Rosmarinic acid and Ulvan from terrestrial and marine sources in anti-microbial bionanosystems and biomaterials

In order to increase their sustainability, antimicrobial renewable molecules are fundamen-tal additions to consumer goods. Rosmarinic acid is extracted from several terrestrial plants and represents an effective anti-microbial agent. Ulvan, extracted from algae, is an anti-microbial poly-saccharide. The present review is dedicated to discussing the sources and the extraction methodologies for obtaining rosmarinic acid and ulvan. Moreover, the preparation of bioanosystems, inte-grating the two molecules with organic or inorganic substrates, are reviewed as methodologies to increase their effectiveness and stability. Finally, the possibility of preparing functional biomaterials and anti-microbial final products is discussed, considering scientific literature. The performed analysis indicated that the production of both molecules is not yet performed with mature industrial technologies. Nevertheless, both molecules could potentially be used in the packaging, biomedical, pharmaceutical, cosmetic, sanitary and personal care sectors, despite some research being required for developing functional materials with specific properties to pave the way for many more applications

Ulva intestinalis extract acts as biostimulant and modulates metabolites and hormone balance in basil (Ocimum basilicum l.) and parsley (petroselinum crispum l.)

Natural elicitors from macroalgae may affect plant secondary metabolites. Ulvan is a sulfated heteropolysaccharide extracted from green seaweed, acting as both a plant biotic protecting agent, and a plant elicitor, leading to the synthesis of signal molecules. In this work, the aqueous extract of Ulva intestinalis L., mainly composed of ulvan, was used as foliar-spraying treatment and its eliciting effect was investigated in basil (Ocimum basilicum L.) and parsley (Petroselinum crispum L.). Antioxidant metabolites (polyphenols and carotenoids), volatile compounds (both in headspace emissions and hydrodistilled essential oils), and hormones (jasmonic acid, salicylic acid, salicylic acid 2-O--D-glucoside, abscisic acid, and azelaic acid) were quantified. The foliar-spraying treatment with U. intestinalis extract increased salicylic acid and its -glucoside in parsley; in basil, it induced the accumulation of jasmonic and abscisic acids, indicating the presence of a priming effect. In basil, the elicitation caused a change of the essential oil (EO) chemotype from methyl eugenol/eugenol to epi--cadinol and increased sesquiterpenes. In parsley EO it caused a significant accumulation of 1,3,8- p-menthatriene, responsible of the typical “parsley-like” smell. In both species, the phenylpropanoids decreased in headspace and EO compositions, while the salicylic acid concentration increased; this could indicate a primarily defensive response to U. intestinalis extract. Due to the evidenced significant biological activity, U. intestinalis extract used as an elicitor may represent a suitable tool to obtain higher amounts of metabolites for optimizing plant flavor metabolite

Brown alga Ascophyllum nodosum extract-based product, Dalgin Active®, triggers defense mechanisms and confers protection in both bread and durum wheat against Zymoseptoria tritici

International audienceAlternative control strategies are increasingly encouraged to develop sustainable crop protection. In this aim, we assessed the ability of Dalgin Active ® , an Ascophyllum nodosum extract-based product, to induce resistance in bread wheat and durum wheat against Zymoseptoria tritici, a major fungal pathogen on these crops. Foliar application of the product provided a strong and significant reduction of disease intensity on both wheat species without any direct effect against the pathogen. Infection process monitoring revealed that Dalgin Active ® did not prevent fungal epiphytic growth and leaf colonization, but its application results in an inhibition of sporulation as well as fungal cell wall-degrading enzyme and protease activities. During the early stages of infection, Dalgin Active ® activated several plant defense markers on both wheat species, including PR protein, antioxidant metabolism, phenylpropanoid, and octadecanoid-based pathways. Although few differences were recorded, the induced defense reaction patterns were overall similar in both wheat species, suggesting that Dalgin Active ® could be used to biocontrol Z. tritici on both crops