UPLC-TQD-MS/MS Method Validation for Quality Control of Alkaloid Content in Lepidium meyenii (Maca)-Containing Food and Dietary Supplements.

Lepidium meyenii Walp. (Brassicaceae), also known as Maca or Peruvian ginseng, is a common ingredient in food supplements with many claimed health benefits, such as improved endurance, increased energy level, and enhanced sexual properties. Due to potential toxicity of its chemicals, including alkaloids, some regulatory authorities, e.g., in Belgium, Germany, the United States, expressed concerns about the safe consumption of Maca root. However, due to the lack of commercial standards, no established analytical method currently exists for this purpose. The current project focuses on the quantitative determination of potentially toxic alkaloids from Maca. The current study presents the first analytical method for quality control of alkaloid content in Maca-containing food and dietary supplements, assessing the presence of 11 major compounds belonging to three different classes, i.e., imidazole, ß-carboline, and pyrrole alkaloids. An accurate, rapid, and sensitive UPLC-TQD-MS/MS method is reported, which was fully validated according to the International Council for Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) and SANTE/11312/2021 guidelines. To ensure the method's applicability and practicability in the absence of primary standards, validation of secondary standards (SSs) alongside primary standards (PSs) was also conducted for imidazole alkaloids. As a result, in Maca raw powder, total alkaloid content was found to vary from 418 to 554 ppm (mg/kg). Furthermore, all quantified imidazole alkaloids were ascertained to be the major alkaloids with the total content from 323 to 470 ppm in Maca raw powder, followed by the ß-carboline and pyrrole alkaloids. It was also observed that the commercial preparation of finished products affects the total alkaloid content, evidenced by the large variation from 56 to 598 ppm. Ultimately, from a regulatory point of view, it seems advisible not to request the complete absence of the alkaloids but to impose a maximum level based on safety considerations. In addition to the analytical method, a low-cost, simple, and scalable synthetic scheme of macapyrrolins A, C, and G was reported for the first time.

Hepatoprotective effects of leaf extract of Annona senegalensis against aflatoxin B1 toxicity in rats.

Global aflatoxin contamination of agricultural commodities is of the most concern in food safety and quality. This study investigated the hepatoprotective effect of 80% methanolic leaf extract of Annona senegalensis against aflatoxin B1 (AFB1)-induced toxicity in rats. A. senegalensis has shown to inhibit genotoxicity of aflatoxin B1 in vitro. The rats were divided into six groups including untreated control, aflatoxin B1 only (negative control); curcumin (positive control; 10 mg/kg); and three groups receiving different doses (100 mg/kg, 200 mg/kg, and 300 mg/kg) of A. senegalensis extract. The rats received treatment (with the exception of untreated group) for 7 days prior to intoxication with aflatoxin B1. Serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, and creatinine were measured. Hepatic tissues were analysed for histological alterations. Administration of A. senegalensis extract demonstrated hepatoprotective effects against aflatoxin B1-induced toxicity in vivo by significantly reducing the level of serum aspartate aminotransferase and alanine aminotransferase and regenerating the hepatocytes. No significant changes were observed in the levels of alkaline phosphatase, lactate dehydrogenase, and creatinine for the AFB1 intoxicated group, curcumin+AFB1 and Annona senegalensis leaf extract (ASLE)+AFB1 (100 mg/kg, 200 mg/kg, and 300 mg/kg body weight [b.w.]) treated groups. Annona senegalensis is a good candidate for hepatoprotective agents and thus its use in traditional medicine may at least in part be justified.Contribution: The plant extract investigated in this study can be used in animal health to protect the organism from toxicity caused by mycotoxins.

A mini-review of the anti-SARS-CoV-2 potency of Amaryllidaceae alkaloids.

BACKGROUND: Nature has perennially served as an infinite reservoir of diverse chemicals with numerous applications benefiting humankind. In recent years, due to the emerging COVID-19 pandemic, there has been a surge in studies on repurposing natural products as anti-SARS-CoV-2 agents, including plant-derived substances. Among all types of natural products, alkaloids remain one of the most important groups with various known medicinal values. The current investigation focuses on Amaryllidaceae alkaloids (AAs) since AAs have drawn significant scientific attention as anti-SARS-CoV-2 agents over the past few years. PURPOSE AND STUDY DESIGN: This study serves as a mini-review, summarizing recent advances in studying the anti-SARS-CoV-2 potency of AAs, covering two aspects: structure-activity relationship and mechanism of action (MOA). METHODS: The study covers the period from 2019 to 2023. The information in this review were retrieved from common databases including Web of Science, ScienceDirect, PubMed and Google scholar. Reported anti-SARS-CoV-2 potency, cytotoxicity and possible biological targets of AAs were summarized and classified into different skeletal subclasses. Then, the structure-activity relationship (SAR) was explored, pinpointing the key pharmacophore-related structural moieties. To study the mechanism of action of anti-SARS-CoV-2 AAs, possible biological targets were discussed. RESULTS: In total, fourteen research articles about anti-SARS-CoV-2 was selected. From the SAR point of view, four skeletal subclasses of AAs (lycorine-, galanthamine-, crinine- and homolycorine-types) appear to be promising for further investigation as anti-SARS-CoV-2 agents despite experimental inconsistencies in determining in vitro half maximal inhibitory effective concentration (EC50). Narciclasine, haemanthamine- and montanine-type skeletons were cytotoxic and devoid of anti-SARS-CoV-2 activity. The lycorine-type scaffold was the most structurally diverse in this study and preliminary structure-activity relationships revealed the crucial role of ring C and substituents on rings A, C and D in its anti-SARS-CoV-2 activity. It also appears that two enantiomeric skeletons (haemanthamine- and crinine-types) displayed opposite activity/toxicity profiles regarding anti-SARS-CoV-2 activity. Pharmacophore-related moieties of the haemanthamine/crinine-type skeletons were the substituents on rings B, C and the dioxymethylene moiety. All galanthamine-type alkaloids in this study were devoid of cytotoxicity and it appears that varying substituents on rings C and D could enhance the anti-SARS-CoV-2 potency. Regarding MOAs, initial experimental results suggested Mpro and RdRp as possible viral targets. Dual functionality between anti-inflammatory activity on host cells and anti-SARS-CoV-2 activity on the SARS-CoV-2 virus of isoquinoline alkaloids, including AAs, were suggested as the possible MOAs to alleviate severe complications in COVID-19 patients. This dual functionality was proposed to be related to the p38 MAPK signaling pathway. CONCLUSION: Overall, Amaryllidaceae alkaloids appear to be promising for further investigation as anti-SARS-CoV-2 agents. The skeletal subclasses holding the premise for further investigation are lycorine-, crinine-, galanthamine- and homolycorine-types.

Phytochemical Profiling by UPLC-ESI-QTOF-MS of Kalaharia uncinata (Schinz) Moldenke, Widely Used in Traditional Medicine in DR Congo.

Kalaharia uncinata (Schinz) Moldenke, is a tropical erect bushy shrub or subshrub of the Lamiaceae family. It is an endemic plant species of Southern Africa, widely used in the pharmacopoeia against upper respiratory tract infections. A previously conducted ethnobotanical survey revealed that it is believed to contain bioactive substances. However, no relevant phytochemical information was available. This study aimed to perform a phytochemical characterization of K. uncinata and also to discuss the potential bioactivity of the identified phytochemical constituents based on documented data. Ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) was used for profiling and identification of the main phytochemical constituents from leaf extracts (MeOH 90 %, DCM, AcOEt, BuOH, hexane and residue) of K.uncinata. Twenty-four constituents, representing mainly flavonoids (14), followed by phenylethanoid glycosides (7), phenolic acids (2), and an iridoid glycoside (1) were tentatively identified. Most of the identified compounds are documented to have antiviral and anti-inflammatory properties, which could possibly be the rationale behind the use of K. uncinata against upper respiratory tract infections.

Phytochemical characterization and antifungal potential of leaf extracts of Mosiera bullata.

The investigation of natural alternatives to conventional fungicides is of imminent need. Mosiera bullata (Britton & P. Wilson) Bisse is a Cuban endemic plant species belonging to the Myrtaceae family. The objective of the present study was to perform a bioassay-guided fractionation to explore the potential of extracts and fractions from M. bullata leaves against a panel of fungal plant pathogens. The M. bullata total extract was confirmed to have good antifungal activity against R. oryzae (IC50 = 4.86 µg/mL) and moderate activity against F. oxysporum (IC50 = 352.40 µg/mL) and F. solani (IC50 = 427.38 µg/mL) and fungicidal effect against R. oryzae. Five compounds belonging to the class of phloroglucinol dimers were tentatively characterized by UHPLC-HRMS and reported for the first time in M. bullata and the genus Mosiera. These results suggest the potential of M. bullata total extract as a natural antifungal product for the control of diseases in agriculture.

HILIC UPLC/ QTof MS Method Development for the Quantification of AGEs Inhibitors - Trouble Shooting Protocol.

OBJECTIVE: The paper reports an attempt to develop and validate a HILIC UPLC/ QTof MS method for quantifying N-ε-carboxymethyl-L-lysine (CML) in vitro, testing N-ε-carboxy[D2]methyl-L-lysine (d2-CML), and N-ε-carboxy[4,4,5,5-D4]methyl-L-lysine (d4-CML) as internal standards. METHOD: During the method development, several challenging questions occurred that hindered the successful completion of the method. The study emphasizes the impact of issues, generally overlooked in the development of similar analytical protocols. For instance, the use of glassware and plasticware was critical for the accurate quantification of CML. Moreover, the origin of atypical variation in the response of the deuterated internal standards, though widely used in other experimental procedures, was investigated. RESULT: A narrative description of the systematic approach used to address the various drawbacks during the analytical method development and validation is presented. CONCLUSION: Reporting those findings can be considered beneficial while bringing an insightful notion about critical factors and potential interferences. Therefore, some conclusion and ideas can be drawn from these trouble-shooting questions, which might help other researchers to develop more reliable bioanalytical methods, or to raise their awareness of stumbling blocks along the way.

Anti-SARS-CoV-2 Activity and Cytotoxicity of Amaryllidaceae Alkaloids from Hymenocallis littoralis.

The Amaryllidaceae species are well-known as a rich source of bioactive compounds in nature. Although Hymenocallis littoralis has been studied for decades, its polar components were rarely explored. The current phytochemical investigation of Amaryllidaceae alkaloids from H. littoralis led to the identification of three previously undescribed compounds: O-demethyl-norlycoramine (1), (-)-2-epi-pseudolycorine (2) and (+)-2-epi-pseudolycorine (3), together with eight known compounds: 6α-hydroxyhippeastidine (4), 6ß-hydroxyhippeastidine (5), lycorine (6), 2-epi-lycorine (7), zephyranthine (8), ungeremine (9), pancratistatin (10) and 9-O-demethyl-7-O-methyllycorenine (11). Among the eight previously reported compounds, five were isolated from H. littoralis for the first time (compounds 4, 5, 7, 8, and 9). Compounds 1, 4, 5, 7, 8, and 11 exhibited weak anti-SARS-CoV-2 activity (EC50 = 40-77 µM) at non-cytotoxic concentrations. Assessment of cytotoxicity on the Vero-E6 cell line revealed lycorine and pancratistatin as cytotoxic substances with CC50 values of 1.2 µM and 0.13 µM, respectively. The preliminary structure-activity relationship for the lycorine-type alkaloids in this study was further investigated, and as a result ring C appears to play a crucial role in their anti-SARS-CoV-2 activity.

In Vitro Biotransformation and Anti-Inflammatory Activity of Constituents and Metabolites of Filipendula ulmaria.

(1) Background: Filipendula ulmaria (L.) Maxim. (Rosaceae) (meadowsweet) is widely used in phytotherapy against inflammatory diseases. However, its active constituents are not exactly known. Moreover, it contains many constituents, such as flavonoid glycosides, which are not absorbed, but metabolized in the colon by gut microbiota, producing potentially active metabolites that can be absorbed. The aim of this study was to characterize the active constituents or metabolites. (2) Methods: A F. ulmaria extract was processed in an in vitro gastrointestinal biotransformation model, and the metabolites were characterized using UHPLC-ESI-QTOF-MS analysis. In vitro anti-inflammatory activity was evaluated by testing the inhibition of NF-κB activation, COX-1 and COX-2 enzyme inhibition. (3) Results: The simulation of gastrointestinal biotransformation showed a decrease in the relative abundance of glycosylated flavonoids such as rutin, spiraeoside and isoquercitrin in the colon compartment, and an increase in aglycons such as quercetin, apigenin, naringenin and kaempferol. The genuine as well as the metabolized extract showed a better inhibition of the COX-1 enzyme as compared to COX-2. A mix of aglycons present after biotransformation showed a significant inhibition of COX-1. (4) Conclusions: The anti-inflammatory activity of F. ulmaria may be explained by an additive or synergistic effect of genuine constituents and metabolites.

Pharmacognostic Study, Diuretic Activity and Acute Oral Toxicity of the Leaves of Xiphidium caeruleum Aubl. Collected in Two Different Phenological Stages.

Xiphidium caeruleum Aubl. is traditionally used in Cuba as an analgesic, anti-inflammatory, antilithiatic and diuretic remedy. Here we studied the pharmacognostic parameters of the leaves of X. caeruleum, the preliminary phytochemical composition, diuretic activity and acute oral toxicity of the aqueous extracts from the leaves of plants collected in the vegetative (VE) and flowering (FE) stages. The morphological characteristics and physicochemical parameters of leaves and extracts were determined. The phytochemical composition was assessed by phytochemical screening, TLC, UV, IR and HPLC/DAD profiles. The diuretic activity was evaluated in Wistar rats and compared to furosemide, hydrochlorothiazide and spironolactone. Epidermal cells, stomata and crystals were observed on the leaf surface. Phenolic compounds were identified as the main metabolites, including phenolic acids (gallic, caffeic, ferulic and cinnamic acids) and flavonoids (catechin, kaempferol-3-O-glucoside and quercetin). VE and FE showed diuretic activity. The activity of VE was similar to furosemide, and the activity of FE resembled spironolactone. No acute oral toxicity was observed. The presence of flavonoids and phenols in VE and FE may explain at least in part the traditional use and provide some insight into the reported ethnomedical use as a diuretic. Because of the differences in polyphenol profiles between VE and FE, further studies should be carried out to standardize the harvesting and extraction conditions in order to use X. caeruleum leaf extract as herbal medicine.

Saponin and Fatty Acid Profiling of the Sea Cucumber Holothuria atra, α-Glucosidase Inhibitory Activity and the Identification of a Novel Triterpene Glycoside.

Saponin-rich sea cucumber extracts have shown antidiabetic effects in a few reports. Although the triterpene glycosides of sea cucumbers are commonly isolated from their Cuvierian tubules, these are absent in Holothuria atra Jaeger. Therefore, this study intended to investigate the saponin profile in the body wall of H. atra, as well as to assess the α-glucosidase inhibitory activity of the H. atra extracts. The chemical profiling of sea cucumber extracts was conducted by UPLC-HRMS analysis. This resulted in the tentative identification of 11 compounds, 7 of which have not been reported in the H. Atra body wall before. Additionally, two triterpene glycosides were purified and their structures were elucidated based on HRMS and NMR data: desholothurin B (1), and a novel epimer, 12-epi-desholothurin B (2). Moreover, the fatty acid profile of the H. atra body wall was investigated by GC-MS. It was found that the Me90 fraction of the H. atra body wall showed the strongest α-glucosidase inhibitory activity (IC50 value 0.158 ± 0.002 mg/mL), thus making it more potent than acarbose (IC50 value 2.340 ± 0.044 mg/mL).

An in-depth multiphasic analysis of the chocolate production chain, from bean to bar, demonstrates the superiority of Saccharomyces cerevisiae over Hanseniaspora opuntiae as functional starter culture during cocoa fermentation.

Hanseniaspora opuntiae is a commonly found yeast species in naturally fermenting cocoa pulp-bean mass, which needed in-depth investigation. The present study aimed at examining effects of the cocoa isolate H. opuntiae IMDO 040108 as part of three different starter culture mixtures compared with spontaneous fermentation, regarding microbial community, substrate consumption, and metabolite production dynamics, including volatile organic compound (VOC) and phytochemical compositions, as well as compositions of the cocoa beans after fermentation, cocoa liquors, and chocolates. The inoculated H. opuntiae strain was unable to prevail over background yeasts present in the fermenting cocoa pulp-bean mass. It led to under-fermented cocoa beans after four days of fermentation, which was however reflected in higher levels of polyphenols. Cocoa fermentation processes inoculated with a Saccharomyces cerevisiae strain enhanced flavour production during the fermentation and drying steps, which was reflected in richer and more reproducible aroma profiles of the cocoa liquors and chocolates. Sensory analysis of the cocoa liquors and chocolates further demonstrated that S. cerevisiae led to more acidic notes compared to spontaneous fermentation, as a result of an advanced fermentation degree. Finally, different VOC profiles were found in the cocoa beans throughout the whole chocolate production chain, depending on the fermentation process.

Evaluation of Major Constituents of Medicinally Important Plants for Anti-Inflammatory, Antidiabetic and AGEs Inhibiting Properties: In Vitro and Simulatory Evidence.

Diabetes mellitus (DM) is a global health concern that is associated with several micro- and macrovascular complications. We evaluated several important medicinal plant constituents, including polyphenols and flavonoids, for α-glucosidase inhibition, AGEs' inhibitory activities using oxidative and no-oxidative assays, the inhibition of protein cross link formation, 15-lipoxydenase inhibition and molecular docking. The molecular docking studies showed high binding energies of flavonoids for transcriptional regulars 1IK3, 3TOP and 4F5S. In the α-glucosidase inhibition assay, a significant inhibition was noted for quercitrin (IC50 7.6 µg/mL) and gallic acid (IC50 8.2 µg/mL). In the AGEs inhibition assays, quercetin showed significant results in both non-oxidative and (IC50 0.04 mg/mL) and oxidative assays (IC50 0.051 mg/mL). Furthermore, quercitrin showed inhibitory activity in the non-oxidative (IC50 0.05 mg/mL) and oxidative assays (IC50 0.34 mg/mL). A significant inhibition of protein cross link formation was observed by SDS-PAGE analysis. Quercitrin (65%) and quercetin (62%) showed significant inhibition of 15-lipoxygenase. It was thus concluded that flavonoids and other polyphenols present in plant extracts can be effective in management of diabetes and allied co-morbidities.

Inhibitory Effect on Nitric Oxide Release in LPS-Stimulated Macrophages and Free Radical Scavenging Activity of Croton linearis Jacq. Leaves.

Oxidative stress is an important component of many diseases including cancer, along with inflammatory and neurodegenerative processes. Natural antioxidants have emerged as promising substances to protect the human body against reactive oxygen and nitrogen species. The present study evaluates the inhibition of nitric oxide (NO) production in LPS-stimulated RAW 264.7 murine macrophages and the free radical scavenging activity of Croton linearis Jacq. leaves. UPLC-QTOF-MS analysis identified 18 compounds: nine alkaloids with a morphinane, benzylisoquinoline or aporphine nucleus, and nine O-glycosylated-flavonoids with quercetin, kaempferol and isorhamnetin as the aglycones. The crude extract (IC50 21.59 µg/mL) and the n-hexane fraction (IC50 4.88 µg/mL) significantly reduced the NO production in LPS-stimulated macrophages but with relatively high cytotoxicity (CC50 75.30 and CC50 70.12 µg/mL, respectively), while the ethyl acetate fraction also showed good activity (IC50 40.03 µg/mL) without affecting the RAW 264.7 cell viability. On the other hand, the crude extract, as well as the dichloromethane and ethyl acetate fractions, showed better DPPH and ABTS free radical scavenging activities. Considering the chemical composition and the activity observed for Croton linearis leaves, they may be considered a good source of antioxidants to combat oxidative damage-related diseases.

Isocyanates may contribute to allergic contact dermatitis from diabetes devices and wound dressings.

BACKGROUND: Isocyanates are well-known occupational allergens, but can also be present in medical devices. OBJECTIVES: To highlight that contact sensitization to isocyanates might contribute to allergic contact dermatitis (ACD) from polyurethane (PU)-containing diabetes devices and wound dressings. PATIENTS AND METHODS: Nineteen patients with suspected ACD from diabetes devices and/or wound dressings were patch tested to an isocyanate series. Four wound dressings, six diabetes devices and four monomeric isocyanate patch test preparations were analysed with gas chromatography - mass spectrometry. RESULTS: Eight patients reacted to isocyanates and corresponding amines: 3 to isophorone diisocyanate (IPDI), 4 to 4,4'-diaminodiphenylmethane (MDA), 4 to 2,4-toluene diisocyanate (TDI) and 1 to polymeric methylene diphenyl diisocyanate (PMDI). Three of four wound dressings contained isocyanates (methylene diphenyl diisocyanate [MDI], TDI and/or IPDI), whereas five of six diabetes devices contained 4,4'-MDI, and one of them also IPDI. None of the medical devices contained 1,6-hexamethylene diisocyanate. Contrary to IPDI, and especially MDI, only the concentration of the TDI patch test preparation corresponded approximately (80%) to its label. CONCLUSION: Patch tests with isocyanates may be worth-while in patients with suspected ACD from PU-containing medical devices. Besides MDA, and PMDI, also TDI might potentially be a marker for MDI-sensitization.

Availability and Metabolic Fate of Olive Phenolic Alcohols Hydroxytyrosol and Tyrosol in the Human GI Tract Simulated by the In Vitro GIDM-Colon Model.

Hydroxytyrosol (HTyr) and tyrosol (Tyr) are the most well studied phenolic alcohols of olive oil and olive products demonstrating numerous and significant beneficial health effects. However, their activity in the human organism as food bioactives is strongly associated with their bioavailability and metabolism, while manifested through their metabolites. Nevertheless, there are limited studies investigating their biotransformation and mainly catabolism by gut microflora under a holistic interpretation close to the human organism. Thus, in the present study, the GastroIntestinal Dialysis (GIDM)-colon model, a continuous flow in vitro dialysis system mimicking physiological conditions during human gastrointestinal digestion, was used to explore the metabolism of HTyr and Tyr as pure compounds. The GIDM-colon model simulates absorption from the lumen to the mucosa, followed by the colon phase using pooled human fecal suspensions. Samples were collected at different time points and analyzed via LC-Orbitrap MS. An integrated approach combining Multivariate Data Analysis (MVA) and thorough dereplication procedures led to the identification of HTyr and Tyr metabolites in different phases (gastric, small intestine, and colon), yielding also valuable information about metabolites kinetics. To our knowledge, this is the first study reporting full spectrometric data of HTyr and Tyr metabolites along with possible transformation mechanisms in the GI tract.

Protective effects of methanolic leaf extracts of Monanthotaxis caffra against aflatoxin B1-induced hepatotoxicity in rats.

Aflatoxins are potent hepatotoxic and carcinogenic secondary metabolites produced by toxigenic fungi. The present study investigated the protective effect of methanolic leaf extracts of Monanthotaxis caffra (MLEMC) against aflatoxin B1-induced toxicity in male Sprague-Dawley rats. The rats were randomly divided into 6 groups of 8 animals each. Five groups were administered orally for seven days with three different concentrations of MLEMC (100 mg/kg, 200 mg/kg and 300 mg/kg), curcumin (10 mg/kg) or vehicle (25% propylene glycol). The following day, these groups were administered 1 mg/kg b.w. of aflatoxin B1 (AFB1). The experiment was terminated three days after administration of AFB1. Group 6 represented untreated healthy control. Serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatinine and liver histopathology were evaluated. Methanolic leaf extracts of M. caffra decreased the levels of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and creatinine in the sera of rats as compared with the AFB1 intoxicated group. Co-administration of MLEMC improved the histological characteristics of the hepatocytes in contrast to the AFB1 treated group, which had mild to severe hepatocellular injuries including bile duct proliferation, bile duct hyperplasia, lymphoplasmacytic infiltrate and fibrosis. Extracts of M. caffra were beneficial in mitigating the hepatotoxic effects of AFB1 in rats by reducing the levels of liver enzymes and preventing hepatic injury.

Antiplasmodial activity of alkaloids from Croton linearis leaves.

Croton linearis is a shrub that grows in Caribbean regions, which is rich in metabolites such as alkaloids. The main aim of this study was to evaluate the antiplasmodial effect of alkaloids from this species. Three isoquinoline alkaloids, i.e. reticuline (1), laudanidine (2) and 8,14-dihydrosalutaridine (3), were isolated from the leaves of C. linearis by flash chromatography and semi-preparative HPLC-DAD-MS. Their structures were elucidated by spectroscopic techniques. Antiplasmodial activity against the chloroquine-resistant strain Plasmodium falciparum K1 and cytotoxicity against MRC-5 cells (human fetal lung fibroblast cells) were assessed in vitro. Reticuline, laudanidine and 8,14-dihydrosalutaridine showed moderate antiplasmodial activity with IC50 values of 46.8 ± 0.6, 17.7 ± 0.6 and 16.0 ± 0.5 µM, respectively, but no cytotoxicity was observed in a concentration up to 64.0 µM. This is the first report on the antiplasmodial activity of laudanidine and 8,14-dihydrosalutaridine.

The effect of cocoa alkalization on the non-volatile and volatile mood-enhancing compounds.

Alkalization is a process to improve color, dispersibility and flavor of cocoa powder but is likely to have a negative effect on the phytochemicals. Hereto, the impact of alkalization degree (none, medium and high) on the potential mood-enhancing compounds corresponding to the four levels of the mood pyramid model (flavanols, methylxanthines, biogenic amines and orosensory properties) was investigated. The phytochemical content, analyzed via UPLC-HRMS, showed reduction of specific potential mood-enhancing compounds upon alkalization, implying a decrease in bitterness and astringency. Moreover, volatile compounds analysis via HS-SPME-GC-MS indicated that alkalization reduced the levels of volatile compounds, responsible for acidity, fruity, floral and cocoa aromas. With respect to the orosensory properties, the cocoa powder palatability was suggested to be increased due to reduced acidity, bitterness, and astringency, while the desired volatile compounds were reduced. However, sensorial analysis is required to link the volatile results with the overall effect on the flavor perception.

LC-MS Characterization and Biological Activities of Cuban Cultivars of Plectranthus neochilus Schltr.

Plectranthus neochilus Schltr. (Lamiaceae) is a plant recently introduced in Cuba. Worldwide, it is an ethnomedicinal alternative for its use against microbial infections, but the Cuban population use the extracts to treat sleep disorders. To address this apparent incongruity, four collections (from different seasonal conditions in the year) of Cuban P. neochilus cultivars were analyzed in terms of their pharmacognostic characteristics. Three extracts using fresh and dried leaves were chemically and biologically characterized. UPLC-DAD-MS/MS analysis was performed to determine their chemical composition, while a panel of nine microorganisms was used to evaluate their antimicrobial activity. Finally, cytotoxic effects of different fractions were measured in three cell lines by the resazurin viability assay. In contrast to previously reported micro and macromorphological properties of P. neochilus, the leaves from the Cuban cultivars did not present glandular trichomes, nor did they produce quantifiable levels of essential oils. Moreover, aqueous extracts used by the population revealed no significant antimicrobial activity and were not cytotoxic. The three extracts showed a similar phytochemical composition, i.e., eight flavonoids, seven abietane diterpenes, and rosmarinic acid as the major constituent, most of them reported for the first time in this species. The low yield of essential oil, the absence of glandular trichomes, compounds with a high level of oxidation, and a moderate antimicrobial activity detected were the most distinctive pharmacognostic and biological characteristics of P. neochilus grown in Cuba. These aspects could explain its non-use as an antimicrobial.

Novel flavonol-3-O-methylethers from Zanthoxylum pistaciifolium Griseb. (Rutaceae).

Zanthoxylum pistaciifolium Griseb. is a tree endemic to Cuba, occasionally used in herbal medicine. Previously, the antitrypanosomal activity of a n-hexane-2-butanone extract of Z. pistaciifolium leaves and of its constituent skimmianine were published. In the current study a more thorough examination of the respective extract is performed, which led to the isolation and identification of three flavonoids, more specifically, the flavonol-3-O-methylethers kaempferol-3-O-methylether (1) and novel compounds kaempferol-3-O-methylether-5-O-ß-D-glucoside (2) and kaempferol-8-hydroxy-3,7-O-dimethylether-5-O-ß-D-glucoside (3). All compounds were screened for their antimicrobial and antiprotozoal activity and cytotoxicity towards MRC-5 SV2 cells. Compound 1 showed a moderate to weak activity against Trypanosoma cruzi (IC50 30.8 µM), T. brucei (IC50 15.4 µM) and Plasmodium falciparum (IC50 53.8 µM), but also showed cytotoxicity (CC50 19.0 µM). Compounds 2 and 3 did not display activity in any of the assays (IC50 and CC50 > 64 µM).[Formula: see text].