In Vitro and In Silico Pharmacological and Cosmeceutical Potential of Ten Essential Oils from Aromatic Medicinal Plants from the Mascarene Islands.

In this study, 10 essential oils (EOs), from nine plants (Cinnamomum camphora, Curcuma longa, Citrus aurantium, Morinda citrifolia, Petroselinum crispum, Plectranthus amboinicus, Pittosporum senacia, Syzygium coriaceum, and Syzygium samarangense) were assessed for their antimicrobial, antiaging and antiproliferative properties. While only S. coriaceum, P. amboinicus (MIC: 0.50 mg/mL) and M. citrifolia (MIC: 2 mg/mL) EOs showed activity against Cutibacterium acnes, all EOs except S. samarangense EO demonstrated activity against Mycobacterium smegmatis (MIC: 0.125-0.50 mg/mL). The EOs were either fungistatic or fungicidal against one or both tested Candida species with minimum inhibitory/fungicidal concentrations of 0.016-32 mg/mL. The EOs also inhibited one or both key enzymes involved in skin aging, elastase and collagenase (IC50: 89.22-459.2 µg/mL; 0.17-0.18 mg/mL, respectively). Turmerone, previously identified in the C. longa EO, showed the highest binding affinity with the enzymes (binding energy: -5.11 and -6.64 kcal/mol). Only C. aurantium leaf, C. longa, P. amboinicus, P. senacia, S. coriaceum, and S. samarangense EOs were cytotoxic to the human malignant melanoma cells, UCT-MEL1 (IC50: 88.91-277.25 µg/mL). All the EOs, except M. citrifolia EO, were also cytotoxic to the human keratinocytes non-tumorigenic cells, HaCat (IC50: 33.73-250.90 µg/mL). Altogether, some interesting therapeutic properties of the EOs of pharmacological/cosmeceutical interests were observed, which warrants further investigations.

Structural elucidation of an immunological arabinan from the rhizomes of Ligusticum chuanxiong, a traditional Chinese medicine.

In the present study, an immunological arabinan, LCP70-2A, was isolated from Ligusticum chuanxiong for the first time. The absolute molecular weight of LCP70-2A was determined to be 6.46 × 104 g/mol using the HPSEC-MALLS-RID method. The absolute configuration of arabinose in LCP70-2A was determined to be L-configuration. Physicochemical characterization revealed that LCP70-2A was a homogeneous polysaccharide and had a backbone of (1 â†’ 5)-linked α-L-Araf with terminal α-L-arabinose residues at position O-2 and O-3. Molecular conformation analysis showed that LCP70-2A was a branching polysaccharide with a compact coil chain conformation in 0.1 M NaCl solution. In addition, in vitro cell assays showed that LCP70-2A can activate macrophages by enhancing the phagocytosis and potentiating the secretion of immunoregulatory factors including NO, TNF-α, IL-6, and IL-1ß. Furthermore, LCP70-2A was proved to promote the production of ROS and NO using the zebrafish model, suggesting that LCP70-2A can be further developed as a candidate supplement for immunological enhancement.

In Vitro Human Metabolism and Inhibition Potency of Verbascoside for CYP Enzymes.

Verbascoside is found in many medicinal plant families such as Verbenaceae. Important biological activities have been ascribed to verbascoside. Investigated in this study is the potential of verbascoside as an adjuvant during tuberculosis treatment. The present study reports on the in vitro metabolism in human hepatic microsomes and cytosol incubations as well as the presence and quantity of verbascoside within Lippia scaberrima. Additionally, studied are the inhibitory properties on human hepatic CYP enzymes together with antioxidant and cytotoxic properties. The results yielded no metabolites in the hydrolysis or cytochrome P450 (CYP) oxidation incubations. However, five different methylated conjugates of verbascoside could be found in S-adenosylmethionine incubation, three different sulphate conjugates with 3'-phosphoadenosine 5'-phosphosulfate (PAPS) incubation with human liver samples, and very low levels of glucuronide metabolites after incubation with recombinant human uridine 5'-diphospho-glucuronosyltransferase (UGT) 1A7, UGT1A8, and UGT1A10. Additionally, verbascoside showed weak inhibitory potency against CYP1A2 and CYP1B1 with IC50 values of 83 µM and 86 µM, respectively. Potent antioxidant and low cytotoxic potential were observed. Based on these data, verbascoside does not possess any clinically relevant CYP-mediated interaction potential, but it has effective biological activity. Therefore, verbascoside could be considered as a lead compound for further drug development and as an adjuvant during tuberculosis treatment.