Phytochemical screening and antityrosinase activity of carvacrol, thymoquinone, and four essential oils of Lebanese plants

Multiplicative Effects of Essential Oils and Other Active Components on Skin Tissue and Skin Cancers

Naturally derived essential oils and their active components are known to possess various properties, ranging from anti-oxidant, anti-inflammatory, anti-bacterial, anti-fungal, and anti-cancer activities. Numerous types of essential oils and active components have been discovered, and their permissive roles have been addressed in various fields. In this comprehensive review, we focused on the roles of essential oils and active components in skin diseases and cancers as discovered over the past three decades. In particular, we opted to highlight the effectiveness of essential oils and their active components in developing strategies against various skin diseases and skin cancers and to describe the effects of the identified essential-oil-derived major components from physiological and pathological perspectives. Overall, this review provides a basis for the development of novel therapies for skin diseases and cancers, especially melanoma.

Exploring the multifaceted bioactivities of Lavandula pinnata L. essential oil: promising pharmacological activities

Introduction: This study investigates the biological activities of Lavandula pinnata essential oil (LPEO), an endemic lavender species from the Canary Islands, traditionally used in treating various ailments. Methods: LPEO was extracted by hydrodistillation and analyzed using GC-MS. Antioxidant activity was assessed by DPPH radical scavenging and total antioxidant capacity assays. Antimicrobial activity was evaluated by disc diffusion, MIC, MBC, and MFC determination against bacterial (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa) and fungal (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, Penicillium digitatum) strains. Antidiabetic and anti-gout potential were investigated through α-amylase, α-glucosidase, and xanthine oxidase inhibition assays. Antityrosinase activity was determined using a modified dopachrome method. Cytotoxicity was assessed by MTT assay against breast (MCF-7, MDA-MB-468), liver (HepG2), colon (HCT-15) cancer cells, and normal cells (PBMCs). Results and discussion: LPEO exhibits potent antiradical activity (IC50 = 148.33 ± 2.48 μg/mL) and significant antioxidant capacity (TAC = 171.56 ± 2.34 μg AA/mg of EO). It demonstrates notable antibacterial activity against four strains (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Pseudomonas aeruginosa) with inhibition zones ranging from 18.70 ± 0.30 mm to 29.20 ± 0.30 mm, along with relatively low MIC and MBC values. LPEO displays significant antifungal activity against four strains (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, and Penicillium digitatum) with a fungicidal effect at 1 mg/mL, surpassing the positive control (cycloheximide), and MIC and MFC values indicating a fungicidal effect. It exhibits substantial inhibition of xanthine oxidase enzyme (IC50 = 26.48 ± 0.90 μg/mL), comparable to allopurinol, and marked inhibitory effects on α-amylase (IC50 = 31.56 ± 0.46 μg/mL) and α-glucosidase (IC50 = 58.47 ± 2.35 μg/mL) enzymes.The enzyme tyrosinase is inhibited by LPEO (IC50 = 29.11 ± 0.08 mg/mL). LPEO displays moderate cytotoxic activity against breast, liver, and colon cancer cells, with low toxicity towards normal cells (PBMC). LPEO exhibits greater selectivity than cisplatin for breast (MCF-7) and colon (HCT-15) cancer cells but lower selectivity for liver (HepG2) and metastatic breast (MDA-MB-468) cancer cells. These findings suggest the potential of LPEO as an antioxidant, antimicrobial, anti-gout, antidiabetic, and anticancer agent.

Chemical Composition of Salvia fruticosa Mill. Essential Oil and Its Protective Effects on Both Photosynthetic Damage and Oxidative Stress in Conocephalum conicum L. Induced by Environmental Heavy Metal Concentrations

The genus Salvia L., belonging to the Lamiaceae family, contains more than 900 species distributed in various parts of the world. It is a genus containing aromatic plants used both in the culinary field and above all in the cosmetic area to produce several perfumes. Salvia fruticosa Mill., notoriously known as Greek Salvia, is a plant used since ancient times in traditional medicine, but today cultivated and used in various parts of Europe and Africa. Polar and apolar extracts of this plant confirmed the presence of several metabolites such as abietane and labdane diterpenoids, triterpenoids, steroids, and some flavonoids, causing interesting properties such as sedative, carminative, and antiseptic, while its essential oils (EOs) are mainly characterized by compounds such as 1,8-cineole and camphor. The aim of this work concerns the chemical analysis by GC and GC-MS, and the investigation of the biological properties, of the EO of S. fruticosa plants collected in eastern Sicily. The gas-chromatographic analysis confirmed the presence of 1,8-cineole (17.38%) and camphor (12.81%), but at the same time, also moderate amounts of α-terpineol (6.74%), β-myrcene (9.07%), camphene (8.66%), β-pinene (6.55%), and α-pinene (6.45%). To study the protective effect of EOs from S. fruticosa (both the total mixture and the individual compounds) on possible damage induced by heavy metals, an in vitro system was used in which a model organism, the liverwort Conocephalum conicum, was subjected to the effect of a mix of heavy metals (HM) prepared using values of concentrations actually measured in one of the most polluted watercourses of the Campania region, the Regi Lagni. Finally, the antioxidant response and the photosynthetic damage were examined. The exogenous application of the EO yields a resumption of the oxidative stress induced by HM, as demonstrated by the reduction in the Reactive Oxygen Species (ROS) content and by the increased activity of antioxidant enzyme catalase (CAT) and glutathione-S-transferase (GST). Furthermore, plants treated with HMs and EO showed a higher Fv/Fm (maximal quantum efficiency of PSII in the dark) with respect to HMs-only treated ones. These results clearly indicate the protective capacity of the EO of S. fruticosa against oxidative stress, which is achieved at least in part by modulating the redox state through the antioxidant pathway and on photosynthetic damage.

Evaluation of the antimicrobial effects of Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta: A review

The extensive use of antibiotics and vaccines against microbial infections can result in long-term negative effects on humans and the environment. However, there are a number of plants that have antimicrobial effects against various disease-causing microbes such as bacteria, viruses, and fungi without negative side effects or harm to the environment. In this regard, four particular plants- Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta have been widely considered due to their excellent antimicrobial effect and ample availability. In this review, we discuss their antimicrobial effects due to the presence of thymoquinone, p-cymene, pinene, alkaloids, limonene, camphene, and melanin. These antimicrobial compounds disrupt the cell membrane of microbes, inhibit cellular division, and form biofilm in bacterial species, eventually reducing the number of microbes. Extraction of these compounds from the respective plants is carried out by different methods such as soxhlet, hydro-distillation, liquid-liquid extraction (LLE), pressurized liquid extraction (PLE), solid-phase extraction (SPE), supercritical fluid extraction (SFE), pulsed electric field (PEF), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasound-assisted extraction (UAE), and high-voltage electrical discharge. Suitable selection of the extraction technique highly depends upon the associated advantages and disadvantages. In order to aid future study in this field, this review paper summarizes the advantages and disadvantages of each of these approaches. Additionally, the discussion covers how antimicrobial agents destroy harmful bacteria. Thus, this review offers in-depth knowledge to researchers on the antibacterial properties of Capsicum, Nigella sativa, Musa paradisiaca L. peels, and Citrus limetta.

Recent Advances in Herbal-Derived Products with Skin Anti-Aging Properties and Cosmetic Applications

Although aesthetic benefits are a desirable effect of the treatment of skin aging, it is also important in controlling several skin diseases, mainly in aged people. The development of new dermocosmetics has rapidly increased due to consumers' demand for non-invasive products with lower adverse effects than those currently available on the market. Natural compounds of plant origin and herbal-derived formulations have been popularized due to their various safe active products, which act through different mechanisms of action on several signaling pathways for skin aging. Based on this, the aim of the review was to identify the recent advances in herbal-derived product research, including herbal formulations and isolated compounds with skin anti-aging properties. The studies evaluated the biological effects of herbal-derived products in in vitro, ex vivo, and in vivo studies, highlighting the effects that were reported in clinical trials with available pharmacodynamics data that support their protective effects to treat, prevent, or control human skin aging. Thus, it was possible to identify that gallic and ferulic acids and herbal formulations containing Thymus vulgaris, Panax ginseng, Triticum aestivum, or Andrographis paniculata are the most promising natural products for the development of new dermocosmetics with skin anti-aging properties.

Origanum syriacum Phytochemistry and Pharmacological Properties: A Comprehensive Review

Herbal medicine has been gaining special interest as an alternative choice of treatment for several diseases, being generally accessible, cost-effective and safe, with fewer side-effects compared to chemically synthesized medicines. Over 25% of drugs worldwide are derived from plants, and surveys have shown that, when available, herbal medicine is the preferred choice of treatment. Origanum syriacum (Lamiaceae) is a widely used medicinal plant in the Middle East, both as a home and a folk remedy, and in the food and beverage industry. Origanum syriacum contains numerous phytochemical compounds, including flavonoids, phenols, essential oils, and many others. Because of its bioactive compounds, O. syriacum possesses antioxidant, antimicrobial, and antiparasitic capacities. In addition, it can be beneficial in the treatment of various diseases such as cancer, neurodegenerative disorders, and peptic ulcers. In this review, the chemical compositions of different types of extracts and essential oils from this herb will first be specified. Then, the pharmacological uses of these extracts and essential oils in various contexts and diseases will be discussed, putting emphasis on their efficacy and safety. Finally, the cellular and molecular mechanisms of O. syriacum phytochemicals in disease treatment will be described as a basis for further investigation into the plant’s pharmacological role.

Chemical Composition and Cosmeceutical Potential of the Essential Oil of Oncosiphon suffruticosum (L.) Källersjö

The South African medicinal plant Oncosiphon suffruticosum (L.) Källersjö is an important remedy used to treat chronic, respiratory, and skin ailments. From the essential oil (EO) extracted by the hydrodistillation, sixteen constituent components were identified with oxygenated monoterpenes: camphor (31.21%), filifolone (13.98%), chrysanthenone (8.72%), 1,8-cineole (7.85%), and terpinen-4-ol (7.39%) as predominant constituents. In the antibacterial activity study, the EO was found most susceptible against Pseudomonas aeruginosa with an MIC of 6.4 mg/mL; however, it showed the same activity against Staphylococcus aureus and Escherichia coli with an MIC value of 12.8 mg/mL. The sun protecting factor (SPF) of the EO was found to be 2.299 and thus establishing it as a potentially important cosmeceutical for sunscreen applications. This is the first report investigating the essential oil of O. suffruticosum for its chemical composition and skin-related in vitro biological activities viz antibacterial, antioxidant capacity, antityrosinase, and sun protection factor.

Essential Oils and Their Main Chemical Components: The Past 20 Years of Preclinical Studies in Melanoma

Simple Summary

In the last years, targeted therapy and immunotherapy modified the landscape for metastatic melanoma treatment. These therapeutic approaches led to an impressive improvement in patients overall survival. Unfortunately, the emergence of drug resistance and side effects occurring during therapy strongly limit the long-term efficacy of such treatments. Several preclinical studies demonstrate the efficacy of essential oils as antitumoral agents, and clinical trials support their use to reduce side effects emerging during therapy. In this review we have summarized studies describing the molecular mechanism through which essential oils induce in vitro and in vivo cell death in melanoma models. We also pointed to clinical trials investigating the use of essential oils in reducing the side effects experienced by cancer patients or those undergoing anticancer therapy. From this review emerged that further studies are necessary to validate the effectiveness of essential oils for the management of melanoma.

Abstract

The last two decades have seen the development of effective therapies, which have saved the lives of a large number of melanoma patients. However, therapeutic options are still limited for patients without BRAF mutations or in relapse from current treatments, and severe side effects often occur during therapy. Thus, additional insights to improve treatment efficacy with the aim to decrease the likelihood of chemoresistance, as well as reducing side effects of current therapies, are required. Natural products offer great opportunities for the discovery of antineoplastic drugs, and still represent a useful source of novel molecules. Among them, essential oils, representing the volatile fraction of aromatic plants, are always being actively investigated by several research groups and show promising biological activities for their use as complementary or alternative medicine for several diseases, including cancer. In this review, we focused on studies reporting the mechanism through which essential oils exert antitumor action in preclinical wild type or mutant BRAF melanoma models. We also discussed the latest use of essential oils in improving cancer patients’ quality of life. As evidenced by the many studies listed in this review, through their effect on apoptosis and tumor progression-associated properties, essential oils can therefore be considered as potential natural pharmaceutical resources for cancer management.

Antityrosinase Activity of Combretum micranthum, Euphorbia hirta and Anacardium occidentale Plants: Ultrasound Assisted Extraction Optimization and Profiling of Associated Predominant Metabolites

Tyrosinase is an important component of the enzyme polyphenol oxidase, which upon contact with the phenolic substrates forms the pigment melanin and induces undesirable food browning. The phenolic and triterpenoid compounds that naturally occur in plants are well known as tyrosinase inhibitors. Combretum micranthum (CM) leaves, Euphorbia hirta (EH) plant, and Anacardium occidentale (AO) fruits are traditionally known to have potential anti-tyrosinase activities. The aim of this study was to optimize the ultrasound-assisted extraction of secondary metabolites from these matrices, and to evaluate in tubo the antityrosinase activity of these extracts. Efforts were also taken to profile the secondary metabolites, mainly the phenolic and triterpenoid compounds, in order to understand their probable association with tyrosinase inhibition. The optimal ultrasound-assisted extraction conditions for simultaneous extraction of phenolic, and triterpenoid compounds were determined. The aqueous fraction of these extracts showed significant antityrosinase activity, with the CM leaves exhibiting the strongest inhibitory effect (IC50 of 0.58 g·L-1). The predominant metabolic compounds from these natural extracts were putatively identified by using a high-resolution quadrupole-time of flight (QToF) LC-MS instrument. The high-resolution accurate mass-based screening resulted in identification of 88 predominant metabolites, which included dihydrodaidzein-7-O-glucuronide, micromeric acid, syringic acid, morin, quercetin-3-O-(6″-malonyl-glucoside), 4-hydroxycoumarin, dihydrocaffeic acid-3-O-glucuronide, to name some, with less than 5 ppm of mass error.

Skin lightening effect of natural extracts coming from Senegal botanical biodiversity

BACKGROUND

Skin depigmentation is increasingly oriented toward plant extracts because of harmfulness of depigmenting active ingredients used in cosmetics and dermatology. Reconstructed human pigmented epidermis (RHPE) is the closest in vitro model to human skin and offers the possibility to test the global depigmenting effect of a plant extract. These co-cultures of keratinocytes and melanocytes are the most advanced and newest models for testing depigmentation, and until now very few studies have been done with these cultures. We investigated the cytotoxicity and the inhibitory effect on tyrosinase and melanogenesis of four extracts from Combretum micranthum (G. Don) leaves, Anacardium occidentale (L.) fruits, Moringa oleifera (Lam.) seeds, and Adansonia digitata (L.) seeds.

METHODS

The vegetal extracts were obtained by ultrasound-assisted extraction and the vegetal oils by maceration. Anti-tyrosinase properties of two aqueous extracts were evaluated. Then, the cytotoxicity and depigmenting effects of these plant extracts were tested in vitro with RHPE model delivered by SkinEthic^® .

RESULTS

Antityrosinase activities were found to be 84.58% and 31.02% for C. micranthum and A. occidentale, respectively. All extracts, except A. occidentale, showed to be nontoxic. C. micranthum, M. oleifera, A. digitata, and mixture of M. oleifera and A. digitata extracts have shown, for the first time, an in vitro depigmenting activity equivalent or even more important than kojic acid.

CONCLUSIONS

These natural extracts coming from Senegal botanical biodiversity could be used in cosmetic and dermatology as alternative agents to achieve skin depigmentation. Further study should be focused on the mechanism of action of these plant extracts.