Sedge Research Articles

Alpine meadow degradation depresses soil nitrogen fixation by regulating plant functional groups and diazotrophic community composition

Biological nitrogen fixation (BNF), a function performed by diazotrophic microbes, plays an essential role in nitrogen (N) bioavailability in terrestrial ecosystems. However, little is known about the effects of meadow degradation on soil BNF and diazotrophic communities in alpine meadows. We investigated changes in soil BNF and their potential drivers in alpine meadows along a degradation gradient on the Tibetan Plateau (non-degraded, lightly degraded, moderately degraded, and severely degraded meadows) using real-time quantitative PCR and amplicon sequencing. Soil BNF rates decreased significantly along the meadow degradation gradient with a range of 17.34–79.84 nmol C2H4 g−1 dry soil d−1 across all sites. The highest BNF rate in the non-degraded meadow was 1.5–4.6-fold higher than that in the degraded meadows. The abundance and diversity of diazotrophs measured by nifH abundance and Shannon diversity was also decreased in the degraded meadows, accompanied by decreases in plant biomass, soil moisture, and nutrient content (C, N). Soil BNF rate was correlated with plant biomass, soil nutrient content, and diazotrophic abundance (including Nostoc, Scytonema, Rhodopseudomonas, and unidentified genera within the Rhizobiales and Proteobacteria). The community composition of diazotrophs differed markedly among sites with different levels of degradation, with both autotrophic (Cyanobacteria) and heterotrophic (Proteobacteria) diazotrophs contributing significantly to BNF. The plant functional groups, particularly the sedge family, were the primary drivers of soil BNF rates via mediating soil moisture, nutrient content (dissolved organic C and N), nifH gene abundance, and diazotrophic community composition. Our results reveal the main drivers of decreased BNF during alpine meadow degradation and emphasize the importance of plant functional groups in shaping the diazotrophic community and regulating the BNF rate. This information can be applied to the restoration of degraded meadow ecosystems.

Phytochemical profile, evaluation of antimicrobial and antioxidant activity in vitro of the hydroalcoholic extract of two species of the genus Cyperus (Cyperaceae)

Several factors contribute to the resistance of some pathogenic microorganisms and this fact requires the search for new therapeutic alternatives. The genus Cyperus (family Cyperaceae) groups species that present chemical compounds of pharmacological interest, mainly with antimicrobial action. Thus, the present work was carried out to investigate the antimicrobial activities, antioxidants and the phytochemical profile of Cyperus articulatus L. and Cyperus iria L. Hydroalcoholic extracts (1:1, v:v) of the aerial and underground parts of these species were used to analyze the total phenol content and to evaluate the in vitro antioxidant activity against the DPPH (2,2-diphenyl-1-picrylhydrazyl). The ethyl acetate and chloroform phases resulting from liquid-liquid partitioning of C. articulatus and C. iria extracts were evaluated in antimicrobial assays and subject to high performance liquid chromatography (HPLC-DAD) analysis. The chromatograms obtained by HPLC-DAD allowed us to identify four compounds: chlorogenic acid, catechin, quercetin, and quercitrin. The hydroalcoholic extracts of C. articulatus and C. iria showed a weak antioxidant activity with IC50 of 395.57 and 321.33 μg/mL (aerial parts), and 1,114.01 and 436.82 μg/mL (underground parts), respectively. Regarding antimicrobial activity, the chloroform phase of C. iria showed the best result at the concentration of only 31.2 µg/mL against the pathogens Candida albicans and Staphylococcus aureus. The ethyl acetate phases of the aerial parts of C. articulatus and C. iria did not show antimicrobial activity.

Impact of litter quality on the stability and storage of soil carbon in flooded wetlands

Context High inputs of plant litters and slow decomposition of soil organic carbon (SOC) influence the biogeochemical cycling of soil carbon in flooded wetlands. Aims To investigate the effects of different quality litter inputs on SOC stability and storage in flooded wetlands. Methods A 180-day microcosmic experiment to investigated the decomposition of litters of two dominant plants (Carex cinerascens Kukenth., CC; Cyperaceae family) and Triarrhena lutarioriparia L. Liu, TL; Poaceae family), in Poyang Lake Wetlands. Key results CC litters (high-quality, low lignin/N mass ratio) reduced gross content of SOC, but increased labile carbon and labile index (LI) of soils. In contrast, inputs of TL litters (low-quality, high lignin/N mass ratio) increased SOC gross content and recalcitrant carbon fractions of soils, but reduced soil labile carbons and LI. Significant effects of litters on SOC were not observed until ∼30 days indicating that the effects of litter inputs on soil carbon pools in flooded wetlands need time to be activated. CC and TL litters both increased the soil microbial biomass carbon (MBC) content. Soil MBC in CC treatments was significantly affected by the litter ash-free dry mass, while that in TL treatments was significantly affected by mass loss. Conclusions Litter quality may regulate the growth of soil MBC via different microbial growth strategies. Implications Our results suggest that inputs of high-quality litters can yield a high amount of labile carbon through stimulated microbial decomposition, leading to an overall loss of carbon. In contrast, inputs of low-quality litters can promote the microbial production of more recalcitrant carbons and increase soil carbon stability and carbon sequestration.

Musta in the Management of Atisara

Atisara diarrhoea a gastrointestinal tract disorder is very common and often seen in general practice. It is described as loose watery stools and most of the time can be controlled by simple fasting langhana. Ayurveda has described many formulations to control atisara. Musta an amazing Cyperus rotundus Linn belonging to the Cyperaceae family is useful in almost all types of atisara viz. ama pakwa alpadoshaja madhya doshaja samapittaja pittaja kaphaja atisara. In the present study we reviewed brihatrayi to analyze the mode of action and method of administration of musta in atisara.

Critical Review of Mustain the Management of Atisara

Atisara (Diarrhoea) is a most common disorder of Gastrointestinal tract and is very much commonly seen in general practice. Atisara is characterized by loose watery stools and most of the time will be controlled by simple fasting (Langhana). In classics we get many more formulations for management of Atisara. Musta, Cyperus rotundus Linn belonging to Cyperaceae family is one such wonderful drug which is explained as effective in almost all types viz, Ama, Pakwa, Alpadoshaja, Madhya doshaja, Samapittaja, Pittaja, KaphajaAtisara. Here an attempt is made to review Brihatrayi to analyse mode of action, method of administration of Musta in Atisara.

Systematic and Ecological-Cenotic Analysis of the Cyperaceae Family of the Chechen Republic

In this communication, a systematic and ecology-coenotical analysis of representatives of the Cyperaceae family of the Chechen Republic is given. A complete list of genera of the studied family of the Chechen Republic is specified. These studies were carried out based on processing herbarium materials and field observations of the authors. Representatives of Cyperaceae family of the Chechen Republic for the first time will be well studied.

Testing dental calculus as a means to determine paleodiet of extinct equid Merychippus sp.

During the Miocene Epoch, radiation of merychippine equids may have coincided with a transitional North American habitat of forests with patches of open grassland, and merychippine diet may reflect this diverse environment. Dental calculus on teeth of extinct herbivores like Merychippus can incorporate a long-term dietary record in the form of plant microfossils, such as phytoliths and fibers. In the present study, the purpose was to test dental calculus as a measure of paleodiet in equids by identifying and comparing Merychippus paleodiet constituents among preliminary sample groups. Calculus samples obtained from seven isolated Barstovian age Merychippus teeth from sites in Nebraska, Oregon, and Maryland, USA contained plant microfossils that were identified to categories based upon morphological characteristics. Grass silica short-cell phytoliths of BOP clade, C 3 -pathway subfamilies were most frequent, comprising 45–57% of all calculus samples. Microfossils from woody taxa were also present in all assemblages (18–29%). Softwood tracheary elements and sedge grass phytoliths (Family Cyperaceae) were significantly more frequent in Merychippus from the Maryland site. The combined presence of hardwood and grass microfossils from each Merychippus specimen indicates a mixed browse/grass diet that included C 3 grasses, supporting recent micro- and mesowear analyses. Some significant differences among these preliminary samples suggest that calculus is a valid means to compare diet among regions. Within a broader context, this type of study can generalize aspects of the Merychippus paleoenvironment and stands as an evaluation for using microfossils from dental calculus as a means for diet determination. • Microfossils from calculus on 7 Merychippus teeth are used to find evidence of diet. • Presence of pooid grass phytoliths indicates C 3 grasses in the environment. • Presence of hardwood microfossils suggests browse in diet. • Tracheid microfossils indicate possible dietary inclusion of softwood species. • Microfossils in Merychippus calculus are consistent with previous findings.

Silicon mobilisation by root-released carboxylates.

Plants have evolved numerous strategies to acquire poorly available nutrients from soil, including the release of carboxylates from their roots. Silicon (Si) release from mineral dissolution increases in the presence of chelating substances, and recent evidence shows that leaf [Si] increases markedly in old phosphorus (P)-depleted soils, where many species exhibit carboxylate-releasing strategies, compared with younger P-richer soils. Here, we propose that root-released carboxylates, and more generally rhizosphere processes, play an overlooked role in plant Si accumulation by increasing soil Si mobilisation from minerals. We suggest that Si mobilisation is costly in terms of carbon but becomes cheaper if those costs are already met to acquire poorly available P. Uptake of the mobilised Si by roots will then depend on whether they express Si transporters.

Grass-like plants release general volatile cues attractive for gravid Anopheles gambiae sensu stricto mosquitoes

BackgroundUnderstanding the ecology and behaviour of disease vectors, including the olfactory cues used to orient and select hosts and egg-laying sites, are essential for the development of novel, insecticide-free control tools. Selected graminoid plants have been shown to release volatile chemicals attracting malaria vectors; however, whether the attraction is selective to individual plants or more general across genera and families is still unclear.MethodsTo contribute to the current evidence, we implemented bioassays in two-port airflow olfactometers and in large field cages with four live graminoid plant species commonly found associated with malaria vector breeding sites in western Kenya: Cyperus rotundus and C. exaltatus of the Cyperaceae family, and Panicum repens and Cynodon dactylon of the Poaceae family. Additionally, we tested one Poaceae species, Cenchrus setaceus, not usually associated with water. The volatile compounds released in the headspace of the plants were identified using gas chromatography/mass spectrometry.ResultsAll five plants attracted gravid vectors, with the odds of a mosquito orienting towards the choice-chamber with the plant in an olfactometer being 2–5 times higher than when no plant was present. This attraction was maintained when tested with free-flying mosquitoes over a longer distance in large field cages, though at lower strength, with the odds of attracting a female 1.5–2.5 times higher when live plants were present than when only water was present in the trap. Cyperus rotundus, previously implicated in connection with an oviposition attractant, consistently elicited the strongest response from gravid vectors. Volatiles regularly detected were limonene, β-pinene, β-elemene and β-caryophyllene, among other common plant compounds previously described in association with odour-orientation of gravid and unfed malaria vectors.ConclusionsThe present study confirms that gravid Anopheles gambiae sensu stricto use chemical cues released from graminoid plants to orientate. These cues are released from a variety of graminoid plant species in both the Cyperaceae and Poaceae family. Given the general nature of these cues, it appears unlikely that they are exclusively used for the location of suitable oviposition sites. The utilization of these chemical cues for attract-and-kill trapping strategies must be explored under natural conditions to investigate their efficiency when in competition with complex interacting natural cues.Graphical abstract

Chemical Composition and Antiproliferative Activity of the Ethanolic Extract of Cyperus articulatus L. (Cyperaceae).

Cyperus articulatus L. (Priprioca) is a plant of the Cyperaceae family traditionally used in traditional medicine in the Amazon region. Studies of the essential oil of this species have identified many terpene compounds. However, little is known about the possible uses of solid waste generated by the extraction of essential oils. This study aimed to investigate the chemical composition of volatile compounds and to evaluate the antiproliferative activity of the ethanolic extract of solid residues generated by the extraction of the essential oil of C. articulatus L. rizhomes in experimental models in vitro using peritoneal macrophages of mice and human tumor cell lines. The analysis of the chemical composition of volatile compounds indicated the presence of sesquiterpenes and particularly sequiterpenic ketones as main constituents. The results showed that the treatment with ethanolic extract of C. articulatus L. reduced the activity of the enzyme arginase and proliferation of cancer cells (p < 0.0001). The extract also showed no cytotoxicity in macrophages in concentrations between 12.5; 25 and 50 mg/mL (p < 0.0001). The results indicated that the extract of C. articulatus L. exerts antiproliferative activity (p < 0.0001) with low toxicity on healthy cells in experimental models in vitro.

TLC and HPTLC Finger Printing Analysis of Cyperus rotundus (Linn.)

Cyperus rotundus (Linn.) is a versatile plant belonging to the family Cyperaceae, used in herbal medicines worldwide to cure various human ailments. The present study attempts to analyze the profiles of flavonoids in different extracts of C. rotundus with the help of thin-layer chromatography (TLC) and high-performance thin-layer chromatographic (HPTLC) fingerprint. Flower and stem extracts of C. rotundus were screens out with the help of TLC, and the Rf values were determined. HPTLC was used to quantify the flavonoid from flower extract of a plant at a 1.0 mg/mL concentration. It revealed the occurrence of flavonoids, especially quercetin in the ethanolic extract of C. rotundus flower, by using mobile phase toluene-ethyl acetate-formic acid (3:4:2.5 v/v), on a pre-coated plate of silica gel and quantified the amount of quercetin by densitometry absorbance mode at 257 nm. The limits of detection and quantification were 30.08 &amp; 91.16 ng/mL, and the relative standard deviation ranged between 1.03 to 1.48 for intra-day and inter-day for HPTLC. The calibration range was 200-700 ng per band (r2 = 0.99321). Quercetin quantity in the ethanolic extract of the flower was found to be 0.011 mg/mL of the extract with an average recovery of 99.01–100.00%. Such fingerprinting is valuable in quality control and checking adulterants of natural drugs. Therefore, it can be helpful for the assessment of different marketable pharmaceuticals preparations.

Eleocharis dulcis corm: phytochemicals, health benefits, processing and food products.

Eleocharis dulcis, an aquatic plant belonging to Cyperaceae family, is indigenous to Asia, and also occurs in tropical Africa and Australia. The edible corm part of E. dulcis is a commonly consumed aquatic vegetable with a planting area of 44.46 × 103 hm2 in China. This work aims to explore the potential of E. dulcis corm for use as a new food source for sufficient nutrients and health benefits by reviewing its nutrients, phytochemicals, functions, processing and food products. Eleocharis dulcis corm contains starches, dietary fibers, non-starch polysaccharides, proteins, amino acids, phenolics, sterols, puchiin, saponins, minerals and vitamins. Among them, phenolics including flavonoids and quinones could be the major bioconstituents that largely contribute to antioxidant, anti-inflammatory, antibacterial, antitumor, hepatoprotective, neuroprotective and hypolipidemic functions. Peel wastes of E. dulcis corm tend to be enriched in phenolics to a much higher extent than the edible pulp. Fresh-cut E. dulcis corm can be consumed as a ready-to-eat food or processed into juice for beverage production, and anti-browning processing is a key to prolonging shelf life. Present food products of E. dulcis corm are centered on various fruit and vegetable beverages, and suffer from single categories and inadequate development. In brief, underutilized E. dulcis corm possesses great potential for use as a new food source for sufficient nutrients and health benefits. © 2021 Society of Chemical Industry.

Ecologo-anatomic characteristics of the rare species Cladium mariscus (L.) Pohl

The anatomic structure of the vegetative organs of the rare and protected species Cladium mariscus (L.) Pohl is studied in order to expose its adaptation and resistance to the growth conditions. For the first time the microstructural organization of the root, rhizome and leaf was described. The vegetative organs of C. mariscus have a common plan of the anatomic structure similar to other species of the Cyperaceae family; along with this substantial differences were exposed in the structural organization of the lamina. There was exposed the combination of typical hygromorphic and specific xeromorphic adaptive indicators in the structure of the vegetative organs, caused by the peculiarities of the ecotope’s hydrological conditions.

Complete Chloroplast Genome Sequence and Comparative and Phylogenetic Analyses of the Cultivated Cyperus esculentus

Cyperus esculentus produces large amounts of oil as one of the main oil storage reserves in underground tubers, making this crop species not only a promising resource for edible oil and biofuel in food and chemical industry, but also a model system for studying oil accumulation in non-seed tissues. In this study, we determined the chloroplast genome sequence of the cultivated C. esculentus (var. sativus Boeckeler). The results showed that the complete chloroplast genome of C. esculentus was 186,255 bp in size, and possessed a typical quadripartite structure containing one large single copy (100,940 bp) region, one small single copy (10,439 bp) region, and a pair of inverted repeat regions of 37,438 bp in size. Sequence analyses indicated that the chloroplast genome encodes 141 genes, including 93 protein-coding genes, 40 transfer RNA genes, and 8 ribosomal RNA genes. We also identified 396 simple-sequence repeats and 49 long repeats, including 15 forward repeats and 34 palindromes within the chloroplast genome of C. esculentus. Most of these repeats were distributed in the noncoding regions. Whole chloroplast genome comparison with those of the other four Cyperus species indicated that both the large single copy and inverted repeat regions were more divergent than the small single copy region, with the highest variation found in the inverted repeat regions. In the phylogenetic trees based on the complete chloroplast genomes of 13 species, all five Cyperus species within the Cyperaceae formed a clade, and C. esculentus was evolutionarily more related to C. rotundus than to the other three Cyperus species. In summary, the chloroplast genome sequence of the cultivated C. esculentus provides a valuable genomic resource for species identification, evolution, and comparative genomic research on this crop species and other Cyperus species in the Cyperaceae family.

Phytochemical Screening and in vitro Antimicrobial Activity of Cyperus rotundus Leaf Extracts

Cyperus rotundus, a member of family Cyperaceae is a perennial, stoloniferous herb. The study investigated the secondary metabolites present in the leaf of Cyperus rotundus and antimicrobial activities of the hexane, ethyl acetate and methanol extracts. Phytochemical analysis revealed the presence of saponins, alkaloids, phenolic compounds, tannins, steroids, flavonoids, cardiac glycosides and terpenoids. The qualitative test of the extracts show the presence of steroid only in the hexane extract; flavonoid, cardiac glycoside in both the ethyl acetate and methanol extracts; saponin and tannin and phenolics in just the methanol extract. While alkaloid was present in all the extracts, terpenoid was absent in all. Antimicrobial activity of plant extracts were monitored using the agar disk-diffusion method against strains gram-positive bacterial: Staphylococcus aureus, Pseudomonas aeruginosa; and gram-negative bacteria: Escherichia coli, Salmonela typhi, and strains of fungi: Candida albicans and Aspergillus niger. The antimicrobial activity of the extracts was monitored at different concentrations of 50, 25, 12.5 and 6.25 mg/mL prepared from the stock concentration (100mg/mL) by serial dilution; with standard drugs: ciprofloxacin and fluconazole. The inhibition of the test organisms were concentration dependent. The methanol extract showed significantly higher Inhibition Zone (IZ) and Activity Index (AI) against the microbes at all concentrations compared to the ethyl acetate and hexane extracts due to the much phytochemicals (saponins, tanins, phenols, flavonoids, cardiac glycocides and alkaloids) found present in its extract. The overall study results signify the potential of Cyperus rotundus as a source of therapeutic agents. The methanol extract showed the best activity against both bacterial and fungal pathogens at the highest concentration of 100 mg/mL, especially the most susceptible bacteria: Staphylococcus aureus (IZ of 25.0±1.5; AI of 0.96) and Candida albicans (IZ of 25.5±0.5; AI of 0.91). At MIC, MBC and MFC of 6.25 mg/mL and 12.5 mg/mL, the plant extracts showed effective bactericidal and fungicidal effect against the test microbes.

Systematic treatment of morphological fruit types in plants of the class Liliopsida of the flora of Ukraine

In this review, the scope of morphological diversity of fruits within the class Liliopsida belonging to the flora of Ukraine compared to the world flora diversity was analyzed. For the first time, the taxonomic diversity of monocot plants of the flora of Ukraine was analyzed, which includes 235 genera and about 1050 species, and the distribution of fruit types in the largest monocot families revealed. It was found that among monocot plants of the world flora, as also of the Ukrainian flora, more than 70% of generic and species diversity is taken up by the Orchidaceae, Poaceae, and Cyperaceae families having dry uniform fruits: inferior capsule (Orchidaceae) and one-seeded enveloped fruit (Poaceae and Cyperaceae). An annotated list of morphological fruit types was compiled for all 38 families of the natural and cultural flora of monocot plants of Ukraine. Among 12 families of the subclass Alismatidae, apocarpous polymerous or trimerous fruits, mostly with one-seeded fruitlets, occur in six families (Alismataceae, Butomaceae, Potamogetonaceae, Ruppiaceae, Scheuchzeriaceae, Zannichelliaceae). In 12 of 16 families of the subclass Liliidae, trimerous capsules are the most common (Agapanthaceae, Agavaceae, Alliaceae, Amaryllidaceae, Asphodelaceae, Colchicaceae, Hemerocallidacae, Hyacinthaceae, Iridaceae, Liliасеае, Melanthiaceae, Orchidaceae), while in six families berry-like fruit occurs in all members or in the single genus (Asparagaceae, Ruscaceae, Dioscoreaceae, Melanthiaceae (Paris), Liliасеае (Streptopus), Smilacaceae). Among 10 families of the subclass Commelinidae, in four families superior dry one-seeded fruits occur (Cyperaceae, Poaceae, Sparganiaceae, Typhaceae), while another four families have trimerous capsules (Cannaceae, Commelinaceae, Juncaceae, Pontederiaceae). In general, the most typical fruit on the familial taxonomical level is the capsule (17 families), berries occur in 10 families, aggregate fruits and one-seeded fruits are represented each in seven families, while the rarest fruit type is the schizocarp (Juncaginaceae). No monomerous follicles, poricide and operculate capsules, winged fruits and loments were found. The most controversial fruit types are found in two groups of families, for both of them the problem is the gynoecium type. These are families with one-seeded fruit (Аrасеае (Lemna), Cyperaceae, Hydrocharitaceae (Najas), Poaceae, Sparganiaceae, Typhaceae, Zosteraceae) and families with initial carpel fusion (Hydrocharitaceae (Stratiotes), Juncaginaceae, Melanthiaceae (Veratrum), Scheuchzeriaceae, Tofieldiaceae). As a result of our work, the key and the most relevant areas of carpological studies in Ukraine were defined, particularly, unifying the terminology, examination of the anatomical structure of the pericarp, revealing of the evolutionary and ecological aspects of fruit morphology.

Novel species of Alternaria section Nimbya from Iran as revealed by morphological and molecular data

ABSTRACT In this study, the diversity of Alternaria species in section Nimbya associated with symptomatic plants in the Cyperaceae and Juncaceae families was assessed. Multilocus sequence analyses of the rDNA internal transcribed spacer (ITS) region and parts of Alternaria major allergen (Alt a 1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), second largest subunit of RNA polymerase II (RPB2), and translation elongation factor 1-alpha (TEF1) genes revealed the presence of two previously known species, A. scirpivora and A. caricicola, and three new species, which are described here as A. cypericola, sp. nov., A. heyranica, sp. nov., and A. junci-acuti, sp. nov. These new species were characterized morphologically with respect to the dimensions of conidia, the number of pseudosepta in mature conidia, and the type of conidium apical beak. According to the results of phylogenetic analyses, the presence of long, filiform true beak is not a reliable morphological indicator for grouping species in sections Alternantherae and Nimbya and phylogenetic species recognition should be used. All identified species were described, illustrated, and their morphology and phylogenetic relationships with other species in Alternaria section Nimbya were discussed.

Meiotic analysis in some species of family Cyperaceae from North India

The present study reports the chromosome counts and meiotic analysis including microsporogenesis and pollen fertility in 7 species in the family Cyperaceae from North Indian states. We here add the chromosome record for four species of Cyperaceae. During the present investigation, in some meiotic cells of Cyperus difformis and Isolepis setacea, chromatin threads were found which were typical for the species with inverted meiosis. So present investigation gives the idea of the presence of inverted meiosis in these two genera. Pseudomonad formation, the special feature of the family Cyperaceae where three nuclei out of four degenerate and gives the final product of one pollen per PMC. The course of meiosis in most of the accessions was observed to be regular except for some individuals of Cyperus paniceus, Scirpus mucronatua and Isolepis setacea which showed certain meiotic abnormalities in meiocytes involving cytomixis, chromatin stickiness, chromatin bridges, lagging chromosomes, and interchromosomal connections of bivalents. Being a holocentric family agmatoploidy, symploidy, and polyploidy can play important role in karyotype evolution. The Family shows considerable heterogeneity in chromosome numbers ranging from n = 2 to 60. The family exhibits several base numbers (x=5-14, 16, 20-23, 26, 27, 29, 30, 36, 38, 60) and x=5 is regarded as the most relevant base number for the family. Other base numbers have supposed to be secondarily derived from the ancestral number x=5.

Cyperaceae in a data‐rich era: New evolutionary insights from solid frameworks

Cyperaceae in a data‐rich era: New evolutionary insights from solid frameworks

Screening of natural compounds from Cyperus rotundus Linn against SARS-CoV-2 main protease (Mpro): An integrated computational approach

Coronavirus disease 2019 (COVID-19) is a viral respiratory disease that has been spreading across the globe. The World Health Organization (WHO) declared it as a public health emergency. The treatment of COVID-19 has been hampered due to the lack of effective therapeutic efforts. Main Protease (Mpro) is a key enzyme in the viral replication cycle and its non-specificity to human protease makes it a potential drug target. Cyperus rotundus Linn, which belongs to the Cyperaceae family, is a traditional herbal medicine that has been widely studied for its antiviral properties. In this study, a computational approach was used to screen natural compounds from C. rotundus Linn using BIOVIA Discovery Suite and novel potential molecules against Mpro of SARS-CoV-2 were predicted. Molecular docking was performed using LibDock protocol and selected ligands were further subjected to docking analysis by CDOCKER. The docking scores of the selected ligands were compared with standard antiretroviral drugs such as lopinavir and ritonavir to assess their binding potentials. Interaction pharmacophore analysis was then performed for the compounds exhibiting good binding scores to evaluate their protein–ligand interactions. The selected protein–ligand complexes were subjected to molecular dynamics simulation for 50 ns. Results of binding free energy analysis revealed that two compounds—β-amyrin and stigmasta-5,22-dien-3-ol—exhibited the best binding interactions and stability. Finally, absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies were performed to understand the pharmacokinetic properties and safety profile of the compounds. The overall results indicate that the phytochemicals from Cyperus rotundus Linn, namely β-amyrin and stigmasta-5,22-dien-3-ol, can be screened as potential inhibitors of SARS-CoV-2 Mpro.