Evaluation of the antimicrobial activity of Acalypha monostachya Cav. (Euphorbiales: Euphorbiaceae)

Abstract

Acalypha monostachya (Euphorbiaceae) is used by the inhabitants of San Rafael and ZapotitlanSalinas, Puebla, Mexico, to alleviate illnesses of bacterial and fungal origin. We analyzed the antimicrobial activity of A. monostachya and some of its chemical features. The extracts were obtained by percolation. The antibacterial and antifungal activities were examined through the disc-diffusion method. The general toxicity was carried out by using Artemia salina. The quenching of free radicals by extracts was evaluated by the decolouration of a methanol solution of DPPH·. Total phenols were determined by Folin Ciocalteu reagent. Gram-positive and negative bacteria were sensitive to methanol and hexane extracts. The methanol extract had a bactericidal effect on Vibrio cholera Tor (MIC = 1000 µg/mL). The fungi strain most sensitive to this extract was T. mentagrophytes (LC 50 = 430 µg/mL). The methanol extract showed inhibition of DPPH· radical (SC 50 = 3.45 µg/ml), 43.4% of total phenolics and was toxic against A. salina (LC 50 = 4.5 µg/mL). The methanol extract showed a variety of phenolic compounds, while hexane extract showed different fatty acids methyl ester. The bacterial, antifungal, antioxidant activities and a qualitative chemical characterization of A. monostachya's extracts are reported here for the first time.

Sensitisation to fungi in atopic dermatitis patients over 14 years of age and the relation to the occurrence of food hypersensitivity reactions

“…55,[58][59][60][61][62][63][64][65] Another study demonstrated that antifungal potency may be due to the abundance of linoleic and α-linolenic acids in the major fraction of fatty acids methyl esters. [66][67][68] In our previous study we confirmed the significant relation between the severity of AD and the occurrence of food hypersensitivity reactions to sea fishes; the reactions to sea fishes are recorded in 8% of patients suffering from mild form of AD, in 8% of patients suffering from moderate form of AD and in 28% of patients suffering from severe form of AD. 29,30 Another reason for the significant direct relation between the sensitisation to fungi and the occurrence of food hypersensitivity reactions to nuts and fishes may be the fact that positive SPT reactions to fungi are mostly observed in patients with multiple sensitivity to various allergens.…”

Phytochemical analysis, antimicrobial and radical-scavenging properties of Acalypha manniana leaves

“…The findings of the present study explain why the plant extracts are used in traditional folk medicine and confirm the activity of A. manniana as a broad spectrum antimicrobial agent since it inhibited the growth of Gram-positive ( S. aureus , E. faecalis ) and gram negative bacteria ( E. coli , P. aeruginosa , K. pneumoniae, P. mirabilis , S. paratyphi A , S. paratyphi B , S. flexneri) as well as some fungi ( T. mentagrophytes , T. terrestre , T. equinum , M. gypseum ). Similar findings had been reported for other species by Canales et al (2011) and Haruna et al (2013). The antimicrobial activities of A. manniana (MIC = 0.25 - 2.04 mg/mL) can also be considered very important compared with those of Haruna et al (2013) who reported the antimicrobial activities of the leaves of A. wilkesiana methanolic extract and its four derivative fractions (MIC = 25–100 mg/mL) on human pathogenic bacteria namely S. aureus , S. pyogenes , E. faecalis , P. aeruginosa , P. vulgaris , E. coli, Aspergillus niger , A. flavus , A. carbonerium , T. mentagrophytes and Candida albicans .…”

“…These compounds varied within the fractions. In agreement with our results, the phytochemical screening of the leaf extracts of Acalypha hispida, A. marginata, A. racemosa, A. monostachya, A. alnifolia , A. wilkesiana and A. indica revealed the presence of phenolics, tannins, steroids, flavonoids, glycosides, saponins and anthraquinones that varied within the plant species (Iniaghe et al 2009; Gotep et al 2010; Canales et al 2011; Evanjelene & Natarajan 2012; Mohan et al 2012). …”

“…The ethanolic extract of A. wilkesiana leaves revealed the presence of tannins, steroids, flavonoids and cardiac glycosides while saponins, alkaloids and anthraquinones were not present (Gotep et al 2010). A variety of phenolic compounds and fatty acids methyl ester were found in the A. monostachya extracts (Canales et al 2011). The antifungal properties of extracts of leaves of A. hispida have been established (Ejechi & Souzey 1999).…”

“…Gallic acid, corilagin and geraniin have been reported to be the active compounds responsible for the antimicrobial activity of A. wilkesiana while quercetin 3-O-rutinoside and kaempferol 3-O-rutinoside were also isolated from the inactive fraction of A. hispida (Adesina et al 2000). The antibacterial, antifungal and/or antioxidant activities of A. monostachya , A. wilkesiana, A. indica, A.alnifolia , A. hispida were also mentioned (Alade & Irobi 1993; Canales et al 2011; Shirwaikar et al 2004; Govindarajan et al 2008; Durga et al 2009; Onocha et al 2011; Evanjelene & Natarajan 2012; Haruna et al 2013). However, no systematic work has been undertaken on analyzing the extracts of A. manniana.…”