Anti-quorum sensing activity of some medicinal plants

Background: Quorum sensing is the key regulator of virulence factors of Pseudomonas aeruginosa such as biofilm formation, motility, productions of proteases, hemolysin, pyocyanin, and toxins. The aim of this study was to explore the effect of the extracts from some medicinal plants on quorum sensing and related virulence factors of P. aeruginosa.Material and Methods: Quorum sensing inhibitory (OSI) effect of the alcohol extracts of 20 medicinal plants was evaluated by Chromobacterium violaceum reporter using agar cup diffusion method. The efficient QSI extracts were tested for their activity against biofilm synthesis, motility, and synthesis of pyocyanin from P. aeruginosa PA14Results: The extracts of Citrus sinensis, Laurus nobilis, Elettaria cardamomum, Allium cepa, and Coriandrum sativum exhibited potent quorum quenching effect. On the other hand, Psidium guajava and Mentha longifolia extracts showed lower QSI activity. These extracts exhibited significant elimination of pyocyanin formation and biofilm development of Pseudomonas aeruginosa PA14. In addition, they significantly inhibited twitching and swimming motilities of P. aeruginosa PA14.Conclusion: This study illustrated, for the first time, the importance of C. sinensis, L. nobilis, E. cardamomum, A. cepa, and C. sativum as quorum sensing inhibitors and virulence suppressors of P. aeruginosa. Thus, these plants could provide a natural source for the elimination of Pseudomonas pathogenesis.Keywords: Quorum sensing inhibitory activity, P. aeruginosa, Chromobacterium violaceum, virulence factor

A REVIEW OF TRADITIONAL USES, PHYTOCHEMICALS AND BIOACTIVITIES OF THE GENUS HYPOESTES

Background: Plants have been used as a folkloric source of medicinal agents since the beginning of mankind. The genus Hypoestes (family Acanthaceae) includes over 150 species. The ethno-pharmacological studies of the plant belonging to this genus indicated that they possess various bioactivities as cytotoxic, anti-leismanial, antimicrobial, antimalarial, antioxidant, and anti-trypanosomal. Furthermore, they have been utilized in different traditional medicines for treating various aliments as eye sores, breast, liver, heart, and skin diseases, respiratory infections, anemia, malaria, scabies, typhoid, hypertension, and gonorrhea. This review focuses on the traditional uses, chemical constituents, and bioactivities of Hypoestes species. Methods: The information was acquired from a literature searching in electronic databases such as ScienceDirect, PubMed, Google-Scholar, SpringerLink, Scopus, and Wiley up to 2017 for publications on genus Hypoestes. Results: The genus Hypoestes had varied classes of chemical constituents, including diterpenoids, alkaloids, lignans, and pentacyclic triterpenes. Herein, 46 metabolites and more than 30 references have been cited. Conclusion: This works provides a background for the future studies on Hypoestes species, particularly the species, which have not been extensively explored for separation and characterization of bioactive constituents and pharmacological potentials

Chemical constituents and biological investigations of the aerial parts of Egyptian Clerodendrum inerme

B-friedoolean-5-ene-3-β-ol (1), β-sitosterol (2), stigmasta-5,22,25-trien-3-β-ol (3), betulinic acid (4), and 5-hydroxy-6,7,4′-trimethoxyflavone (5) were isolated from the aerial parts of Clerodendrum inerme L. (Verbenaceae). Their structures were established based on analyses of physical and spectroscopic data. Compounds 1, 4, and 5 were isolated for the first time from the plant. C. inerme L. was known as a rich source of terpenes, sterols, and phenolic compounds, so the antioxidant and anti-inflammatory activities were evaluated. The total methanolic extract (TME) and compound 5 showed scavenging activity with maximum inhibition of 61.84% for TME (100 μg/mL) and 37.19% for 5 (20 μM), respectively, using DPPH assay. In addition, the TME exhibited anti-inflammatory activity more than indomethacin at dose 200 mg/kg using the formalin induced hind paw edema method

<i>Ginkgo biloba</i> leaves extract’s cosmeceutical evaluation: a preliminary assessment of human volunteers toward achieving improved skin conditions and rejuvenation

Ginkgo biloba (GB) leaves extract is known to possess potent antioxidants and other bioactivities such as improved skin conditions and rejuvenation. This study aimed to develop a cosmeceutical preparation to utilize the strong antioxidant potential of GB leaves as part of the skincare formulation. Cream incorporated GB (GBC) was prepared by mixing the obtained extract with stearic acid-sodium hydroxide components in an emulsion format. The obtained GBC was characterized for GB contents, uniformity, pH, compatibility, stability, and skin’s human application. A homogeneous, physically, and chemically stable, with pH near the skin pH and shiny cream, was obtained. The prepared cream was easy to rub and pearly in appearance. It was effective and safe during the two-week trial conducted on human volunteers according to clinical trial registry protocols. The cream scavenged free radicals in DPPH assay tests. The cream incorporated GB made the skin more spirited and tauter. Furthermore, the wrinkles were reduced and the skin was renewed vigor. The GBC worked at the topical level and provided benefits when applied daily for the trial duration. The formulation also provided visually observable anti-wrinkle effects on the skin, with visible improvements in the skin’s shape and texture. The prepared cream can be used to rejuvenate the skin.</p

A Comprehensive In Silico Study of New Metabolites from Heteroxenia fuscescens with SARS-CoV-2 Inhibitory Activity

Chemical investigation of the total extract of the Egyptian soft coral Heteroxenia fuscescens, led to the isolation of eight compounds, including two new metabolites, sesquiterpene fusceterpene A (1) and a sterol fuscesterol A (4), along with six known compounds. The structures of 1&ndash;8 were elucidated via intensive studies of their 1D, 2D-NMR, and HR-MS analyses, as well as a comparison of their spectral data with those mentioned in the literature. Subsequent comprehensive in-silico-based investigations against almost all viral proteins, including those of the new variants, e.g., Omicron, revealed the most probable target for these isolated compounds, which was found to be Mpro. Additionally, the dynamic modes of interaction of the putatively active compounds were highlighted, depending on 50-ns-long MDS. In conclusion, the structural information provided in the current investigation highlights the antiviral potential of H. fuscescens metabolites with 3&beta;,5&alpha;,6&beta;-trihydroxy steroids with different nuclei against SARS-CoV-2, including newly widespread variants