Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae . Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae . Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris ). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium . Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae . Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae ( e.g. , Cosmosporella , Macroconia , Microcera ). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium . To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa ( act1 , CaM , his3 , rpb1 , rpb2 , tef1 , tub2 , ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella ) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [ F. dimerum species complex (SC)], Cyanonectria ( F. buxicola SC), Geejayessia ( F. staphyleae SC), Neocosmospora ( F. solani SC) or Rectifusarium ( F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).

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Isoquinoline alkaloids, an important class of N-based heterocyclic compounds, have attracted considerable attention from researchers worldwide since the early 19th century. Over the past 200 years, many compounds from this class were isolated, and most of them and their analogs possess various bioactivities. In this review, we survey the updated literature on bioactive alkaloids and highlight research achievements of this alkaloid class during the period of 2014-2018. We reviewed over 400 molecules with a broad range of bioactivities, including antitumor, antidiabetic and its complications, antibacterial, antifungal, antiviral, antiparasitic, insecticidal, anti-inflammatory, antioxidant, neuroprotective, and other activities. This review should provide new indications or directions for the discovery of new and better drugs from the original naturally occurring isoquinoline alkaloids.

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As acetylcholinesterase (AChE) inhibitors are an important therapeutic strategy in Alzheimer's disease, efforts are being made in search of new molecules with anti-AChE activity. The fact that naturally-occurring compounds from plants are considered to be a potential source of new inhibitors has led to the discovery of an important number of secondary metabolites and plant extracts with the ability of inhibiting the enzyme AChE, which, according to the cholinergic hypothesis, increases the levels of the neurotransmitter acetylcholine in the brain, thus improving cholinergic functions in patients with Alzheimer's disease and alleviating the symptoms of this neurological disorder. This review summarizes a total of 128 studies which correspond to the most relevant research work published during 2006-2012 (1st semester) on plant-derived compounds, plant extracts and essential oils found to elicit AChE inhibition.

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Background and aims The amount of DNA in an unreplicated gametic chromosome complement is known as the C-value and is a key biodiversity character of fundamental significance with many practical and predictive uses. Since 1976, Bennett and colleagues have assembled eight compilations of angiosperm C-values for reference purposes and subsequently these have been pooled into the Angiosperm DNA C-values Database (http://data.kew.org/cvalues/). Since the last compilation was published in 2005, a large amount of data on angiosperm genome size has been published. It is therefore timely to bring these data together into a ninth compilation of DNA amounts. Scope The present work lists DNA C-values for 2221 species from 151 original sources (including first values for 1860 species not listed in previous compilations). Combining these data with those published previously shows that C-values are now available for 6287 angiosperm species. Key findings Analysis of the dataset, which is by far the largest of the nine compilations published since 1976, shows that angiosperm C-values are now being generated at the highest rate since the first genome sizes were estimated in the 1950s. The compilation includes new record holders for the smallest (1C = 0·0648 pg in Genlisea margaretae) and largest (1C = 152·23 pg in Paris japonica) genome sizes so far reported, extending the range encountered in angiosperms to nearly 2400-fold. A review of progress in meeting targets set at the Plant Genome Size meetings shows that although representation for genera, geographical regions and some plant life forms (e.g. island floras and parasitic plants) has improved, progress to increase familial representation is still slow. In terms of technique it is now clear that flow cytometry is soon likely to become the only method available for plant genome size estimations. Fortunately, this has been accompanied by numerous careful studies to improve the quality of data generated using this technique (e.g. design of new buffers, increased awareness and understanding of problems caused by cytosolic inhibitors). It is also clear that although the speed of DNA sequencing continues to rise dramatically with the advent of next-generation and third-generation sequencing technologies, 'complete genome sequencing' projects are still unable to generate accurate plant genome size estimates.

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This review focuses on recent developments in the use of natural products as therapeutics for Alzheimer's disease. The compounds span a diverse array of structural classes and are organized according to their mechanism of action, with the focus primarily on the major hypotheses. Overall, the review discusses more than 180 compounds and summarizes 400 references.

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