Publications by authors named "Nikolaos Tsafantakis"

Article Synopsis
  • * A total of 53 compounds were annotated, including 22 newly discovered analogues and 4 new homologous series, suggesting significant diversity in crambescin compounds.
  • * The research highlights the effectiveness of combining manual and computational methods for detailed metabolomic analysis, underscoring its potential for high-throughput identification in similar studies.
View Article and Find Full Text PDF

In the last decades, subsp. (roots and flowers) has been over harvested through legal and illegal ways in Greece, due to its extremely high commercial demand, as it is used in industry because of its well-known therapeutic properties. As ex situ cultures of the plant have been already developed, in the current comparative study, the herbal teas (infusions) from both flowers of cowslip growing wild in the Prespa Lake Park (NW Greece), and from ex situ propagated and cultivated plant material, have been investigated, with the ultimate goal of assessing them qualitatively.

View Article and Find Full Text PDF

Pyrrolizidine alkaloids (PA) are secondary metabolites of high toxicological relevance. Several PA quantitative methodologies were developed based on a limited number of certified standards, including time consuming solid phase extraction (SPE) purification steps. Herein, we shed light on the variability of PA in herbal extracts and propose a quantification methodology based on ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) for the evaluation of the total PA content as retronecine-equivalents (RE) directly from crude matrices.

View Article and Find Full Text PDF

(1) Background: Species of the anamorphic genus , are known for their fungicolous lifestyle, making them important mycopathogens in fungiculture. Many morphological, ecological, and molecular phylogenetic studies of the genus have been done to date, but taxonomic uncertainties and challenges still remain. Fungal secondary metabolites, being vastly diverse, are utilised as an extra tool in fungal systematics.

View Article and Find Full Text PDF

(L.) interacts with various microorganisms including arbuscular mycorrhizal fungi (AMF). Recently, the AMF MUCL 41833 has been shown to modulate the metabolome of .

View Article and Find Full Text PDF

As part of our screening program for the discovery of molecules of microbial origin with skin-whitening activity, 142 diverse fungal endophytes from a wide variety of Andalusia arid plants were screened, applying the OSMAC approach. The fungal strains CF-090361 and CF-090766, isolated from xerophytic plants, were selected as the most promising, while phylogenetic analysis revealed that both strains could represent a new species within the genus Comoclathris. The effect of different fermentation conditions on the production of tyrosinase inhibitory activity was examined, in order to identify the optimum cultivation conditions.

View Article and Find Full Text PDF

Natural hydroxynaphthoquinone enantiomers (HNQs) are well-described pharmaceutical and cosmeceutical agents especially present in the roots of (L.) Tausch, a species native to the Mediterranean region. In this work, eco-friendly natural deep eutectic solvents (NaDESs) were developed for the selective extraction of these compounds.

View Article and Find Full Text PDF

is recognized for its therapeutic properties, which are attributed to the production of different metabolites. This plant interacts with various microorganisms, including the root symbiotic arbuscular mycorrhizal fungi (AMF). Whether these fungi play a role in the metabolism of is unknown.

View Article and Find Full Text PDF

The fungal strain was isolated from a soil sample collected in Giza province, Egypt, and was identified as   based on phenotypic and genotypic data. The ethyl acetate extract of the fungal strain exhibited promising activity levels against several pathogenic test organisms and through a series of H NMR guided chromatographic separations, a new α-pyrone-C-lyxofuranoside () along with four known compounds (-) were isolated. The planar structure of the new metabolite was elucidated by detailed analysis of its 1D/2D NMR and HRMS/IR/UV spectroscopic data, while the relative configuration of the sugar moiety was determined by a combined study of NOESY and coupling constants data, with the aid of theoretical calculations.

View Article and Find Full Text PDF

Alkannin and shikonin (A/S) are enantiomeric naphthoquinones produced in the roots of certain plants from the Boraginaceae family such as spp. and spp. They possess antimicrobial, anti-tumoral and wound healing properties.

View Article and Find Full Text PDF

The present study describes the peculiar phytochemical characteristics of bergamots cultivated in distinct islands of the Ionian Sea. Ultrahigh-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) supported by 1 and 2D NMR spectroscopy was used for unambiguous metabolic profiling of albedo, flavedo and juice samples. Profile differences were determined using a multi-analytical clustering approach based on high-performance thin-layer chromatography fingerprints and UHPLC-HRMS data.

View Article and Find Full Text PDF

2,4-Dichlorophenol (2,4-DCP) is a ubiquitous environmental pollutant categorized as a priority pollutant by the United States (US) Environmental Protection Agency, posing adverse health effects on humans and wildlife. Bioremediation is proposed as an eco-friendly, cost-effective alternative to traditional physicochemical remediation techniques. In the present study, fungal strains were isolated from marine invertebrates and tested for their ability to biotransform 2,4-DCP at a concentration of 1 mM.

View Article and Find Full Text PDF

: A main cellular functional module that becomes dysfunctional during aging is the proteostasis network. In the present study, we show that benzoic acid derivatives isolated from promote the activity of the two main protein degradation systems, namely the ubiquitin-proteasome (UPP) and especially the autophagy-lysosome pathway (ALP) in human foreskin fibroblasts. Our findings were further supported by in silico studies, where all compounds were found to be putative binders of both cathepsins B and L.

View Article and Find Full Text PDF

In the course of a primary screening of 614 microbial actinomycete extracts for the discovery of tyrosinase inhibitors, the EtOAc extract of the fermentation broth of the strain Streptomyces sp. CA-129531 isolated from a Martinique sample, exhibited in cell free and cell-based assays the most promising activity (IC value of 63 μg/mL). Scaled-up production in a bioreactor led to the isolation of one new trichostatic acid analogue, namely trichostatic acid B (1), along with six known trichostatin derivatives (2-7), four diketopiperazines (8-11), two butyrolactones (12-13) and one hydroxamic acid siderophore (14).

View Article and Find Full Text PDF

has been an important dietary source and a traditionally used medicinal plant. Given the promising health-promoting properties of this plant, a comparative toxicological assessment and antioxidant bioevaluation of extracts from different parts of the plant were carried out in relation to their chemical profile. Toxicity was examined at multiple endpoints using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), Comet and the H2AX In-Cell Western Assay, while hyphenated ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) analysis was carried out to identify main constituents.

View Article and Find Full Text PDF

Introduction: Mediterranean plants are characterised by a high content of bioactive secondary metabolites that play important roles in plant-plant interactions as plant growth regulators and could be useful for the development of new eco-friendly herbicides.

Objective: An NMR-based metabolomics approach was reported to seek selective phytotoxic plant extracts and putative plant-derived active molecules.

Methods: Plant extracts derived from five Mediterranean donor species (Pistacia lentiscus, Bellis sylvestris, Phleum subulatum, Petrohrhagia saxifraga and Melilotus neapolitana) were used to treat the hydroponic cultures of three receiving plants (Triticum durum, Triticum ovatum and Avena fatua).

View Article and Find Full Text PDF

From a large screening of microbial extracts for the discovery of proteasome modulating natural products, the fungal strain Cercospora sp. (CF-223709) was selected as the most promising for further investigation. Different liquid cultures of the strain were initially screened for their anti-oxidant activity (DPPH, ABTS) and for their cytotoxicity against the A2058, HepG2 and CCD25sk cell lines.

View Article and Find Full Text PDF

It is well known that terrestrial environments host an immense microbial biodiversity. Exposed to different types of stress, such as UV radiation, temperature fluctuations, water availability and the inter- / intra-specific competition for resources, terrestrial microorganisms have been evolved to produce a large spectrum of bioactive molecules. Bacteria, archaea, protists, fungi and algae have shown a high potential of producing biomolecules for pharmaceutical or other industrial purposes as they combine a sustainable, relatively low-cost and fast-production process.

View Article and Find Full Text PDF

Six oleanane saponins were isolated for the first time from leaves of Bellis sylvestris Cyr., the southern daisy. Their structures were established by the extensive use of 2D-NMR experiments, including COSY, TOCSY, NOESY, HSQC, HMBC, CIGAR, H2BC, and HSQC-TOCSY, along with Q-TOF HRMS² analysis.

View Article and Find Full Text PDF

Eight flavonoid C-glycosides, including three new analogues, have been isolated from leaf and root methanolic extracts of Petrorhagia velutina, a Mediterranean herbaceous plant. The antiproliferative activity against human hepatoblastoma cancer cell line HepG2 has been analyzed by the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) test. Isoorientin (4) significantly reduces the proliferation of HepG2 cells as determined by the complete conversion of the tetrazolium probe into formazan after 48 h of exposure.

View Article and Find Full Text PDF

In this investigation the phytochemical study of chlorophyll derivatives from leaf extract of Petrorhagia velutina, a eurimediterranean plant species typical of macchia vegetation is reported. A new pheophorbide, as well as nine other chlorophyll derivatives were isolated and their structures determined predominantly based on 1D and 2D NMR methods. The phytotoxicity against Raphanus sativus L.

View Article and Find Full Text PDF