Phytochemical and Nutraceutical Screening of Ethanol and Ethyl Acetate Phases of Romanian Galium verum Herba (Rubiaceae)

Galium species are used worldwide for their antioxidant, antibacterial, antifungal, and antiparasitic properties. Although this plant has demonstrated its antitumor properties on various types of cancer, its biological activity on cutaneous melanoma has not been established so far. Therefore, the present study was designed to investigate the phytochemical profile of two extracts of G. verum L. herba (ethanolic and ethyl acetate) as well as the biological profile (antioxidant, antimicrobial, and antitumor effects) on human skin cancer. The extracts showed similar FT-IR phenolic profiles (high chlorogenic acid, isoquercitrin, quercitrin, and rutin), with high antioxidant capacity (EC50 of ethyl acetate phase (0.074 ± 0.01 mg/mL) > ethanol phase (0.136 ± 0.03 mg/mL)). Both extracts showed antimicrobial activity, especially against Gram-positive Streptococcus pyogenes and Staphylococcus aureus bacilli strains, the ethyl acetate phase being more active. Regarding the in vitro antitumor test, the results revealed a dose-dependent cytotoxic effect against A375 melanoma cell lines, more pronounced in the case of the ethyl acetate phase. In addition, the ethyl acetate phase stimulated the proliferation of human keratinocytes (HaCaT), while this effect was not evident in the case of the ethanolic phase at 24 h post-stimulation. Consequently, G. verum l. could be considered a promising phytocompound for the antitumor approach of cutaneous melanoma.

Accumulation Capacity of Nickel and Zinc in Yerba Mate Cultivated in Soils with Contrasting Parent Materials

Yerba mate (Ilex paraguariensis St. Hill.) has shown a relatively high capacity for micronutrient absorption and could be a candidate for biofortification and combating a lack of micronutrients. To further evaluate the accumulation capacity of Ni and Zn, yerba mate clonal seedlings were grown in containers under five rates of Ni or Zn (0, 0.5, 2, 10, and 40 mg kg-1) with three soils originating from different parent material (basalt, rhyodacite, and sandstone). After 10 months, plants were harvested, divided into component parts (leaves, branches, and roots), and evaluated for 12 elements. The use of Zn and Ni enhanced seedling growth under rhyodacite- and sandstone-derived soils at the first application rate. Application of Zn and Ni resulted in linear increases based on Mehlich I extractions; recovery of Ni was smaller than Zn. Root Ni concentration increased from approximately 20 to 1000 mg kg-1 in rhyodacite-derived soil and from 20 to 400 mg kg-1 in basalt- and sandstone-derived soils; respective increases in leaf tissue were ~ 3 to 15 mg kg-1 and 3 to 10 mg kg-1. For Zn, the maximum obtained values were close to 2000, 1000, and 800 mg kg-1 for roots, leaves, and branches for rhyodacite-derived soils, respectively. Corresponding values for basalt- and sandstone-derived soils were 500, 400, and 300 mg kg-1, respectively. Although yerba mate is not a hyperaccumulator, this species has a relatively high capacity to accumulate Ni and Zn in young tissue with the highest accumulation occurring in roots. Yerba mate showed high potential to be used in biofortification programs for Zn.

New insights of the application of water or ethanol-water plant extract rich in active compounds in food

Plants are recognized as natural sources of antioxidants (e.g., polyphenols, flavonoids, vitamins, and other active compounds) that can be extracted by green solvents like water, ethanol, or their binary mixtures. Plant extracts are becoming more used as food additives in various food systems due to their antioxidant abilities. Their application in food increases the shelf life of products by preventing undesirable changes in nutritional and sensory properties, such as the formation off-flavors in lipid-rich food. This review summarizes the most recent literature about water or ethanol-water plant extracts used as flavors, colorings, and preservatives to fortify food and beverages. This study is performed with particular attention to describing the benefits of plant extract-fortified products such as meat, vegetable oils, biscuits, pastries, some beverages, yogurt, cheese, and other dairy products. Antioxidant-rich plant extracts can positively affect food safety by partially or fully replacing synthetic antioxidants, which have lately been linked to safety and health issues such as toxicological and carcinogenic consequences. On the other hand, the limitations and challenges of using the extract in food should be considered, like stability, level of purity, compatibility with matrix, price, sensory aspects like distinct taste, and others. In the future, continuous development and a tendency to use these natural extracts as food ingredients are expected, as indicated by the number of published works in this area, particularly in the past decade.

Oligochitosan fortifies antioxidative and photosynthetic metabolism and enhances secondary metabolite accumulation in arsenic-stressed peppermint

The current study was designed to investigate whether application of irradiated chitosan (ICn), a recently established plant growth promoter, can prove effective in alleviating arsenic (As) stress in peppermint, a medicinally important plant. This study investigated how foliar application of ICn alleviated As toxicity in peppermint (Mentha piperita L.). Peppermint plants were treated with ICn (80 mg L^-1) alone or in combination with As (10, 20, or 40 mg kg^-1 of soil, as Na₂HAsO₄·7H₂O) 40 days after transplantation (DAT), and effects on the growth, photosynthesis, and antioxidants were assessed at 150 DAT as stress severely decreases plant growth, affects photosynthesis, and alters enzymatic (ascorbate peroxidase, superoxide dismutase) and non-enzymatic (glutathione) antioxidants. When applied at 40 mg kg^-1, ICn significantly decreased the content of essential oil (EO) and total phenols in peppermint by 13.8 and 16.0%, respectively, and decreased phenylalanine ammonia lyase (PAL) and deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) activities by 12.8 and 14.6%, respectively. Application of ICn mitigated the disadvantageous effects caused by As toxicity in peppermint by enhancing activities of antioxidative enzymes and photosynthesis and increased accretion of secondary metabolism products (EOs and phenols). An enhancement of total phenols (increased by 17.3%) and EOs (36.4%) is endorsed to ICn-stimulated enhancement in the activities of PAL and DXR (65.9 and 28.9%, respectively) in comparison to the control. To conclude, this study demonstrated that foliar application of ICn (80 mgL^-1) effectively promoted the growth and physiology of peppermint and eliminated As-induced toxicity to achieve high production of EO-containing crops grown in metal-contaminated soils.

Innovative Green Chemistry Approach to Synthesis of Sn2+-Metal Complex and Design of Polymer Composites with Small Optical Band Gaps

In this work, the green method was used to synthesize Sn²⁺-metal complex by polyphenols (PPHs) of black tea (BT). The formation of Sn²⁺-PPHs metal complex was confirmed through UV-Vis and FTIR methods. The FTIR method shows that BT contains NH and OH functional groups, conjugated double bonds, and PPHs which are important to create the Sn²⁺-metal complexes. The synthesized Sn²⁺-PPHs metal complex was used successfully to decrease the optical energy band gap of PVA polymer. XRD method showed that the amorphous phase increased with increasing the metal complexes. The FTIR and XRD analysis show the complex formation between Sn²⁺-PPHs metal complex and PVA polymer. The enhancement in the optical properties of PVA was evidenced via UV-visible spectroscopy method. When Sn²⁺-PPHs metal complex was loaded to PVA, the refractive index and dielectric constant were improved. In addition, the absorption edge was also decreased to lower photon. The optical energy band gap decreases from 6.4 to 1.8 eV for PVAloaded with 30% (v/v) Sn²⁺-PPHs metal complex. The variations of dielectric constant versus wavelength of photon are examined to measure localized charge density (N/m*) and high frequency dielectric constant. By increasing Sn²⁺-PPHs metal complex, the N/m* are improved from 3.65 × 10⁵⁵ to 13.38 × 10⁵⁵ m⁻³ Kg⁻¹. The oscillator dispersion energy (E_d) and average oscillator energy (E_o) are measured. The electronic transition natures in composite films are determined based on the Tauc’s method, whereas close examinations of the dielectric loss parameter are also held to measure the energy band gap.

Antimicrobial activity, in vitro anticancer effect (MCF-7 breast cancer cell line), antiangiogenic and immunomodulatory potentials of Populus nigra L. buds extract

PURPOSE

The aim of this study was to evaluate the antioxidant potential, antimicrobial activity, the in vitro anticancer effect (tested on MCF-7 breast cancer cell line), as well as the antiangiogenic and immunomodulatory potential of Populus nigra L. bud (Pg) extract collected from the western part of Romania.

RESULTS

Populus nigra L. bud extract presents an important antioxidant activity, due to the rich phytochemical composition. Regarding the biological activity, results have shown that poplar bud extract presents a significant inhibitory activity against Gram-positive bacteria and a dose-dependent decrease of MCF-7 tumor cell viability with an IC₅₀ of 66.26 μg/mL, while not affecting healthy cells. Phenomena of early apoptotic events at the maximum concentration tested (150 μg/mL) were detected by Annexin V-PI double staining. The extract induced G0/G1 phase cell cycle arrest. In addition, Pg extract showed antiangiogenic potential on the chorioallantoic membrane. Also, at the highest concentration (150 μg/mL), good tolerability and no signs of toxicity upon vascular plexus were observed. Moreover, in low concentrations, the Pg extract had immunomodulatory activity on primary human dendritic cells by upregulating IL-12 and IL-23 subunits.

CONCLUSION

The study concludes that poplar bud extract elicited antioxidant activity, antitumor properties on the breast cancer cell line, followed by an antiangiogenic effect and an immunomodulatory potential on human primary dendritic cells. The biological activity of Populus nigra L. buds extract may open new directions of research on the topic addressed.

Impact of a Graphene Oxide Reducing Agent on a Semi-Permeable Graphene/Reduced Graphene Oxide Forward Osmosis Membrane Filtration Efficiency

Graphene has been considered as a material that may overcome the limitations of polymer semi-permeable membranes in water treatment technology. However, monolayer graphene still suffers from defects that cause leakage. Here, we report a method of sealing defects in graphene transferred onto porous polymer substrate via reduced graphene oxide (rGO). The influence of various reducing agents (e.g., vitamin C, hydrazine) on the properties of rGO was investigated by SEM, Raman, FTIR, and XRD. Subsequently, membranes based on graphene/reduced graphene oxide were tested in a forward osmosis system using sodium chloride (NaCl). The effect of the effectiveness of the reduction of graphene oxide, the type and number of attached groups, the change in the distance between the rGO flakes, and the structure of this material were examined in terms of filtration efficiency. As a result, semi-permeable centimetre-scale membranes with ion blocking efficiency of up to 90% and water flux of 20 mL h⁻¹ m⁻² bar⁻¹ were proposed.

Melissa officinalis L. Aqueous Extract Exerts Antioxidant and Antiangiogenic Effects and Improves Physiological Skin Parameters

Melissa officinalis (MO) is a medicinal plant well-known for its multiple pharmacological effects, including anti-inflammatory, anticancer and beneficial effects on skin recovery. In this context, the present study was aimed to investigate the in vitro and in vivo safety profile of an MO aqueous extract by assessing cell viability on normal (HaCaT-human keratinocytes) and tumor (A375-human melanoma) cells and its impact on physiological skin parameters by a non-invasive method. In addition, the antioxidant activity and the antiangiogenic potential of the extract were verified. A selective cytotoxic effect was noted in A375 cells, while no toxicity was noticed in healthy cells. The MO aqueous extract safety profile after topical application was investigated on SKH-1 mice, and an enhanced skin hydration and decreased erythema and transepidermal water loss levels were observed. The in ovo CAM assay, performed to investigate the potential modulating effect on the angiogenesis process and the blood vessels impact, indicated that at concentrations of 100 and 500 µg/mL, MO aqueous extract induced a reduction of thin capillaries. No signs of vascular toxicity were recorded at concentrations as high as 1000 μg/mL. The aqueous extract of MO leaves can be considered a promising candidate for skin disorders with impaired physiological skin parameters.

Sugarcane Bagasse as a Co-Substrate with Oil-Refinery Biological Sludge for Biogas Production Using Batch Mesophilic Anaerobic Co-Digestion Technology: Effect of Carbon/Nitrogen Ratio

Man-made organic waste leads to the rapid proliferation of pollution around the globe. Effective bio-waste management can help to reduce the adverse effects of organic waste while contributing to the circular economy at the same time. The toxic oily-biological sludge generated from oil refineries’ wastewater treatment plants is a potential source for biogas energy recovery via anaerobic digestion. However, the oily-biological sludge’s carbon/nitrogen (C/N) ratio is lower than the ideal 20–30 ratio required by anaerobic digestion technology for biogas production. Sugarcane bagasse can be digested as a high C/N co-substrate while the oily-biological sludge acts as a substrate and inoculum to improve biogas production. In this study, the best C/N with co-substrate volatile solids (VS)/inoculum VS ratios for the co-digestion process of mixtures were determined empirically through batch experiments at temperatures of 35–37 °C, pH (6–8) and 60 rpm mixing. The raw materials were pre-treated mechanically and thermo-chemically to further enhance the digestibility. The best condition for the sugarcane bagasse delignification process was 1% (w/v) sodium hydroxide, 1:10 solid-liquid ratio, at 100 °C, and 150 rpm for 1 h. The results from a 33-day batch anaerobic digestion experiment indicate that the production of biogas and methane yield were concurrent with the increasing C/N and co-substrate VS/inoculum VS ratios. The total biogas yields from C/N 20.0 with co-substrate VS/inoculum VS 0.06 and C/N 30.0 with co-substrate VS/inoculum VS 0.18 ratios were 2777.0 and 9268.0 mL, respectively, including a methane yield of 980.0 and 3009.3 mL, respectively. The biogas and methane yield from C/N 30.0 were higher than the biogas and methane yields from C/N 20.0 by 70.04 and 67.44%, respectively. The highest biogas and methane yields corresponded with the highest C/N with co-substrate VS/inoculum VS ratios (30.0 and 0.18), being 200.6 mL/g VSremoved and 65.1 mL CH4/g VSremoved, respectively.

Estimation of the Content of Selected Active Substances in Primary and Secondary Herbal Brews by UV-VIS and GC-MS Spectroscopic Analyses

Primary and secondary herbal brews were tested for the content of polyphenolic compounds, flavonoids, and essential oil. The brewing process was carried out at an initial temperature of 95°C and different time parameters (5, 10, 15, and 30 min). A secondary brewing was also carried out to estimate the reuse of the herbal material. The highest content of polyphenol compounds and flavonoids was determined in the primary peppermint brews (4017 mg L^-1 and 360 mg L^-1, respectively). The secondary brews were characterised by a lower content of active substances than the primary brews. The study showed that the herbal postbrewing material contained significant levels of essential oil (from 13.04% to 95.65%) and may be an alternative source of volatile bioactive compounds.

Herbal Medicine Characterization Perspectives Using Advanced FTIR Sample Techniques - Diffuse Reflectance (DRIFT) and Photoacoustic Spectroscopy (PAS)

This study demonstrates the significant potential of the Fourier transform infrared spectroscopy (FTIR) sampling methods: cantilever-enhanced Fourier transform infrared photoacoustic spectroscopy (FTIR PAS) and diffuse reflectance infrared spectroscopy (FTIR DRIFT) in the field of herbal medicines (HM). In the present work we investigated DRIFT and PAS sampling methods because they do not require sample preparation, samples may be opaque or dark, require small amounts, both liquid and solid samples can be measured, and solid samples can be analyzed on a small scale. Experiments conducted prove high sensitivity, reproducibility and capability in combination with an unsupervised multivariate analysis technique to discriminate important characteristics of HM, such as the identification of plant parts, differentiation of samples by types, and determination of the concentration of extractable compounds in HM.

Romanian Wormwood (Artemisia absinthium L.): Physicochemical and Nutraceutical Screening

Artemisia species are used worldwide for their antioxidant, antimicrobial and anti-inflammatory properties. This research was designed to investigate the phytochemical profile of two ethanolic extracts obtained from leaves and stems of A. absinthium L. as well as the biological potential (antioxidant activity, cytotoxic, anti-migratory and anti-inflammatory properties). Both plant materials showed quite similar thermogravimetric, FT-IR phenolic profile (high chlorogenic acid) with mild antioxidant capacity [ascorbic acid (0.02–0.1) > leaves (0.1–2.0) > stem (0.1–2.0)]. Alcoholic extracts from these plant materials showed a cytotoxic effect against A375 (melanoma) and MCF7 (breast adenocarcinoma) and affected less the non-malignant HaCaT cells (human keratinocytes) at 72 h post-stimulation and this same trend was observed in the anti-migratory (A375, MCF7 > HaCat) assay. Lastly, extracts ameliorated the pro-inflammatory effect of TPA (12-O-tetradecanoylphorbol-13-acetate) in mice ears, characterized by a diffuse neutrophil distribution with no exocytosis or micro-abscesses.

Elemental Characterization of Romanian Crop Medicinal Plants by Neutron Activation Analysis

The metallic elements concentrations of medicinal plants (coriander, dill, Echinacea, lavender, chamomile, mint, and plantain, used for phytopharmaceutical products), cultivated in unpolluted region, were analyzed by neutron activation analysis. The essential nutrients, macro-, micro-, and trace elements (K, Ca, Mg, Na, Fe, Mn, Rb, Sr, and Zn), potentially toxic elements (Al, As, Ba, Co, Sb, Cr, and V), and rare earth elements were monitored and were compared with those presented in the literature. An estimation of their contributions to intake and toxicity for a person was made, which revealed that (a) teas prepared from the examined plants represent useful contribution to the food provided intake of three essential macronutrients (K, Ca, and Mg); (b) the Cu, Mn, Rb, Sr, Zn, and rare earths levels are normal or low; (c) the quantities of As, Ba, Co, Sb, Cr, and V do not represent toxicological concerns; (d) the examination of the estimated Al and Fe quantities recovered in infusions in the conditions of usual daily tea consumption is below the Tolerable Daily Intake values. The strategy of cultivation of medicinal plants in unpolluted areas is efficient and beneficial. However, individual plants ability to concentrate preferentially certain elements suggests controlling the contamination level of raw materials.