Quassinoids from Twigs of Harrisonia perforata (Blanco) Merr and Their Anti-Parkinson's Disease Effect.

Six new C-20 and one new C-19 quassinoids, named perforalactones F-L (1-7), were isolated from twigs of Harrisonia perforata. Spectroscopic and X-ray crystallographic experiments were conducted to identify their structures. Through oxidative degradation of perforalactone B to perforaqussin A, the biogenetic process from C-25 quassinoid to C-20 via Baeyer-Villiger oxidation was proposed. Furthermore, the study evaluated the anti-Parkinson's disease potential of these C-20 quassinoids for the first time on 6-OHDA-induced PC12 cells and a Drosophila Parkinson's disease model of PINK1B9. Perforalactones G and I (2 and 4) showed a 10-15% increase in cell viability of the model cells at 50 µM, while compounds 2 and 4 (100 µM) significantly improved the climbing ability of PINK1B9 flies and increased the dopamine level in the brains and ATP content in the thoraces of the flies.

Antiplasmodial and cytotoxic effects of the methanol extract, canthinone alkaloids, squalene- and protolimonoid-type triterpenes from Homalolepis suffruticosa roots.

ETHNOPHARMACOLOGICAL RELEVANCE: Different species of the Simaroubaceae family are used in traditional medicine to treat malaria. Among these is Homalolepis suffruticosa (syn. Simaba suffruticosa and Quassia suffruticosa), which is native to Central Brazil and popularly known as calunga. However, there is a lack of investigation concerning its antimalarial effects. AIM OF THE STUDY: To investigate the antiplasmodial and cytotoxic effects of the isolated metabolites and methanol extract from H. suffruticosa roots as well as to conduct the dereplication of this extract aiming to characterize its metabolic profile by UPLC-DAD-ESI-MS/MS. MATERIALS AND METHODS: Methanol extract of the H. suffruticosa roots and six isolated compounds were evaluated against chloroquine-resistant Plasmodium falciparum W2 strain by the PfLDH method and cytotoxicity in HepG2 cells by the MTT assay. Dereplication of the extract was performed by UPLC-DAD-ESI-MS/MS. RESULTS: The six isolated compounds disclosed high to moderate antiplasmodial activity (IC50 0.0548 ± 0.0083 µg/mL to 26.65 ± 2.40 µg/mL) and cytotoxicity was in the range of CC50 0.62 ± 0.33 µg/mL to 56.43 ± 2.54 µg/mL, while 5-metoxycantin-6-one proved to be the most potent constituent of the six assayed ones. The methanol extract of the roots showed high in vitro antiplasmodial activity (IC50 1.88 ± 0.56 µg/mL), moderate cytotoxicity (CC50 41.93 ± 2.30 µg/mL), and good selectivity index (SI = 22.30). Finally, C20 quassinoids and canthin-6-one alkaloids were putatively identified in the H. suffruticosa methanol extract by LC-MS. CONCLUSIONS: Taken together, the isolated compounds, mainly the 5-metoxycantin-6-one and the methanol extract from H. suffruticosa roots, disclose good antiplasmodial activity, supporting the ethnopharmacological history of the Simaroubaceae species as traditional antimalarial drugs.

In vitro inhibition of protein glycation and advanced glycation end products formation by hydroethanolic extract and two fractions of Simaba trichilioides roots.

Long-term hyperglycemia maintenance is responsible for increased protein glycation and formation of advanced glycation end products (AGEs), both are associated with the onset of diabetes mellitus complications. Efforts have been made to discover new agents having antiglycation potential. The aim of this study was to investigate the effects of the hydroethanolic extract and the ethyl acetate and methanolic fractions of Simaba trichilioides roots on the formation of AGEs. In an in vitro model system of protein glycation, incubations with hydroethanolic extract, ethyl acetate or methanolic fractions of S. trichilioides decreased the fluorescent AGEs, and markers of tyrosine and tryptophan oxidation. Protein crosslinking was reduced in the presence of the ethyl acetate fraction of S. trichilioides. Simaba trichilioides roots seem to be a promising source of compounds having ability to prevent glycoxidation changes, with potential applications in complementary therapies for management of diabetic complications.

Traditional use and scientific investigations of the medicinal plant Simaba cedron Planch.

Simaba cedron Planch (Simaroubaceae) has frequently been reported as a traditional remedy against snake bites, malaria, gastrointestinal and other disorders. Starting in the 18th century, European physicians and researchers made several efforts to verify the reported virtues and to isolate active principles. Most important achievements are reviewed her. From modern investigations, an anti-malarial activity seems plausible due to the quassinoids contained. An effect against snake-bites seems questionable, research about the usefulness against gastrointestinal disorders, which is also reported, is missing. Other Simaroubaceae, however, are under current investigation now.

Ailanthone exerts an antitumor function on the development of human lung cancer by upregulating microRNA-195.

BACKGROUND: Lung cancer is a common leading cause of cancer-related death worldwide. Ailanthone, a natural compound isolated from Chinese herb Ailanthus altissima, has been reported to exert antiproliferative effects on various cancer cells. METHODS: The present study aimed to investigate the role of ailanthone in the lung cancer cells and the correlation between the ailanthone and microRNA (miR)-195. The cell viability, proliferation, and apoptosis were determined by cell counting kit-8 assay, bromodeoxyuridine incorporation method, annexin V-fluorescein isothiocyanate/propidium iodide assay, respectively. Apoptosis- and autophagy-related proteins, as well as regulatory factors in the signaling pathways, were analyzed by Western blot method. The expression of miR-195 was quantified by quantitative reverse transcription-polymerase chain reaction. RESULTS: The results confirmed that ailanthone was involved in the lung cancer cell progress by inhibiting cell viability and proliferation, but promoted cell apoptosis and autophagy. We also found that ailanthone upregulated the expression of miR-195. Further, the downregulated miR-195 inhibited the apoptosis and autophagy induced by ailanthone. Moreover, our studies revealed that miR-195 inhibitor promoted the phosphorylation of PI3K, AKT, JAK, and STAT3, which was inhibited by ailanthone. CONCLUSION: All these findings suggest that ailanthone plays key roles in lung cancer progress and is closely correlated with miR-195 expression.

In vitro nematicidal effect of Chenopodium ambrosioides and Castela tortuosa n-hexane extracts against Haemonchus contortus (Nematoda) and their anthelmintic effect in gerbils.

The in vitro nematicidal effect of Chenopodium ambrosioides and Castela tortuosa n-hexane extracts (E-Cham and E-Cato, respectively) on Haemonchus contortus infective larvae (L3) and the anthelmintic effect of these extracts against the pre-adult stage of the parasite in gerbils were evaluated using both individual and combined extracts. The in vitro confrontation between larvae and extracts was performed in 24-well micro-titration plates. The results were considered 24 and 72 h post confrontation. The in vivo nematicidal effect was examined using gerbils as a study model. The extracts from the two assessed plants were obtained through maceration using n-hexane as an organic agent. Gerbils artificially infected with H. contortus L3 were treated intraperitoneally with the corresponding extract either individually or in combination. The results showed that the highest individual lethal in vitro effect (96.3%) was obtained with the E-Cham extract at 72 h post confrontation at 40 mg/ml, followed by E-Cato (78.9%) at 20 mg/ml after 72 h. The highest combined effect (98.7%) was obtained after 72 h at 40 mg/ml. The in vivo assay showed that the individual administration of the E-Cato and E-Cham extracts reduced the parasitic burden in gerbils by 27.1% and 45.8%, respectively. Furthermore, the anthelmintic efficacy increased to 57.3% when both extracts were administered in combination. The results of the present study show an important combined nematicidal effect of the two plant extracts assessed against L3 in gerbils.

12ß-Acetyloxyperforatin, a New Limonoid from Harrisonia Perforata.

A new A, D-seco limonoid, named 12-acetyloxyperforatin (1), along with three known ones, were isolated from the leaves of Harrisonia perforata. Their structures were elucidated on the basis of spectroscopic analysis, including extensive NMR techniques and computational modelling. These compounds showed no inhibitory activity against the 11ß-HSD1 enzyme.

Anti-plasmodial effect of plant extracts from Picrolemma huberi and Picramnia latifolia.

BACKGROUND: Malaria is an infectious disease caused by parasites of the genus Plasmodium, of which Plasmodium vivax and Plasmodium falciparum are the major species that cause the disease in humans. As there are relatively few alternatives for malaria treatment, it is necessary to search for new chemotherapeutic options. Colombia possesses a great diversity of plants, which are potential sources of new compounds of medical interest. Thus, in this study the antiplasmodial effect of extracts from two species of plants from the families Simaroubaceae and Picramniaceae (Picramnia latifolia and Picrolemma huberi) was evaluated in vitro and in vivo. These plants were chosen because they contain secondary metabolites with interesting medicinal effects. RESULTS: The ethanolic extracts of both species were highly active with IC50: 1.2 ± 0.19 µg/mL for P. latifolia and IC50: 0.05 ± 0.005 µg/mL for P. huberi. The P. latifolia extract had a stage specific effect on trophozoites and inhibited parasite growth in vivo by 52.1 ± 3.4%, evaluated at 1000 mg/kg in Balb/c mice infected with Plasmodium berghei. On the other hand, evaluated at 150 mg/kg body weight in the same murine model, the ethanolic extract from P. huberi had an antiplasmodial effect in all the asexual intraerythrocytic stages of P. falciparum FCR3 and inhibited the parasitic growth in 93 ± 32.9%. CONCLUSIONS: This is the first report of anti-malarial activity for these two species of plants. Thus, P. latifolia and P. huberi are potential candidates for the development of new drugs for treating malaria.

Glaucarubulone glucoside from Castela macrophylla suppresses MCF-7 breast cancer cell growth and attenuates benzo[a]pyrene-mediated CYP1A gene induction.

Quassinoids often exhibit antioxidant and antiproliferative activity. Emerging evidence suggests that these natural metabolites also display chemopreventive actions. In this study, we investigated the potential for the quassinoid glaucarubulone glucoside (Gg), isolated from the endemic Jamaican plant Castela macrophylla (Simaroubaceae), to display potent cytotoxicity and inhibit human cytochrome P450s (CYPs), particularly CYP1A enzymes, known to convert polyaromatic hydrocarbons into carcinogenic metabolites. Gg reduced the viability of MCF-7 breast adenocarcinoma cells (IC50 = 121 nm) to a greater extent than standard of care anticancer agents 5-fluorouracil, tamoxifen (IC50 >10 µm) and the tamoxifen metabolite 4-hydroxytamoxifen (IC50 = 2.6 µm), yet was not cytotoxic to non-tumorigenic MCF-10A breast epithelial cells. Additionally, Gg induced MCF-7 breast cancer cell death. Gg blocked increases in reactive oxygen species in MCF-10A cells mediated by the polyaromatic hydrocarbon benzo[a]pyrene (B[a]P) metabolite B[a]P 1,6-quinone, yet downregulated the expression of genes that promote antioxidant activity in MCF-7 cells. This implies that Gg exhibits antioxidant and cytoprotective actions in non-tumorigenic breast epithelial cells and pro-oxidant, cytotoxic actions in breast cancer cells. Furthermore, Gg inhibited the activities of human CYP1A according to non-competitive kinetics and attenuated the ability of B[a]P to induce CYP1A gene expression in MCF-7 cells. These data indicate that Gg selectively suppresses MCF-7 breast cancer cell growth without impacting non-tumorigenic breast epithelial cells and blocks B[a]P-mediated CYP1A induction. Taken together, our data provide a rationale for further investigations of Gg and similar plant isolates as potential agents to treat and prevent breast cancer. Copyright © 2017 John Wiley & Sons, Ltd.

(±)-Perforison A, A Pair of New Chromone Enantiomers from Harrisonia perforata.

(+)-Perforison A and (-)-perforison A, a new pair of chromone enantiomers, along with four known compounds, were isolated from the leaves and stems of Harrisonia perforata. Their structures and absolute configurations were determined on the basis of extensive analysis of spectroscopic data and electronic circular dichroism (ECD) calculations. The cytotoxic activities in vitro of these compounds were evaluated, but none showed significant activity.

16-nor Limonoids from Harrisonia perforata as promising selective 11ß-HSD1 inhibitors.

Two new 16-nor limonoids, harperspinoids A and B (1 and 2), with a unique 7/5/5/6/5 ring system, have been isolated from the plant Harrisonia perforate together with a known one, Harperforin G (3). Their structures were elucidated by NMR spectroscopy, X-ray diffraction analysis and computational modelling. Compound 1 exists as polymorphic crystals. Conformations of 1 in solution were further discussed based on the computational results. These compounds exhibited notable inhibitory activity against the 11ß-HSD1 enzyme. Compound 3 had potencies for the inhibition of human 11ß-HSD1 with high selectivity against 11ß-HSD2 (IC50 0.58 µM, SI > 174). Molecular docking and quantitative structure-activity relationship studies revealed a mixed regulatory mechanism.

The quassinoid isobrucein B reduces inflammatory hyperalgesia and cytokine production by post-transcriptional modulation.

Isobrucein B (1) is a quassinoid isolated from the Amazonian medicinal plant Picrolemma sprucei. Herein we investigate the anti-inflammatory and antihyperalgesic effects of this quassinoid. Isobrucein B (1) (0.5-5 mg/kg) inhibited carrageenan-induced inflammatory hyperalgesia in mice in a dose-dependent manner. Reduced hyperalgesia was associated with reduction in both neutrophil migration and pronociceptive cytokine production. Pretreatment with 1 inhibited in vitro production/release of cytokines TNF, IL-1ß, and KC/CXCL1 by lipopolysaccharide-stimulated macrophages. To investigate its molecular mechanism, RAW 264.7 macrophages with a luciferase reporter gene controlled by the NF-κB promoter were used (RAW 264.7-Luc). Quassinoid 1 reduced the luminescence emission by RAW 264.7-Luc stimulated by different compounds. Unexpectedly, NF-κB translocation to macrophage nuclei was not inhibited by 1 when evaluated by Western blotting and immunofluorescence. Furthermore, quassinoid 1 did not change the levels of TNF mRNA transcription in stimulated macrophages, suggesting post-transcriptional modulation. In addition, constitutive expression of luciferase in RAW 264.7 cells transiently transfected with a plasmid containing a universal promoter was inhibited by 1. Thus, isobrucein B (1) displays anti-inflammatory and antihyperalgesic activities by nonselective post-transcriptional modulation, resulting in decreased production/release of pro-inflammatory cytokines and neutrophil migration.

[Chemical constituents from the twigs and leaves of Harrisonia perforate].

This study was performed to investigate the chemical constituents in the twigs and leaves of Harrisonia perforate. Six compounds were isolated from the 95% EtOH extract of the twigs and leaves of Harrisonia perforate by silica gel, ODS, Sephadex LH-20 column chromatographies and preparative HPLC. On the basis of chemical properties and spectra data, these compounds were identified as harriperfin E (1), kihadanin A (2), kihadanin B (3), 6α-acetoxyobacunol acetate (4), gardaubryone C (5), and ß-sitosterol methyl ether (6), respectively. Compound 1 is a new chromone, and compounds 2-6 are isolated from this plant for the first time.

Development and validation of RP-HPLC method to determine anti-allergic compound in Thai traditional remedy called Benjalokawichien.

Benjalokawichien (BLW) or Ya-Ha-Rak (HR) is a traditional remedy in the Nationaldrug list of herbal medicinal products AD 2012 of Thailand. For traditional use, BLW is used as antipyretic agent. It also has anti-allergic effect, particularly treating allergic rash. The ethanolic extract of BLW exhibited anti-allergic activity via inhibitory effect against a release ofbeta-hexosaminidase in RBL-2H3 cell line. Pectolinarigenin has been identified as the active compound ofBLW extract. In this study, a reversed-phase high performance liquid chromatography (RP-HPLC) method was developed in order to control quality ofpreparation in three aspects such as chemical fingerprint, quantification and stability of the ethanolic extract. The RP-HPLC was performed with a gradient mobile phase composed of 0.1% ortho phosphoric acid and acetronitrile, and peaks were detected at 331 nm. Based on validation results, this analytical method is precise, accurate and stable for quantitative determination ofpectolinarigenin. The amount ofpectolinarigenin in Benjalokawichien extract determined by this method was 18.50 mg/g ofextract. Therefore, this method could be consideredfor quality control ofBLWextract.

Inhibition of the calcineurin pathway by two tannins, chebulagic acid and chebulanin, isolated from Harrisonia abyssinica Oliv.

In order to discover and develop novel signaling inhibitors from plants, a screening system was established targeting the two-component system of Cryptococcus neoformans by using the wild type and a calcineurin mutant of C. neoformans, based on the counter-regulatory action of high-osmolarity glycerol (Hog1) mitogen-activated protein kinase and the calcineurin pathways in C. neoformans. Among 10,000 plant extracts, that from Harrisonia abyssinica Oliv. exhibited the most potent inhibitory activity against C. neoformans var. grubii H99 with fludioxonil. Bioassay-guided fractionation was used to isolate two bioactive compounds from H. abyssinica, and these compounds were identified as chebulagic acid and chebulanin using spectroscopic methods. These compounds specifically inhibited the calcineurin pathway in C. neoformans. Moreover, they exhibited potent antifungal activities against various human pathogenic fungi with minimum inhibitory concentrations ranging from 0.25 to over 64 µg/ml.

Gastro-protective effects of isobrucein B, a quassinoid isolated from Picrolemma sprucei.

Infusions of Picrolemma sprucei roots, stems and leaves are used in traditional medicine throughout the Amazon region from the Guianas to Brazil and Peru in the treatment of gastritis, intestinal helminths and malaria. As there are no studies describing its mode of action in providing a gastroprotective effect, we determined herein that one of the main constituents found in P. sprucei infusions, the quassinoid isobrucein B (IsoB), reduces some of the pathophysiological effects in a mouse model of non-steroidal anti-inflammatory drug (NSAID)-induced gastritis and provides mechanisms of action. Then, IsoB (1.17 g) was isolated from the roots and stems (6.5 kg) of P. sprucei. Its structure was confirmed by 1D and 2D (1)H and (13)C NMR, ESI-tof-MS, IR and UV. C57BL/6 strain mice were subcutaneously injected with IsoB (0.5-5 mg kg(-1)) or vehicle before oral administration of indomethacin and sacrificed later at different time points. Gastric damage was assessed by measuring lesion length. Leukocyte migration was evaluated based on leukocyte rolling and adhesion using intravital microscopy in the mesenteric microcirculation and tissue MPO activity. Stomach extract cytokine (TNFα, IL-1ß and KC/CXCL1) and prostaglandin E2 (PGE2) levels were measured by ELISA and RIA, respectively. IsoB pre-treatment (0.5-5.0 mg kg(-1)) significantly reduced the formation of indomethacin-induced stomach lesions in a dose-dependent manner. The decrease in stomach lesions was associated with less observed leukocyte rolling, decreased leukocyte adhesion and less neutrophil infiltration (MPO activity). IsoB (1 mg kg(-1)) pre-treatment did not prevent indomethacin-induced decreases in stomach PGE2 levels. However, IL-1ß and KC/CXCL1 levels were inhibited by this same IsoB dosage, whereas TNF-α was unchanged. IsoB may be a prototypic compound to provide protective effects against NSAID-induced gastritis and possibly other gastropathies. Moreover, IsoB gastroprotective action may be due to a reduction in IL-1ß and KC/CXCL1 production/release and leukocyte rolling, adhesion and migration.

Tripanocide and antibacterial activity ofAlvaradoa subovata Cronquist extracts / Actividad tripanocida y antibacteriana de extractos de Alvaradoa subovata Cronquist

We studied antioxidant, antibacterial and tripanocide activities of Alvaradoa subovata extracts. The ethanolic extracts showed the greatest DPPH radical scavenging capacity, especially that of bark with an IC50 = 4.7 +/- 0.18 ug/mL. Wood dichloromethane extract displayed growth inhibition of the phytopathogenic bacteria Xanthomona axonopodis in the disk diffusion assay and showed a MIC value of 100 ug/ml. It also showed growth inhibition of Trypanosoma cruzi (IC50 = 0.063 +/- 0.003 mg/mL). A fraction of this extract, which has emodin as the main component, showed tripanocide activity (60 percent of growth inhibition at 100 ug/mL). The main compounds in wood dichloromethane extract were anthraquinones, identified as chrysophanol and emodin, and coumarins, of which scopoletin was identified. These three compound s could serve as analytical markers of the extract. The results of this study show that wood extract of A. subovata constitute a source of bioactive compounds such as antiparasitic and pesticides agents.

En el presente trabajo se estudió la actividad antioxidante, antibacteriana y tripanocida de extractos de Alvaradoa subovata. La mayor actividad depuradora de radicales libres se observó en el extracto etanólico de corteza (CI50 = 4.7 +/- 0.18 ug/mL). El extracto en diclorometano de madera inhibió el crecimiento de la bacteria fitopatógena Xanthomona axonopodis con una CIM = 100 ug/mL. El mismo extracto mostró inhibición del crecimiento de Trypanosoma cruzi (CI50 = 0.063 +/- 0.003 mg/mL). Una fracción de este extracto (100 ug/mL), cuyo componente mayoritario es emodina, inhibió en un 60 por ciento el crecimiento del parásito. Los compuestos mayoritarios detectados en el extracto de madera fueron antraquinonas, entre las cuales se identificaron emodina y crisofanol, y la cumarina escopoletina. Estos tres compuestos podrían servir como marcadores analíticos del extracto. Los resultados de este trabajo muestran que los extractos de A. subovata constituyen una fuente de compuestos bioactivos con potencial como antiparasitarios y plaguicidas.

Oxidative burst inhibitory and cytotoxic activity of constituents of the fruits of Odyendyea gabonensis.

The methanol extract of dried fruits of Odyendyea gabonensis afforded one new quassinoid [(-)-odyendanol (1)], one new canthin-6-one alkaloid [9-hydroxy-5-methoxycanthin-6-one (4)], and two new steroids [22E, 24R-stigmasta-5,22-diene-3,7-dione (7) and 22E,24R-stigmast-22-ene-3,7-dione (8)] along with fourteen known compounds. The structures of all compounds were established by analyzing the spectroscopic data. The ¹³C-NMR values of (-)-odyendene (2) and (-)-odyendane (3), as well as the single-crystal X-ray structure of 5-methoxycanthin-6-one (6) are also reported.The oxidative burst inhibitory activity of pure compounds 1-12 was determined by the chemoluminescence assay, and cytotoxic activities of compounds 2-6 against the human prostate cancer cell PC-3 line were evaluated. Compounds 1-6 exhibited a clear suppressive effect on the phagocytosis response upon activation with serum-opsonized zymosan in the range of IC50 = 0.9-2.0 µM versus ibuprofen with IC50 = 12.1 µM, while all canthin-6-one alkaloids (4-6) displayed moderate cytotoxic activity against the human prostate cancer cell PC-3 line, with IC50 values ranging from 13.5-15.4 µM versus doxorubicine with IC50 = 1.5 µM.

Actividad antioxidante, análisis fitoquímico y micrografía analítica de hojas de Castela tweedii (Simaroubaceae) / Antioxidant activity, phytochemical analisys and micrographic characterization of Castela tweedii (Simaroubaceae) leaves

Castela tweedii is a small tree belonging to Simaroubaceae family. Infusions of its leaves are used in folk medicine to treat gastrointestinal disorders and diarrhea. In this work, we evaluated the antioxidant activity of ethanol and dicloromethane leaves extracts against DPPH radical (2,2-difenilpicrilhidrazil) in order to justify, at least in part, its popular use. Ethanol extract showed scavenging activity, with an IC50=0.1288 mg/mL. Responsible compounds for these activity were tannins, flavonoids and phenylcarboxilic acids, among them we identified rutine and chlorogenic acid. Microscopic and histochemical analysis of leaves was carry out to developed useful characterizations that will allow a future identification and authentication of raw material: such as, the presence of mucilaginous hypodermis, leaf of dorsiventral structure, 1 to 2 rows of empalisade parenchyma with tannin deposits, anomocytic stomata in low epidermis and simple, unicellular trichomes in both epidermis.

Castela tweedii es un árbol de bajo porte perteneciente a la Familia Simaroubaceae, las infusiones de sus hojas son utilizadas en la medicina popular Argentina para el tratamiento de desordenes gastrointestinales y diarreas. Con el objetivo de fundamentar el uso popular de esta especie se evaluó la actividad antioxidante de los extractos etanólicos y diclorometánicos de forma cuantitativa y cualitativa frente al radical 2,2-difenilpicrilhidrazilo (DPPH); el extracto etanólico demostró actividad obteniéndose una CI50= 0,1288 mg/mL. El análisis fitoquímico mostró que los compuestos responsables de esta actividad fueron taninos, flavonoides y ácidos fenilcarboxílicos, entre ellos se identificó rutina y ácido clorogénico. Además se realizó el estudio morfoanatómico e histoquímico de las hojas que aportó datos de valor diagnostico para el control de calidad de la droga vegetal: presencia de una hipodermis mucilaginosa, estructura dorsiventral con una a dos hileras de parénquima en empalizada conteniendo taninos, estomas anomocíticos solo en la epidermis abaxial y tricomas simples unicelulares en ambas epidermis.

Antimicrobial prenylated acetophenones from berries of Harrisonia abyssinica.

The ripe berries of Harrisonia abyssinica yielded two new prenylated acetophenones, namely 5-(ethan-1'''-one)-4,6-dihydroxy-7-(3'',3''-dimethylallyl)-2 S-(1' S-hydroxy-1',5'-dimethylhex-4'-enyl)-2,3-dihydrobenzofuran (1) and 5-(2'''-hydroxyethan-1'''-one)-4,6-dihydroxy-7-(3'',3''-dimethylallyl)-2 S-(1' S-hydroxy-1',5'-dimethylhex-4'-enyl)-2,3-dihydrobenzofuran (2), herein named harronin I and harronin II, respectively. The compounds were isolated following activity guided fractionation and the structures were determined using 1D, 2D NMR spectroscopic, CD and MS spectrometric techniques. The methanol-dichloromethane mixture (1 : 1 v/v) crude extract exhibited strong antimicrobial activity against Candida albicans, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Lactobacillus casei. Harronin I (1) showed a MIC of 5 µg/mL against C. albicans, 6 µg/mL against B. cereus, and more than 20 µg/mL against other tested microorganisms. Harronin II (2) showed much weaker MIC values (> 100 µg/mL) against all the tested microorganisms.