Seasonal Changes in Essential Oil Constituents of Cystoseira compressa: First Report

In Vitro and In Silico Antioxidant Activity and Molecular Characterization of Bauhinia ungulata L. Essential Oil

Bauhinia ungulata is an antioxidant medicinal plant that has been manipuled in Brazil to lower glycemic index as well is for alternative treatment for diabetes. Therefore, the present hearch has aimed to investigates the antioxidant effects of the essential oil of Bauhinia ungulata L. (EOBU) collected in Amazon region better specified in Boa Vista, Roraima, Brazil, located in the Amazon region. Gas chromatography had been used to characterize the components, and antioxidant assays such as DPPH, TAC, reducing power, Fe2+ chelation, and total phenols had also been performed. The major constituents had molecularly anchored with the human catalase (CAT) enzyme, and maltol has showed as a positive control. Among the 25 revealed components, the main ones have been α-bisabolol (27.2 %), β-Caryophyllene (12.5 %) and Epi-γ-eudesmol (13.6 %). The EOBU has comproved a TAC value of 618.79 mg of ascorbic acid equivalent, free radical scavenging capacity (DPPH) around 53.7 % and 65.27 %, Fe2+ chelation capacity of 161±6 and 126.7±39.6, for 0.1 mg.mL-1 and 0.5 mg.mL-1 , respectively. The power around the EOBU has appeared percentages equals to 28.66 %, 44.6 %, and 77.03 % in the concentrations tested. As well as, 96.5 % of total phenols. The compounds α-bisabolol (-5.7±0.4 Kcal.mol-1 ) and β-caryophyllene (-6.1±0.5 Kcal.mol-1 ) have showed good interaction with CAT compared to Maltol (-4.4±0.4 Kcal.mol-1 ). The present work has demonstrated that EOBU functions as a potent antioxidant, capable of scavenging free radicals and reducing oxidative stress damage.

Heliotropium ramosissimum metabolic profiling, in silico and in vitro evaluation with potent selective cytotoxicity against colorectal carcinoma

Heliotropium is a genus of the Boraginaceae family. Its members are used in many traditional and folklore medicines to treat several ailments. Despite this widespread usage, only a few evidence-based scientific studies investigated and identified its phytoconstituents. Herein, we documented the chemical profile of the Heliotropium ramosissimum methanolic extract using gas chromatography-mass spectrometry (GC–MS) and liquid chromatography-tandem mass spectrometry (LC–ESI–MS/MS) and assessed its antioxidant and cytotoxic effects. The methanolic extract exhibited high phenolic content (179.74 ± 0.58 µg/mL) and high flavonoid content (53.18 ± 0.60 µg/mL). The GC–MS analysis of the lipoidal matter allowed us to identify 41 compounds with high percentages of 1,2-benzenedicarboxylic acid, bis(2-methoxyethyl) ester (23.91%), and 6,10,14-trimethylpentadecan-2-one (18.74%). Thirty-two phytomolecules were tentatively identified from the methanolic extract of H. ramosissimum using LC–MS/MS. These compounds belonged to several phytochemical classes such as phenolic acids, alkaloids, coumarins, and flavonoids. Furthermore, we assessed the antioxidant activity of the methanolic extract by DPPH assay and oxygen radical absorbance capacity assay, which yielded IC₅₀ values of 414.30 µg/mL and 170.03 ± 44.40 µM TE/equivalent, respectively. We also assessed the cytotoxicity of the methanolic extract on seven different cell lines; Colo-205, A-375, HeLa, HepG-2, H-460, and OEC showed that it selectively killed cancer cells with particularly potent cytotoxicity against Colo-205 without affecting normal cells. Further studies revealed that the extract induced apoptosis and/or necrosis on Colo-205 cell line at an IC₅₀ of 18.60 µg/mL. Finally, we conducted molecular docking on the LC–ESI–MS/MS-identified compounds against colon cancer antigen 10 to find potentially cytotoxic compounds. Binding score energy analysis showed that isochlorogenic acid and orientin had the highest affinity for the colon cancer antigen 10 protein, with binding scores of (− 13.2001) and (− 13.5655) kcal/mol, respectively. These findings suggest that Heliotropium ramosissimum contains potent therapeutic candidates for colorectal cancer treatment.

Effects of Rubus fruticosus and Juniperus oxycedrus derivatives on culturability and viability of Listeria monocytogenes

The consumers' demand for safe foods without chemical additives increased the research for green solutions, based on natural antimicrobials. Plants can be an important source of bioactive compounds able to prevent the development of foodborne pathogens and spoilage microflora. This paper aimed to characterize phenolic extracts (PEs) and essential oils (EOs) obtained from Mediterranean Rubus fruticosus leaves and Juniperus oxycedrus needles and to evaluate their antimicrobial effects against Listeria monocytogenes Scott A. The growth dynamics with sub-lethal concentrations of plant derivatives were modeled and flow cytometry was used to better evidence the effect on cell viability and culturability. The results showed that these plant derivatives affected the growth of L. monocytogenes, increasing lag phase (about 40 h in the presence of PEs vs. 8 h in the control) and decreasing the final cell load of at least 1 log cycle with respect to the control. R. fruticosus EO was the most effective, determining an initial decrease of cell counts of about 6 log cycles, followed by a restart of growth after 10 h, with rate similar to the control (0.08 with R. fruticosus EO vs. 0.09 ((log CFU/ml)/h in the control) but significantly lower final cell load (7.33 vs. 8.92 log CFU/ml). According to flow cytometry, only R. fruticosus EO induced a relevant increase of dead cells, while the other plant derivatives determined different extent of sub-lethal cell injury. The discrepancy observed in some cases between viability and culturability could indicate the presence of cells not able to grow in culture media, whose fate needs to be further investigated to assess their potential recovery, thus bringing to an overestimation of the antimicrobial effect of these substances. This research contributed to increase the knowledge of these underused raw materials such as blackberry leaves and juniper needles that can be exploited in food and other industries.

Variations in the Composition, Antioxidant and Antimicrobial Activities of Cystoseira compressa during Seasonal Growth

The underexplored biodiversity of seaweeds has recently drawn great attention from researchers to find the bioactive compounds that might contribute to the growth of the blue economy. In this study, we aimed to explore the effect of seasonal growth (from May to September) on the in vitro antioxidant (FRAP, DPPH, and ORAC) and antimicrobial effects (MIC and MBC) of Cystoseira compressa collected in the Central Adriatic Sea. Algal compounds were analyzed by UPLC-PDA-ESI-QTOF, and TPC and TTC were determined. Fatty acids, among which oleic acid, palmitoleic acid, and palmitic acid were the dominant compounds in samples. The highest TPC, TTC and FRAP were obtained for June extract, 83.4 ± 4.0 mg GAE/g, 8.8 ± 0.8 mg CE/g and 2.7 ± 0.1 mM TE, respectively. The highest ORAC value of 72.1 ± 1.2 µM TE was obtained for the August samples, and all samples showed extremely high free radical scavenging activity and DPPH inhibition (>80%). The MIC and MBC results showed the best antibacterial activity for the June, July and August samples, when sea temperature was the highest, against Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The results show C. compressa as a potential species for the industrial production of nutraceuticals or functional food ingredients.