ABSTRACT
The LABEXTRACT plant extract bank, featuring diverse members of the Myrtaceae family from Brazilian hot spot regions, provides a promising avenue for bioprospection. Given the pivotal roles of the Spike protein and 3CLpro and PLpro proteases in SARS-CoV-2 infection, this study delves into the correlations between the Myrtaceae species from the Atlantic Forest and these targets, as well as an antiviral activity through both in vitro and in silico analyses. The results uncovered notable inhibitory effects, with Eugenia prasina and E. mosenii standing out, while E. mosenii proved to be multitarget, presenting inhibition values above 72% in the three targets analyzed. All extracts inhibited viral replication in Calu-3 cells (EC50 was lower than 8.3 µg·mL-1). Chemometric analyses, through LC-MS/MS, encompassing prediction models and molecular networking, identified potential active compounds, such as myrtucommulones, described in the literature for their antiviral activity. Docking analyses showed that one undescribed myrtucommulone (m/z 841 [M - H]-) had a higher fitness score when interacting with the targets of this study, including ACE2, Spike, PLpro and 3CLpro of SARS-CoV-2. Also, the study concludes that Myrtaceae extracts, particularly from E. mosenii and E. prasina, exhibit promising inhibitory effects against crucial stages in SARS-CoV-2 infection. Compounds like myrtucommulones emerge as potential anti-SARS-CoV-2 agents, warranting further exploration.
ABSTRACT
The objective of this study was to evaluate the effect of ChromatiNet on vegetative growth, total antioxidant capacity, phenolic and essential oils (EOs) composition of Lippia gracilis. The plants were cultivated under full sunlight, black, blue and red ChromatiNet. The flavonoid content and antioxidant capacity were quantified spectrophotometrically. The C-glycosylflavone isomers (orientin and isoorientin) were isolated and identified by conventional spectroscopic techniques and measured using high-performance liquid chromatography-diode array detection. The EO was analysed by gas chromatography and gas chromatography-mass spectrometry. Environment influenced growth, total antioxidant capacity and phytochemical levels. Shoot dry weight, thymol, carvacrol and (E)-caryophyllene were favoured under red and black ChromatiNet. Root growth, EOs, caryophyllene oxide, p-cymene, flavonoids, orientin and isoorientin were favoured in sunlight. Growth and accumulation of EOs, flavonoids and photosynthetic pigments increased under blue ChromatiNet. Therefore, Lippia gracilis plants have plasticity related to the spectral quality of light and it cultivate depends of the phytochemicals of interest.
ABSTRACT
Traditional medicine shows several treatment protocols for COVID-19 based on natural products, revealing its potential as a possible source of anti-SARS-CoV-2 agents. Ampelozizyphus amazonicus is popularly used in the Brazilian Amazon as a fortifier and tonic, and recently, it has been reported to relieve COVID-19 symptoms. This work aimed to investigate the antiviral potential of A. amazonicus, focusing on the inhibition of spike and ACE2 receptor interaction, a key step in successful infection. Although saponins are the major compounds of this plant and often reported as its active principles, a polyphenol-rich extract was the best inhibitor of the spike and ACE2 interaction. Chemical characterization of A. amazonicus bark extracts by LC-DAD-APCI-MS/MS before and after clean-up steps for polyphenol removal showed that the latter play an essential role in maintaining this activity. The effects of the extracts on viral replication were also assessed, and all samples (aqueous and ethanol extracts) demonstrated in vitro activity, inhibiting viral titers in the supernatant of Calu-3 cells after 24 hpi. By acting both in the SARS-CoV-2 cell entry process and its replication, A. amazonicus bark extracts stand out as a multitarget agent, highlighting the species as a promising candidate in the development of anti-SARS-CoV-2 drugs.
Subject(s)
COVID-19 , SARS-CoV-2 , Angiotensin-Converting Enzyme 2 , Plant Bark , Tandem Mass Spectrometry , Antiviral Agents/pharmacology , Protein BindingABSTRACT
Abstract The phenolic compound content, the antioxidant and α-amylase inhibition potentials of different extracts of the Plectranthus amboinicus, P. barbatus and P. ornatus were evaluated. We also evaluated the influence of plant growth and harvest time on the chemical composition of the essential oil (EO) of P. amboinicus, its antioxidant and anti-Candida activities and the α-amylase and lipoxygenase inhibitions. The turbo-extract of P. barbatus showed the greatest phenolic compound content and antioxidant activity. No α-amylase inhibition activity was observed in the analyzed extracts, but the turbo-extraction and refluxing extracts possessed high antioxidant activities. Protected cultivation and morning harvest conditions gave the best antioxidant activities, which was associated to the highest carvacrol content. P. amboinicus EO antioxidant activity could contribute to the reduction of oxidative stress in diabetes. Causal Candida strains of diabetic foot ulcers showed sensitivity to P. amboinicus EO. C. albicans and C. dubliniensis were the most sensitive of the selected Candida strains. Turbo-extracts or refluxing of the three species extracts and the EO of P. amboinicus should be considered as a potential candidate for the management the complications of type 2 diabetes.
