Exploring the Chemistry of Ocimum Species under Specific Extractions and Chromatographic Methods: A Systematic Review

Ocimum is considered the largest genus in the Lamiacea family. The genus includes basil, a group of aromatic plants with a wide range of culinary uses that nowadays draws attention for its medicinal and pharmaceutical potential. This systematic review intends to explore the chemical composition of nonessential oils and their variation across different Ocimum species. Moreover, we aimed to identify the state of knowledge regarding the molecular space in this genus as well as the different methods of extraction/identification and geographical location. Seventy-nine eligible articles were selected for the final analysis, from which we extracted more than 300 molecules. We found that the countries with the highest number of studies into Ocimum species are India, Nigeria, Brazil, and Egypt. However, from all known species of Ocimum, only 12 were found to have an extensive chemical characterization, particularly Ocimum basilicum and Ocimum tenuiflorum. Our study focused especially on alcoholic, hydroalcoholic, and water extracts, in which the main techniques for compound identifications are GC-MS, LC-MS, and LC-UV. Across the compiled molecules, we found a wide variety of compounds, especially flavonoids, phenolic acids, and terpenoids, suggesting that this genus could be a very useful source of possible bioactive compounds. The information collected in this review also emphasizes the huge gap between the vast number of Ocimum species discovered and the number of studies in each of them that determined the chemical characterization.We thank the Universidad de Las Américas, Quito, Ecuador, for the financial support of the PhD students A. Beltrán-Noboa and M. Guevara-Terán. We also want to thank Universidad de Las Américas for supporting A. Jordan-Álvarez and E. Tejera and Y. Castillo, and Universidad San Francisco de Quito, Ecuador, for supporting J.M. Alvarez-Suarez

1H–NMR fingerprinting and supervised pattern recognition to evaluate the stability of virgin olive oil during storage

Metabolomic fingerprinting of virgin olive oil (VOO) by 1H NMR spectroscopy was used to study its stability during storage simulating normal shelf life conditions during its commercialization. A representative set of VOOs covering the full range of possible chemical compositions were exposed to light (500 lux for 12 h/day) at 25 °C for 12 months or stored in the dark at 25 °C, 30 °C and 35 °C for 24 months. Multivariate data analysis of the 1H NMR spectra of the oil samples provided classification models to evaluate VOO freshness and to verify the light exposure of the VOO during storage, as well as regression models to determine VOO storage time and tentatively the best before date of a fresh VOO. These predictive models disclosed the chemical compounds responsible for the compositional changes in VOO due to hydrolytic and oxidative degradation taking place during its storage, and confirmed that light and increasing temperature enhance these processes. The presence of characteristic resonances of hydroperoxides (primary oxidation products) and the decrease of 1H signals assigned to phenolic compounds, mainly secoiridoid derivatives, and other minor compounds such as fatty acids, squalene and native (E)-2-hexenal present in fresh VOO revealed its oxidative degradation. Further, the emergence of low intensity 1H signals of saturated aldehydes meant that the secondary oxidation process has started at a low rate and yield. Moreover, the decrease of the 1H signals of triacylglycerides and sn-1,2-diacylglycerides, and the increase of sn-1,3-diacylglycerides indicated that hydrolytic degradation of VOO and diacylglyceride isomerisation was occurring. 1H NMR fingerprint of VOO together with pattern recognition techniques afford relevant information to assess the quality of VOOs taking into consideration legal, sensory and health-promoting aspects.This work was supported by the European Commission within the Horizon 2020 Programme [grant agreement No. 635690, 2014–2020], and developed in the framework of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale”. The information contained in this article reflects the authors’views; the European Commission is not liable for any use of the information contained herein

One-Step Isolation of Monoterpene Indole Alkaloids from Psychotria Leiocarpa Leaves and Their Antiviral Activity on Dengue Virus Type-2

The leaf MeOH extract of Psychotria leiocarpa (Rubiaceae) showed in vitro non-cytotoxic and anti-dengue virus serotype 2 (DENV2) activity in human hepatocarcinoma cell lineage (HepG2). A one-step and cost-effective reversed-phase solid-phase extraction method based on high-performance liquid chromatography (HPLC) parameters allowed the isolation, directly from this bioactive extract, of the monoterpene indole alkaloids: N-glucopyranosyl vincosamide (1), vincosamide (2) and strictosidinic acid (3). The chemical structures were characterized based on 1D and 2D nuclear magnetic resonance (NMR), UV and high-resolution mass spectra (HRMS). The methodology has also allowed yielding a polyphenolic-rich fraction that was analyzed by high-performance liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) revealing two fiavonol triglycosides (4, 5) and three caffeoylquinic acid isomers (6-8). Compound 3 is reported for the first time in P leiocarpa and all the phenolic compounds (4-8) are described for the first time in the genus Psychotria. Compounds 1-3 showed to be non-cytotoxic and anti-dengue active towards DENV2, highlighting vincosamide (2).This work was supported by Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), processes No. E-26/111.373/2014 and E-26/203.225/2017. DGL and JOC thank Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), finance code 001, for their fellowships. TW thanks both CAPES and FAPERJ for his fellowships. The authors thank the NMR Lab of the Instituto de Pesquisas em Produtos Naturais, Universidade Federal do Rio de Janeiro for the NMR spectra and MSc Matheus Oliveira, Dr Marcelo M. Pereira and Dr Denise Freire for their support. Technical and staff support provided by SGIker (UPV/EHU, MICINN, GV/EJ, ESF) is also gratefully acknowledged

Comprehensive characterisation of polyphenols in leaves and stems of three anti‐dengue virus type‐2 active Brazilian Faramea

A comprehensive characterization of polyphenols by online high-performance liquid chromatography with diode array detection coupled to electrospray ionization and triple quadrupole mass spectrometry (HPLC-DAD-ESI-CID-MS/MS) of leaf and stem MeOH extracts from the Brazilian species Faramea bahiensis, F. hyacinthina and F. truncata (Rubiaceae) was performed. Structures have been assigned on the basis of the complementary information obtained from retention time, UV-visible spectra, scan mode MS spectra, and fragmentation patterns in product ion scan MS/MS spectra in different collision energies. The use of the mechanisms and fragmentation patterns established with phenolic standards led to successfully characterize thirty-one phenolic compounds. Flavanone O-mono- and diglycosides, flavonol O-mono- and diglycosides, flavone O-mono-, di- and tri-glycosides and flavone C-mono- and diglycosides were identified. Scopoletin, caffeic acid and syringic acid were also detected. The leaves of F. bahiensis showed to be the richest in phenolic compounds while the leaves of the other two species presented lower diversity and quantity, especially F. truncata. The stems revealed that in general have lower occurrence of these compounds than the leaves. The assay for in vitro cytotoxity and DENV serotype 2 (DENV-2) infected hepatocarcinoma cell lineage (HepG2) of the stem extracts showed that F. hyacinthina and F. bahiensis presented a similar anti-DENV-2 activity to those previously described to their leaves. However, a loss of cytoprotective activity of F. bahiensis and a higher cytotoxicity of F. truncata relative to those previously described to their leaves was observed.Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ-Brazil) (Proc. No E-26/111.373/2014