Essential oils (EOs) are a mixture of natural, volatile, and aromatic compounds obtained from plants. In recent years, several studies have shown that some of their benefits can be attributed to their antimicrobial, antioxidant, anti-inflammatory, and also immunomodulatory properties. Therefore, EOs have been proposed as a natural alternative to antibiotics or for use in combination with antibiotics against multidrug-resistant bacteria in animal feed and food preservation. Most of the results come from in vitro and in vivo studies; however, very little is known about their use in clinical studies. A systematic and comprehensive literature search was conducted in PubMed, Embase ® , and Scopus from December 2014 to April 2019 using different combinations of the following keywords: essential oils, volatile oils, antimicrobial, antioxidant, immunomodulation, and microbiota. Some EOs have demonstrated their efficacy against several foodborne pathogens in vitro and model food systems; namely, the inhibition of S. aureus , V. cholerae , and C. albicans has been observed. EOs have shown remarkable antioxidant activities when used at a dose range of 0.01 to 10 mg/mL in cell models, which can be attributed to their richness in phenolic compounds. Moreover, selected EOs exhibit immunomodulatory activities that have been mainly attributed to their ability to modify the secretion of cytokines.

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This paper represents the third contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions, information about the pathology, distribution, hosts and disease symptoms for the treated genera, as well as primary and secondary DNA barcodes for the currently accepted species included in these. This third paper in the GOPHY series treats 21 genera of phytopathogenic fungi and their relatives including: Allophoma , Alternaria , Brunneosphaerella , Elsinoe , Exserohilum , Neosetophoma , Neostagonospora , Nothophoma , Parastagonospora , Phaeosphaeriopsis , Pleiocarpon , Pyrenophora , Ramichloridium , Seifertia , Seiridium , Septoriella , Setophoma , Stagonosporopsis , Stemphylium , Tubakia and Zasmidium . This study includes three new genera, 42 new species, 23 new combinations, four new names, and three typifications of older names.

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Fresh material, type studies and molecular phylogeny were used to clarify phylogenetic relationships of the nine genera Acrocordiella, Blogiascospora, Clypeosphaeria, Hymenopleella, Lepteutypa, Pseudapiospora, Requienella, Seiridium and Strickeria . At first sight, some of these genera do not seem to have much in common, but all were found to belong to the Xylariales , based on their generic types. Thus, the most peculiar finding is the phylogenetic affinity of the genera Acrocordiella, Requienella and Strickeria , which had been classified in the Dothideomycetes or Eurotiomycetes , to the Xylariales . Acrocordiella and Requienella are closely related but distinct genera of the Requienellaceae . Although their ascospores are similar to those of Lepteutypa , phylogenetic analyses do not reveal a particularly close relationship. The generic type of Lepteutypa, L. fuckelii , belongs to the Amphisphaeriaceae . Lepteutypa sambuci is newly described. Hymenopleella is recognised as phylogenetically distinct from Lepteutypa , and Hymenopleella hippophaëicola is proposed as new name for its generic type, Sphaeria (= Lepteutypa) hippophaës. Clypeosphaeria uniseptata is combined in Lepteutypa . No asexual morphs have been detected in species of Lepteutypa. Pseudomassaria fallax , unrelated to the generic type, P. chondrospora , is transferred to the new genus Basiseptospora , the genus Pseudapiospora is revived for P. corni , and Pseudomassaria carolinensis is combined in Beltraniella (Beltraniaceae ). The family Clypeosphaeriaceae is discontinued, because the generic type of Clypeosphaeria, C. mamillana , is a member of the Xylariaceae . The genus Seiridium , of which the sexual morph Blogiascospora is confirmed, is unrelated to Lepteutypa , as is Lepteutypa cupressi . The taxonomy of the cypress canker agents is discussed. The family Sporocadaceae is revived for a large clade of the Xylariales that contains Hymenopleella, Seiridium and Strickeria among a number of other genera. Neotypes are proposed for Massaria fuckelii and Sphaeria hippophaës. Didymella vexata, Seiridium marginatum, Sphaeria corni, Sphaeria hippophaës, Sphaeria seminuda are epitypified, Apiosporina fallax, Massaria occulta, Sphaeria mamillana and Strickeria kochii are lecto- and epitypified. We also provide DNA data for Broomella vitalbae, Cainia desmazieri and Creosphaeria sassafras .

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Background and aims Condensed tannins (also called proanthocyanidins) are widespread polymers of catechins and are essential for the defence mechanisms of vascular plants (Tracheophyta). A large body of evidence argues for the synthesis of monomeric epicatechin on the cytosolic face of the endoplasmic reticulum and its transport to the vacuole, although the site of its polymerization into tannins remains to be elucidated. The aim of the study was to re-examine the cellular frame of tannin polymerization in various representatives of the Tracheophyta. Methods Light microscopy epifluorescence, confocal microscopy, transmission electron microscopy (TEM), chemical analysis of tannins following cell fractionation, and immunocytochemistry were used as independent methods on tannin-rich samples from various organs from Cycadophyta, Ginkgophyta, Equisetophyta, Pteridophyta, Coniferophyta and Magnoliophyta. Tissues were fixed in a caffeine-glutaraldehyde mixture and examined by TEM. Other fresh samples were incubated with primary antibodies against proteins from both chloroplastic envelopes and a thylakoidal chlorophyll-carrying protein; they were also incubated with gelatin-Oregon Green, a fluorescent marker of condensed tannins. Coupled spectral analyses of chlorophyll and tannins were carried out by confocal microscopy on fresh tissues and tannin-rich accretions obtained through cell fractionation; chemical analyses of tannins and chlorophylls were also performed on the accretions. Key results and conclusions The presence of the three different chloroplast membranes inside vacuolar accretions that constitute the typical form of tannin storage in vascular plants was established in fresh tissues as well as in purified organelles, using several independent methods. Tannins are polymerized in a new chloroplast-derived organelle, the tannosome. These are formed by pearling of the thylakoids into 30 nm spheres, which are then encapsulated in a tannosome shuttle formed by budding from the chloroplast and bound by a membrane resulting from the fusion of both chloroplast envelopes. The shuttle conveys numerous tannosomes through the cytoplasm towards the vacuole in which it is then incorporated by invagination of the tonoplast. Finally, shuttles bound by a portion of tonoplast aggregate into tannin accretions which are stored in the vacuole. Polymerization of tannins occurs inside the tannosome regardless of the compartment being crossed. A complete sequence of events apparently valid in all studied Tracheophyta is described.

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Terpene synthases are responsible for the large diversity of terpene carbon skeletons found in plants. The unique, carbocationic reaction mechanism of these enzymes can form multiple products from a single prenyl diphosphate substrate. Two maize genes were isolated that encode very similar sesquiterpene synthases, TPS6 and TPS11, which both produce beta-bisabolene, a common monocyclic sesquiterpene, and beta-macrocarpene, an uncommon bicyclic olefin. Investigation of the reaction mechanism showed that the formation of beta-macrocarpene proceeds via a neutral beta-bisabolene intermediate and requires reprotonation by a proton that may ultimately be abstracted from water. This reprotonation is dependent on the pH and the presence of a Mg(2+) cofactor. Mutational analysis of the enzyme demonstrated that a highly conserved tyrosine residue in the active center of the enzymes is important for the protonation process. TPS6 and TPS11 are transcribed both in leaves and roots of maize, but the respective terpene products were only detected in roots. The expression in roots was up-regulated by herbivore damage to the leaves, suggesting a long distance signal transduction cascade between leaves and roots.

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