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Abstract Background DNA methylation is a crucial epigenetic mechanism that regulates gene expression during plant growth and development. However, the role of DNA methylation in regulating the organ-specific functions of the invasive weed Mikania micrantha remains unknown. Results Here, we generated DNA methylation profiles for M. micrantha and a local congeneric species, Mikania cordata, in three vegetative organs (root, stem, and leaf) using whole-genome bisulfite sequencing. The results showed both differences and conservation in methylation levels and patterns between the two species. Combined with transcriptome data, we found that DNA methylation generally inhibited gene expression, with varying effects depending on the genomic region and sequence context (CG, CHG, and CHH). Genes overlapping with differentially methylated regions (DMRs) were more likely to be differentially expressed between organs, and DMR-associated upregulated differentially expressed genes (DEGs) were enriched in organ-specific pathways. A comparison between photosynthetic (leaf) and non-photosynthetic (root) organs of M. micrantha further confirmed the regulatory role of DNA methylation in leaf-specific photosynthesis. Integrating small RNA-Seq data revealed that 24-nt small interfering RNAs (siRNAs) were associated with CHH methylation in gene-rich regions and regulated CHH methylation in the flanking regions of photosynthesis-related genes. Conclusion This study provides insights into the complex regulatory role of DNA methylation and siRNAs in organ-specific functions and offers valuable information for exploring the invasive characteristics of M. micrantha from an epigenetic perspective.

The synthesis of silver nanoparticles using plant extracts is a promising field of research due to the versatile biomedical application of metal nanoparticles. In the present study, silver nanoparticles (AgNPs) were synthesized using the aqueous extract of Mikania cordata leaves where extract act as both reducing and capping agents. Successful biosynthesis of AgNPs had been studied using UV Spectrophotometry that recorded the surface plasmonic resonance peak at around 451 nm. The structural properties and morphology of AgNPs were confirmed by scanning electron microscope with Energy dispersive X-ray (SEM/EDX), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) spectroscopic techniques. In antioxidant assays, AgNPs were found as strong free radical scavenger as ascorbic acid (standard) with the values of 10.06 (EC50, μg/mL) and 20.94 (EC50, μg/mL) for DPPH and ABTS radicals, respectively. In antimicrobial study, the effectiveness of synthesized AgNPs was observed as follows: Shigella boydii > Staphylococcus aureus > Shigella dysenteriae > Escherichia coli. Moreover, the results of cytotoxic assay indicated that AgNPs inhibited the growth of EAC cells in dose-dependent manner. Overall results of this study suggested that the synthesized AgNPs from Mikania cordata leaves have the merits to use in the field of nanomedicines.

Background: DNA methylation is a crucial epigenetic mechanism that regulates gene expression during plant growth and development. However, the role of DNA methylation in regulating the organ-specific functions of the invasive weed Mikania micrantha remains unknown. Results: Here, we generated DNA methylation profiles for M. micrantha and a local congeneric species, Mikania cordata, in three vegetative organs (root, stem, and leaf) using whole-genome bisulfite sequencing. The results showed both differences and conservation in methylation levels and patterns between the two species. Combined with transcriptome data, we found that DNA methylation generally inhibited gene expression, with varying effects depending on the genomic region and sequence context (CG, CHG, and CHH). Genes overlapping with differentially methylated regions (DMRs) were more likely to be differentially expressed between organs, and DMR-associated upregulated differentially expressed genes (DEGs) were enriched in organ-specific pathways. A comparison between photosynthetic (leaf) and non-photosynthetic (root) organs of M. micrantha further confirmed the regulatory role of DNA methylation in leaf-specific photosynthesis. Integrating small RNA-Seq data revealed that 24-nt small interfering RNAs (siRNAs) were associated with CHH methylation in gene-rich regions and regulated CHH methylation in the flanking regions of photosynthesis-related genes. Conclusion: This study provides insights into the complex regulatory role of DNA methylation and siRNAs in organ-specific functions and offers valuable information for exploring the invasive characteristics of M. micrantha from an epigenetic perspective. [ABSTRACT FROM AUTHOR]

Mikania micrantha and Mikania cordata are two distinct species in China. The former is notorious as one of the top 100 worst invasive species, whereas the latter is an indigenous species harmless to native plants or the environment. They form an ideal congener pair for comparative studies aimed at deeply understanding the invasion mechanisms of the exotic weed. In this study, we have assembled and annotated the mitogenomes of both species using Illumina and PacBio sequencing data and compared their characteristic differences. The complete mitogenome of M. micrantha is a double-stranded DNA with a length of 336,564 bp, while the mitogenome of M. cordata exhibits a branching structure, consisting of two small circular molecules and six linear molecules, with a combined length totaling 335,444 bp. Compared to M. cordata, M. micrantha has less SSRs, tandem repeats, dispersed repeats, mitochondrial protein coding genes (PCGs). The two plants show similar codon usage patterns. This comparative study has revealed the structure and function of the mitogenomes of the two species and laid a solid foundation for investigating the effects of gene loss and duplication on the development of invasive traits in M. micrantha., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The majority of the current anticoagulant drugs are chemically synthesised and to date, very limited sources are taken from natural-based agents. The objective of this study was to investigate the in vitro effect of the leaves extract of Mikania cordata (Selaput Tunggul) on basic coagulation activities and to identify its bioactive compounds. In this study, blood donors were divided into two groups where twenty-six blood samples were collected from healthy volunteers for prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT) tests, whilst for the evaluation of the effect of Mikania extracts on factor levels, another twenty-seven healthy donors were recruited. Five factor levels namely factor VII, IX, X, II and I were measured in citrated plasma treated with two different aqueous leaves concentration at 12.5 and 25.0 mg/mL. The control used was normal saline (untreated). Identification of bioactive compounds were analysed using gas chromatography mass spectrometry (GCMS) in aqueous solution. Significant prolongation of both APTT and TT in a concentration-dependent manner (p < 0.01) was observed. In PT assay, a significant reduction of clotting time (p < 0.01) at 3.13 mg/mL and a significant prolongation of clotting time (p < 0.01) at 12.5 and 25.0 mg/mL were recorded. Percentage of factors (VII, IX, X, II and I) in untreated and treated plasma with 12.5 and 25.0 mg/mL of M. cordata extracts were significantly reduced compared to control. The GCMS has identified 16 and 15 constituents in the ethanol and aqueous extract; subsequently and supports the finding of a strong anticoagulant effect of the extract. In conclusion, the results of this study show that the aqueous extract of Mikania cordata leaves has anticoagulant effects in a concentration-dependent manner. The GCMS results showed that the aqueous extract contains many bioactive constituents that contribute to its anticoagulant activities. Thus, Mikana cordata can be explored further to be used as an ingredient for anticoagulant drugs in the future. [ABSTRACT FROM AUTHOR]

Abstract The aerial parts of extensively used ethnomedicinal plant Mikania cordata (Burm. f.) Robinson growing wild in Bangladesh were investigated to isolate and characterize compounds responsible for the bioactivities of the plant. In the present study, a new derivatives of betulinic acid, 16-hydroxy betulinic acid [3β,16-dihydroxy-lup-20(29)-en-28-oic] was isolated and the structure of the compound was determined by NMR spectroscopic means and comparing with available literature data. The isolated compound was then investigated for different pharmacological activities including antibacterial, antifungal, analgesic, anti-inflammatory and antipyretic potential employing different methods. The compound showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0 to 17.5 mm and antifungal activity with mycelial growth inhibition ranging from 37.6 to 54.5%. The MIC values for antibacterial and antifungal activities ranged from 31.5–125 and 250–1000 μg/mL respectively. The compound (50 and 100 mg/kg body weight) showed potent peripheral and central analgesic activity with 55.19% and 41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%, 79.18% elongation of reaction time, respectively. In anti-inflammatory activity screening, the compound (100 mg/kg b.w.) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan. In antipyretic assay, 16-hydroxy betulinic acid displayed a strong antipyretic effect in yeast-induced rats. From the present study it is apparent that 16-hydroxy betulinic acid might play vital role to establish M. cordata as ethnomedicinal plant to treat wound, cuts and fever. [ABSTRACT FROM AUTHOR]

Mikania cordata, the only native congener of the invasive weed Mikania micrantha in China, is an ideal species for comparative study to reveal the invasion mechanism. However, its genome resources are lagging far behind its congener, which limits the comparative genomic analysis. Our goal is to characterize the genome of M. cordata by next-generation sequencing and propose a scheme for long-read genome sequencing. Previous studies have shown that the genomic resources of the host plant would be affected by the endophytic microbial DNA. An aseptic sample of M. cordata will ensure the proper genome in downstream analysis. Because endophytes are ubiquitous in the greenhouse-grown M. cordata, the in vitro culture with cefotaxime or timentin treatment was undertaken to obtain the aseptic plantlets. The in vivo mother plant and in vitro plantlets were used to survey the genome. The microbial contamination in M. cordata was recognized by blast search and eliminated from the raw reads. The decontaminated sequencing reads were used to predict the genome size, heterozygosity, and repetitive rate. The in vivo plant was so contaminated that microbes occupied substantial sequencing resources and misled the scaffold assembly. Compared with cefotaxime, treatment with timentin performed better in cultivating robust in vitro plantlets. The survey result from the in vitro plantlets was more accurate due to low levels of contamination. The genome size was estimated to be 1.80 Gb with 0.50% heterozygosity and 78.35% repetitive rate. Additionally, 289,831 SSRs were identified in the genome. The genome is heavily contaminated and repetitive; therefore, the in vitro culture technique and long-read sequencing technology are recommended to generate a high-quality and highly contiguous genome.

Mikania micrantha and Mikania cordata are the only two species in genus Mikania (Asteraceae) in China. They share very similar morphological and life-history characteristics but occupy quite different habitats. Most importantly, they generate totally different ecological consequences. While M. micrantha has become an exotic invasive weed, M. cordata exists as an indigenous species with no harmful effects on native plants or habitats. As a continuous study of our previously reported M. micrantha chloroplast (cp) genome, in this study we have further sequenced the M. cordata cp genome to (1) conduct a comparative genome analysis to gain insights into the mechanism of invasiveness; (2) develop cp markers to examine the population genetic adaptation of M. micrantha ; and (3) screen variable genome regions of phylogenetic utility. The M. cordata chloroplast genome is 151,984 bp in length and displays a typical quadripartite structure. The number and distribution of protein coding genes, tRNA genes, and rRNA genes of M. cordata are identical to those of M. micrantha . The main difference lays in that the pseudogenization of ndhF and a 118-bp palindromic repeat only arises in M. cordata . Fourteen highly divergent regions, 235 base substitutions, and 58 indels were identified between the two cp genomes. Phylogenetic inferences revealed a sister relationship between M. micrantha and M. cordata whose divergence was estimated to occur around 1.78 million years ago (MYA). Twelve cpSSR loci were detected to be polymorphic and adopted to survey the genetic adaptation of M. micrantha populations. No cpSSR loci were found to undergo selection. Our results build a foundation to examine the invasive mechanism of Mikania weed. [ABSTRACT FROM AUTHOR]

Mikania cordata is widely used for the treatment of cuts, wounds, and dengue fever in Bangladesh. In the present study, essential oil (12.5, 25 and 50 mg/kg) and two extracts, viz ., chloroform and ethyl acetate extracts (200, 400, 800 mg/kg b.w.) were tested for peripheral and central anti-nociceptive activity by acetic acid-induced writhing and hot plate method, respectively. Carrageenan-induced rat paw edema assay and yeast-induced hyperthermia assay were also carried out to evaluate anti-inflammatory and antipyretic properties of oil and extracts, respectively at aforesaid doses. The essential oil (50 mg/kg), chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) showed potent peripheral anti-nociceptive activity having 47.33%, 29.33% and 16.65% of writhing inhibition, respectively, comparable with standard diclofenac (52.0%). Essential oil (50 mg/kg), chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) presented promising central anti-nociceptive activity as well having 95.86%, 79.18% and 42.37% elongation of reaction time, respectively, at 90 min after administration of essential oil, ethyl acetate extract and 60 min after administration of chloroform extract. In anti-inflammatory activity screening, the essential oil (50 mg/kg) produced the highest 72.80% edema inhibition at 4 h after administration of carrageenan which was comparable with that of standard phenylbutazoe (87.87%). On the other hand, chloroform extract (800 mg/kg) and ethyl acetate extract (800 mg/kg) showed up to 34.31% and 15.27% of edema inhibition, respectively, at 4 h after administration of carrageenan. In antipyretic assay, the essential oil and chloroform extract displayed a strong antipyretic effect in yeast-induced rats, whereas the ethyl acetate extract had no antipyretic activity. The present study revealed anti-nociceptive, anti-inflammatory and antipyretic potential of M. cordata which could be the therapeutic option against fever, inflammations as well as painful conditions and confirmed the traditional use of M. cordata . [ABSTRACT FROM AUTHOR]

Ｔｈｉｓ ｓｔｕｄｙ ａｉｍｅｄ ｔｏ ｃｏｎｆｉｒｍ ｔｈｅ ｃｈｒｏｍｏｓｏｍｅ ｎｕｍｂｅｒ ｏｆ Ｍｉｋａｎｉａ ｃｏｒｄａｔａ （Ａｓｔｅｒａｃｅａｅ）， ａ ｎａｔｉｖｅ ｐｌａｎｔ ｉｎ Ｃｈｉｎａ， ａｎｄ ｔｏ ｔｅｓｔ ｔｈｅ ｐｏｓｓｉｂｌｅ ｈｙｂｒｉｄｉｚａｔｉｏｎ ｓｃｅｎａｒｉｏ ｂｅｔｗｅｅｎ Ｍ． ｃｏｒｄａｔａ ａｎｄ ｉｔｓ ｉｎｖａｓｉｖｅ ｃｏｎｇｅｎｅｒ Ｍ． ｍｉｃｒａｎｔｈａ ｆｒｏｍ ａ ｃｙｔｏｌｏｇｉｃａｌ ｐｅｒｓｐｅｃｔｉｖｅ． Ｃｈｒｏｍｏｓｏｍｅ ｎｕｍｂｅｒ ａｎｄ ｃｈｒｏｍｏｓｏｍｅ ｍｏｒｐｈｏｌｏｇｙ ｏｆ ｆｏｕｒ ｐｏｐｕｌａｔｉｏｎｓ ｉｎ Ｍ． ｃｏｒｄａｔａ ｗｅｒｅ ｉｎｖｅｓｔｉｇａｔｅｄ． Ｔｈｅｓｅ ｉｎｃｌｕｄｅｄ Ｈｕａｌｉａｎ， Ｍｉａｏｌｉ， Ｙｉｌａｎ ａｎｄ Ｔａｉｐｅｉ ｐｏｐｕｌａｔｉｏｎｓ ｆｒｏｍ Ｔａｉｗａｎ， Ｃｈｉｎａ． Ｔｈｅ ｃｈｒｏｍｏｓｏｍｅ ｎｕｍｂｅｒ ２ｎ＝ ３６ ｗａｓ ｄｅｔｅｒｍｉｎｅｄ ｆｏｒ ａｌｌ ｆｏｕｒ ｐｏｐｕｌａｔｉｏｎｓ． Ｔｈｅｉｒ ｋａｒｙｏｔｙｐｅｓ， ａｌｌ ｆｏｒｍｕｌａｔｅｄ ａｓ ２ｎ＝１８ｍ＋１８ｓｍ， ｗｅｒｅ ｃｈａｒａｃｔｅｒｉｚｅｄ ｂｙ ｈａｖｉｎｇ ａ ｒｅｍａｒｋａｂｌｙ ｌａｒｇｅｒ， ｓｕｂｍｅｄｉａｎ ｃｅｎｔｒｏｍｅｒｉｃ ｃｈｒｏｍｏｓｏｍｅ ｐａｉｒ ｗｉｔｈ ａ ｓｅｃｏｎｄａｒｙ ｃｏｎｓｔｒｉｃｔｉｏｎ ｉｎ ｔｈｅ ｍｉｄｄｌｅ ｏｆ ｔｈｅ ｌｏｎｇ ａｒｍｓ． Ａｌｌ ｔｈｅ ｋａｒｙｏｔｙｐｅｓ ｗｅｒｅ Ｓｔｅｂｂｉｎｓ’ｓ ２Ｂ ｔｙｐｅ． Ｔｈｅ ｉｎｔｒａｃｈｒｏｍｏｓｏｍａｌ ａｓｙｍｍｅｔｒｙ ｉｎｄｅｘ （Ａ１） ｖａｒｉｅｄ ｆｒｏｍ ０．３８ ｔｏ ０．３９， ａｎｄ ｔｈｅ ｉｎｔｅｒｃｈｒｏｍｏｓｏｍａｌ ａｓｙｍｍｅｔｒｙ ｉｎｄｅｘ （Ａ２） ｖａｒｉｅｄ ｆｒｏｍ ０．３０ ｔｏ ０．３２． Ｔｈｉｓ ｉｓ ｔｈｅ ｏｎｌｙ ｒｅｐｏｒｔ ｏｆ ｔｈｅ ｃｈｒｏｍｏｓｏｍｅ ｎｕｍｂｅｒ ｆｏｒ Ｍ． ｃｏｒｄａｔａ ｆｒｏｍ Ｃｈｉｎａ， ａｎｄ ａｌｓｏ ｔｈｅ ｆｉｒｓｔ ｋａｒｙｏｔｙｐｅ ｒｅｐｏｒｔ ｆｏｒ ｔｈｉｓ ｓｐｅｃｉｅｓ． Ｏｕｒ ｒｅｓｕｌｔｓ， ｔｏｇｅｔｈｅｒ ｗｉｔｈ ｐｒｅｖｉｏｕｓ ｒｅｐｏｒｔｓ， ｉｎｄｉｃａｔｅ ｔｈａｔ ｔｈｅｒｅ ｉｓ ａｎｅｕｐｌｏｉｄ ｖａｒｉａｔｉｏｎ ｗｉｔｈｉｎ ｔｈｉｓ ｓｐｅｃｉｅｓ， ｂｕｔ ２ｎ＝３６ （ｄｉｐｌｏｉｄ ｂａｓｅｄ ｏｎ ｘ＝１８） ｉｓ ｔｈｅ ｏｎｌｙ ｎｕｍｂｅｒ ｃｕｒｒｅｎｔｌｙ ｋｎｏｗｎ ｆｒｏｍ ｔｈｅ ｐｏｐｕｌａｔｉｏｎｓ ｉｎ Ｔａｉｗａｎ， Ｃｈｉｎａ． Ｔｈｅ ｋａｒｙｏｔｙｐｅｓ ｏｆ Ｍ． ｃｏｒｄａｔａ ｒｅｓｅｍｂｌｅ ｔｈｏｓｅ ｒｅｐｏｒｔｅｄ ｆｏｒ ｏｔｈｅｒ Ｍｉｋａｎｉａ ｓｐｅｃｉｅｓ ｉｎ ｔｈｅ ｓｅｃｏｎｄａｒｙ ｃｏｎｓｔｒｉｃｔｉｏｎ ｏｆ ｔｈｅ ｆｉｒｓｔ ｃｈｒｏｍｏｓｏｍｅ ｐａｉｒ， ｗｈｉｃｈ ｃｏｕｌｄ ｂｅ ｃｏｎｓｉｄｅｒｅｄ ａ ｃｙｔｏｌｏｇｉｃａｌ ｍａｒｋｅｒ ｆｏｒ ｔｈｉｓ ｇｅｎｕｓ． Ｍｉｋａｎｉａ ｃｏｒｄａｔａ ａｎｄ Ｍ． ｍｉｃｒａｎｔｈａ ｈａｖｅ ｔｈｅ ｓａｍｅ ｃｈｒｏｍｏｓｏｍｅ ｎｕｍｂｅｒ ａｎｄ ｐｌｏｉｄｙ ｂｕｔ ｄｉｆｆｅｒｅｎｔ ｋａｒｙｏｔｙｐｉｃ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ． Ｈｏｗｅｖｅｒ， ｉｎｔｅｒｍｅｄｉａｔｅ ｋａｒｙｏｔｙｐｅ ｗａｓ ｎｏｔ ｆｏｕｎｄ ｗｉｔｈｉｎ ｐｏｐｕｌａｔｉｏｎｓ ｗｈｅｒｅ ｔｈｅ ｔｗｏ ｃａｍｅ ｉｎｔｏ ｃｌｏｓｅ ｃｏｎｔａｃｔ． Ｎｏ ｉｎｔｅｒｍｅｄｉａｔｅｓ ｂｅｔｗｅｅｎ ｔｈｅ ｔｗｏ ｓｐｅｃｉｅｓ ｗｅｒｅ ｏｂｓｅｒｖｅｄ ｄｕｒｉｎｇ ｆｉｅｌｄ ｗｏｒｋ， ａｎｄ ＩＳＳＲ ａｎａｌｙｓｅｓ ａｌｓｏ ｆａｉｌｅｄ ｔｏ ｄｅｔｅｃｔｅｄ ｈｙｂｒｉｄ ｉｎｄｉｖｉｄｕａｌｓ． Ｔｈｅｒｅｆｏｒｅ， ｔｈｅ ａｂｏｖｅ ｅｖｉｄｅｎｃｅ ｓｕｇｇｅｓｔ ｔｈａｔ ｔｈｅ ｓｕｃｃｅｓｓｆｕｌ ｉｎｖａｓｉｏｎ ｏｆ Ｍ． ｍｉｃｒａｎｔｈａ ｉｎ Ｃｈｉｎａ ｉｓ ｎｏｔ ａｓｓｏｃｉａｔｅｄ ｗｉｔｈ ｈｙｂｒｉｄｉｚａｔｉｏｎ ａｎｄ ｉｎｔｒｏｇｒｅｓｓｉｏｎ ｂｅｔｗｅｅｎ ｔｈｉｓ ｉｎｖａｓｉｖｅ ｓｐｅｃｉｅｓ Ｍ． ｃｏｒｄａｔａ ａｎｄ ｉｔｓ ｏｎｌｙ ｉｎｄｉｇｅｎｏｕｓ ｃｏｎｇｅｎｅｒ ｉｎ Ｃｈｉｎａ． Ａｆｔｅｒ ｃｏｍｐａｒｉｎｇ ｐａｓｔ ｈｅｒｂａｒｉｕｍ ｒｅｃｏｒｄｓ ｗｉｔｈ ｒｅｓｕｌｔｓ ｏｆ ｒｅｃｅｎｔ ｆｉｅｌｄ ｓｕｒｖｅｙｓ， ｗｅ ｆｏｕｎｄ ｔｈａｔ ｔｈｅ ｄｉｓｔｒｉｂｕｔｉｏｎ ｒａｎｇｅ ｏｆ Ｍ． ｃｏｒｄａｔａ ｉｎ Ｃｈｉｎａ ｈａｓ ｕｎｄｅｒｇｏｎｅ ａ ｇｒｅａｔ ｒｅｄｕｃｔｉｏｎ． Ｗｅ ｉｎｆｅｒ ｔｈａｔ ｈａｂｉｔａｔ ｄｅｓｔｒｕｃｔｉｏｎ ａｎｄ ｉｎｖａｓｉｏｎ ｏｆ Ｍ． ｍｉｃｒａｎｔｈａ ｍａｙ ｂｅ ｔｈｅ ｍａｉｎ ｃａｕｓｅｓ ｆｏｒ ｔｈｅ ｇｒａｄｕａｌ ｄｉｓａｐｐｅａｒａｎｃｅ ｏｆ Ｍ． ｃｏｒｄａｔａ ｉｎ Ｔａｉｗａｎ， Ｃｈｉｎａ． [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the efficacy of Mikania cordata leaf powder on non-specific immune response and disease resistance of Labeo rohita fingerlings against the Aphanomyces invadans infection. M. cordata extract was incorporated in the diets (at 0.0%, 1%, 2% and 3%) of L. rohita fingerlings (19±0.95g). Blood and serum sampling was carried out on 0th day, 14th day, 28th day and 42th day of feeding trials to determine NBT levels, myeloperoxidase activity, phagocytic activity and serum lysozyme activity, as compared to the control group. Fish were challenged with Aphanomyces invadans after 42 days and mortalities were recorded over 18 days post infection. The results revealed that fishes fed with Mikania cordata extract showed significant (p<0.05) increase in NBT levels, myeloperoxidase activity, phagocytic activity and serum lysozyme activity when compared to the control group. Dietary M. cordata extract of 2% showed significantly (p<0.05) higher protection relative percentage survival (RPS 71.06± 5.773%) from A. invadans infection than control. These results indicate that M. cordata leaf powder stimulates the non-specific immunity and makes L. rohita more resistant to fungal infection (A. invadans). [ABSTRACT FROM AUTHOR]

Mikania cordata, an invasive weed is becoming a problem in the secondary degraded forests and plantations of Bangladesh, not only competing with but also releasing allelochemicals to cultivated crops. Allelopathic effects of the leaves of M. cordata were investigated through an experiment in the green house of the Institute of Forestry and Environmental Sciences, University of Chittagong, Bangladesh. Five economically important agricultural crops ( Oryza sativa L., Triticum aestivum L., Vigna sinensis L., Abelmoschus esculentus L. and Amaranthus tricolor L.) and three forest crops ( Acacia auriculiformis A. Cunn. ex Benth. & Hook, Albizia procera (Roxb.) Benth., and Paraserianthes falcataria (L.) Nielson) were used as bioassay species. Experiments were conducted on trays at an average room temperature 27 °C. The effects of different concentrations of leaf extracts were compared to controls. Water soluble allelochemicals of M. c ordata inhibited the germination and initial growth of the tested agricultural and forest crops. Germination percent of forest crops declined with increasing concentration of extracts. The inhibitory effect on root elongation of forest crops was pronounced, whereas a stimulatory effect was found on P. falcataria up to a concentration of 25 %. Abelmoschus esculentus showed poor germination (%) and low shoot development (0.5 cm) and no development of taproot or lateral roots at treatment of 100 % concentration. The inhibitory effect was proportional to the concentrations of the extracts with higher concentrations producing stronger inhibitory effects. Lower concentrations showed some stimulatory effect. The inhibitory effect was pronounced in root and lateral root development rather than germination or shoot development of the crops. Mikania cordata should be eradicated for healthy growth and development of the forest and adjacent agricultural crops. [ABSTRACT FROM AUTHOR]

Mikania follows a sympodial dichotomy pattern of branching. Both stem (branches) and leaves give rise to new plants with relative ease. Internodes also root easily but do not give rise to new plants. Flower formation and seed germination are strongly influenced by light. Numerous seeds are produced but only few are filled; still fewer are the seeds that germinate. The period from early emergence to about the 3-leafed stage is most critical for survival of the new plant.

Effects of Mikania cordata root extract were investigated on stress-induced alterations in central neurotransmitters, viz., adrenaline (Ad), noradrenaline (NA), dopamine (DA) and 5-hydroxytryptamine (5-HT), and enzymatic activities of monoamine oxidase (MAO) in brain and succinic dehydrogenase (SDH) in brain and liver of mice. Both 5 h swimming and 24 h immobilization stress elicited a decrease in the levels of Ad and NA whereas they increased those of DA and 5-HT. Pretreatment with M. cordata root extract for 15 days prevented the decrement in Ad and NA and increment in 5-HT while the level of DA was further increased. There was a marked inhibition in brain MAO and stimulation in brain and liver SDH activities following both types of stress. The extract restored MAO activity towards normalization whereas it facilitated stress-induced changes in SDH activities. These dose-dependent biochemical responses may be the possible mechanism of anti-stress activity of this plant extract. [ABSTRACT FROM AUTHOR]

Mikania cordata, the only native congener of the invasive weed Mikania micrantha in China, is an ideal species for comparative study to reveal the invasion mechanism. However, its genome resources are lagging far behind its congener, which limits the comparative genomic analysis. Our goal is to characterize the genome of M. cordata by next-generation sequencing and propose a scheme for long-read genome sequencing. Previous studies have shown that the genomic resources of the host plant would be affected by the endophytic microbial DNA. An aseptic sample of M. cordata will ensure the proper genome in downstream analysis. Because endophytes are ubiquitous in the greenhouse-grown M. cordata, the in vitro culture with cefotaxime or timentin treatment was undertaken to obtain the aseptic plantlets. The in vivo mother plant and in vitro plantlets were used to survey the genome. The microbial contamination in M. cordata was recognized by blast search and eliminated from the raw reads. The decontaminated sequencing reads were used to predict the genome size, heterozygosity, and repetitive rate. The in vivo plant was so contaminated that microbes occupied substantial sequencing resources and misled the scaffold assembly. Compared with cefotaxime, treatment with timentin performed better in cultivating robust in vitro plantlets. The survey result from the in vitro plantlets was more accurate due to low levels of contamination. The genome size was estimated to be 1.80 Gb with 0.50% heterozygosity and 78.35% repetitive rate. Additionally, 289,831 SSRs were identified in the genome. The genome is heavily contaminated and repetitive; therefore, the in vitro culture technique and long-read sequencing technology are recommended to generate a high-quality and highly contiguous genome. [ABSTRACT FROM AUTHOR]