolerance and enriching phenotypic properties. These findings could be useful for improving cold-tolerance breeding and enriching genetic diversity of P. auriculate plants. Key message: We used stem segments and buds exposed to pendimethalin and trifluralin in vitro to conduct polyploids of Plumbago auriculata and compared characterizations including cold tolerance between diploids and polyploids. [ABSTRACT FROM AUTHOR]

Background: Historically, plants have proven their value as a source of phytochemicals with therapeutic potentials and recently they play an important role in the discovery of novel drugs. Objectives: The current study aimed to investigate new antiobesity drugs from Plumbago europaea and Plumbago auriculata through the inhibition of the adsorption of dietary lipids. In vitro porcine pancreatic lipase inhibitory tests were conducted with weight reduction property as well as this study aimed to explore the antioxidant potential and to estimate total phenolic, flavonoid, and tannin contents in both of the studied species. Methods: Antioxidant capacity was evaluated using ferric reducing antioxidant power and DPPH assays, and porcine pancreatic lipase inhibitory tests were conducted using the UV spectrophotometric method, while total flavonoid, phenol, and tannin contents were estimated using standard phytochemical analytical methods. Results: Antioxidant potential and total flavonoid, phenol, and tannin contents of P. europaea were significantly higher than those of P. auriculata, and both of the studied species have potential antiobesity activity in comparison with orlistat. Conclusion: Results of the present study show that both of the studied Plumbago species consist of bioactive compounds that can act as lipase inhibitors and therefore can be useful for the development of functional foods against obesity. It can also be used as a source of lead compounds for designing new antiobesity drugs. Further isolation, identification, and characterization of phyto-active compounds responsible for antiobesity action are required to evaluate the full therapeutic potentials of these plants. [ABSTRACT FROM AUTHOR]

In a search for natural products that could be used to control the vectors of tropical diseases, extracts of medicinal plants Plumbago zeylanica and Cestrum nocturnum have been tested for larvicidal activity against second, third, and fourth instar larvae of Aedes aegypti. The LC values of all the extracts in different solvents of both the plants were less than 50 ppm (15.40-38.50 ppm) against all tested larval instars. Plant extracts also affected the life cycle of A. aegypti by inhibition of pupal development and adult emergence with increasing concentrations. The larvicidal stability of the extracts at five constant temperatures (19°C, 22°C, 25°C, 28°C, and 31°C) evaluated against fourth instar larvae revealed that toxicity of both plant extracts increases with increase in temperature. Toxicity studies carried out against fish species Poecilia reticulata, the most common nontarget organism in the habitats of A. aegypti, showed almost nil to meager toxicity at LC and LC doses of the plant extracts. The qualitative analysis of crude extracts of P. Zeylanica and C. nocturnum revealed the presence of bioactive phytochemicals with predominance of plumbagin in P. zeylanica and saponins in C. nocturnum. Partially purified plumbagin from P. zeylanica and saponins from C. nocturnum were obtained, and their presence was confirmed by thin-layer chromatography and biochemical tests. The bioassay experiment of partially purified secondary metabolites showed potent mosquito larvicidal activity against the fourth instar larval form. Therefore, this study explored the safer and effective potential of plant extracts against vector responsible for diseases of public health importance. [ABSTRACT FROM AUTHOR]

The solubility of 1,4-naphthoquinone, plumbagin, lawsone, and juglone in supercritical carbon dioxide was determined spectroscopically at 40°C, and in the pressure range 8–18 MPa. Their solubilities at 12 MPa were between 0.3 and 10 g L−1. Plumbagin from Plumbago scandens L. roots was extracted at 40°C and 20 MPa. The extracted plumbagin mass fraction was up to 0.2% in fresh roots but down to about 0.006% in aged roots. n-Hexane and chloroform extraction of such aged roots indicates that the older and dryer the roots are, the stronger they bind plumbagin. Reversed-phase HPLC indicated a relatively pure plumbagin extract with supercritical carbon dioxide. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

With its rare and naturally blue corolla, Plumbago auriculata Lam. has received attention and been introduced and planted worldwide. However, it is sensitive to low temperatures. Continuous low temperatures cause the stagnation of plant growth and the disappearance of ornamental traits. Currently, there is no report on the response of P. auriculata to low temperature. In this study, the chlorophyll fluorescence parameters of P. auriculata leaves were analysed after 10 days of low-temperature stress, and 943 differentially expressed genes were identified via high-throughput RNA sequencing. P. auriculata copes with low-temperature stress by changing the pathways of sugar metabolism, glutathione metabolism and lipid metabolism; however, the decrease in the assimilation level caused by damage to the photoreaction system is an important reason for plant growth stagnation. In addition, we identified 47 differentially expressed transcription factors, including the upregulated MYBS3 transcription factor, which is involved in the MYBS3-dependent pathway that is distinct from the DREB/CBF pathway. Our data reveal the cause of P. auriculata stagnation at low temperatures and provide valuable information for further studies on cold-response mechanisms and the genetic improvement of cold tolerance in P. auriculata. [ABSTRACT FROM AUTHOR]

Plumbago rosea L. (Plumbaginaceae), is a medicinal shrub commercially exploited for its naphthoquinone principle, plumbagin, extracted from the roots especially for treating skin disorders. As the plant is exploited from the wild without being replenished, conservation of the species becomes inevitable. Synthetic seeds would provide for effective conservation, germplasm exchange and distribution of this species. A reliable protocol for synthetic seed production in Plumbago rosea has been developed encapsulating the axillary buds. The axillary buds from P. rosea cultures established and multiplied using the nodal explants in Murashige and Skoog (MS) medium supplemented with Benzyl Adenine (BA) 1.5 mg/L and Indole 3-Acetic acid 1.0 mg/L, were used for synseed production. The plantlet conversion efficiency was the highest in synthetic seeds developed with sodium alginate 2.5% in modified MS with 0.4 M sucrose and CaCl2 100 mM. This combination gave the earliest bud initiation (9.19 ± 0.39 days) and maximum number of shoots per explant (2.31 ± 0.16 shoots). Microshoots from the culture, when inoculated on to MS medium supplemented with Naphthalene Acetic Acid 1.0 mg/L gave the best rooting response with 10.67 ± 0.94 roots per plant and 5.42 ± 0.29 cm root length. This is the first report of synthetic seed production in P. rosea using axillary buds as explant. [ABSTRACT FROM AUTHOR]

The article discusses a study on the bioactive compounds from Plumbago zeylanica, a semiclimbing medicinal plant, focusing on the isolation of dihydroflavonol, xanthine oxidase inhibition and antioxidant activity by P. zeylanica root extract. It sates that the isolated compounds from P. zeylanica root extract were 2-(3,4-dihydroxyphenyl)-3,5,6-trihydroxychromen-4-one and 3-(2,5-dimethylphenyl)-1-(2-hydroxyphenyl)-propenone. The results of the study are outlined.

Plumbagin is associated with potent antimicrobial and anticancer properties. However, due to poor supply of the natural product, efforts are being made to improve plumbagin biosynthesis and bioproduction. The aim of this work was to enhance production of plumbagin from root cultures of Plumbago indica L. through precursor feeding using l-alanine followed by in situ adsorption of plumbagin on the nonpolar copolymer adsorbent, styrene-divinylbenzene resin (Diaion HP-20). l-alanine fed at a concentration of 5 mM to 14 days old root culture followed by the sequential addition of Diaion HP-20 (10 g L) after 36 h of l-alanine-fed significantly increased plumbagin production to 22.4 mg g dry weight (DW). The level of productivity obtained was 14- and 1.6-fold higher than that achieved using untreated root cultures (1.6 mg g DW) or l-alanine feeding alone (14.4 mg g DW) within 16 days of the culture. The results of this work suggest the use of precursor feeding in combination with in situ adsorption as an easy and cost effective tool for the large-scale production of medicinally valued compounds like plumbagin. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study of anatomy of leaves, stems and roots of three species of Plumbago, namely P. auriculata Lam., P. indica L. and P. zeylanica L. by light microscopy. The paper also provides qualitative and quantitative analysis of the naphthoquinone, plumbagin-a major constituent present in these species-using UPLC-UV. Microscopic examinations revealed the presence of distinctive differences in the anatomical features of the leaf, stem and root of the three species, and these can thus be used for identification and authentication of these species. UPLC-UV analysis showed the highest concentration of plumbagin in the roots of P. zeylanica (1.62 % w/w) followed by the roots of P. indica (0.97 % w/w) and then P. auriculata (0.33-0.53 % w/w). In contrast, plumbagin was not detected in the stems and leaves of P. indica and in the leaves of P. auriculata, whereas very low concentrations (<0.02 % w/w) of plumbagin were detected in the stems and leaves of P. zeylanica and in the stems of P. auriculata. HPTLC fingerprints of the leaf and root of the three species exhibited distinguishable profiles, while those of the stems were undifferentiated. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effects of 12 biotic and abiotic elicitors for increasing the production of plumbagin in Plumbago indica root cultures. Results: Most elicitors showed minimal effects on the root dry weight, except for 250 mg chitosan l and 10 mM l-alanine that markedly decreased root biomass by about 40 % compared to the untreated root cultures (5 g l). Treatments with 100 µM AgNO significantly increased intracellular plumbagin production by up to 7.6 mg g DW that was 4-fold more than the untreated root cultures (1.9 mg g DW). In contrast, treatments with 150 mg chitosan l, 5 mM l-alanine, and 50 µM 1-naphthol significantly enhanced the extracellular secretion of plumbagin by up to 10.6, 6.9, and 5.7 mg g DW, respectively, and increased the overall production of plumbagin by up to 12.5, 12.5, and 9.4 mg g DW, respectively. Conclusions: Chitosan (150 mg l), l-alanine (5 mM), and 1-naphthol (50 µM) were the best elicitors to enhance plumbagin production in P. indica root cultures. [ABSTRACT FROM AUTHOR]

Abstract—Among the most hopeful biomaterials, metallic nanoparticles with antibacterial and anticancer properties are expected to open new avenues to fight and prevent various cancer and infectious diseases. The aim of the current study was the biosynthesis of plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone-AgNPs (P-AgNPs) using the endophytic fungus Fusarium solani isolated from an endangered medicinal plant Plumbago rosea. The fungus was identified according to its morphological characteristics and nuclear ribosomal DNA ITS sequence analysis. The synthesized P-AgNPs were initially noticed through visual color change from yellow to reddish brown and further confirmed by surface plasmonic resonance (SPR) band at 450 nm using UV-visible spectroscopy. Fourier transform infrared (FTIR) analysis showed amines and amides that are responsible for the stabilization of P-AgNPs. High-resolution scanning electron microscopy (HRSEM) showed that P-AgNPs were well dispersed, spherical, and well within the range of 23.2, 33.2 and 33.7 nm. X-ray diffraction (XRD) study revealed crystalline nature of P-AgNPs. These P-AgNPs displayed good antibacterial activity in dose dependant manner. The synthesized P-AgNPs exhibited dose-depended cytotoxicity against MCF-7 human breast cancer cells, the inhibitory IC50 were found to be 14.5 μg/mL. These nanoparticles were further studied for their anticancer activity and showed high selective toxicity against the MCF-7 breast cancer cell line. The anticancer activity also executed through inhibiting the cells at the phase DNA synthesis. [ABSTRACT FROM AUTHOR]

Plumbago zeylanica L. (PZ) is a significant medicinal plant in Ayurveda, so is used for the treatment of various disorders. The main active part of this plant is the root, and due to its inherent uses, it has been exploited hence becoming an endangered species. Dyerophytum indicum (Gibbs ex Wight) Kuntze (DI), mainly considered as a substitute of PZ, is also an important folklore medicine, used in many health problems. Both plants are much similar in their physical as well as chemical properties. However, an effective validation is required before declaration of substitution. In the present study, quantitative and qualitative estimations were performed on both plants with the help of modern analytical techniques. Simultaneous high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) and quantitative determinations ofβ-sitosterol have been performed for comparing both plants, i.e., PZ and DI. HPTLC fingerprinting analysis was also performed comparatively in different plant parts of PZ and DI. Successive extracts from different plant parts were evaluated for TLC separation profile of secondary metabolites. A comparative polyphenolic content- and antioxidant screening was evaluated to check the free radical scavenging effect of both plants (leaf, stem, and root) in comparison with the standards gallic and ascorbic acid. [ABSTRACT FROM AUTHOR]

novel naphthoquinone ( 1) was isolated from the methanol extract of P. zeylanica roots in addition to a known compound plumbagin ( 2). Their structures were determined by UV, IR, MS, H, and C NMR spectroscopic analysis, including 2D NMR. [ABSTRACT FROM AUTHOR]

Background: Plumbagin is one of the pharmaceutically important biomolecule with anticancer potential. Among the plants reported to produce plumbagin, P. zeylanica topped the list. The plumbagin production is very slow with low yield and maximum 0.5% (of dry weight) was reported in P. zeylanica. To meet the increasing demand of the plumbagin at global level, the P. zeylanica are exploited at commercial level, which may pose serious threat on the germplasm of the plant populations. So, it is needed to enhance the contents of plumbagin in P. zeylanica using biotechnological approaches. Among the various methods used to enhance the contents of plumbagin in P. zeylanica, utilization of fungal endophytes to enhance the plumbagin contents is a widely accepted approach. As fungal endophytes have the potential to synthesize various secondary metabolites and also reported to influence the synthesis of the secondary metabolites in plants. In the present study, an attempt was made to assess the effect of fungal endophytes of the Plumbago zeylanica L. on enhancement of plumbagin contents at in vivo level. Results: Total 3 fungal endophytes were recorded from the roots of P. zeylanica collected from Khadki, Pune. The fungal endophytes were identified at morphological and molecular level. After 1 year of the treatment with fungal endophytes, significant enhancement of plumbagin was recorded in the roots of the P. zeylanica. Plumbagin contents in each were quantified against the standard plumbagin by employing LCMS-MS technique. Among the three fungal endophytes, the maximum enhancement of plumbagin content (122.67%) was reported with the treatment of Alternaria sp. (Isolate-3) in the roots of the P. zeylanica compared to control. Conclusion: Among the three fungal endophytes, the maximum enhancement of plumbagin content (122.67%) was reported with Alternaria sp. (Isolate 3) in the roots of the pot-grown plants of P. zeylanica at in vivo level. [ABSTRACT FROM AUTHOR]