Screening of selected medicinal plants for in vitro antidermatophytic activity

In vitro antidermatophytic activity of bioactive compounds from selected medicinal plants

Fungal infections are among the most difficult diseases to manage in humans. Eukaryotic fungal pathogens share many similarities with their host cells, which impairs the development of antifungal compounds. Therefore, it is desirable to harness the pharmaceutical potential of medicinal plants for antifungal drug discovery. In this study, the antifungal activity of sixteen plant extracts was investigated against selected dermatophytic fungi. Of the sixteen plants, the cladode (leaf) of Asparagus racemosus, and seed extract of Cassia occidentalis showed antifungal activity against Microsporum gypseum, Microsporum nanum, Trichophyton mentagrophytes and Trichophyton terrestre. The plant antifungal compounds were located by direct bioassay against Cladosporium herbarum. IR and NMR spectrometry analyses of these compounds identified the presence of saponin (in A. racemosus) and hydroxy anthraquinone (in C. occidentalis) in these antifungal compounds. The antidermatophytic activity of plant anthraquinone and saponins with reports of little or no hemolytic activity, makes these compounds ideal for alternative antifungal therapy and warrants further in-depth investigation in vivo.

Investigation of Wound Healing and Anti-Inflammatory Activities of Solvent Fractions of 80% Methanol Leaf Extract of Achyranthes aspera L. (Amaranthaceae) in Rats

INTRODUCTION

The various fractions of leaves of Achyranthes aspera L. (A. aspera) have not yet been explored scientifically for in-vivo wound healing and anti-inflammatory activities. The objective of this study was, therefore, to evaluate in-vivo wound healing and anti-inflammatory activities of solvent fractions of 80% methanol leaf extract of A. aspera in rats.

METHODS

The 80% methanol leaf extract of A. aspera was fractionated with chloroform, n-butanol and water. Wound healing and anti-inflammatory activities were evaluated using excision and incision wound models, rat paw edema and cotton pellet-induced granuloma models, respectively. For wound healing activity, fractions were evaluated at 5 and 10% ointments. The positive control groups were treated with nitrofurazone 0.2% ointment. Simple ointment treated for excision wound model and untreated for incision wound model rats were assigned as negative controls. For anti-inflammatory activity, fractions were evaluated at 100, 200 and 400mg/kg. Positive control groups were treated with indomethacin 10mg/kg for both rat paw edema and cotton pellet-induced granuloma models. The 2% Tween 80 treated rats were assigned as negative controls for both anti-inflammatory activity models. All groups comprised of 6 rats and treatment administrations were made topically and orally for evaluation of wound healing and anti-inflammatory activities.

RESULTS

The 10% w/w chloroform fraction ointment revealed a high percentage of wound contraction and reduced period of epithelialization (p <0.01). Chloroform fraction was also found to be the most active fraction, which demonstrated the maximum percentage inhibition of edema (52.50%; p <0.01) and transudative and proliferative component of chronic inflammation (37.52 and 52.81%; p <0.01), which was comparable to indomethacin.

CONCLUSION

Data obtained from this study collectively indicated that a chloroform fraction of 80% methanol leaf extract of A. aspera possessed significant wound healing and anti-inflammatory activities.

Mo-CBP4, a purified chitin-binding protein from Moringa oleifera seeds, is a potent antidermatophytic protein: In vitro mechanisms of action, in vivo effect against infection, and clinical application as a hydrogel for skin infection

Dermatophytes belonging to Trichophyton ssp. are important anthropophilic and zoophilic pathogens, which developed resistance to griseofulvin, the common antifungal drug used to treat dermatophytosis. In this context, Moringa oleifera seed proteins have been described as antifungal agents with potential applications. Thus, this work aimed to evaluate the antidermatophytic in vitro, focusing on mechanisms, and in vivo potential of Mo-CBP₄, purified from M. oleifera seeds. Mo-CBP₄was purified after protein extraction with 50 mM Tris-HCl buffer, pH 8.0, and chromatography on chitin and CM Sepharose™ columns and antidermatophytic potential of Mo-CBP₄ evaluated in vitro and in vivo. In vitro, Mo-CBP₄ reduced in 50% the germination of microconidia of Trichophyton mentagrophytes at 45 μM; but did not show inhibition of mycelial growth. Mo-CBP₄ (45 μM) presents the inhibitory activity even when incubated with N-acetyl-d-glucosamine (NAG). Analysis of the mechanisms of Mo-CBP₄ revealed an increase in membrane permeability, ROS overproduction and damage to cell wall leading to microconidia death. Furthermore, using in vivo models, Mo-CBP₄ (5, 10 and 20 mg g^-1) reduced the severity and time of dermatophytosis. Altogether, these findings indicate that Mo-CBP₄ has great potential for the development of novel antifungal drugs for the clinical treatment of dermatophytosis.