Phenolic Compounds from the Aerial Parts of Blepharis linariifolia Pers. and Their Free Radical Scavenging and Enzyme Inhibitory Activities

Comprehensive In Vitro Evaluation of Antibacterial, Antioxidant, and Computational Insights into Blepharis ciliaris (L.) B. L. Burtt from Hail Mountains, Saudi Arabia

The arid mountainous region of Hail in Saudi Arabia has a variety of desert vegetation, some of which are conventionally used in Bedouin traditional medicine. These plants need scientific examination. This research seeks to examine Blepharis ciliaris using a thorough multi-analytical methodology that includes antibacterial and antioxidant assessments as well as computational modeling. GC-MS analysis of the methanolic extract revealed 17 organic compounds, including pentadecanoic acid, ethyl methyl ester (2.63%); hexadecanoic acid, methyl ester (1.00%); 9,12-octadecadienoic acid (Z,Z)-, methyl ester (2.74%); 9-octadecenoic acid, methyl ester (E) (2.78%); octadecanoic acid (5.88%); 9-tetradecenoic acid (Z) (3.22%); and undec-10-enoic acid, undec-2-n-1-yl ester (5.67%). The DPPH test evaluated antioxidant activity, revealing a notable increase with higher concentrations of the methanolic extract, achieving maximum inhibition of 81.54% at 1000 µg/mL. The methanolic extract exhibited moderate antibacterial activity, with average inhibition zones of 10.33 ± 1.53 mm, 13.33 ± 1.53 mm, 10.67 ± 1.53 mm, and 10.00 ± 2.00 mm against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Serratia marcescens, respectively, as determined by the disk diffusion method. The minimum inhibitory concentration (MIC) values were 500 µg/mL for S. aureus and B. subtilis, whereas E. coli and S. marcescens showed susceptibility at 1000 µg/mL. Computational simulations were employed to assess the toxicity, drug-likeness, and ADMET profiles of compounds derived from Blepharis ciliaris. Thirteen bioactive compounds were assessed in silico against Staphylococcus aureus sortase A (PDB: 1T2O), Bacillus subtilis BsFabHb (PDB: 8VDB), Escherichia coli LPS assembly protein (LptD) (PDB: 4RHB), and a modeled Serratia marcescens outer-membrane protein TolC, focusing on cell wall and membrane structures. Compound 3, (+)-Ascorbic acid 2,6-dihexadecanoate, shown significant binding affinities to B. subtilis BsFabHb, E. coli LPS assembly protein, and S. marcescens TolC.

Xanthine oxidase inhibition study of isolated secondary metabolites from Dolichandrone spathacea (Bignoniaceae): In vitro and in silico approach

Xanthine oxidase (XO) has been widely recognized as a pivotal enzyme in developing hyperuricemia, primarily contributing to the excessive production of uric acid during purine metabolism in the liver. One of the standard treatment approaches involves reducing uric acid levels by inhibiting XO activity. In this study, the leaf extract of Dolichandrone spathacea, traditionally used in folk medicine, was found to inhibit XO activity in the ethyl acetate and butanol fractions at a concentration of 100 µg/mL, their values were 78.57 ± 3.85 % (IC50 = 55.93 ± 5.73 µg/ml) and 69.43 ± 8.68 % (IC50 = 70.17 ± 7.98 µg/ml), respectively. The potential XO inhibitory components were isolated by bioactivity assays and the HR-ESI-MS and NMR spectra system. The main constituents of leaf extracts of Dolichandrone spathacea, six compounds, namely trans-4-methoxycinnamic acid (3), trans-3,4-dimethoxycinnamic acid (4), p-coumaric acid (5), martynoside (6), 6-O-(p-methoxy-E-cinnamoyl)-ajugol (7), and scolymoside (17), were identified as potent XO inhibitors with IC50 values ranging from 19.34 ± 1.63 μM to 64.50 ± 0.94 μM. The enzyme kinetics indicated that compounds 3-5, 7, and 17 displayed competitive inhibition like allopurinol, while compound 6 displayed a mixed-type inhibition. Computational studies corroborated these experimental results, highlighting the interactions between potential metabolites and XO enzyme. The hydrogen bonds played crucial roles in the binding interaction, especially, scolymoside (17) forms a hydrogen bond with Mos3004, exhibited the lowest binding energy (-18.3286 kcal/mol) corresponding to the lowest IC50 (19.34 ± 1.63 μM). Furthermore, nine compounds were isolated for the first time from this plant. In conclusion, Dolichandrone spathacea and its constituents possess the potential to modulate the xanthine oxidase enzyme involved in metabolism.

Plant Extracts as Skin Care and Therapeutic Agents

Natural ingredients have been used for centuries for skin treatment and care. Interest in the health effects of plants has recently increased due to their safety and applicability in the formulation of pharmaceuticals and cosmetics. Long-known plant materials as well as newly discovered ones are increasingly being used in natural products of plant origin. This review highlights the beneficial effects of plants and plant constituents on the skin, including moisturizing (e.g., Cannabis sativa, Hydrangea serrata, Pradosia mutisii and Carthamus tinctorius), anti-aging (e.g., Aegopodium podagraria, Euphorbia characias, Premna odorata and Warburgia salutaris), antimicrobial (e.g., Betula pendula and Epilobium angustifolium), antioxidant (e.g., Kadsura coccinea, Rosmarinus officinalis, Rubus idaeus and Spatholobus suberectus), anti-inflammatory (e.g., Antidesma thwaitesianum, Helianthus annuus, Oenanthe javanica, Penthorum chinense, Ranunculus bulumei and Zanthoxylum bungeanum), regenerative (e.g., Aloe vera, Angelica polymorpha, Digitaria ciliaris, Glycyrrihza glabra and Marantodes pumilum), wound healing (e.g., Agrimonia eupatoria, Astragalus floccosus, Bursera morelensis, Jatropha neopauciflora and Sapindus mukorossi), photoprotective (e.g., Astragalus gombiformis, Calea fruticose, Euphorbia characias and Posoqueria latifolia) and anti-tyrosinase activity (e.g., Aerva lanata, Bruguiera gymnorhiza, Dodonaea viscosa, Lonicera japonica and Schisandra chinensis), as well as their role as excipients in cosmetics (coloring (e.g., Beta vulgaris, Centaurea cyanus, Hibiscus sabdariffa and Rubia tinctiorum), protective and aromatic agents (e.g., Hyssopus officinalis, Melaleuca alternifolia, Pelargonium graveolens and Verbena officinalis)).

Methodologies for Assessing Pancreatic Lipase Catalytic Activity: A Review

Obesity is a disease of epidemic proportions with a concerning increasing trend. Regarded as one of the main sources of energy, lipids can also represent a big part of an unnecessary intake of calories and be, therefore, directly related to the problem of obesity. Pancreatic lipase is an enzyme that is essential in the absorption and digestion of dietary fats and has been explored as an alternative for the reduction of fat absorption and consequent weigh loss. Literature describes a great variability of methodologies and experimental conditions used in research to evaluate the in vitro inhibitory activity of compounds against pancreatic lipase. However, in an attempt to choose the best approach, it is necessary to know all the reaction conditions and understand how these can affect the enzymatic assay. The objective of this review is to understand and summarize the methodologies and respective experimental conditions that are mainly used to evaluate pancreatic lipase catalytic activity. 156 studies were included in this work and a detailed description of the most commonly used UV/Vis spectrophotometric and fluorimetric instrumental techniques are presented, including a discussion regarding the differences found in the parameters used in both techniques, namely enzyme, substrate, buffer solutions, kinetics conditions, temperature and pH. This works shows that both UV/Vis spectrophotometry and fluorimetry are useful instrumental techniques for the evaluation of pancreatic lipase catalytic activity, presenting several advantages and limitations, which make the choice of parameters and experimental conditions a crucial decision to obtain the most reliable results.

Ultrasound-Assisted Extraction of Verbascoside from Clerodendrum glandulosum Leaves for Analysis of Antioxidant and Antidiabetic Activities

Verbascoside (VER) is a phenylethanoid glycoside compound found in Clerodendrum species and is an important part of traditional medicine. It is found in the leaves of Clerodendrum glandulosum, which is taken as a soup or vegetable and also utilized in traditional medicine by the people of Northeast India, especially against hypertension and diabetes. In the present study, VER was extracted from C. glandulosum leaves using ultrasound-assisted extraction through the solvent extraction method (ethanol-water, ethanol, and water). The ethanol extract had the highest phenolic and flavonoid contents, viz., 110.55 mg GAE/g and 87.60 mg QE/g, respectively. HPLC and LC-MS were used to identify the active phenolic compound, and VER was found to be the main component present in the extraction with a molecular weight of 624.59 g/mol. NMR (¹H, 2D-COSY) analysis showed the presence of hydroxytyrosol, caffeic acid, glucose, and rhamnose in the VER backbone. Further, different antioxidant activities and antidiabetic and antihyperlipidemia enzyme markers' inhibition against VER-enriched ethanol extract were evaluated. The results showed that ultrasound extraction of polyphenols using ethanol from C. glandulosum could be a promising technique for the extraction of bioactive compounds.

Antibacterial activity of β-sitosterol isolated from the leaves of Odontonema strictum (Acanthaceae)

The observation of a dog eating the roots of Odontonema strictum in 2008 in Lubumbashi (DR. Congo) was the starting point of this research which later led to the isolation of β-sitosterol (BSL), a known phytosterol, isolated for the first time from the leaves of this tropical plant which has a large range of medicinal properties including anti-inflammation, anti-hypertension and antibacterial. The analysis of the ¹H NMR spectrum showed that the active compound contains 60% of BSL and 40% of stigmasterol. With a melting point (m.p.) of 134-136 °C and the R_f value 0.55 in EtOAc-hexane (1:3) on silica gel TLC, the active compound was confirmed to be BSL. Here, we determined the minimal inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of BSL on Staphylococcus aureus by the broth dilution method. The MIC and MBC were found to be 1.24 mg/mL and 2.208 mg/mL, respectively. For the crude extract, the MIC and MBC were 4.33 mg/mL and the MBC was 7.66 mg/mL, respectively. The Total antibacterial activity underlined the fact that the crude extract from 1 g of plant materials could be diluted 65 times and still retains the ability to inhibit the growth of S. aureus. This is the first report of the antibacterial activity of BSL from this plant.