The gastrointestinal nematodes (GIN) stand out as an important cause of disease in small ruminant, especially on goat farm. Widespread resistance to synthetic anthelminthics has stimulated the research for alternative strategies of parasite control, including the use of medicinal plants. The present work summarizes the in vitro and in vivo studies of plants with activity against GIN of goats, focusing on the description of chemical constituents related to this effect. This review retrieved 56 scientific articles from 2008 to 2018 describing more than 100 different plant species. The most frequently investigated family was Fabaceae (30.7%). Most in vitro studies on the activity of plant extracts and fractions were carried out with of free-living stages nematodes. In vivo studies were conducted mainly with the use of plants in animal feed and generally showed lower effectiveness compared to in vitro assays. The main plant secondary metabolites associated with anthelmintic effect are condensed tannins, saponin and flavonoids. However, the studies with compounds isolated from plants and elucidation of their mechanisms of action are scarce. Herbal medicines are thought to be promising sources for the development of effective anthelmintic agents.

Introduction: Lauraceae alkaloids are a structurally diverse class of plant specialised secondary metabolites that play an important role in modern pharmacotherapy, being useful as well as model compounds for the development of synthetic analogues. However, alkaloids characterisation is challenging due to low concentrations, the complexity of plant extracts, and long processes for accurate structural determinations. Objective: The use of high-performance thin layer chromatography coupled with desorption electrospray ionisation multistage mass spectrometry (HPTLC DESI-MS n) as a fast tool to identify alkaloids present in Ocotea spixiana extract and evaluate the extract's acaricide activity. Methods: Ocotea spixiana twigs were extracted by conventional liquid-liquid partitioning. HPTLC analysis of the ethyl acetate extract was performed to separate isobaric alkaloids prior to DESI-MS n analysis, performed from MS 3 up to MS 7. The extract's acaricide activity against Rhipicephalus microplus was evaluated by in vitro (larval immersion test) and in silico tests. Results: HPTLC-DESI-MS n analysis was performed to identify a total of 13 aporphine and four benzylisoquinoline-type alkaloids reported for the first time in O. spixiana. In vitro evaluation of the extract and the alkaloid boldine showed significant activity against R. microplus larvae. It was established in silico that boldine had important intermolecular interactions with R. microplus acetylcholinesterase enzyme. Conclusion: The present study demonstrated that HPTLC-DESI-MS n is a useful analytical tool to identify isoquinoline alkaloids in plant extracts. The acaricide activity of the O. spixiana ethyl acetate extract can be correlated to the presence of alkaloids. K E Y W O R D S acaricide activity, alkaloids, HPTLC-DESI-MS n , Ocotea spixiana 1 | INTRODUCTION Ocotea is an expressive genus of the Lauraceae family, occurring mainly in tropical and subtropical areas. 1 Species of this genus are known for producing a variety of secondary metabolites, with neolignans, aporphine and benzylisoquinoline-type alkaloids as the most representative classes. 2,3 A wide range of biological activities from Ocotea species has been described in the literature, including

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The cattle tick Rhipicephalus microplus is an ectoparasite with high economic importance to bovine culture, mainly in tropical and subtropical regions. The resistance of the tick from the commercial acaricides has hindered its control, thus motivating the search for new strategies. The purpose of this study was to perform a critical review about the main molecular targets of R. microplus that are useful for the discovery of new acaricides. Bibliographic search was conducted in the databases PubMed, ScienceDirect and CAB Direct, using the following descriptors: ‘Rhipicephalus microplus’, ‘Boophilus microplus’, ‘molecular targets’ and ‘action’, published between 2010 and 2021. Out of the 212 publications identified, 17 articles were selected for study inclusion. This review described 14 molecular targets and among these 4 are targets from commercial acaricides. Most of them are enzymes to catalyse important reactions to tick survival, related to energetic metabolism, mechanisms of biotransformation and neurotransmission. The data will be helpful in the development of new more effective and selective acaricides.

The dual inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) is considered as an important strategy for the treatment of Alzheimer's disease. In this study, we applied the bioguided fractionations of Ocotea daphinifolia ethyl acetate active extract to furnish a fraction with high inhibitory activity for AChE and BuChE (82% and 92%, respectively). High‐performance liquid chromatography semipreparative purification of this fraction provided two new natural products: 1‐β‐D‐galactopyranosyl‐glycerol‐2,3‐heptanedionate, (1) whose complete chemical structural elucidation was made with spectrometric analysis (MS, 1D, and 2D NMR) and its minor derivative 1‐β‐D‐gulopyranosyl‐glycerol‐2,3‐heptanedionate; (2) which could be characterized by 2D 1H‐13C heteronuclear single‐quantum correlation spectra analysis. Investigation of the intermolecular interactions with cholinesterases was carried out by molecular docking studies, and results suggested that both compounds are capable to interact with the catalytic site of both enzymes. Compounds 1 and 2 interact with residues of catalytic domains and the peripheral anionic binding site of AChE and BuChE. The results are comparable to those achieved with rivastigmine and galantamine. Thus, this study provides evidence for consideration of the glycosylglycerol from O. daphnifolia as new valuable dual cholinesterases inhibitor.