Phytochemical study of 'tajy' (Handroanthus impetiginosus (Mart.) Mattos) and 'ka'a oveti' (Luehea divaricata Mart.) extracts.

This study explores the phytochemical composition of leaf extracts from Handroanthus impetiginosus (Mart.) Mattos and Luehea divaricata Mart., used in a contraceptive decoction by Mbya-Guarani women. The phytocompounds were identified by gas chro-matography-mass spectrometry, while Fourier-transform infrared spectroscopy, multi-elemental, and thermal analyses were used to characterise plant biomass. Notably, no phytoconstituent supporting the efficacy of these extracts as female contraceptives was found, except for a small amount (0.3%) of sitosterol. Conversely, L. divaricata leaves contained compounds like 1,3-dihydroxyacetone dimer, N-methyl-N-nitroso-2-propanamine, 2-methoxy-N-(2-methoxyethyl)-N-methyl-ethanamine, and 1,3,5-triazine-2,4,6-triamine, potentially exerting cytotoxic, genotoxic, and toxicogenomic effects. Due to the absence of scientific support for the claimed contraceptive efficacy and the presence of safety concerns, we propose an alternative valorisation pathway centred on the presence of phytochemicals exhibiting antimicrobial activity. This proposition is substantiated by their considerable in vitro efficacy against Botrytis cinerea.

Carvacrol Encapsulation in Chitosan-Carboxymethylcellulose-Alginate Nanocarriers for Postharvest Tomato Protection.

Advancements in polymer science and nanotechnology hold significant potential for addressing the increasing demands of food security, by enhancing the shelf life, barrier properties, and nutritional quality of harvested fruits and vegetables. In this context, biopolymer-based delivery systems present themselves as a promising strategy for encapsulating bioactive compounds, improving their absorption, stability, and functionality. This study provides an exploration of the synthesis, characterization, and postharvest protection applications of nanocarriers formed through the complexation of chitosan oligomers, carboxymethylcellulose, and alginate in a 2:2:1 molar ratio. This complexation process was facilitated by methacrylic anhydride and sodium tripolyphosphate as cross-linking agents. Characterization techniques employed include transmission electron microscopy, energy-dispersive X-ray spectroscopy, infrared spectroscopy, thermal analysis, and X-ray powder diffraction. The resulting hollow nanospheres, characterized by a monodisperse distribution and a mean diameter of 114 nm, exhibited efficient encapsulation of carvacrol, with a loading capacity of approximately 20%. Their suitability for phytopathogen control was assessed in vitro against three phytopathogens-Botrytis cinerea, Penicillium expansum, and Colletotrichum coccodes-revealing minimum inhibitory concentrations ranging from 23.3 to 31.3 µg·mL-1. This indicates a higher activity compared to non-encapsulated conventional fungicides. In ex situ tests for tomato (cv. 'Daniela') protection, higher doses (50-100 µg·mL-1, depending on the pathogen) were necessary to achieve high protection. Nevertheless, these doses remained practical for real-world applicability. The advantages of safety, coupled with the potential for a multi-target mode of action, further enhance the appeal of these nanocarriers.

Helichrysum stoechas (L.) Moench Inflorescence Extract for Tomato Disease Management.

Helichrysum stoechas is a singular halophyte that has been shown to have anti-inflammatory, antioxidant, and allelopathic properties. In the work presented herein, we have characterized its inflorescences hydromethanolic extract and assessed its antifungal activity for the pre- and postharvest management of tomato crop diseases. Gas chromatography-mass spectrometry characterization of the extract showed that 4-ethenyl-1,3-benzenediol, 2,3-dihydro-benzofuran, quinic acid, 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-1-benzopyran-4-one, 1,6-anhydro-ß-D-glucopyranose, catechol, scopoletin, and maltol were the main constituents. The co-occurrence of pyranones, benzenediols, and quinic acids as phytoconstituents of H. stoechas extract resulted in promising in vitro minimum inhibitory concentrations of 500, 375, 500, 187.5, 187.5, and 375 µg·mL-1 against mycelia of Alternaria alternata, Colletotrichum coccodes, Fusarium oxysporum f. sp. lycopersici, Rhizoctonia solani, Sclerotinia sclerotiorum, and Verticillium dahliae, respectively. Further, to assess the potential of H. stoechas inflorescence extract for postharvest tomato crop protection, ex situ tests were conducted against C. coccodes, obtaining high protection at a dose of 750 µg·mL-1. Taking into consideration that the demonstrated activity is among the highest reported to date for plant extracts and comparable to that of the synthetic fungicides tested as positive controls, H. stoechas inflorescence extract may be put forward as a promising biorational and may deserve further testing in field-scale studies.

Chemical Constituents and Antimicrobial Activity of a Ganoderma lucidum (Curtis.) P. Karst. Aqueous Ammonia Extract.

Mushroom extracts have shown potential as a source of new antimicrobial agents. This study investigates the chemical profile of an aqueous ammonia extract obtained from the carpophores of Ganoderma lucidum, which grows on Quercus ilex trees, and explores its valorization as a biorational. The major chemical constituents of the extract, identified through gas chromatography-mass spectrometry, include acetamide, oleic acid, 1,2,3,4-butanetetrol, monomethyl azelate, undecane, and palmitic acid. The anti-oomycete and antifungal activity of G. lucidum extract was evaluated against Phytophthora cinnamomi, the primary threat to Quercus spp. in the dehesa biome, as well as three Botryosphaeriaceae fungi. In vitro tests revealed minimum inhibitory concentration (MIC) values of 187.5 µg·mL-1 against P. cinnamomi and 187.5-1000 µg·mL-1 against the fungi. Furthermore, conjugation of the G. lucidum extract with chitosan oligomers (COS) synergistically enhanced its antimicrobial activity, resulting in MIC values of 78.12 and 375-500 µg·mL-1 against P. cinnamomi and the fungi, respectively. These MIC values are among the highest reported to date for natural products against these phytopathogens. Subsequent ex situ testing of the COS-G. lucidum conjugate complex on artificially inoculated Q. ilex excised stems resulted in high protection against P. cinnamomi at a dose of 782 µg·mL-1. These findings support the potential utilization of this resource from the dehesa ecosystem to protect the holm oak, aligning with sustainable and circular economy approaches.

Armeria maritima (Mill.) Willd. Flower Hydromethanolic Extract for Cucurbitaceae Fungal Diseases Control.

The cliff rose (Armeria maritima), like other halophytes, has a phenolics-based antioxidant system that allows it to grow in saline habitats. Provided that antioxidant properties are usually accompanied by antimicrobial activity, in this study we investigated the phytochemicals present in a hydromethanolic extract of A. maritima flowers and explored its antifungal potential. The main phytocompounds, identified by gas chromatography-mass spectrometry, were: hexadecanoic acid, octadecanoic acid, 9-octadecenoic acid, 3-(3,4-dihydroxy-phenyl)-acrylic acid ethyl ester, and benzeneacetaldehyde. The antifungal activity of the extract and its main constituents-alone and in combination with chitosan oligomers-was tested against six pathogenic taxa associated with soil-borne diseases of plant hosts in the family Cucurbitaceae: Fusarium equiseti, F. oxysporum f. sp. niveum, Macrophomina phaseolina, Neocosmospora falciformis, N. keratoplastica, and Sclerotinia sclerotiorum. In in vitro tests, EC90 effective concentrations in the 166-865 µg·mL-1 range were obtained for the chitosan oligomers-A. maritima extract conjugate complexes, lower than those obtained for fosetyl-Al and azoxystrobin synthetic fungicides tested for comparison purposes, and even outperforming mancozeb against F. equiseti. In ex situ tests against S. sclerotiorum conducted on artificially inoculated cucumber slices, full protection was achieved at a dose of 250 µg·mL-1. Thus, the reported results support the valorization of A. maritima as a source of biorationals for Cucurbitaceae pathogens protection, suitable for both organic and conventional agriculture.

Silene uniflora Extracts for Strawberry Postharvest Protection.

Halophytes are gaining considerable attention due to their applications in saline agriculture, phytoremediation, medicine, and secondary metabolite production. This study investigated the bioactive components present in Silene uniflora (sea campion) hydromethanolic extract, and their antimicrobial activity was evaluated both in vitro and ex situ against two strawberry phytopathogens, namely Botrytis cinerea (grey mold) and Colletotrichum nymphaeae (anthracnose fruit rot). The main identified phytochemicals were mome inositol, saturated fatty acid esters, and cyclotetracosane. In vitro tests demonstrated complete inhibition of the growth of B. cinerea and C. nymphaeae at extract concentrations of 1000 and 1500 µg·mL-1, respectively, with an activity comparable to that of fosetyl-Al and substantially higher than that of azoxystrobin. This activity was improved upon conjugation with chitosan oligomers (COS), yielding inhibition values of 750 and 1000 µg·mL-1. The COS-S. uniflora conjugate complexes were then tested as protective treatments for postharvest storage of strawberry fruit, resulting in high protection against artificially inoculated B. cinerea and C. nymphaeae at doses of 3750 and 5000 µg·mL-1, respectively. The reported results open the door to the valorization of this halophyte as a source of biorationals for strawberry protection.

Characterization of Leptoglossus occidentalis Eggs and Egg Glue.

The western conifer seed bug (Leptoglossus occidentalis Heidemann, 1910, Heteroptera: Coreidae) has a significant economic impact due to the reduction in the quality and viability of conifer seed crops; it can feed on up to 40 different species of conifers, showing a clear predilection for Pinus pinea L. in Europe. Its incidence is especially relevant for the pine nut-producing industry, given that the action of this pest insect can reduce the production of pine nuts by up to 25%. As part of ongoing efforts aimed at the design of control strategies for this insect, this work focuses on the characterization (by scanning electron microscopy-energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, and gas chromatography-mass spectroscopy, GC-MS) of the compounds released by these insects during oviposition, with emphasis on the adhesive secretion that holds L. occidentalis eggs together. Elemental analysis pointed to the presence of significant amounts of compounds with high nitrogen content. Functional groups identified by infrared spectroscopy were compatible with the presence of chitin, scleroproteins, LNSP-like and gelatin proteins, shellac wax analogs, and policosanol. Regarding the chemical species identified by GC-MS, eggs and glue hydromethanolic extracts shared constituents such as butyl citrate, dibutyl itaconate, tributyl aconitate, oleic acid, oleamide, erucamide, and palmitic acid, while eggs also showed stearic and linoleic acid-related compounds. Knowledge of this composition may allow advances in new strategies to address the problem caused by L. occidentalis.

Phytochemical Profiling of Sambucus nigra L. Flower and Leaf Extracts and Their Antimicrobial Potential against Almond Tree Pathogens.

Despite extensive research on the chemical composition of elderberries and their numerous uses in pharmaceutical, beverage, and food production, there is still a lack of knowledge about Sambucus nigra leaves and flowers' antimicrobial activity against plant pathogens. In this study, the phytoconstituents of their aqueous ammonia extracts were first characterized by infrared spectroscopy and gas chromatography-mass spectrometry. The major phytocompounds identified in the flower extract were octyl 2-methylpropanoate; 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one; propyl malonic acid; adenine; and 1-methyl-2-piperidinemethanol. Concerning the leaf extract, 1,6-anhydro-ß-D-glucopyranose; oleic acid; 2,1,3-benzothiadiazole; 2,3-dihydro-benzofuran; and 4-((1E)-3-hydroxy-1-propenyl)-2-methoxyphenol and other phenol derivatives were the main constituents. The potential of the extracts to act as bioprotectants was then investigated against three almond tree pathogens: Diaporthe amygdali, Phytophthora megasperma, and Verticillium dahliae. In vitro tests showed higher activity of the flower extract, with EC90 values in the 241-984 µg·mL-1 range (depending on the pathogen) vs. 354-1322 µg·mL-1 for the leaf extract. In addition, the flower extract led to full protection against P. megasperma at a dose of 1875 µg·mL-1 in ex situ tests on artificially-infected excised almond stems. These inhibitory concentrations were lower than those of commercial fungicides. These findings suggest that S. nigra aerial organs may be susceptible to valorization as an alternative to synthetic fungicides for the protection of this important crop.

Valorization of Quercus suber L. Bark as a Source of Phytochemicals with Antimicrobial Activity against Apple Tree Diseases.

Cork, an anatomic adaptation of the bark of Quercus suber L. through its suberization process, finds its main application in the production of bottle stoppers. Its processing results in a large waste stream of cork fragments, granulates, and dust, which may be susceptible to valorization. The work presented here explored the use of its extracts to inhibit the growth of phytopathogenic microorganisms associated with apple tree diseases. The in vitro antimicrobial activity of cork aqueous ammonia extract was assayed against four fungi, viz. Monilinia fructigena and M. laxa (brown rot), Neofussicoccum parvum (dieback), and Phytophthora cactorum (collar and root rot), and two bacteria, viz. Erwinia amylovora and Pseudomonas syringae pv. syringae, either alone or in combination with chitosan oligomers (COS). Effective concentration values of EC90 in the 675-3450 µg·mL-1 range, depending on the fungal pathogen, were obtained in growth inhibition tests, which were substantially improved for the conjugate complexes (340-801 µg·mL-1) as a result of strong synergism with COS. Similar enhanced behavior was also observed in antibacterial activity assays, with MIC values of 375 and 750 µg·mL-1 for the conjugate complexes against P. syringae pv. syringae and E. amylovora, respectively. This in vitro inhibitory activity was substantially higher than those exhibited by azoxystrobin and fosetyl-Al, which were tested for comparison purposes, and stood out among those reported for other natural compounds in the literature. The observed antimicrobial activity may be mainly attributed to the presence of glycerin and vanillic acid, identified by gas chromatography-mass spectroscopy. In the first step towards in-field application, the COS-Q. suber bark extract conjugate complex was further tested ex situ against P. cactorum on artificially inoculated excised stems of the 'Garnem' almond rootstock, achieving high protection at a dose of 3750 µg·mL-1. These results suggest that cork industrial leftovers may, thus, be a promising source of bioactive compounds for integrated pest management.

Multifunctional Nanocarriers Based on Chitosan Oligomers and Graphitic Carbon Nitride Assembly.

In this study, a graphitic carbon nitride and chitosan oligomers (g-C3N4−COS) nanocarrier assembly, which was obtained by cross-linking with methacrylic anhydride (MA), was synthesized and characterized. Its characterization was carried out using infrared spectroscopy, elemental and thermal analyses, and transmission electron microscopy. The new nanocarriers (NCs), with an average particle size of 85 nm in diameter and a 0.25 dispersity index, showed photocatalytic activity (associated with the g-C3N4 moiety), susceptibility to enzymatic degradation (due to the presence of the COS moiety), and high encapsulation and moderate-high release efficiencies (>95% and >74%, respectively). As a proof of concept, the visible-light-driven photocatalytic activity of the NCs was tested for rhodamine B degradation and the reduction of uranium(VI) to uranium(IV). Regarding the potential of the nanocarriers for the encapsulation and delivery of bioactive products for crop protection, NCs loaded with Rubia tinctorum extracts were investigated in vitro against three Vitis vinifera phytopathogens (viz. Neofusicoccum parvum, Diplodia seriata, and Xylophilus ampelinus), obtaining minimum inhibitory concentration values of 750, 250, and 187.5 µg·mL−1, respectively. Their antifungal activity was further tested in vivo as a pruning wound protection product in young 'Tempranillo' grapevine plants that were artificially infected with the two aforementioned species of the family Botryosphaeriaceae, finding a significant reduction of the necrosis lengths in the inner woody tissues. Therefore, g-C3N4-MA-COS NCs may be put forward as a multifunctional platform for environmental and agrochemical delivery applications.

Holm Oak (Quercus ilex subsp. ballota (Desf.) Samp.) Bark Aqueous Ammonia Extract for the Control of Invasive Forest Pathogens.

Holm oak (Quercus ilex subsp. ballota (Desf.) Samp.) bark is a commonly used remedy to treat gastrointestinal disorders, throat and skin infections, hemorrhages, and dysentery. It has also been previously reported that its methanol extracts possess antibacterial activity, which can be related to the richness of Quercus spp. extracts in phenolic compounds, such as flavonoids and tannins. However, there is no information on the antifungal (including oomycete) properties of the bark from Q. ilex or its subspecies (ilex and ballota). In this work, we report the characterization of the aqueous ammonia extract of its bark by FTIR and GC-MS and the results of in vitro and ex situ inhibition tests against three phytopathogens. The main phytochemical components identified were inositols (19.5%), trans-squalene (13%), 4-butoxy-1-butanol (11.4%), gulopyranose (9.6%), lyxose (6.5%), 2,4-dimethyl-benzo[H]quinoline (5.1%), catechol (4.5%), and methoxyphenols (4.2%). The efficacy of the extract in controlling forest phytopathogens was tested in vitro against Fusarium circinatum (responsible for pitch canker of Pinus spp.), Cryphonectria parasitica (which causes chestnut blight), and Phytophthora cinnamomi (which causes 'root and crown rot' in a variety of hosts, including Castanea, conifers, Eucalyptus, Fagus, Juglans, Quercus, etc.), obtaining EC90 values of 322, 295, and 75 µg·mL-1, respectively, much lower than those attained for a commercial strobilurin fungicide (azoxystrobin). The extract was further tested ex situ against P. cinnamomi on artificially inoculated, excised stems of 'Garnem' almond rootstock, attaining complete protection at a dose of 782 µg·mL-1. The results suggest that holm oak bark extract may be a promising source of bioactive compounds against invasive forest pathogens, including the oomycete that is causing its decline, the so-called 'seca' in Spain.

Dwarf Pomegranate (Punica granatum L. var. nana): Source of 5-HMF and Bioactive Compounds with Applications in the Protection of Woody Crops.

While the properties of edible pomegranate varieties have been widely explored, there is little information on ornamental types. In this study, possible alternatives for the valorization of dwarf pomegranate fruits have been explored. The characterization of their hydromethanolic extract by gas chromatography-mass spectrometry evidenced the presence of high contents of 5-hydroxymethylfurfural (a carbon-neutral feedstock for the production of fuels and other chemicals) and ß- and γ-sitosterol stereoisomers. The microbicidal activity of the crude extract, both alone and in a conjugate complex with chitosan oligomers (COS), was investigated against three plant pathogenic microorganisms that cause significant losses in woody crops: Erwinia amylovora, E. vitivora, and Diplodia seriata. In in vitro assays, a strong synergistic behavior was found after conjugation of the bioactive constituents of the fruit extract with COS, resulting in minimum inhibitory concentration (MIC) values of 750 and 375 µg·mL-1 against E. amylovora and E. vitivora, respectively, and an EC90 value of 993 µg·mL-1 against D. seriata. Hence, extracts from the non-edible fruits of this Punicaceae may hold promise as a source of high value-added phytochemicals or as environmentally friendly agrochemicals.

Opportunities for Ivory Nut Residue Valorization as a Source of Nanocellulose Colloidal Suspensions.

Ivory nut seeds have been traditionally exploited in Central and South America for obtaining vegetable ivory. The residues from this industry are susceptible to valorization as a source of fatty acids (by organic extraction) and mannans (by alkaline dissolution and regeneration). Nonetheless, cellulose may also be recovered at the end of this fractionation process by acid hydrolysis and functionalization, with associated advantages over other lignocellulosic sources due to the absence of lignin in the endospermic tissue. In this work, various experimental parameters (sulfuric acid concentration, temperature, and hydrolysis time) were investigated to optimize the processing conditions for preparing stable nanocellulose suspensions after ultrasonication. The most stable nanocellulose gel (1 wt% solid content) was obtained after 4-h hydrolysis at 60 °C with 8 M H2SO4 and was characterized by using complementary tech-niques, including dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), nano-fibril sulfation measurements, vibrational and solid-state nuclear magnetic resonance (CP/MAS 13C-NMR) spectroscopies, and thermal analysis. This nanocellulose hydrogel is susceptible to further utilization in various applications and fields, e.g., in agricul-ture for controlling the release of agrochemicals, in pharmaceutics for developing new dosage forms, and in the treatment of wastewater from the textile and paper industries.

Characterization and Antimicrobial Activity of a Halophyte from the Asturian Coast (Spain): Limonium binervosum (G.E.Sm.) C.E.Salmon.

The work presented herein deals with the characterization and valorization of a halophyte from the cliffs of the Asturian coast: Limonium binervosum (G.E.Sm.) C.E.Salmon (rock sea-lavender). Its biomass and hydromethanolic extracts were studied by elemental and thermal analysis, infrared spectroscopy and gas chromatography-mass spectroscopy. Tetradecanoic acid/esters and 1,2-tetradecanediol were identified in its flower extract, while the leaf extract was rich in linolenic and linoleic acids and their esters, hexadecanoic acid and its esters, and phytol. Both flower and leaf hydromethanolic extracts contained eicosane, sitosterol and tocopherols in significant amounts. With a view to its valorization, the antimicrobial activity of these extracts was investigated against three apple tree and grapevine phytopathogens. Both the hydroalcoholic extracts and their main constituents, alone or in combination with chitosan oligomers (COS), were tested in vitro. A remarkable antibacterial activity was observed for the conjugated complexes of the flower extract with COS, both against Xylophilus ampelinus (MIC = 250 µg·mL-1) and Erwinia amylovora (MIC = 500 µg·mL-1), and complete inhibition of the mycelial growth of Diplodia seriata was found at concentrations <1000 µg·mL-1. In view of these results, this extremophile plant can be put forward as a promising source of bioactive metabolites.

Physicochemical Characterization and Antimicrobial Activity against Erwinia amylovora, Erwinia vitivora, and Diplodia seriata of a Light Purple Hibiscus syriacus L. Cultivar.

Phytochemicals are essential raw materials for the production of formulations that can be helpful in crop protection. In particular, Hibiscus spp., which are often used in traditional medicine, are rich in potential bioactive molecules. This study presents an analysis of the thermal, vibrational, and phytochemical characteristics of a light purple variety of Hibiscus syriacus, using thermal gravimetric and differential scanning calorimetry, Fourier-transform infrared spectroscopy, and gas chromatography-mass spectroscopy techniques. Further, with a view to its valorization, the antimicrobial activity of its extracts has been investigated in vitro against Erwinia amylovora (the phytopathogen responsible for fire blight in apples, pears, and some other members of the family Rosaceae), Erwinia vitivora (the causal agent of the "maladie d'Oléron" in grapevines), and Diplodia seriata (responsible for "Bot canker"). Higher heating values and thermal features showed similarities with kenaf biomass. The main compounds identified in the hydro-methanolic extracts were: in flowers, 1-heptacosanol, heptacosane, 1-tetracosanol, hexadecenoic acid, 9,12,15-octadecatrienoic acid, and 9,12-octadecadienoic acid; and in leaves, the coumarin derivative 4,4,6,8-tetramethyl-2-chromanone, vitamin E, phytol, and sitosterol. MIC values of 500 and 375 µg·mL-1 were obtained against E. amylovora for flower and leaf extracts, respectively, upon conjugation with chitosan oligomers (to improve solubility and bioavailability). In the case of E. vitivora, MIC values of 250 and 500 µg·mL-1, respectively, were registered. Regarding the antifungal activity, EC90 values of 975.8 and 603.5 µg·mL-1, respectively, were found. These findings suggest that H. syriacus (cv. 'Mathilde') may be a promising source of antimicrobials for agriculture.

Activity of Anthracenediones and Flavoring Phenols in Hydromethanolic Extracts of Rubia tinctorum against Grapevine Phytopathogenic Fungi.

In this work, the chemical composition of Rubia tinctorum root hydromethanolic extract was analyzed by GC-MS, and over 50 constituents were identified. The main phytochemicals were alizarin-related anthraquinones and flavoring phenol compounds. The antifungal activity of this extract, alone and in combination with chitosan oligomers (COS) or with stevioside, was evaluated against the pathogenic taxa Diplodia seriata, Dothiorella viticola and Neofusicoccum parvum, responsible for the so-called Botryosphaeria dieback of grapevine. In vitro mycelial growth inhibition tests showed remarkable activity for the pure extract, with EC50 and EC90 values as low as 66 and 88 µg·mL-1, respectively. Nonetheless, enhanced activity was attained upon the formation of conjugate complexes with COS or with stevioside, with synergy factors of up to 5.4 and 3.3, respectively, resulting in EC50 and EC90 values as low as 22 and 56 µg·mL-1, respectively. The conjugate with the best performance (COS-R. tinctorum extract) was then assayed ex situ on autoclaved grapevine wood against D. seriata, confirming its antifungal behavior on this plant material. Finally, the same conjugate was evaluated in greenhouse assays on grafted grapevine plants artificially inoculated with the three aforementioned fungal species, resulting in a significant reduction in the infection rate in all cases. This natural antifungal compound represents a promising alternative for developing sustainable control methods against grapevine trunk diseases.

Antifungal Activity against Botryosphaeriaceae Fungi of the Hydro-Methanolic Extract of Silybum marianum Capitula Conjugated with Stevioside.

Silybum marianum (L.) Gaertn, viz. milk thistle, has been the focus of research efforts in the past few years, albeit almost exclusively restricted to the medicinal properties of its fruits (achenes). Given that other milk thistle plant organs and tissues have been scarcely investigated for the presence of bioactive compounds, in this study, we present a phytochemical analysis of the extracts of S. marianum capitula during the flowering phenological stage (stage 67). Gas chromatography-mass spectroscopy results evidenced the presence of high contents of coniferyl alcohol (47.4%), and secondarily of ferulic acid ester, opening a new valorization strategy of this plant based on the former high-added-value component. Moreover, the application of the hydro-methanolic extracts as an antifungal agent has been also explored. Specifically, their activity against three fungal species responsible for the so-called Botryosphaeria dieback of grapevine (Neofusicoccum parvum, Dothiorella viticola and Diplodia seriata) has been assayed both in vitro and in vivo. From the mycelial growth inhibition assays, the best results (EC90 values of 303, 366, and 355 µg·mL-1 for N. parvum, D. viticola, and D. seriata, respectively) were not obtained for the hydroalcoholic extract alone, but after its conjugation with stevioside, which resulted in a strong synergistic behavior. Greenhouse experiments confirmed the efficacy of the conjugated complexes, pointing to the potential of the combination of milk thistle extracts with stevioside as a promising plant protection product in organic Viticulture.

Cyttaria hariotii E.Fisch. as a promising source of pullulan and Mn(II)-pullulan complexes for Mn-deficiency remediation in winter cereals.

Pullulan, a water-soluble polysaccharide consisting of maltotriose units used in the preparation of edible films and drug delivery, is generally produced from starch by Aureobasidium pullulans (de Bary & Löwenthal) G.Arnaud fungus. In this article, the characterisation of an alternative pullulan source - the stromata of Cyttaria hariotii E.Fisch. fungus - by elemental analysis, infrared spectroscopy and thermal analysis techniques is reported. With a view to a possible valorisation of this pullulan and its derivatives as bioactive formulations in agriculture, low-molecular-weight pullulan (<7 kDa) complexes with Mn(II), suitable for the remediation of Mn-deficiencies in winter cereal by foliar application, were synthesised and characterised by mass spectrometry.

On the Physicochemical Characteristics and Applications of an "Undesirable" Pyrenean Thorny Cushion Dwarf: Echinospartum horridum (Vahl) Roth.

Small evergreen shrubs of the family Fabaceae represent a large proportion of current Mediterranean mountain vegetation. Their low pastoral value and tendency for encroachment makes these plants undesirable. In this paper, the thermal and chemical characteristics of Echinospartum horridum, a thorny cushion-shaped dwarf shrub native to the French Central Massif and the Pyrenees (particularly dominant in the shrublands of the Pyrenees), have been analyzed with a view to its valorization. Although the higher and lower heating values of the biomass from E. horridum met the ISO 17225-2:2014 requirements for its use in pellets, the ash content was slightly above the upper limit, so it would not comply with the normative for its acceptable use as a fuel. Nevertheless, the presence of high added-value flavonoids and lignans in its extracts, which are receiving increasing recent interest as efficient anti-tumor drugs and antivirals, may open the door to the valorization of this shrub for pharmacological applications.

Antifungal Activity against Fusarium culmorum of Stevioside, Silybum marianum Seed Extracts, and Their Conjugate Complexes.

Fusarium head blight (FHB) is a disease that poses a major challenge in cereal production that has important food and feed safety implications due to trichothecene contamination. In this study, the effect of stevioside-a glycoside found in the leaves of candyleaf (Stevia rebaudiana Bertoni)-was evaluated in vitro against Fusarium culmorum (W.G. Smith) Sacc., alone and in combination (in a 1:1 molar ratio) with polyphenols obtained from milk thistle seeds (Silybum marianum (L.) Gaertn). Different concentrations, ranging from 32 to 512 µg·mL-1, were assayed, finding EC50 and EC90 inhibitory concentrations of 156 and 221 µg·mL-1, respectively, for the treatment based only on stevioside, and EC50 and EC90 values of 123 and 160 µg·mL-1, respectively, for the treatment based on the stevioside-polyphenol conjugate complexes. Colony formation inhibition results were consistent, reaching full inhibition at 256 µg·mL-1. Given that synergistic behavior was observed for this latter formulation (SF = 1.43, according to Wadley's method), it was further assessed for grain protection at storage, mostly directed against mycotoxin contamination caused by the aforementioned phytopathogen, confirming that it could inhibit fungal growth and avoid trichothecene contamination. Moreover, seed tests showed that the treatment did not affect the percentage of germination, and it resulted in a lower incidence of root rot caused by the pathogen in Kamut and winter wheat seedlings. Hence, the application of these stevioside-S. marianum seed extract conjugate complexes may be put forward as a promising and environmentally friendly treatment for the protection of cereal crops and stored grain against FHB.