Deverra triradiata Hochst. ex Boiss. from the Northern Region of Saudi Arabia: Essential Oil Profiling, Plant Extracts and Biological Activities.

Devrra triradiata Hochst. ex Boiss is an occasional plant species in the Northern region of Saudi Arabia. The shrub is favored on sandy desert wadis, gypsaceous substrate, and sandy gravel desert. In folk medicine, the plant is used for many purposes; to relieve stomach pains, against intestinal parasites, and for the regulation of menstruation. The present study describes the chemical composition of the essential oils (EOs) of different plant parts of D. triradiata. In vivo and in vitro biological activities of plant extracts and essential oils were also studied. Phenylpropanoids, elemicin (flowers: 100%), dillapiole (Stems: 82.33%; and seeds: 82.61%), and apiol (roots: 72.16%) were identified as the major compounds. The highest antioxidant activity was recorded for the EOs of roots and stems (IC50 = 0.282 µg/mL and 0.706 µg/mL, respectively). For plant extracts, ethyl acetate showed the highest antioxidant activities (IC50 = 2.47 and 3.18 µg/mL). EOs showed high antifungal activity against yeasts with low azole susceptibilities (i.e., Malassezia spp. and Candida krusei). The MIC values of EOs ranged between 3.4 mg/mL and 56.4 mg/mL. The obtained results also showed phytotoxic potential of plant extracts both on the germination features of Triticum aestivum seeds and the vegetative growth of seedlings.

Conventional therapy and new antifungal drugs against Malassezia infections.

Malassezia yeasts are commensal microorganisms occurring on the skin of humans and animals causing dermatological disorders or systemic infections in severely immunocompromised hosts. Despite attempts to control such yeast infections with topical and systemic antifungals, recurrence of clinical signs of skin infections as well as treatment failure in preventing or treating Malassezia furfur fungemia have been reported most likely due to wrong management of these infections (e.g., due to early termination of treatment) or due to the occurrence of resistant phenomena. Standardized methods for in vitro antifungal susceptibility tests of these yeasts are still lacking, thus resulting in variable susceptibility profiles to azoles among Malassezia spp. and a lack of clinical breakpoints. The inherent limitations to the current pharmacological treatments for Malassezia infections both in humans and animals, stimulated the interest of the scientific community to discover new, effective antifungal drugs or substances to treat these infections. In this review, data about the in vivo and in vitro antifungal activity of the most commonly employed drugs (i.e., azoles, polyenes, allylamines, and echinocandins) against Malassezia yeasts, with a focus on human bloodstream infections, are summarized and their clinical implications are discussed. In addition, the usefulness of alternative compounds is discussed.

Dittrichia viscosa L. Ethanolic Extract Based Ointment with Antiradical, Antioxidant, and Healing Wound Activities.

Dittrichia viscosa which belongs to the Asteraceae family is frequently used to treat hematomas and skin disorders in Mediterranean herbal medicine. This study aims to validate its antioxidant effects and its potential on healing wounds. The ethanolic extract of D. viscosa leaves was formulated as 2.5% and 5% (w/w) in ointment bases on the beeswax and sesame oil. During this study, the ethanolic D. viscosa extract, ointments containing 2.5% and 5% of D. viscosa extract, and the vehiculum were assessed for their total phenol content (TPC), caffeoylquinic acid content (CQC), and antioxidant activities using complementary methods (TAC, the DPPH, ABTS, FRAP, and the BCB). The effects on wound healing of obtained ointments were evaluated by excision of the wound in a mice model for 12 days. Subsequently, the excised wound areas were measured at the 3rd, 9th, and 12th days. The skin tissues were isolated for histological studies. The ointments containing D. viscosa extract (2.5%, 5%) possessed a considerable TPC, CQC, radical scavenging potential, and antioxidant activities compared to the vehiculum. Treated animals with ointments containing D. viscosa extract at 2.5% and 5% showed almost and totally healed wounds compared to the vehiculum and control groups, evidenced by good skin regeneration and reepithelialization. The present work showed the role of D. viscosa antioxidants exerted by its polyphenolic compounds, in particular, caffeoylquinic acids, in enhancing wound healing.

Chemical characterization and acaricidal activity of Drimia maritima (L) bulbs and Dittrichia viscosa leaves against Dermanyssus gallinae.

The emergence of resistance to chemical acaricides in Dermanyssus gallinae, together with their toxicity and high costs, has prompted investigations into the use of plant extracts as alternatives to chemical acaricidal treatments. Drimia maritima bulbs and Dittrichia viscosa (D. viscosa) leaf extracts were here characterized by HPLC-PDA-ESI-MS/MS, and their toxicity against D. gallinae was evaluated using contact methods. Twenty-nine compounds were identified in D. maritima extracts, with glucoscilliphaeoside derivatives (i.e., quercetin, kaempferol and bufadienolides) as the major components. Twenty-four phenolic compounds, mainly caffeic acid derivatives, were detected in D. viscosa extracts. D. maritima extracts displayed a significantly higher (p < 0.05) acaricidal activity than D. viscosa extracts, with 100% of D. gallinae mortality at a concentration of 100 mg/mL following 24 h exposure. The mortality rate of D. gallinae induced by D. viscosa extracts ranged from 25 to 45% following 48 h exposure at a concentration of 200 mg/mL. The acetonic extract of D. viscosa and D. maritima displayed the highest efficacy against D. gallinae. This study provides evidence of the diversity of bioactive compounds present in D. maritima bulbs and D. viscosa leaf extracts, which are both efficacious against D. gallinae. The higher efficacy of D. maritima bulb extracts might be linked to the presence of bufadienolides in its extracts.

Chemical Composition, Antibacterial and Antifungal Activities of Crude Dittrichia viscosa (L.) Greuter Leaf Extracts.

The small amount of data regarding the antifungal activity of Dittrichia viscosa (L.) Greuter against dermatophytes, Malassezia spp. and Aspergillus spp., associated with the few comparative studies on the antimicrobial activity of methanolic, ethanolic, and butanolic extracts underpins the study herein presented. The total condensed tannin (TCT), phenol (TPC), flavonoid (TFC), and caffeoylquinic acid (CQC) content of methanol, butanol, and ethanol (80% and 100%) extracts of D. viscosa were assessed and their bactericidal and fungicidal activities were evaluated. The antibacterial, anti-Candida and anti-Malassezia activities were evaluated by using the disk diffusion method, whereas the anti-Microsporum canis and anti-Aspergillus fumigatus activities were assessed by studying the toxicity effect of the extracts on vegetative growth, sporulation and germination. The methanolic extract contained the highest TPC and CQC content. It contains several phytochemicals mainly caffeoylquinic acid derivatives as determined by liquid chromatography with photodiode array and electrospray ionisation mass spectrometric detection (LC/PDA/ESI-MS) analysis. All extracts showed an excellent inhibitory effect against bacteria and Candida spp., whereas methanolic extract exhibited the highest antifungal activities against Malassezia spp., M. canis and A. fumigatus strains. The results clearly showed that all extracts, in particular the methanolic extract, might be excellent antimicrobial drugs for treating infections that are life threatening (i.e., Malassezia) or infections that require mandatory treatments (i.e., M. canis or A. fumigatus).