Bridging the Chemical Profile and Biological Activities of a New Variety of Agastache foeniculum (Pursh) Kuntze Extracts and Essential Oil.

This study investigated the phytochemical content of alcoholic extracts and essential oil of a new variety of medicinal plants, Agastache foeniculum (Pursh), which Kuntze adapted for cultivation in Romania, namely "Aromat de Buzau". The essential oil was investigated by GC-MS, while the identification and quantification of various compounds from alcoholic extracts were performed by HPLC-DAD. The total phenol and flavonoid contents of the extracts were evaluated by using standard phytochemical methods. The antioxidant activities of ethanol, methanol extracts, and essential oil of the plant were also assessed against 2,2'-diphenyl-1-picrylhydrazyl (DPPH•), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and by ferric reducing power (FRAP) using spectroscopic methods. Cyclic voltammetry was used to evaluate the antioxidant capacity of the essential oil. The concentrations of phenolic compounds were higher in methanolic extract compared to ethanolic extract. A significant correlation was found between total phenol and total flavonoid contents (r = 0.9087). Significant high correlations were also found between the total phenolic compounds and the antioxidant activities of the extracts (r ≥ 0.8600, p < 0.05). In addition, the extracts and essential oil showed good antioxidant and xanthine oxidase inhibitory activities. Estragole was detected as the major constituent of the essential oil (94.89%). The cytotoxic activity of the essential oil was evaluated by the MTT assay. At lower concentrations (1 µg/mL) high cytotoxicity against MCF-7 breast cancer cells was observed but not on the non-tumoral dermal fibroblasts (HDF) which indicated selectivity for cancer cells and suggests the presence of biologically active components that contribute to the observed high cytotoxic effect. Findings from the present study offer new perspectives on the use of A. foeniculum as a potential source of bioactive compounds and a good candidate for pharmaceutical plant-based products.

Flavonoid Profiles of Two New Approved Romanian Ocimum Hybrids.

Basil (Ocimum spp.) is a traditional herbal medicine abundant in antioxidants such as phenolic compounds. As part of a diet, this herb is proved to have some roles in decreasing the risk of cancer, and in the treatment of inflammation and neurodegenerative diseases. This study aims to explore the total phenolic and flavonoid content of two new basil hybrids growing in Romania, namely "Aromat de Buzau" (AB) and "Macedon" (MB). The antioxidant capacity of those two species was also analyzed by DPPH and cyclic voltammetry. Six different flavonoids, such as catechin (+), rutin, hyperoside, naringin, naringenin, and genistein, were separated, identified, and quantified by HPLC-DAD chromatography, for the first time, from romanian basil hybrids. The main flavonoid of the extracts was found to be naringin which is present in the highest amount (26.18 mg/kg) in "Aromat de Buzau" (O. basilicum) methanolic extract. These results suggest that dietary intake of these new hybrids can be a source of antioxidant compounds.

Antifungal, Antitumoral and Antioxidant Potential of the Danube Delta Nymphaea alba Extracts.

This study aimed to explore for the first time the biological properties such as antifungal, antitumoral and antioxidant of Danube Delta Nymphaea alba (N. alba) leaf and root methanolic extracts. The toxicity studies of N. alba extracts showed no inhibitory effect on wheat seed germination by evaluating the most sensitive physiological parameters (Germination %, Germination index, Vigor index) and using confocal laser scanning microscopy images. The analyzed extracts were found to have high antifungal activity against Candida glabrata with MIC values of 1.717 µg/mL for leaf and 1.935 µg/mL for root. The antitumor activity of the both extracts against A2780/A2780cisR ovarian, LNCaP prostate and MCF-7 breast cancer cells was promising with IC50 values ranging from 23-274 µg/mL for leaf and 18-152 µg/mL for root, and the combination of N. alba extracts with cisplatin showed a synergistic effect (coefficient of drug interaction <1). The antioxidant properties were assessed by ß-carotene bleaching, ABTS and FRAP assays and cyclic voltammetry. Quercetin, the most prominent antioxidant, was quantified in very good yields by spectroelectrochemical assay.

Utilization of enzyme extract self-encapsulated within polypyrrole in sensitive detection of catechol.

Utilization of polyphenol oxidases (laccase, tyrosinase) in biosensor technology is an efficient approach towards phenol detection, which is significant in numerous fields such as environmental monitoring, food industry etc. The use of crude extract instead of pure enzyme eliminates the need for costly and laborious processes of enzyme separation and purification. This study employs polyphenol oxidase extract, biosynthesized by white-rot fungi Trametes pubescens (TP) for the development of amperometric biosensors for catechol detection. The catalytic activity of the crude extract was firstly used to induce the bio-synthesis of conducting polymer - polypyrrole (Ppy), resulting in the self-encapsulation of the enzyme extract within the conducting material. The viability and biological integrity of the enzyme extract was preserved after the synthesis and was able to efficiently detect phenolic compounds such as catechol. Comparative evaluations between the biosynthesized Ppy based biosensor (bio-Ppy) and the biosensor based on bio-PPy with additional enzyme extract (bio-Ppy-TP) were performed. Lastly, the performance of these two biosensors was compared with that of a third one, based on chemically synthesized Ppy with enzyme extract (chem-Ppy-TP). All three types of biosensors proved high efficiency for catechol detection at low concentration (1-60 µM) and were employed for real sample detection in fruit wines showing linear correlation with the spectrophotometric results obtained with the Folin-Ciocalteau standard test.

Cell-assisted synthesis of conducting polymer - polypyrrole - for the improvement of electric charge transfer through fungal cell wall.

In this research we report the biological synthesis of electrically conducting polymer - Polypyrrole (Ppy). Cell-assisted enzymatic polymerization/oligomerization of Ppy was achieved using whole cell culture and cell-free crude enzyme extract from two white-rot fungal cultures. The selected fungal strains belong to Trametes spp., known laccase producers, commonly applied in bioremediation and bioelectrochemical fields. The biocatalytic reaction was initiated in situ through the copper-containing enzymes biosynthesized within the cell cultures under submerged aerobe cultivation conditions. The procedure was inspired by successful reports of laccase-catalyzed pyrrole polymerization. The usage of whole culture and/or crude enzyme extract has the advantage of overcoming enzyme purification and minimizing the liability of enzyme inactivation through improved stability of enzymes in their natural environment. Spectral and electrochemical techniques (UV-vis spectroscopy, infrared spectroscopy; cyclic voltammetry (CV)) and pH measurements provided insight into the evolution of pyrrole polymerization/oligomerization and the electrochemical features of the final product. Microscopy techniques (optical microscopy and scanning electron microscopy (SEM)) were primary tools for visualization of the formed Ppy particles. The relevance of our research is twofold: Ppy prepared in crude enzyme extract results in enzyme encapsulated within Ppy and/or Ppy-modified fungal cells can be formed when polymerization occurs in whole cell culture. The route of biocatalysis can be chosen according to the desired bioelectrochemical application. The reported study focuses on the improvement of charge transfer through the fungal cell membrane and/or cell wall by modification of the fungal cells with conducting polymer - polypyrrole.

Modification of Aspergillus niger by conducting polymer, Polypyrrole, and the evaluation of electrochemical properties of modified cells.

The enhancement of bioelectrochemical properties of microorganism by in situ formation of conducting polymer within the cell structures (e.g. cell wall) was performed. The synthesis of polypyrrole (Ppy) within fungi (Aspergillus niger) cells was achieved. Two different Aspergillus niger strains were selected due to their ability to produce glucose oxidase, which initiated the Ppy formation through products of enzymatic reaction. The evolution of Ppy structural features was investigated by absorption spectroscopy, cyclic voltammetry and Fourier transform infrared spectroscopy.