Acanthospermum Australe Research Articles

The use of essential oils as an alternative for the control of Tetranychus urticae (Acari: Tetranychidae)

Considering that the use of essential oils is a promising technique and a valuable alternative in the control of unwanted organisms, this study aimed to chemically characterize the essential oil of Acanthospermum australe (Loefl.) O. Kunze (Asteraceae) through gas chromatography, as well as to evaluate the repellent and acaricidal effect of the essential oils from A. australe and Baccharis psiadioides (Less.) Joch.Müll (Asteraceae) against Tetranychus urticae Koch (Tetranychidae). For the repellency test, concentrations of 0.25, 0.5 and 1% were used for both oils, and concentrations of 10 μL/L(air) and 20 μL/L(air) to evaluate acaricidal effects. Eight compounds were identified in the essential oil of A. australe, with thymyl isobutyrate (63.4%) being the major compound, followed by thymol (13.4%) and thymyl 2-methylbutyrate (4.96%). The results demonstrated higher repellency to the essential oil of A. australe at a concentration of 0.5%, followed by B. psiadioides at a concentration of 1%. The mortality rate of TSSM exceeds 90% when exposed to both tested concentrations of the essential oil of A. australe proving effective in both cases.

Synergistic Antimicrobial Activity of Biogenic Silver Nanoparticles and Acanthospermum australe Essential Oil against Skin Infection Pathogens.

In response to the steady increase in antimicrobial-resistant strains, the World Health Organisation has emphasised the need to investigate new antimicrobial agents and alternative therapies that improve the spectrum of activity and reduce the dose required, thus improving safety. This study focused on the characterisation of Acanthospermum australe essential oil and green-synthesis silver nanoparticles (AgNP), evaluating their cytotoxicity in human cells, antimicrobial activity and synergistic effect against pathogens causing skin infections. The main components of the essential oil were germacrene A (24.07%), γ-cadinene (21.47%) and trans-caryophyllene (14.97%). Spherical AgNP with a diameter of 15 ± 3 nm were synthesised. The essential oil showed antimicrobial activity against dermatophytes and Malassezia globosa, while AgNP were found to be active against bacteria, yeasts and dermatophytes. Both compounds were found to be primarily non-cytotoxic at the concentrations required to inhibit microbial growth. Furthermore, the combined use of essential oil and AgNP showed a synergistic antimicrobial effect against dermatophytes and M. globosa. In conclusion, the results suggest that the combined use of bioactive compounds from natural sources, such as essential oil and biogenic AgNP, has the potential to improve antimicrobial efficacy against specific skin pathogens, particularly Microsporum canis, Nannizzia gypsea and M. globosa.

Antiviral activity of two Acanthospermum species against herpes simplex virus 1

Ethnopharmacological relevanceAcanthospermum species are used in traditional medicine for treating various pathologies, including bacterial and viral infections. In a screening study, we identified the activity of the ethanolic extracts of Acanthospermum australe and Acanthospermum hispidum against herpes simplex virus 1 (HSV-1). Aim of the studyIn this work, we analyzed the phytochemical profile and antiviral activity of the chemical fractionation products of Acanthospermum australe and Acanthospermum hispidum. Additionally, we identified the effect of these fractions on different steps of the viral cycle. Materials and methodsAcanthospermum samples were extracted with methanol and further partitioned with solvents of increasing polarities: hexane, chloroform, ethyl acetate, and butanol. Cytotoxicity and antiviral activity were analyzed for each fraction. The active fractions were tested to identify the virucidal effect and the inhibition of virus–cell binding. Further, the effect of these fractions on the replication and viral gene was quantitated by qPCR, and the expression of gD protein was evaluated by Western blot. ResultsThe chloroform and hexane fractions of Acanthospermum hispidum and Acanthospermum australe showed dose-dependent antiviral activity. The chloroform fraction inhibited the virus–cell binding and virus cycle in a post-entry mechanism by decreasing replication and the expression of early and late viral genes. The hexane fraction did not inhibit virus binding; however, it showed antiviral activity in post-entry events by inhibiting the immediate-early, early, and late genes. We identified in both species the presence of 3.6-dimetoxiapigenin, axillarin, and penduletin in the chloroform fraction and methyl-(Z,Z)-9,12-octadecadienoate and phytol in the hexane fraction. ConclusionsAcanthospermum hispidum and Acanthospermum australe possess antiviral activity against HSV-1 and affect different steps of the viral cycle. These characteristics make them good candidates for developing phytotherapeutic products against HSV-1.

Acanthospermum australe (spiny-bur)

This datasheet on Acanthospermum australe covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

Sowing depth and light intensity on the emergence and development of weeds

Weeds are one of the ecological factors that directly affect agricultural costs. Thus, understanding the emergence and development of these species is essential for the decision-making on weed control strategies. This study aims to evaluate the effect of different sowing depths and luminous intensities under field conditions on the emergence and development of the Acanthospermum australe (Loefl.) Kuntze and Ipomoea grandifolia (Dammer) O'Donell. Each species constituted one experiment, and the completely randomized design with four repetitions was adopted. The treatments were arranged in a 6 x 4 factorial scheme, with six sowing depths (0.5; 1.0; 2.0; 4.0; 8.0; and 12.0 cm) associated with four luminous intensities (100%, 70%, 50%, and 30% sunlight) obtained using shade cloths. The emergence of seedlings was evaluated daily to obtain the emergence and the emergence speed index. Plant height(length), the period until flower induction, and the dry matter of plants during flowering were also analyzed. A. australe and I. grandifolia emerge under the luminous intensities of 100, 70, 50, and 30% of solar radiation and in sowings depths up to 12.0 cm. Nevertheless, A. australe is the only one affected by luminous intensity, sowing depth, and the interaction between both factors in all the analyzes conducted. Luminous intensity reduction leads to lower development of I. grandifolia .

Antimicrobial and cytotoxic activity of green synthesis silver nanoparticles targeting skin and soft tissue infectious agents

Combining traditional medicine with nanotechnology therefore opens the door to innovative strategies for treating skin and soft tissue infections (SSTIs) and also contributes to the fight against the rise of antimicrobial resistance. Acanthospermum australe (Loefl.) Kuntze is a medicinal plant used by indigenous peoples in northeastern Argentina to treat SSTIs. Spherical and stable silver nanoparticles (AgNPs) of 14 ± 2 nm were synthesized from the aqueous extract of A. australe and silver nitrate. The antimicrobial activity against main species causing SSTIs and cytotoxicity on peripheral blood mononuclear cells of AgNP solution and its synthesis components were evaluated. Compared to its synthesis components, AgNP solution showed greater antimicrobial activity and lower cytotoxicity. The antimicrobial activity of AgNPs was due to the silver and not to the metabolites of the aqueous extract present on the surface of the nanoparticles. The plant extract played an important role in the formation of stable AgNPs and acted as a modulator of cytotoxic and immune responses.

Host weed species range of Meloidogyne ethiopica whitehead (Tylenchida: Meloidogynidae) found in Brazil

Meloidogyne ethiopica is considered to be one of the most economically important emerging nematode species, reported to cause crop losses to several hosts worldwide. The significance of this species is due to its high virulence and degree of polyphagia, in addition to persisting on weed hosts within agricultural fields. This study evaluated the host status of 36 different weed species, confirming the polyphagia habit of M. ethiopica and indicating which plant species may be alternative hosts for this plant nematode. Weed species were inoculated with 5000 eggs and second-stage juveniles (J2) of M. ethiopica, with gall index (GI), nematode/g root (Nem/g), and reproduction factor (RF) value determined following 60 days post inoculation. The data obtained indicate that many weed species may be excellent hosts for M. ethiopica. Plants deemed susceptible (RF ≥ 1.0) were: Acanthospermum australe, Amaranthus deflexus, A. hybridus, A. spinosus, A. viridis, Bidens pilosa, B. subalternans, Cardiospermum halicacabum, Commelina benghalensis, Cynodon dactylon, Euphorbia heterophylla, Galinsoga parviflora, Ipomoea grandifolia, I. nil, I. purpurea, Leonurus sibiricus, Nicandra physaloides, Oxalis corniculata, Portulaca oleracea, Raphanus raphanistrum, Sida rhombifolia, Solanum americanum, S. pseudocapsicum, S. sisymbriifolium, Sonchus oleraceus and Talinum paniculatum, representing 72.2% of the species assessed. The species Conyza bonariensis, Cyperus rotundus, Digitaria horizontalis, D. insularis, Echinochloa colonum, Eleusine indica, Lolium multiflorum, Polygonum hydropiperoides, Rhynchelytrum repens and Senecio brasiliensis were resistant to M. ethiopica (RF < 1.0). Based on the new host records presented, it is vital that control of weed species within agricultural fields are considered as part of effective management of M. ethiopica.

Seeds of weeds as an alternative host of phytopathogens

ABSTRACT: Weeds compete with agricultural crops for water, light, nutrients and space, besides having an extensive seed bank. However, another aspect to be considered relates to few studies pointing out weeds as hosts of phytopathogenic fungi. Many fungi, the main cause of diseases in plants, are known to use seeds as an efficient means of survival and dispersal. The objective of this work was to evaluate the health of weed seeds and the pathogenicity of fungi associated to plants of agricultural importance. The seeds were collected manually in Cerrado areas located in the municipality of Gurupi, Tocatins, Brazil. The blotter test method was used to evaluate seed health. The incidence of fungi was evaluated through an individual analysis of seeds using a stereoscopic and an optical microscope. The pathogenicity of fungi from weed seeds was evaluated by inoculation in plants of agronomic interest and, when pathogenic, we inoculated them in the host plant of the fungus. Weed seeds have been identified in fungi of the genus Alternaria, Aspergillus, Bipolaris, Cladosporium, Curvularia, Fusarium, Nigrospora, Papularia, Rhizopus and Pythium. The seeds of Acanthospermum australe, Bidens pilosa, Cenchrus echinatus, Digitaria horizontalis, Echinochloa crus-pavonis, Eleusine indica, Ipomoea sp., Pennisetum setosum, Sida rhombifolia, Spermacoce latifolia, Tridax procumbens and Vernonia polyanthes carry and disseminate fungi that, once inoculated, cause infection in plants of agricultural importance, such as Oryza sativa, Phaseolus vulgaris, Vigna unguiculata, Zea mays and Glycine max.

Effectiveness of aqueous and hydroalcoholic extracts of Acanthospermum australe (Loefl.) Kuntze against diarrhea-inducing bacteria.

Leaves and roots of Acanthospermum australe (Asteraceae) have been used in Brazilian folk medicine for the treatment of various ailments including diarrhea, skin diseases, blennorrhagia, dyspepsia, parasitic worms and malaria. The aim of study was to characterize the chemical profiles of the aqueous and hydroalcoholic extracts of leaves and roots of A. australe, and to evaluate their antimicrobial activities against diarrhea-inducing bacteria (Enterococcus faecalis, Shigella dysenteriae and Yersinia enterocolitica), as well as their cytotoxic properties. Aqueous leaf extracts were obtained by infusion, while aqueous root extracts were obtained by decoction. The hydroalcoholic leaf and root extracts were prepared by maceration in 90% ethanol for 3 days. Antimicrobial activity was assessed using standard techniques and cytotoxicity was evaluated using Chinese hamster ovary cells CHO-K1. Chemical analysis revealed the presence of tannins, flavonoids, saponins and phenolic compounds in the extracts. Although root extracts were not effective against E. faecalis, leaf extracts at concentrations of 20 mg/mL exhibited bactericidal activities against this microorganism. The hydroalcoholic root extract was unique in presenting a bactericidal effect against S. dysenteriae. None of the extracts showed bacteriostatic or bactericidal activities against Y. enterocolitica. The results presented herein demonstrate that the Gram-positive E. faecalis and the Gram-negative S. dysenteriae were susceptible to A. australe extracts, although bacteriostatic/bactericidal activities were only observed at concentrations considered too high for clinical application. Our results support the ethnopharmacological use of A. australe in the treatment of gastrointestinal disorders, particularly diarrhea caused by infectious bacteria, although further studies are required to determine the anti-diarrhea effects and the toxicities of the extracts in vivo.

Flora da Bahia: Asteraceae – Tribo Millerieae

The taxonomic treatment of the tribe Millerieae of Bahia state, Brazil, is presented. The tribe is represented by five genera in Bahia: Acanthospermum (2 species), Galinsoga (2), Ichthyothere (2), Melampodium (2) and Tridax (1). Ichthyothere hirsuta is a new record in the state. Acanthospermum australe, A. hispidum, Ichthyothere terminalis and Tridax procumbens are widely distributed in Bahia and, although ruderal, are still inaccurately identified in herbaria. Descriptions, identification keys, illustrations, comments on taxonomy and geographical distribution are provided for taxa.

Biological activities of ophiobolin K and 6-epi-ophiobolin K produced by the endophytic fungus Aspergillus calidoustus

Endophytic fungi represent ubiquitous microbial organisms able to live in the tissues of different plants around the world and represent a prolific source of bioactive metabolites. In the present study, the endophytic fungus Aspergillus calidoustus was isolated from the medicinal plant Acanthospermum australe (Asteraceae), and identified using molecular, physiological and morphological methods. A methylene chloride crude extract of A. calidoustus has been produced and subjected to antifungal bioassay-directed fractionation which resulted in the isolation of the two bioactive compounds: ophiobolin K and 6-epi-ophiobolin K. These pure compounds displayed antifungal activity against fungal plant pathogens, protozoal activity against Trypanosoma cruzi, and cytotoxic activity against human tumoral cell lines. The results show that A. calidoustus was able to produce the antifungal and cytotoxic metabolites ophiobolin K and 6-epi-ophiobolin K, which may help the fungus to colonise and occupy the substratum as well as survive in natural environments.

Chemical composition and antimicrobial activity of essential oil from Brazilian plants Acanthospermum australe, Calea fruticosa and Mikania glauca.

The essential oils of leaves of Acanthospermum australe, Calea fruticosa and Mikania glauca (Asteraceae) from southeastern Brazil were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). Oxygenated sesquiterpenes were predominant in C. fruticosa (47.8%) whereas sesquiterpenes hydrocarbons constituents predominated in A. australe (85.1%) and M. glauca (63.3%) oils. Caryophyllene oxide, α-cadinol and selin-11-en-4-α-ol were the most abundant components in C. fruticosa. Germacrene D, (E)-caryophyllene and bicyclogermacrene were the major components observed in the essential oil obtained from the leaves of A. australe and M. glauca. The antimicrobial capacity of the oils was tested. The results showed that the oils have antimicrobial activity against Gram-negative bacteria and Candida glabrata, with minimal inhibitory concentration (MIC) values between 50 and 1000 µg/ml. Key words: Asteraceae, essential oil, gas chromatography-mass spectrometry (GC-MS), antimicrobial activity, Brazilian flora.

Preliminary phytochemical screening of methanolic–aqua extract of Acanthospermum australe leaves.

The study was carried to analyze the phytochemical constituents of the Acanthospermum australe. The plant samples were extracted using methanol and water in the ratio of 9:1. From the study the extract of Acanthospermum australe was found to contain tannins, saponins, terpenoids, phenols, alkaloids, steroidal rings but steroids and flavonoids were found to be absent. The presence of these important phytochemicals in the plant roots is a scientific justification of the plant use in the traditional treatment against various diseases affecting humans and animals. However, more research needs to be done to identify the specific compounds, their structural formulas and contribution towards medicinal values of the plant.

Macro and microscopical identification of two Acanthospermum medicinal plants

Acanthospermum hispidum and Acanthospermum australe (Asteraceae) are widely distributed in arid regions, in northeastern Brazil, and the first specie is used in folk medicine as anti‑asthmatic while the second specie as antiseptic, anti-inflammatory and diuretic. They are often confounded and used indifferently for the same medicinal purposes due to both having similar morphological characteristics. The aim of this work was to carry out a macro and microscopical investigation to characterize the vegetative organs, including the macerate of both species. The plant material was collected, fixed and processed according to usual light microscopy techniques. A short-petiole in A. hispidum is a diagnostic trait that distinguish it from A. australe. Types of glandular trichomes can distinguish these two species. The different types of xylem vessels found in root, stem and leaf of both species identify the presence of one of them into raw drug. These findings will be useful in establishing pharmacognostic and phytochemical standards for identification, as well as assessment of accuracy to avoid contamination and insure quality control, which definitely is gaining relevance in plant drug research and establishment of plant monograph. Key words: Acanthospermum hispidum, Acanthospermum austral, anti-asthmatic, macerate, traditional medicine, folk medicine, Brazil.

In vitro effect of Acanthospermum australe (Asteraceae) extracts on Acanthamoeba polyphaga trophozoites

Acanthamoeba is a free-living protozoan widely distributed in the environment, occurring in vegetative trophozoite and resistance cyst stages during its life cycle. It constitutes an etiological agent of Acanthamoeba keratitis, a disease that may cause severe ocular inflammation and blindness. New drugs can be developed from molecules found in plants and thus help in its difficult treatment. Acanthospermum australe (Asteraceae), a plant used in folk medicine, had its effect tested on Acanthamoeba polyphaga. Aqueous and ethanolic extracts of A. austral were obtained from aerial parts for infusion and static maceration, respectively. Concentrations of 10, 5, 2.5, 1.25 and 0.625 mg/ml of the extract were tested against Acanthamoeba polyphaga trophozoites. The cytotoxic effect of the extracts was tested in mammalian cells using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. RESULTS: The 10 mg/ml concentration of ethanolic extract was lethal to 100% of the A. polyphaga trophozoites in 24 h and both extracts presented cytotoxic effect against mammalian cells. These findings suggest that the A. austral ethanolic extract may have compounds with relevance to the development of new amoebicidal drugs.

In vitro antiviral activity from Acanthospermum australe on herpesvirus and poliovirus

Context: The Asteraceae family has been of interest to researchers due to the presence of polyphenolic compounds, mainly flavonoids, which demonstrated antiviral activity.Objective: The hydroethanol extract of the aerial parts of Acanthospermum australe (Loefl.) Kuntze (Asteraceae) and its fractions, were evaluated in vitro for their potential cytotoxic and antiviral activity against bovine herpesvirus and human poliovirus.Materials and methods: The sulforhodamine B colorimetric assay were used to evaluate the capacity of the hydroethanol extract and fractions to inhibit the lytic activity of herpes and poliovirus in infected cell cultures and their influence on the viability of uninfected cell cultures.Results and discussion: A progressive increase in the antiviral effect against herpesvirus was observed in the course of the purification process of the extract. The hydroethanol extract had a 50% antiviral effective concentration (EC50) at 70 μg/mL and 36 μg/mL for herpes and poliovirus, respectively, and it exhibited no cytotoxicity. The fractions F3 (dichloromethane) and F4 (dichloromethane: ethyl acetate (1:1 v/v)) both showed EC50 at 6.25 μg/mL against herpesvirus, and these fractions showed cytotoxic concentrations (CC50) at 12.7 and 11.7 μg/mL, respectively. These fractions had no effect against poliovirus in the concentrations tested. From the bioactive F3, a diterpene lactone (acanthoaustralide-1-O-acetate) was isolated at a concentration of 0.5% and from F4 two flavonoids (quercetin and chrysosplenol D) were isolated at concentrations of 0.14 and 0.24%, respectively.Conclusion: The present study reports for the first time the antiviral activity of extracts and fractions from A. australe aerial parts.

Melampolides from Argentinean Acanthospermum australe

The investigation of the ethanol extract of Acanthospermum australe, collected in the province of Misiones, Argentina, yielded eight melampolides ( 1– 8) of the acanthospermal type. Two of them, 8β-hydroxy-9α-(2-methylbutyryloxy)-14-oxo-acanthospermolide ( 3) and 9α-hydroxy-8β-(2-methylbutyryloxy)-14-oxo-acanthospermolide ( 7) are new compounds. Two other compounds ( 4 and 8) have been previously reported, and the NMR data of 4 are corrected. Compounds 1, 2, 5 and 6 have not been previously reported, but are probably artifacts formed during extraction. Compounds 3, 6 and 7 showed slight antibiotic activity against Gram-positive bacteria.

Morfologia de plântulas e estádios juvenis de espécies invasoras

The morphology of 20 species of weeds that occur in the most common crops in Maringá, Paraná State, Brazil and adjacent regions were described at early developmental stages, in order to identify the species in the field and provide information for taxonomic and ecological works. Sixteen species featured epigeal-foliaceous seedlings. The seedling in Cardiospermum halicacabum is epigeal-fleshy; in Cenchrus echinatus and Digitaria horizontalis it is hypogeal and in Commelina virginica is epigeal-cryptocotyledonar. The differentiation of the first eophyll occurred within ten (Digitaria horizontalis) to 35 days (Bidens pilosa) and the first metaphyll appeared within 22 (Commelina virginica) to 49 days (Acanthospermum australe). The number of eophylls varied from one to four, and the phyllotaxis varied from alternate to opposite.

Acanthospermum australe é hospedeiro alternativo de Thanatephorus cucumeris, agente causal da mela do feijoeiro

Acanthospermum australe, a frequently weed infesting bean crops in the State of Goias, Brazil, was found infected by T. cucumeris under natural field conditions. Plants were severely affected and may be an important reservoir of inoculum for infection of cultivated crops. Pathogenicity of T. cucumeris in both A. australe and Phaseolus vulgaris was confirmed by Koch´s postulates.

Atribuição dos deslocamentos químicos dos átomos de ¹H e 13C do acetato de acantoaustralida

Do extrato hidroetanólico das partes aéreas de Acanthospermum australe (Asteraceae) foram identificados uma lactona diterpênica, o acetato de acantoaustralida (1) e dois flavonoides: quercetina (2) e crisosplenol D (3). As estruturas foram identificadas através de técnicas espectroscópicas de RMN de ¹H e 13C, gHSQC, gHMBC, TOCSY, gNOESY, EM e pela comparação com dados da literatura.