(1) Background: Viral respiratory infections cause life-threatening diseases in millions of people worldwide every year. Human coronavirus and several picornaviruses are responsible for worldwide epidemic outbreaks, thus representing a heavy burden to their hosts. In the absence of specific treatments for human viral infections, natural products offer an alternative in terms of innovative drug therapies. (2) Methods: We analyzed the antiviral properties of the leaves and stem bark of the mulberry tree (Morus spp.). We compared the antiviral activity of Morus spp. on enveloped and nonenveloped viral pathogens, such as human coronavirus (HCoV 229E) and different members of the Picornaviridae family—human poliovirus 1, human parechovirus 1 and 3, and human echovirus 11. The antiviral activity of 12 water and water–alcohol plant extracts of the leaves and stem bark of three different species of mulberry—Morus alba var. alba, Morus alba var. rosa, and Morus rubra—were evaluated. We also evaluated the antiviral activities of kuwanon G against HCoV-229E. (3) Results: Our results showed that several extracts reduced the viral titer and cytopathogenic effects (CPE). Leaves’ water-alcohol extracts exhibited maximum antiviral activity on human coronavirus, while stem bark and leaves’ water and water-alcohol extracts were the most effective on picornaviruses. (4) Conclusions: The analysis of the antiviral activities of Morus spp. offer promising applications in antiviral strategies.
Numerous studies have led to a better understanding of the mechanisms of action of viruses in systemic infections for the development of prevention strategies and very promising antiviral therapies. Viruses still remain one of the main causes of human diseases, mainly because the development of new vaccines is usually challenging and drug resistance has become an increasing concern in recent decades. Therefore, the development of potential antiviral agents remains crucial and is an unmet clinical need. One abundant source of potential therapeutic molecules are plants: they biosynthesize a myriad of compounds, including peptides which can have antimicrobial activity. Our objective is to summarize the literature on peptides with antiviral properties derived from plants and to identify key features of these peptides and their application in systemic viral infections. This literature review highlights studies including clinical trials which demonstrated that plant cyclotides have the ability to inhibit the growth of viruses causing human diseases, defensin-like peptides possess anti-HIV-1 activity, and lipid transfer proteins and some lectins exhibit a varied antimicrobial profile. To conclude, plant peptides remain interesting to explore in the context of emerging and re-emerging infectious diseases.
The common cold is generally considered a usually harmless infectious disease of the upper respiratory pathway, with mostly mild symptoms. However, it should not be overlooked, as a severe cold can lead to serious complications, resulting in hospitalization or death in vulnerable patients. The treatment of the common cold remains purely symptomatic. Analgesics as well as oral antihistamines or decongestants may be advised to relieve fever, and local treatments can clear the airways and relieve nasal congestion, rhinorrhea, or sneezing. Certain medicinal plant specialties can be used as therapy or as complementary self-treatment. Recent scientific advances discussed in more detail in this review have demonstrated the plant’s efficiency in the treatment of the common cold. This review presents an overview of plants used worldwide in the treatment of cold diseases.
Trace metal contamination is a widespread and complex environmental problem. Because fungi are capable of growing in adverse environments, several fungal species could have an interesting potential in remediation technologies for metal contaminated environments. This study proposes to test the ability to tolerate and biosorb three trace metals (Cd, Cu and Pb) of 28 fungal isolates collected from different soils. First, a tolerance assay in agar medium was performed. Each isolate was grown in the presence of Cd, Cu, and Pb at different concentrations. Then, we exposed each soil fungus to 50 mg L-1 of Cd, Cu, or Pb during 3 days in liquid medium. Parameters such as biomass production, pH, and biosorption were evaluated. The results showed that responses to metal exposure are very diverse even with fungi isolated from the same soil sample, or belonging to the same genera. Several isolates could be considered as good metal biosorbents and could be used in future mycoremediation studies. Among the 28 fungi tested, Absidia cylindrospora biosorbed more than 45% of Cd and Pb, Chaetomium atrobrunneum biosorbed more than 45% of Cd, Cu, Pb, and Coprinellus micaceus biosorbed 100% of Pb.
The wastewater from hospitals, pharmaceutical industries and more generally human and animal dejections leads to environmental releases of antibiotics that cause severe problems for all living organisms. The aim of this study was to investigate the capacity of three fungal strains to biotransform the fluoroquinolone levofloxacin. The degradation processes were analyzed in solid and liquid media. Among the three fungal strains tested, Coriolopsis gallica strain CLBE55 (BRFM 3473) showed the highest removal efficiency, with a 15% decrease in antibiogram zone of inhibition for Escherichia coli cultured in solid medium and 25% degradation of the antibiotic in liquid medium based on high-performance liquid chromatography (HPLC). Proteomic analysis suggested that laccases and dye-decolorizing peroxidases such as extracellular enzymes could be involved in levofloxacin degradation, with a putative major role for laccases. Degradation products were proposed based on mass spectrometry analysis, and annotation suggested that the main product of biotransformation of levofloxacin by Coriolopsis gallica is an N-oxidized derivative.