Stefan Martens

Fondazione Edmund Mach - Istituto Agrario San Michele All'Adige | Fondazione Mach · Department of Food Quality and Nutrition (DQAN)

Background: Flavonoids are plant specialised metabolites, which derive from phenylalanine and acetate metabolism. They possess a variety of beneficial characteristics for plants and humans. Several modification steps in the synthesis of tricyclic flavonoids cause for the amazing diversity of flavonoids in plants. The 2 oxoglutarate dependent dioxyg...

Origanum vulgare L. subsp. hirtum (commonly known as Greek oregano) is a perennial species of the Lamiaceae family that counts numerous applications in the food and pharmaceutical industry. The exploitation of Greek oregano germplasm lies in its unique diversity in secondary metabolites, which are accumulated in the aerial parts of the plant. For t...

Citrus fruits are one of the most important fruits in the global food industry due to their unique taste and nutritional benefits. Herein, we characterize the physicochemical and bioactive attributes of twenty-nine Greek citrus accessions, including oranges, mandarins/clementines, lemons, bergamot, citrons and lime along with twenty-seven highly co...

Fruit development involves exocarp color evolution. However, signals that control this process are still elusive. Differences between dark-red and bicolored sweet cherry cultivars rely on MYB factor gene mutations. Color evolution in bicolored fruits only occurs on the face receiving sunlight, suggesting the perception or response to color-inducing...

Root chicory ( Cichorium intybus L. var. sativum ) is used to extract inulin, a fructose polymer used as a natural sweetener and prebiotic. However, bitter tasting sesquiterpene lactones, giving chicory its known flavour, need to be removed during inulin extraction. To avoid this extraction and associated costs, recently chicory variants with a low...

Narrowband green (G), blue (B), red (R), and polychromatic (W ‒ R:G:B, 1:1:1) lights were supplemented (250 µmol photon m‒2 s‒1; 5 h d−1; 21 d) to ambient light with Light Emitting Diodes (LED) in green- (‘Tigullio’; TI) and red-leafed (‘Red Rubin’; RR) sweet basil (Ocimum basilicum L.) plants. The aim of this work was to evaluate LED-triggered var...

Lemonato' is a Greek peach melting-flesh white-flesh cultivar with high nutritional value highly appreciated by the consumers. This study aimed to evaluate the effect of pre-harvest foliar calcium application on fruit quality, primary metabolite profile, antioxidant activity, total phenolic content, and phenolic profile of the 'Lemonato' peach, clo...

Dill (Anethum graveolens L.) is an aromatic herb widely used in the food industry, with several commercial cultivars available with different qualitative characteristics. Commercial cultivars are usually preferred over landraces due to their higher yield and also the lack of improved landraces than can be commercialized. In Greece, however, traditi...

Primula veris subsp. veris L. is a perennial herbaceous and medicinal plant species the roots and flowers of which are a source of valuable pharmaceutical raw materials. The plant tissues are used to produce expectorant and diuretic drugs due to their high content of triterpene saponins and phenolic glycosides. Underground roots of P. veris can be...

Sieboldin is a specialised secondary metabolite of the group of dihydrochalcones (DHC), found in high concentrations only in some wild Malus species, closely related to the domesticated apple ( Malus × domestica L.). To date, the first committed step towards the biosynthesis of sieboldin remains unknown. In this study, we combined transcriptomic an...

Abscisic acid (ABA) plays a key role in the ripening process of non-climacteric fruits, triggering pigment production, fruit softening, and sugar accumulation. Transcriptomic studies show that ABA modifies the expression of several ripening-related genes, but to date, the epigenetic approach has not been utilized to characterize the role of ABA dur...

Phloridzin is the most abundant polyphenolic compound in apple (Malus x domestica Borkh.), which results from the action of a key phloretin‐specific UDP‐2′‐O‐glucosyltransferase (MdPGT1). Here, we simultaneously assessed the effects of targeting MdPGT1 by conventional transgenesis and CRISPR/Cas9‐mediated genome editing. To this end, we conducted t...

Apple (Malus) and pear (Pyrus) are economically important fruit crops well known for their unique textures, flavours, and nutritional qualities. Both genera are characterised by a distinct pattern of secondary metabolites, which directly affect not only resistance to certain diseases, but also have significant impacts on the flavour and nutritional...

Sideritis euboea is a perennial medicinal, local endemic species to mountainous areas of Central and Southern Evia Island (Greece) with isolated populations threatened with extinction. In this context, a genetic and phytochemical survey has been performed to evaluate the present status of S. euboea inter- and intra-population diversity in three mou...

The present study aims to find efficient alternatives to synthetic anthelmintics among ethno-veterinary herbs. Ascaridia galli eggs isolated from the worm uterus were exposed in vitro to methanolic extracts (ME) of nine plant species such as Achillea millefolium (AM), Artemisia absinthium (AA), Artemisia vulgaris (AV), Cicerbita alpina (CA), Cichor...

Citrus fruits are products of great market values, as used by the juice industry in huge quantities. The juice industry processes millions of tons of citrus fruits per year, but only the pulp is utilized, whereas peels, seeds, and membrane residues are mostly discarded. This generates vast amounts of byproducts (>100 million tons/year), since the p...

Profitable hydroponic production requires high quality fresh water, which is often not available for agricultural use, while desalinisation of salty water is an expensive and unsustainable technology. In the present study, we assessed the effect of mild salinity stress during the soilless cultivation of fresh peppermint and spearmint in the floatin...

Previous studies indicate that bilberry with high amounts of phenolic compounds can inhibit carcinogenic processes of colorectal cancer in vitro and in vivo. However, no studies have focused on the effects of bilberry on oral cancer. In this study, we aimed to examine the effects of bilberry powder on oral squamous cell carcinoma (OSCC) cells using...

Bananas ( Musa ) are non-grass, monocotyledonous, perennial plants that are well known for their edible fruits. Their cultivation provides food security and employment opportunities in many countries. Banana fruits contain high levels of minerals and phytochemicals, including flavonoids, which are beneficial for human nutrition. To broaden the know...

Gibberellin (GA) negatively affects color evolution and other ripening-related processes in non-climacteric fruits. The bioactive GA, gibberellic acid (GA 3 ), is commonly applied at the light green-to-straw yellow transition to increase firmness and delay ripening in sweet cherry ( Prunus avium L.), though causing different effects depending on th...

Parsley ( Petroselinum crispum ) aromatic, edible leaves are used fresh or dried as a herb, but also for their pharmaceutical properties. Given the profound concern to high nutritious and pharmaceutical value of superior plant’s germplasm, a survey is presented in this study on the phenotypic, genetic and phytochemical characterization of fifteen G...

The aim of the present study was to investigate the impact of exogenous melatonin (0. 5 mM) application through pre-harvest foliar spray and postharvest immersion, alone or in combination, on ripening parameters of sweet cherry (cv. Ferrovia) fruit and their relationship with bioactive compounds and gene expression at harvest as well after cold sto...

Peels are major byproducts of the juice processing industry. Citrus peels are composed of two tissues, namely the flavedo (outer layer) and the albedo (inner layer). Here, flavedo and albedo were obtained from the peel of grapefruit cv. ‘Star ruby’, lemon cv. ‘Akragas’, and sweet orange cvs. ‘Tarocco’, ‘Sanguinello’ and ‘Moro’. Freeze dried flavedo...

In sweet cherry, as in most non-climacteric species, abscisic acid (ABA) plays a major role in the control of fruit ripening and color development. Although the ABA treatment of sweet cherry fruits has been reported to upregulate anthocyanin pathway-related genes or ABA pathway-related genes, the temporality of molecular and physiological events oc...

Cistus creticus L. subsp. creticus (rockrose) is a shrub widespread in Greece and the Mediterranean basin and has been used in traditional medicine as herb tea for colds, for healing and digestive hitches, for the treatment of maladies, as perfumes, and for other purposes. Compounds from its flavonoid fraction have recently drawn attention due to a...

The present study investigated the potential of fresh peppermint (Mentha × piperita L.) and spearmint (Mentha spicata L.) production on a floating raft system combined with a commercial protein hydrolysate supplement (Amino16®) in a nutrient solution aiming to improve plant product quality. Three levels of the protein hydrolysate solution (0, 0.25...

In this study we describe the crystal structures of the apoform, the binary and the ternary complexes of a double bond reductase from Malus domestica L. (MdDBR) and explore a range of potential substrates. The overall fold of MdDBR is similar to that of the medium chain reductase/dehydrogenase/zinc-dependent alcohol dehydrogenase-like family. Struc...

The present study aimed to investigate the effects of alcoholic fermentation on the physicochemical and phytochemical characteristics of the tissues flavedo and albedo from five citrus fruits, namely grapefruit (Citrus paradisi), lemon (Citrus limon), and sweet oranges (Citrus sinensis) cvs. ‘Tarocco’, ‘Washington navel’, and ‘Moro’. The tissues we...

Gibberellin (GA) negatively affects color evolution and other ripening-related processes in non-climacteric fruits. The bioactive GA, gibberellic acid (GA 3 ), is commonly applied at the light green-to-straw yellow transition to increase firmness and delay ripening in sweet cherry ( Prunus avium L.), though causing different effects depending on th...

Key message This work provides the first system-wide datasets concerning metabolic changes in calcium-treated fruits, which reveal that exogenously applied calcium may specifically reprogram sweet cherry development and ripening physiognomy. Abstract Calcium modulates a wide range of plant developmental processes; however, the regulation of fruit...

The current study characterizes the physicochemical, sensory and bioactive compound traits of twenty-two sweet cherry accessions, namely breeding lines, landraces and modern cultivars, embodying the majority of Greek germplasm. The evaluated accessions differ in several quality traits including colour parameters and textural properties as well as s...

Processing citrus fruits into juice generates large amounts of by-products, mainly pomaces. This study aimed to perform a comprehensive analysis of the composition in phenolic compounds, carotenoids, and volatile organic compounds (VOCs) of juices and pomaces of four citrus fruits from Southern Italy, i.e., mandarin, lemon, orange, and bergamot. Ju...

Natural products comprise a rich reservoir for innovative drug leads and are a constant source of bioactive compounds. To find pharmacological targets for new or already known natural products using modern computer-aided methods is a current endeavor in drug discovery. Nature’s treasures, however, could be used more effectively. Yet, reliable pipel...

Major-effect candidate genes identified in cultivated strawberry (Fragaria × ananassa Duch.) for ellagic acid deoxyhexoside and pelargonidin-3-O-malonylglucoside biosynthesis, key polyphenolic compounds Abstract Strawberries are rich in polyphenols which impart health benefits when metabolized by the gut microbiome, including anti-inflammatory, neu...

Apple (Malus domestica Borkh) is an important fruit crop cultivated in a broad range of environmental conditions. Apple fruit ripening is a physiological process, whose molecular regulatory network response to different environments is still not sufficiently investigated and this is particularly true of the peel tissue. In this study, the influence...

Natural products comprise a rich reservoir for innovative drug leads and are a constant source of bioactive compounds. To find pharmacological targets for new or already known natural products using modern computer-aided methods is a current endeavor in drug discovery. Nature’s treasures, however, could be used more effectively. Yet, reliable pipel...

Natural products comprise a rich reservoir for innovative drug leads and are a constant source of bioactive compounds. To find pharmacological targets for new or already known natural products using modern computer-aided methods is a current endeavor in drug discovery. Nature's treasures, however, could be used more effectively. Yet, reliable pipel...

An increase in the spread of antibiotic-resistant opportunistic microorganisms causes serious problems in the treatment of purulent infections, burns, and trophic ulcers. We tested the antimicrobial activity in vivo of three polyphenols, Resveratrol, Dihydroquercetin (Taxifolin), and Dihydromyricetin (Ampelopsin) from Norway spruce bark to promote...

Background: Rain-induced fruit cracking is a major physiological problem in most sweet cherry cultivars. For an in vivo cracking assay, the 'Christensen method' (cracking evaluation following fruit immersion in water) is commonly used; however, this test does not adequately simulate environmental conditions. Herein, we have designed and evaluated...

Citrus are fruit crops that are widely cultivated in Southern Italy. The phytochemical profile of citrus depends on the species, the tissue and the ripening stage. This study aimed to perform a comprehensive analysis of the phenolic compounds and carotenoids from four citrus species cultivated in the region of Sicily, Southern Italy, between and wi...

Background: Rain-induced fruit cracking is a major physiological problem in most sweet cherry cultivars. For an in vivocracking assay, the ‘Christensen method’ (cracking evaluation following fruit immersion in water) is commonly used; however, this test does not adequately simulate environmental conditions.Herein, we have designed and evaluated a c...

Despite the application of girdling technique for several centuries, its impact on the metabolic shifts that underly fruit biology remains fragmentary. To characterize the influence of girdling on sweet cherry (Prunus avium L.) fruit development and ripening, second-year-old shoots of the cultivars ‘Lapins’ and ‘Skeena’ were girdled before full blo...

This study aimed to evaluate the effects of fermentation with lactic acid bacteria (LAB) on organic acids, ascorbic acid, phenolic compounds, anthocyanins, and carotenoids of sweet orange (Citrus sinensis) juices. Juices from ‘Tarocco’ and ‘Washington navel’ oranges were fermented at 30 °C for 48 h with L. plantarum, L. rhamnosus, L. paracasei, and...

Tobacco is an economically important crop with leaves that are a significant source of aromatic, bioactive compounds such as phenolics and alkaloids. In the present study un- biased transcriptomics and metabolomics approaches were employed to identify and quantify individual changes in transcript and metabolite profiles in leaves of three oriental...

Background: Rain-induced fruit cracking is a major physiological problem in most sweet cherry cultivars. For an in vivo cracking assay, the ‘Christensen method’ (cracking evaluation following fruit immersion in water) is commonly used; however, this test has been questioned. Herein, we have designed and evaluated a cracking protocol, named ‘Waterfa...

Heat and calcium treatments are used to improve postharvest fruit longevity; however, the exact mechanism remains poorly understood. To characterize the impact of these treatments on sweet cherries metabolism, ‘Lapins’ fruits were treated with heat or CaCl2 solutions and their combination and subsequently were exposed at room temperature, for up to...