Exploring Cassia mimosoïdes as a promising natural source of steroids with potent anti-cancer, urease inhibition, and antimicrobial properties.

The genus Cassia is a rich source of physiologically active secondary metabolites, including a novel compound named 21-methylene-24-ethylidene lophenol, alongside 15 known compounds. These compounds were characterized using different spectroscopic techniques. They exhibited promising antimicrobial activity, particularly against bacteria causing gastrointestinal infections. Compound 1 showed strong anti-bacterial activity against H. pylori and S. aur with MIC values of 0.28 and 0.12 µg mL-1 respectively. The study investigated their impact on H. pylori, a contributor to ulcer development, by inhibiting the urease enzyme. Inhibiting urease can reduce H. pylori's pathogenic potential, evident from the fact that the compounds evaluated toward urease enzyme showed higher inhibitory activity (1.024 ± 0.43 6.678±0.11 µM) compared to standard thiourea (IC50 = 18.61 ± 0.11 µM). Molecular docking studies confirmed their inhibitory action, with compound 7 notably outperforming thiourea in inhibiting urease (-6.95 kcal mol-1vs. -3.13 kcal mol-1). Additionally, these compounds showed positive effects on liver functioning, which H. pylori can impair. Compound 9 shows the best response against human HepG2 liver cancer cell lines i.e., % viability is 14.47% ± 0.69 and IC50 is 7.8 µM ± 0.21. These compounds hold potential as lead compounds for addressing gastrointestinal and liver disorders caused by H. pylori.

Pyrroloquinolones B-F: Five unusual alkaloids from Vernonia glabra (Steetz) Vatke (Asteraceae).

Five unusual alkaloids featuring a pyrrolo[1,2-a]quinolone skeleton (pyrroloquinolones B-F, 1-5) were isolated from the ethanol extract of the whole plant of Vernonia glabra (Steetz) Vatke, along with sixteen known compounds. Their structures were established by means of spectroscopic (1D and 2D NMR, UV, IR, and ECD) and high resolution mass spectrometric techniques as well as by comparison of their spectroscopic data with those reported in the literature. The ethanol extract and some isolated compounds were assessed for their antibacterial activity against four bacterial strains. The extract was significantly active against Staphylococcus aureus ATCC1026 and S. epidermidis ATCC35984 (MIC = 64 µg/mL). All the tested compounds showed moderate activity against S. epidermidis (16 ≤ MIC ≤ 64 µg/mL). Furthermore, this is the first report on tricyclic pyrrolo[1,2-a]quinolone alkaloids from a plant source. A biosynthetic pathway for the formation of these compounds is also proposed.

A new phenolic glycoside from the leaves of Flacourtia flavescens Willd.

Chemical study of the methanol extract from the leaves of Flacourtia flavescens led to the isolation of a new phenolic glucoside (1) along with fifteen known secondary metabolites namely shanzhiside methyl ester (2), aurantiamide acetate (3), caffeic acid methyl ester (4), caffeic acid (5), apigenin (6), luteolin (7), kaempferol (8), quercetin (9), gyrophoric acid (10), luteolin-7-O-ß-D-glucopyranoside (11), luteolin-4'-O-ß-D-glucopyranoside (12), kaempferol-7-O-α-L-rhamnopyranoside (13), kaempferol-3-O-ß-D-glucopyranosyl-(1→6)-O-α-L-rhamnopyranoside (14), kaempferol-3,7-O-α-L-dirhamnopyranoside (15) and (2S,3S,4R,8E)-2-((2'R)-2'-hydroxy-octadecanoylamino)-lignocerane-1,3,4-triol-8-ene (16). Their structures were elucidated by 1D and 2D NMR analysis and mass spectrometry. The extracts and the isolated compounds were evaluated for their antibacterial activities. The EtOAc extract was highly active (MIC = 32 and 64 µg/mL) against E. coli and E. faecalis, respectively. Compounds 1, 2, 2b, 5, 8, 9, and 12 (MIC = 16-32 µg/mL) were moderately active against some tested bacteria.

Structure elucidation of olasubscorpioside C, a new rotameric biflavonoid glycoside from the stem barks of Olax subscorpioidea (Oliv).

From the n-butanol soluble fraction of the ethanol extract of the medicinal plant Olax subscorpioidea, a previously unreported rotameric biflavonoid glycoside constituted of 4'-O-methylgallocatechin-(4α → 8)-4'-O-methylgallocatechin as aglycone named olasubscorpioside C (1) along with the known 4'-O-methylgallocatechin (2) were isolated. Their structures were determined on the basis of spectrometric and spectroscopic techniques including HRFABMS, 1 H and 13 C NMR, DEPT 135o , HSQC, HMBC, ROESY, and CD followed by comparison with the reported data.

Desmoarylcoumarin and episoyasapogenol B: two new compounds from Desmodium salicifolium (Poir.) DC (Fabaceae).

A new 3-arylcoumarin, 7-hydroxy-6-(1,1-dimethylallyl)-2',5'-dihydroxy-4'-(3,3dimethylprenyl)-3-arylcoumarin (desmoarylcoumarin) 1, a previously unreported oleanane-type triterpenoid, 3ß,22ß,23-trihydroxyolean-12-en (episoyasapogenol B) 2, together with five known flavonoids including darbergioidin (3), isoferreirin (4), quercetin (5), vitexin (6), swertizin (7), and one carbohydrate, sucrose (8) were isolated from the methanolic extract of the roots of Desmodium salicifolium. Their structures were elucidated mainly by extensive spectroscopic analysis (1D and 2D) and mass spectrometric (HRFAB-MS) data. The methanolic extract, EtOAc and n-BuOH fractions as well as some isolated compounds were assessed for their antibacterial and antioxidant activities. The EtOAc fraction exhibited moderate activity against Enterococcus faecalis with MIC value of 128 µg/mL. The methanolic extract and the EtOAc fraction displayed DPPH scavenging activity with EC50 values of 5.99 and 2.06 µg/mL, respectively. Compound 1 showed a moderate antibacterial activity against Enterococcus faecalis with a MIC of 16 µg/mL. It also showed moderate DPPH scavenging activity.

Mimonoside D: a new triterpenoid saponin from Mimosa diplotricha Sauvalle (Fabaceae).

A new triterpenoid saponin (Mimonoside D: 3-O-α-L-arabinopyranosyl-3ß-hydroxyolean-12-en-28-oic acid 28-O-ß-D-xylopyranosyl-(1→2)-ß-D- glucopyranoside ester (1)) was isolated from the aerial parts of Mimosa diplotricha Sauvalle together with nine known compounds: 7,4'-dihydroxyflavone (2), kaempferol (3), lupeol (4), betulinic acid (5), ß-sitosterol (6), ß-sitosterol-3-O-ß-D-glucopyranoside (7), lutein (8), 5,2'-dihydroxy-7,4',5'-trimethoxyflavone (9) and vitexin (10). Their structures were elucidated on the basis of spectroscopic (1 D and 2 D nuclear magnetic resonance) and high-resolution mass spectrometric data as well as by comparison of their spectral data with those of related compounds. Compounds 2, 7 and 8 had already been isolated from M. diplotricha, while compounds 3, 4, 5 and 6 have been isolated from other Mimosa species. Compound 2 moderately inhibited Proteus mirabilis (MIC = 32 µg/mL), weakly inhibited Pseudomonas aeruginosa (MIC = 64 µg/mL) and very weakly inhibited Staphylococcus aureus (MIC = 128 µg/mL) and Enterococus faecalis (MIC = 128 µg/mL).

Siamoside A: a new C-glycosylated flavone from Senna siamea (Lam.) H. S. Irwin & Barneby (Caesalpiniaceae).

Phytochemical investigation of the methanol extracts from the leaves and bark of Senna siamea resulted in the isolation of one new flavone C-glycoside: apigenin-8-C-[6''-(E)-feruloyl]-ß-D-glucopyranoside] (1), together with sixteen known compounds including quercetin-3-O-α-L-rhamnoside (2), vitexin (3), isovitexin (4), quercetin-3-O-ß-D-glucopyranoside (5), quercetin-3-O-ß-D-arabinopyranoside (6), quercetin (7), kaempferol (8), methyl inositol (9), sucrose (10), betulinic acid (11), vanillic acid (12), stigmastane-3ß,6α-diol (13), aurantiamide acetate (14), robinetinidol (15), catechin (16) and epicatechin (17). The structures of these compounds were established on the basis of their spectroscopic (1 D and 2 D NMR) and mass spectrometric (ESI-TOF-MS) data. The methanol extracts, fractions and some of the isolated compounds were screened for their antimicrobial properties against five microbial strains. The methanol extract and the ethyl acetate fraction from the bark showed very weak antifungal activity against C. glabrata with the same MIC value of 128 µg/mL. Compound 7 was weakly active against C. albicans with MIC of 32 µg/mL.

New bioactive flavonoid glycosides with antioxidant activity from the stem bark of Olax subscorpioidea Oliv.

A previously unreported gallocatechin glycoside, (2 R,3S) 4'-O-methyl-gallocatechin-3-O-α-ʟ-rhamnopyranoside (1) and an unseparable mixture of two previously undescribed dihydromyricetin glycosides, (2 R,3R) 4'-O-methyl-dihydromyricetin-3-O-α-ʟ-rhamnopyranoside (2a) and (2 R,3S) 4'-O-methyl-dihydromyricetin-3-O-α-ʟ-rhamnopyranoside (2 b) along with three known compounds were isolated from the n-butanol soluble fraction of the stem bark of Olax subscorpioidea Oliv. Their structures were elucidated by detailed spectroscopic analyses, including 1H NMR, 13C NMR, 1H-1H COSY, HSQC, HMBC, NOESY, HR-ESI-MS and chemical methods. The crude ethanol extract, the fractions, and some of the isolated compounds were screened for their antioxidant and antibacterial activities. They showed significant antioxidant activities with EC50 ranging from 6.29 to 18.19 µg/mL in 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and EC50 ranging from 85.77 to 86.39 mmol FeSO4/g in ferric reducing antioxidant power (FRAP) methods compared with 2.29 µg/mL and 3.52 mmol FeSO4/g for the positive control (ʟ-ascorbic acid). Nevertheless, no inhibition was observed against the tested bacterial strains at a MIC less than 256 µg/mL.

Bioactive Arylnaphthalide Lignans from Justicia depauperata.

Eleven previously undescribed arylnaphthalide lignans (1-11) together with seven known compounds were isolated from the whole plant of Justicia depauperata. The structures of 1-11 were elucidated by spectroscopic analysis and mass spectrometry. Compounds 6 (IC50 = 4.1 µM) and 9 (IC50 = 9.5 µM) displayed cytotoxic activity against the KB-3-1 cervical carcinoma cell line. This report provides an insight into the conformational equilibria occurring in the arylnaphthalide lignan constituents of this plant.

Echinocystic Acid Bidesmoside Saponins from Microglossa afzelii O. Hoffm and Their Cytotoxic Activity against the CAL-27 Oral Squamous Carcinoma Cell Line.

This paper describes eight new triterpenoid saponins, including afzeliioside A (1), four acetylated afzeliiosides as pairs of inseparable regioisomers, called afzeliiosides B/C (2/3) and D/E (4/5), afzeliiosides F-H (6-8), and a known impatiprin C (9), which were isolated from the n-BuOH fraction of the liana of Microglossa afzelii. Their structures were established mainly by extensive spectroscopic analysis, including 1D and 2D NMR, HRFAB-MS, tandem ESI-MS/MS, and chemical methods, as well as a comparison of their spectral data with those of related compounds. All the isolates were screened for their cytotoxic activity against the CAL-27 oral squamous carcinoma cell line. Only compounds 4/5 (EC50 = 36.0 µg/mL (32.7 µM)) exhibited moderate cytotoxic activity. This work presents the first chemical and biological investigation of Microglossa afzelii and reports, for the first time, on the isolation of saponins in the genus Microglossa.

Pennogenin-3-O-α-L-Rhamnopyranosyl-(1→2)-[α-L-Rhamnopyranosyl-(1→3)]-ß-D-Glucopyranoside (Spiroconazol A) Isolated from Dioscorea bulbifera L. var. sativa Induces Autophagic Cell Death by p38 MAPK Activation in NSCLC Cells.

In our previous study, we reported the isolation of pennogenin-3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→3)]-ß-D-glucopyranoside (spiroconazol A), a steroidal saponin, from the flowers of Dioscorea bulbifera L. var. sativa. In the present study, we aimed to investigate the effects of spiroconazol A on autophagy and its underlying mechanisms in A549 and NCI-H358 human non-small cell lung cancer (NSCLC) cells. Spiroconazol A inhibited the proliferation of NSCLC cells in a concentration- and time-dependent manner. To determine the type of programmed cell death induced by spiroconazol A, we performed a characterization of apoptosis in spiroconazol A-treated A549 cells. Our results showed that spiroconazol A significantly suppressed A549 cell viability but did not influence cell apoptosis because phosphatidylserine and caspase activation were not detected. Furthermore, spiroconazol A treatment upregulated the expression of LC3-II and autophagy-related Beclin-1 protein, suggesting that spiroconazol A induces autophagy in A549 cells. Moreover, spiroconazol A activated the phosphorylation of p38 mitogen-activated protein kinase (MAPK) but did not affect the phosphorylation of Janus kinase or ERK1/2. Notably, SB203580, a p38 MAPK inhibitor, had a significant inhibitory effect on spiroconazol A-induced autophagic cell death in A549 cells. Our results indicated that spiroconazol A-induced autophagy is dependent on p38 MAPK signaling and has potential as a therapeutic target in NSCLC.

Chemotaxonomy and Antibacterial Activity of the Extracts and Chemical Constituents of Psychotria succulenta Hiern. (Rubiaceae).

The use of natural products for medicinal purposes is becoming more and more common nowadays, as evidenced by the presence in plants of secondary metabolites with different potentials such as antioxidant and antibacterial properties. We evaluated in this work the antimicrobial activities of the extracts and some isolated compounds from the seeds of Psychotria succulenta Hiern. (Rubiaceae), a Cameroonian medicinal plant traditionally used to cure microbial infections. The ethanol extract was prepared by maceration and extracted with ethyl acetate and n-butanol. The EtOAc (m = 168 g) and n-BuOH (m = 20 g) extracts were further fractionated by silica gel column chromatography to isolation of compounds. Their structures were elucidated by spectroscopic analysis and by comparison with published data. The antibacterial activity of extracts and compounds was assessed by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against pathogenic bacteria. Thirteen compounds including four alkaloids (veprisine (1), naucleofficine III (2), vepridimerine B (3), and vepridimerine C (4)), three triterpenes (barbinervic acid (5), 3-O-α-L-rhamnopyranosyl quinovic acid (6), and oleanolic acid (7)), one steroid (ß-sitosterol-3-O-ß-D-glucopyranoside (8)), four phenolic compounds (scopoletin (9), gallic acid (10), quercetin-3-O-ß-D-glucopyranoside (11), and kaempferol 3-O-α-L-rhamnopyranoside-7-O-α-L-rhamnopyranoside (12)), and one iridoid (borreriagenin (13)) were isolated from the EtOAc and n-BuOH extracts. These compounds were identified by 1D and 2D NMR combined analysis as well as by melting point comparison. The EtOH, EtOAc, and n-BuOH extracts exhibited significant antibacterial activities (MIC = 32-128 µg/mL; MBC = 64-256 µg/mL) against Staphylococcus aureus (Gram-positive bacterium), Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonia (Gram-negative bacteria). Among the isolated compounds, scopoletin (9) showed a moderate activity against Klebsiella pneumoniae with MIC and MBC values of 16 µg/mL and 32 µg/mL, respectively. It appears that, chemotaxonomically, some of the isolated compounds have already been obtained from the genus Psychotria but to the best of our knowledge, this is the first report on the phytochemical investigation of P. succulenta. Although many other studies need to be achieved, our results support the use of P. succulenta in traditional medicine to cure infectious diseases particularly those caused by the tested bacteria.

Constituents from ripe figs of Ficus vallis-choudae Delile (Moraceae) with antiplasmodial activity.

Ripe figs, barks, and wood of Ficus vallis-choudae are used in traditional medicine against several conditions including nausea and malaria. However, its use is still to be scientifically documented and validated. Hence, the aim of the present work was to evaluate the antiplasmodial activity of the dichloromethane-methanol (DCM-MeOH (1:1)) crude extract, their hexane, dichloromethane, ethyl acetate, and methanoli fractions, as well as the isolated chemical constituents. The chemical study of the DCM-MeOH (1:1) crude extract of F. vallis-choudae figs led to the isolation of fifteen (15) known compounds identified based on their spectroscopic data [one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR), mass spectrometry] and by comparison of these data with those reported in the literature. Some of the isolated compounds were assessed in vitro for their antiplasmodial activity against Plasmodium falciparum chloroquine-sensitive 3D7 (Pf3D7) and multidrug-resistant Dd2 strains. The dichloromethane fraction exhibited very good antiplasmodial activity against both strains with IC50 values of 13.86 µg/mL and 8.18 µg/mL, respectively. Among the tested compounds, wighteone (2) was the most active against P. falciparum 3D7 (IC50 = 24.6 ± 1.5 µM) and Dd2 (IC50 = 11.9 ± 2.4 µM) strains. The obtained results could justify the traditional uses of F. vallis-choudae against malaria. Wighteone appears to be the most active ingredient. However, further consideration of this compound as starting point for antimalarial drug discovery will depend upon its selectivity of action towards Plasmodium parasites. HIGHLIGHTS: • 15 (fifteen) compounds were isolated from the dichloromethane-methanol extract of Ficus vallis-choudae. • Their structures were determined on the basis of their spectroscopic data. • The dichloromethane fraction showed promising activities on the Pf3D7 and PfDd2 strains with IC50 values of 13.86 and 8.18 µg/mL, respectively. • Wighteone was the most active compound against PfDd2 (IC50 = 11.9 ± 2.4 µM).

Two new triterpenoid saponins: telephiifoliosides A and B from the roots of Corrigiola litoralis subsp. telephiifolia (Pourr.) Briq.

The polar fraction of the MeOH extract of the roots of Corrigiola litoralis subsp. telephiifolia (Pourr.) Briq. (Caryophyllaceae) was investigated for its constituents and two previously unreported monodesmosides triterpene saponins, telephiifoliosides A and B (1 and 2), along with the known bonushenricoside A (3) were isolated. Their structures were elucidated by combined spectroscopic and spectrometric techniques (1H NMR, 13C NMR, HSQC, 1H-1H COSY, HMBC, TOCSY, NOESY, HRESIMS) and chemical methods. The structures of the new saponins were established as; 3-O-α-L-arabinopyranosyljaligonic acid (1), and 3-O-α-L-arabinopyranosylphytolaccagenin ester (2). Upon evaluation of the antiproliferative activity on human malignant epithelial (HeLa) cells, none of the isolated compounds was efficient at the concentration of 33 µM. [Formula: see text]HighlightsThis is the first phytochemical study on Corrigiola litoralis subsp. telephiifolia.Two new saponins were isolated from the roots of Corrigiola litoralis subsp. telephiifolia.The isolated compounds were tested for their antiproliferative activity.

Cameroonian medicinal plants as potential candidates of SARS-CoV-2 inhibitors.

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic instigated by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) which changed the daily train of the world's population and cause several dead. Despite the significant efforts made in developing vaccines and therapeutic drugs, there is currently no available effective treatment against this new coronavirus infection, hence the need to continue research which is aimed at limiting the progression of this virus. The present study which has as objective to carry out in silico studies on the metabolites of some Cameroonian medicinal plants of the Asteraceae family with a view to propose potential molecules to fight against COVID-19. The selected plants are commonly used to treat respiratory infectious diseases, and for this reason they may contain some constituents which could exhibit an antiviral activity against SARS-CoV-2. In this work, a set of 74 naturally occurring compounds are computed with SARS-CoV-2 main protease protein (PDB ID: 6lu7) and spike protein (PDB ID: 6m0j) for their affinity and stability using binding energy analysis and molecular docking. Chrysoeriol-7-O-ß-D-glucuronopyranoside (compound 16) has showed promising results including excellent Absorption, Distribution, Metabolism and Excretion (ADME) parameters as well as insignificant toxicity. Finally, the stability of this compound is complex with the two proteins validated through molecular dynamics (MD) simulation, they displayed stable trajectory and molecular properties with consistent interaction profile in molecular dynamics simulations. These findings call for further in vitro and in vivo challenges of phytoconstituents against the COVID-19 as a potential agent to fight the spread of this dramatic pandemic.Communicated by Ramaswamy H. Sarma.

Botanicals and phytochemicals from the bark of Hypericum roeperianum (Hypericaceae) had strong antibacterial activity and showed synergistic effects with antibiotics against multidrug-resistant bacteria expressing active efflux pumps.

ETHNOPHARMACOLOGICAL RELEVANCE: Infections due to multidrug-resistant (MDR) bacteria constitute a real problem in the public health worldwide. Hypericum roeperianum Schimp. ex A. Rich (Hypericaceae) is used traditionally for treatment of various ailments such as abdominal pains, constipation, diarrhea, indigestion, nausea, and bacterial diseases. AIM OF THE STUDY: This study was aimed at investigating the antibacterial and antibiotic-modifying activity of the crude methanol extracts (HRB), ethyl-acetate soluble fraction (HRBa), residual material (HRBb), and 11 compounds from the bark of Hypericum roeperianum against multi-drug resistant (MDR) bacteria expressing active efflux pumps. MATERIALS AND METHODS: The antibacterial activity, the efflux pump effect using the efflux pump inhibitor (EPI), phenylalanine-arginine-ß-naphthylamide (PAßN), as well as the antibiotic-modifying activity of samples were determined using the broth micro-dilution method. Spectrophotometric methods were used to evaluate the effects of HRB and 8,8-bis(dihydroconiferyl) diferulate (11) on bacterial growth, and bacterial membrane damage, whereas follow-up of the acidification of the bacterial culture was used to study their effects on bacteria proton-ATPase pumps. RESULTS: The crude extract (HRB), HRBa, and HRBb had selective antibacterial activity with MICs ranging from 16 to 512 µg/mL. Phytochemical 11 displayed the best antibacterial activity (0.5 ≤ MIC ≤ 2 µg/mL). The activity of HRB and 11 in the presence of EPI significantly increased on the tested bacteria strains (up to 32-fold). The activity of cloxacillin (CLO), doxycycline (DOX), and tetracycline (TET), was considerably improved (up to 64-fold) towards the multidrug-resistant Enterobacter aerogenes EA-CM64 strain. The crude extract (HRB) and 11 induced the leakage of bacterial intracellular components and inhibited the proton-ATPase pumps. CONCLUSIONS: The crude extract (HRB) and 8,8-bis(dihydroconiferyl)diferulate from the bark of Hypericum roeperianum are good antibacterial candidates that deserve further investigations to achieve antibacterial drugs to fight infections involving MDR bacteria.

Hepatoprotective effects of extracts, fractions and compounds from the stem bark of Pentaclethra macrophylla Benth: Evidence from in vitro and in vivo studies.

AIM: To identify the bioactive hepatoprotective components of the ethanol extract of Pentaclethra macrophylla stem bark using in vitro and in vivo approaches. METHODS: The bioguided-fractionation of the ethanol extract was based on the substances' capacity to prevent in vitro, the lipid peroxidation of hepatocytes' membranes induced by hydrogen peroxide. For the in vivo hepatoprotective test, mice were treated orally with the ethyl acetate (EtOAc) fraction of the ethanol extract at doses of 50 and 75 mg/kg/day for one week and subjected to d-galactosamine/lipopolysaccharide (GaIN/LPS)-induced hepatotoxicity. Blood samples were collected for alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), TNF-α and IL-1ß assays. The liver was harvested for histological and biochemical (proteins, glutathione (GSH), catalase and superoxide dismutase (SOD)) analysis. RESULTS: The ethanol extract and fractions induced concentration-dependent inhibition of lipid peroxidation (IC50: 3.21-48.90 µg/mL) greater than that of silymarin (IC50: 117.4 µg/mL). The purification of the sub-fractions of EtOAc fraction yielded: (7R)-7-hydroxyhexacosanoic acid (1), (7R)-1-(7-hydroxyhexacosanoyl) glycerol (2), bergenin (3), 11-O-galloylbergenin (4), 2-hydroxymethyl-5-(2-hydroxypropan-2-yl)phenol (5), ß-sitosterol 3-O-ß-d-glucopyranosyl (6) and ß-sitosterol (7)), among which 11-O-galloylbergenin (IC50:1.8 µg/mL) was the most effective. The EtOAc fraction significantly reduced the serum level of ALAT, ASAT and TNF-α in vivo. This EtOAc fraction increased the liver protein content and protected the liver against structural damages, but did not boost the endogenous antioxidant parameters. CONCLUSION: The stem bark of Pentaclethra macrophylla possesses hepatoprotective effects that may result from its capacity to inhibit lipid peroxidation and could be attributed to its active components 3, 4 and 2.

Effectiveness of eight essential oils against two key stored-product beetles, Prostephanus truncatus (Horn) and Trogoderma granarium Everts.

The use of chemical pesticides to preserve food commodities is a global issue of concern due to their negative effect on the environment and public health. In recent years, the European Union is trying to reduce their use, favoring alternative or complementary approaches based on natural products. In this scenario, plant-borne essential oils (EOs) represent valid options for Integrated Pest Management (IPM) programs. In the present study, the insecticidal effect of eight EOs obtained from plants from different parts of the world, namely Mentha longifolia, Dysphania ambrosioides, Carlina acaulis, Trachyspermum ammi, Pimpinella anisum, Origanum syriacum, Cannabis sativa and Hazomalania voyronii, were evaluated against two stored-product insect species of economic importance, Prostephanus truncatus and Trogoderma granarium. Simulating a small-scale stored-product conservation environment, an AG-4 airbrush was used to spray maize and wheat with 500 and 1000 ppm of EOs, then T. granarium and P. truncatus were exposed to the stored products and mortality was evaluated over selected time intervals (4, 8, and 16 h, and 1, 2, 3, 4, 5, 6, and 7 days). The EO of C. acaulis exhibited high efficacy against P. truncatus adults at both tested concentrations by killing > 97% of the individuals exposed to treated maize within 3 days at 500 ppm. The EO of D. ambrosioides eliminated all T. granarium adults exposed to 1000 ppm-treated wheat 2 days post-exposure. At this exposure interval, 91.1% of the exposed T. granarium adults died on wheat treated with 1000 ppm of C. acaulis EO. The EO of M. longifolia at both tested concentrations was the most effective against T. granarium larvae, leading to 97.8% mortality at 500 ppm after 3 days of exposure, and 100% mortality at 1000 pm 2 days post-exposure. At 1000 ppm, the EOs of D. ambrosioides and P. anisum led to 95.6 and 90% mortality, respectively, to larvae exposed to treated wheat for 7 days. Overall, our research shed light on the potential of selected EOs, with special reference to M. longifolia, D. ambrosioides, C. acaulis and P. anisum, which could be considered further to develop effective and alternative grain protectants to manage P. truncatus and T. granarium infestations.

Acaricidal activity, mode of action, and persistent efficacy of selected essential oils on the poultry red mite (Dermanyssus gallinae).

In this work, the essential oils (EOs) from Litchi chinensis, Clausena anisata, Heracleum sphondylium, Pimpinella anisum, Lippia alba, Crithmum maritimum and Syzygium aromaticum were tested for their contact toxicity against the poultry red mite, Dermanyssus gallinae, a deleterious ectoparasite of aviary systems. In addition, in order to give insights on their mode of action and effectiveness, the vapor phase and residual toxicity tests were also performed. Results showed that amongst all the tested EOs, that of S. aromaticum demonstrated the highest contact toxicity, with a LC50 value of 8.9 µg/mL, followed by C. maritimum and L. chinensis EOs, with LC50 values of 23.7 and 24.7 µg/mL, respectively. L. chinensis and C. anisata EOs showed higher vapor toxicity than the other EOs. L. chinensis and S. aromaticum EOs showed promising toxic effects up to 4 days post-application. Taken together, these results highlighted L. chinensis and S. aromaticum as two promising sources of biopesticides, able to cause severe contact, vapor and residual toxicity in the poultry red mites. Given the wide plant cultivation and uses in foodstuffs, cosmetics, flavour and fragrances, these EOs may be considered cheap and ready-to-use products as valid, eco-friendly alternatives to pesticides currently used in the aviary systems.

Acute and sub-acute toxicity of the aqueous extract from the stem bark of Tetrapleura tetrapteura Taub. (Fabaceae) in mice and rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Tetrapleura tetrapteura Taub. is a leguminous multipurpose tree (Fabaceae) indigenous to tropical Africa. Fruits, seeds and stem bark infusions or decoctions of Tetrapleura tetrapteura Taub. are used to treat many diseases, such as gastric ulcer, rheumatism, malaria, hypertension and hyperlipidemia. AIM OF THE STUDY: This work was conducted to evaluate the acute and sub-acute toxicity of the aqueous extract of Tetrapleura tetrapteura Taub. (AETT) stem barks. MATERIALS AND METHODS: For the study of acute toxicity, single oral doses of 2000 mg/kg and 5000 mg/kg of AETT were administrated to male and female Balb/c mice, followed by observation of mice for 14 days. In the study of sub-acute toxicity, 48 albino wistar rats of both genders were randomly divided into six groups of 8 animals and they were daily and orally administrated for twenty eight days. The animal's test groups and satellite test group were administrated with the extract (AETT) at the doses of 100, 200 and 400 mg/kg and 400 mg/kg respectively. On the 29th day, the satellite group (control 2 and satellite 400 mg/kg) were observed during two more weeks. General behavior changes, mortality, body weight of animal, water and food intake were recorded during the study period. At the end of each treatment period, biochemical and hematological parameters were measured and histological examinations of liver and kidneys sections performed. RESULTS: Up to 5000 mg/kg single dose administration of AETT for fourteen days registered no death animal. In sub-acute study, no mortality was recorded in various experimental groups. Significant reductions in body weight, water and food intake were recorded in all treated animals. Relative weights of liver, kidneys, stomach, spleen, lungs, and heart of treated animals remained unchanged. Significant increases in the number of platelets as well as in serum ALAT level were recorded in rats, treated with 400 mg/kg of AETT. Female rat liver histology showed, at a higher dose of AETT, a slight congestion of portal vein. CONCLUSION: AETT is safe after therapeutic (200 mg/kg) or acute administration. Higher dose (400 mg/kg) administered for longer period showed signs of liver toxicity.