Conyza canadensis: Green Extraction Method of Bioactive Compounds and Evaluation of Their Antifungal Activity

Abstract

Synthetic fungicides are a common treatment for post-harvest diseases in fruits, although demand is increasing for alternatives such as biopesticides. The aim of this work was to investigate the presence of naturally occurring antifungal compounds in Brazilian specimens of the weed Conyza canadensis. Two compounds [(4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone] were isolated and their antifungal activities were evaluated against eight postharvest disease fungi. Aspergillus niger, Cladosporium sp., and Penicillium digitatum proved susceptible to the treatment (minimum inhibitory concentrations varying from 32 to 64 µg mL -1 ). These fungi are common postharvest pathogens of fruits and vegetables, causing rots and secreting mycotoxins. A green and sustainable extraction method employing pressurized hot water was developed and optimized (100 °C, 4 × 1 min cycles). Yields of 1.46 and 0.24 mg g -1 were obtained for (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone, respectively. The extract could be applied directly to fruits and vegetables in postharvest treatments.

Bioactive compound isolated from Conyza canadensis combined with physical treatments for the control of green mould in Orange

“…The isolated substance, (4Z)-lachnophyllum lactone (LACH), was characterized as described by Porto et al (2017). To confirm the structure of this compound, 1 H and 13 C nuclear magnetic resonance F I G U R E 1 Bioactive substance isolated from Conyza canadensis (4Z)-lachnophyllum lactone (LACH) (NMR) spectra were obtained using either a Bruker AVANCE 400 MHz spectrometer or a Bruker AVANCE 500 MHz spectrometer and CDCl 3 as solvent.…”

“…Queiroz et al (2012) performed the systematic fractionation guided by bioassays using extract of C. canadensis and identified three substances with antifungal activity among them (4Z)-lachnophyllum lactone (LACH) (Figure 1). According to Porto et al (2017), this substance showed significant in vitro activity against P. digitatum.…”

Antimicrobial potential, phytochemical profile, cytotoxic and genotoxic screening of Sedum praealtum A. DC. (balsam)

“…The dispersions were filtered and analyzed by GC-MS (Aligent 5975C TAD Series GC/MSD System,©Aligent Technologies, Inc., CA, USA) using the following chromatographic conditions: (i) Sample: injected volume of 2.0 μl; (ii) Column: HP-5MS, 5% diphenyl, 95% dimethylpolysiloxane (30 m × 0.25 mm × 0.25 μm); (iii) Drag gas: He (99.9999) → 1 ml/min; (iv) Injector: 280°C, Split 1:10 (leaf and root) and 1:1 (stem); (v) Oven: 50°C (2 min) → 250°C (5°C/1 min); 250°C (10 min); and (vi) Detector: Linear quadrupole mass spectrometer, Ionization source (impact by electrons → 70 eV), Scan mode (0.5 s/scan), Mass range ], Line transfer (280°C) and Filament (off at 7.0 min). The Mass Spectral Database (NIST 11) was used to identify compounds detected in the chromatograms [28].…”

The Phytochemistry of Cherokee Aromatic Medicinal Plants

“…Horseweed leaves used for toothache leaves [21] decoction of herb used to treat diarrhea herb [23] Mikasuki and Seminole Native Americans used the plant to treat sore throats and respiratory complaints [146] Whole plant: β-sitosterol, stigmasterol, β-sitosterol 3-O-β-D-glucoside, harmine, and sphingolipid [147] Aerial parts: triterpenoid erigeronol (showed potent anti-melanoma cytotoxicity) [149] Whole plant: conyzolide, conyzoflavone (both showed antimicrobial activities) [150] Whole plant: 8R,9R-dihydroxymatricarine methyl ester, matricarine methyl ester, matricarine lactone, Aerial parts: enyne derivatives, (2Z,8Z)-matricaria acid methyl ester, (4Z,8Z)-matricaria lactone, and (4Z)-lachnophyllum lactone [153] Aerial parts: (4Z)-lachnophyllum lactone, (4Z,8Z)-matricaria lactone, (2Z,8Z)-matricaria acid methyl ester; (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone showed antifungal activity against Aspergillus niger, Cladosporium sp., and Penicillium digitatum [154] Flowering parts: polyphenolic-polysaccharide (anticoagulant, antiplatelet activity) [155] Roots: dihydropyranones conyzapyranone A and B; 4Z,8Z-matricaria-γ-lactone, 4E,8Z-matricaria-γ-lactone, 9,12,13-trihydroxy-10(E)-octadecenoic acid, epifriedelanol, friedelin, taraxerol, simiarenol, spinasterol, stigmasterol, β-sitosterol, and apigenin; conyzapyranone B, 4E,8Z-matricaria-γ-lactone, and spinasterol showed cytotoxic activity [156,157] Roots: triterpenoid 3β-erythrodiol (inhibits MKN-45 gastric cell proliferation) [158] Roots: salicylic acid, methyl gallate [159] Roots: lanostane triterpenoids conyzagenin-A, conyzagenin-B [160] Coreopsis tinctoria Nutt. Asteraceae Tickseed root tea for diarrhea root [15] Plant: polyacetylenes, (2S)-(3Z,11E)-decadiene-5,7,9-triyne-1,2-diol and (2R)-(3E,11Z)-decadiene-5,7,9-triyne-1,2-diol [170] Plant: seven compounds made up the major contributions of antioxidant activity in C. tinctoria, including okanin, isookanin, marein, flavanomarein, 5,7,3 ,5 -tetrahydroxyflavanone-7-O-glucoside, 3,5-dicaffeoylquinic acid, and chlorogenic acid [171] Flowers: C 14 polyacetylene glycosides coreosides A-D [172] Buds: C 14 polyacetylene glycosides coreosides E and F [173] Flowers: C 14 polyacetylene glycosides coreosides A, B, D, and E [174] Flowers: chalcone marein, flavanone flavanomarein [175] Flowers Fruits: flavonoids (marein, flavanomarein, quercetagetin-7-O-glucoside, okanin aurone, leptosidin, luteolin, apigenin) and phenolic acids (chlorogenic acid, caffeic acid)…”