Folk medicine, biological activity, and chemical profiles of Brazilian Acanthaceae (Lamiales) - A review.

INTRODUCTION: The botanical family Acanthaceae (order Lamiales) potentially comprises 4900 species in 191 genera with extensive morphological, habit and habitat diversity. The family is widely distributed throughout the world but is especially rich in tropical and subtropical regions. Many of its species have great ornamental importance and are broadly used for medicinal purposes in several countries of Asia and Africa. Brazil is a main center of diversity of the family, where they are distributed across all its biomes, mainly in the herbaceous-shrub stratum. Medicinal investigations about Brazilian species are scarce, the exception being a single native species, Justicia pectoralis Jacq., that is widely used and studied chemically. AIM OF THE REVIEW: This work compiled studies that indicated folk medicinal use, investigated biological activity, or evaluated the chemical composition of Brazilian species of Acanthaceae. MATERIAL AND METHODS: Medicinal uses, investigations of biological activities and chemical data were collected and summarized through bibliographic surveys. Tables were compiled to standardize the information and the appropriate references were gathered for each species. Registration of chemical components used in the treatment of ailments and in preserving health were emphasized with the aim of stimulating future investigations. RESULTS: The breadths of habitats and morphologies of the family are directly related to its chemical diversity, as confirmed here for Brazilian species. Although the investigated species represent less than 9% of the total richness of the family in Brazil, they encompass a great diversity of chemical substances. The data indicated folk medicinal uses for 26 species and biological tests for 23, while 30 species were investigated chemically. Ruellia and Justicia were the most researched genera with 12 and 11 species, representing approximately 14% and 7% of Brazilian species of each genus, respectively. Two species are native to other countries but become naturalized in Brazil. Studies of native species were carried out in different countries around the world, with many reports of medicinal uses and biological tests. Examples of uses include anticancer and antidepressant actions, as well as activities against respiratory problems and other diseases. CONCLUSIONS: This work highlights the chemical and biological diversity of the studied Brazilian species of Acanthaceae, which emphasizes the need to expand studies with native Brazilian species.

Differential expression of brummer and levels of TAG in different developmental stages Aedes aegypti (Diptera: Culicidae), including fasted adults.

Lipid storage in the form of triacylglycerol (TAG) is essential for insect life, as it enables flight, development, and reproduction. The activity of the lipase brummer (bmm) has been shown to be essential to insects' homeostasis. The objective of this study was to evaluate how bmm expression occurs in Aedes aegypti larvae and adults, and to observe TAG levels during fasting in adult females. The bmm sequence was identified in A. aegypti and exhibited a patatin-like phospholipase domain reinforced by the presence of a catalytic dyad with serine and aspartate residues, revealing a high degree of similarity with other organisms. Bmm expression was differentiated in the larvae and adult fat body (FB) following TAG reserve dynamics. Bmm was expressed three times in larval stages L3, L4, and pupae compared with L1 and L2, which could indicate its role in the maturation of these insects. In the postemergence (PE) and post-blood meal (PBM) FB of adult insects, bmm expression varied over several days. PE adults showed a pronounced bmm increase from the third day onward compared with those not subjected to fasting. This was accompanied by a decrease in TAG from the third day onward, suggesting the participation of bmm. Six hours after blood feeding, TAG levels increased in mosquitos reared in the absence of sucrose, suggesting lipid accumulation to guarantee reproduction. Bmm responded positively to fasting, followed by TAG mobilization in adult FB. During the previtellogenic period, bmm levels responded to low TAG levels, unlike the PBM period.

Larvicidal and Fungicidal Activity of the Leaf Essential Oil of Five Myrtaceae Species.

Myrtaceae is one of the most diverse and abundant botanical families, exhibiting wide diversity in the chemical composition of essential oils (EOs). EOs have various biotechnological applications such as controlling the populations of organisms that negatively impact humans. This study aimed to extract EOs from Myrtaceae species, chemically characterize them, and evaluate their larvicidal and fungicidal effects. EOs were extracted from the leaves of Eugenia brasiliensis, Eugenia uniflora, Psidium cattleyanum, Psidium guajava, and Syzygium cumini by hydrodistillation for 3 h and characterized by chromatographic analysis. Larvaes of Aedes aegypti and colonies of Fusarium oxysporum were subjected to increasing EO concentrations to determine the larvicidal and fungicidal potential. The EOs of Eugenia and Psidium species are primarily composed of sesquiterpenes (>80 %), whereas S. cumini EO is rich in monoterpenes (more than 60 %). The Eugenia species had similar amounts of oxygenated monoterpenes, which may explain their higher larvicidal potential compared to other species, with CL50 of 86.68 and 147.46 PPM, respectively. In addition to these two study species, S. cumini showed a high inhibition of fungal growth, with more than 65 % inhibition. We demonstrated that the actions of five EOs from Myrtaceae with different biological activities are associated with chemical diversity.

Acaricidal activity of a 2-methoxy-clovan-9-ol rich fraction from Eugenia copacabanensis (Myrtaceae) extract on Rhipicephalus microplus (Acari: Ixodidae).

Rhipicephalus microplus (Ixodidae, canestrini, 1888) is an invasive ectoparasite of cattle which causes high economic losses in emerging countries such as Brazil. Phytochemical compounds have been tested as an alternative to synthetic acaricides due to potentially lower mammalian toxicity. This study evaluated the acaricidal activity against R. microplus of the 2-methoxy-clovan-9-ol rich fraction obtained from Eugenia copacabanensis Kiaersk.leaves, a little known Myrtaceae species from the Brazilian Atlantic Forest. This fraction was obtained by maceration with methanol, partition with n-hexane and purification by normal-phase column chromatography. GC-MS, 1H and 13C NMR and IR analysis contributed to the identification of a major compound as the sesquiterpene 2-methoxy-clovan-9-ol, reported for the first time for the Myrtaceae family. The fraction was tested against R. microplus unfed larvae and engorged females and a 93% larval mortality was observed at the concentration of 50 mg mL-1. Lower concentrations of the solution tested demonstrated a significant difference in egg mass weight, hatching and control percentage. Experiments with 50.0 mg mL-1 showed significative results, with lower concentration and maximum efficacy for both assays. The IC50 values for unfed larvae and engorged females were 21.76 and 11.13 mg mL-1, respectively. These results were similar to those obtained in other studies with isolated botanical compounds and essential oils. The lower IC50 for engorged females than for unfed R. microplus larvae had also been described for other plant materials, including plants from the same Myrtaceae family. The present result suggested different mechanisms of action of the compound on the reproductive biology of engorged females, improving its effect against egg viability. These results are important for tick control, suggesting that 2-methoxy-clovan-9-ol could be a potential natural acaricidal product against both R. microplus unfed larvae and engorged females.

Siolmatra brasiliensis stem extract ameliorates antioxidant defenses and mitigates glycoxidative stress in mice with high-fat diet-induced obesity.

BACKGROUND: Obesity is accompanied by insulin resistance and glucose intolerance, which favor the onset of complications related to oxidative stress. The aim of this study was to investigate the effects and underlying mechanisms of hydroethanolic extract from Siolmatra brasiliensis stems on insulin resistance, glucose intolerance, advanced glycation end product (AGE) formation, and oxidative stress in mice with induced obesity. METHODS: C57BL-6 J mice were fed a high-fat diet for 14 weeks and treated with 125 or 250 mg/kg S. brasiliensis extract during the last 7 weeks. The study assessed glucose tolerance and insulin sensitivity, lipid profile, plasma levels of thiobarbituric acid reactive substances (TBARS, biomarkers of oxidative damage), fluorescent AGEs (biomarkers of advanced glycation), and paraoxonase 1 (PON1) activity (antioxidant enzyme). The activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver and kidneys were also investigated. RESULTS: Siolmatra brasiliensis extract had antiobesogenic effects; improved insulin sensitivity and glucose tolerance; decreased the total plasma cholesterol levels; decreased the levels of glycoxidative stress biomarkers, including AGEs (plasma, liver, kidneys) and TBARS (liver, kidneys); and also improved endogenous antioxidant defenses by increasing the activities of PON1 (plasma), SOD (kidneys), CAT (liver, kidneys), and GSH-Px (kidneys). CONCLUSION: This study expands on our knowledge about the pharmacological properties of S. brasiliensis and substantiates the potential of this plant species to be used as a complementary therapeutic agent to alleviate the metabolic dysfunctions resulting from dyslipidemia and glycoxidative stress.

Myrcia eriopus DC. (Myrtaceae) fruits, a new endemic Brazilian source of bioactive anthocyanins.

Myrcia eriopus DC. (Myrtaceae) is a native and endemic Brazilian species, and there is no information about its chemical composition. In our study, five different anthocyanins and two other phenolic compounds were described for the first time in M. eriopus fruits. Delphinidin 3-O-glucoside (1), cyanidin 3-O-glucoside (2), petunidin 3-O-glucoside (3), peonidin 3-O-glucoside (4), malvidin 3-O-glucoside (5), gallic acid (6) and myricetin (7) were identified by offline system RP-HPLC-DAD/ESI-QTOF-MS and compared to the scientific literature. Furthermore, the lyophilized powder of M. eriopus fruits showed a high anthocyanin content (1878.14 mg cy-3-glu eqv/100 g f.w.), with greater levels of compounds 1 and 3, and an antioxidant potential in DPPH and ABTS assays (EC50 2419 µg/mL and 339 µmol Trolox/g f.w.), results superior to other non-conventional Brazilian fruits. This first report about the chemical composition of M. eriopus fruit reveals the potential of this fruit as a new source of bioactive anthocyanins.

Application crude multienzyme extract from Aspergillus niger as a pretreatment for the extraction of essential oil from Croton argyrophyllus leaves.

Leaves of Croton argyrophyllus contain essential oil with promising active components for the development of drugs and botanical insecticides. In this study, we evaluated the enzymatic pretreatment process to increase the extraction of essential oil from fresh and dried leaves of C. argyrophyllus. Pretreatment was carried out using a crude multienzymatic extract obtained via solid-state fermentation of forage palm by Aspergillus niger, and the extraction was performed by hydrodistillation. A Doehlert matrix was used to optimize the enzymatic pretreatment variables temperature and enzymatic extract. The effect of pretreatment time was also investigated. At optimum experimental conditions, 41.34°C, 140 min, and 130.73 mL of enzyme in 369.27 mL of water, the essential oil yield from fresh leaves subjected to enzymatic pretreatment increased by 9.35% and that from dry leaves by 6.77%. Based on chromatographic analysis (GC-MS), no compound was degraded in the extraction process. Micromorphological analysis confirmed the rupture of the glandular trichomes, favoring essential oil release. Therefore, enzymatic pretreatment associated with hydrodistillation increased the essential oil yield and is a promising application to obtain essential oil for therapeutic purposes without altering its composition.

Acaricidal activity of essential oils of Cinnamomum zeylanicum and Eremanthus erythropappus, major compounds and cinnamyl acetate in Rhipicephalus microplus.

This study aimed to chemically characterize the essential oils (EOs) of Cinnamomum zeylanicum (cinnamon) and Eremanthus erythropappus (candeia) and evaluate their acaricidal activity, together with that of their major compounds and cinnamyl acetate derivative, against Rhipicephalus microplus. Essential oil compounds were identified through gas chromatography. The larval packet test (LPT) at concentrations ranging from 0.31 to 10.0 mg/mL and the adult immersion test (AIT) at concentrations between 2.5 and 60.0 mg/mL were performed. (E)-cinnamaldehyde and α-bisabolol were the major compounds in cinnamon (86.93%) and candeia (78.41%) EOs, respectively. In the LPT, the EOs of cinnamon and candeia and the compounds (E)-cinnamaldehyde, α-bisabolol and cinnamyl acetate resulted in 100% mortality at concentrations of 2.5, 2.5, 5.0, 10.0 and 10.0 mg/mL respectively. In the AIT, percentage control values > 95% were observed for cinnamon and candeia EOs, (E)-cinnamaldehyde and α-bisabolol at the concentrations of 5.0, 60.0, 20.0, and 20.0 mg/mL, respectively, whereas cinnamyl acetate showed low activity. We conclude that EOs and their compounds showed high acaricidal activity, whereas the acetylated derivative of (E)-cinnamaldehyde presented less acaricidal activity on R. microplus engorged females.

Antileishmanial activity of the essential oils of Myrcia ovata Cambess. and Eremanthus erythropappus (DC) McLeisch leads to parasite mitochondrial damage.

Leishmania amazonensis is a species causative of cutaneous and anergic diffuse cutaneous leishmaniasis, treatment-resistant form, in the New World. Plants essential oils exhibit great potential as microbicide agents. We described the composition of the essential oils of two plants native from Brazil, Myrcia ovata, with geranial and neral as major constituents, and Eremanthus erythropappus, with α-bisabolol. In vitro effects of these essential oils on L. amazonensis promastigotes growth and ultrastructure were analysed as well as their cytotoxicity to murine macrophages. Both oils were highly active with IC50/96 h of 8.69 and 9.53 µg/mL for M. ovata and E. erythropappus against promastigotes and caused ultrastructural alterations including mitochondrial enlargement. Cytotoxicity for murine macrophages varied with the oil concentrations. The IC50 low values of both M. ovata and E. erythropappus oils against L. amazonensis and their relative low cytotoxicity to mammal host cells support their potential use against cutaneous leishmaniasis.

Acaricidal activity of essential oils of Cinnamomum zeylanicum and Eremanthus erythropappus, major compounds and cinnamyl acetate in Rhipicephalus microplus / Atividade acaricida dos óleos essenciais de Cinnamomum zeylanicum e Eremanthus erythropappus, compostos majoritários e acetato de cinamila sobre Rhipicephalus microplus

Abstract This study aimed to chemically characterize the essential oils (EOs) of Cinnamomum zeylanicum (cinnamon) and Eremanthus erythropappus (candeia) and evaluate their acaricidal activity, together with that of their major compounds and cinnamyl acetate derivative, against Rhipicephalus microplus. Essential oil compounds were identified through gas chromatography. The larval packet test (LPT) at concentrations ranging from 0.31 to 10.0 mg/mL and the adult immersion test (AIT) at concentrations between 2.5 and 60.0 mg/mL were performed. (E)-cinnamaldehyde and α-bisabolol were the major compounds in cinnamon (86.93%) and candeia (78.41%) EOs, respectively. In the LPT, the EOs of cinnamon and candeia and the compounds (E)-cinnamaldehyde, α-bisabolol and cinnamyl acetate resulted in 100% mortality at concentrations of 2.5, 2.5, 5.0, 10.0 and 10.0 mg/mL respectively. In the AIT, percentage control values > 95% were observed for cinnamon and candeia EOs, (E)-cinnamaldehyde and α-bisabolol at the concentrations of 5.0, 60.0, 20.0, and 20.0 mg/mL, respectively, whereas cinnamyl acetate showed low activity. We conclude that EOs and their compounds showed high acaricidal activity, whereas the acetylated derivative of (E)-cinnamaldehyde presented less acaricidal activity on R. microplus engorged females.

Resumo Este estudo teve como objetivo caracterizar quimicamente os óleos essenciais (OE) de Cinnamomum zeylanicum (canela) e Eremanthus erythropappus (candeia) e avaliar sua atividade acaricida, juntamente com a de seus principais compostos e do derivado de acetato de cinamila, sobre Rhipicephalus microplus. Os compostos do óleo essencial foram identificados por cromatografia gasosa. Foram realizados o Teste de Pacote de Larvas (TPL), em concentrações variando de 0,31 a 10,0 mg/mL, e o Teste de Imersão de Adultos (TIA), em concentrações entre 2,5 e 60,0 mg/mL. (E)-cinnamaldeído e α-bisabolol foram os principais compostos nos OE da canela (86,93%) e da candeia (78,41%), respectivamente. No TPL, os OEs de canela e candeia, e os compostos (E)-cinnamaldeído, α-bisabolol e acetato de cinamila resultaram em 100% de mortalidade nas concentrações de 2,5, 2,5, 5,0, 10,0 e 10,0 mg/mL, respectivamente. No TIA, valores percentuais de controle >95% foram observados para OE de canela e candeia, (E)-cinnamaldeído e α-bisabolol nas concentrações de 5,0, 60,0, 20,0 e 20,0 mg/mL, respectivamente, enquanto o acetato de cinamila apresentou baixa atividade. Conclui-se que os OEs e seus compostos apresentaram alta atividade acaricida, enquanto o derivado acetilado do (E)-cinnamaldeído apresentou menor atividade acaricida em fêmeas ingurgitadas de R. microplus.

The effect of the biflavonoid 2″,3″-dihydroochnaflavone on Trypanosoma cruzi Y strain.

Trypanosoma cruzi is the causative agent of Chagas disease which affects 8 million people in Latin America. The parasite possesses high capacity to evade host immune system and the available drugs to treat Chagas disease present low efficacy combined to serious side effects to patients. Therefore, the identification of alternative therapeutics is essential. Brazilian flora exhibits an immense diversity of metabolites with great potential to be developed into new drugs. We investigated the action of 2″,3″-dihydroochnaflavone a biflavonoid extracted from Luxemburgia nobilis Eichler ex Engl. (Ochnaceae) against T. cruzi (Y strain). Our experiments showed that this compound is effective against parasite epimastigote forms, presenting IC50 value of (2.5 ± 0.1) µM after 96 h of treatment. Ultrastructure alterations were also detected in treated epimastigotes especially mitochondrial enlargement at the kinetoplast region. At the concentration of 30 µM, the compound killed (61.6 ± 3.37)% of the parasite in its amastigote form. In addition, at the same concentration, the compound killed all trypamastigotes growing within murine macrophages after 7-9 days of infection. Nonetheless, the biflavonoid concentrations were harmless to murine enriched population of lymphocytes and peritoneal macrophages. These results indicate that 2″,3″- dihydroochnaflavone presents activity against T. cruzi.

Acaricidal activity of Acmella oleracea (Asteraceae) extract against Rhipicephalus microplus: What is the influence of spilanthol?

The present study was carried out to evaluate and compare the acaricidal activity of different fractions of Acmella oleracea methanolic extract, containing 0.0 % (F1), 24.5 % (F2), 48.0 % (F3) and 100 % (F4) of spilanthol, on unfed larvae and engorged females from the same Rhipicephalus microplus population. To obtain these fractions, the crude extract was subjected to different extraction procedures using increasingly polarized solvents to isolate the spilanthol compound. The Larval Packet Test was used to evaluate acaricidal activity in unfed larvae at concentrations ranging from 0.2 to 25.0 mg/mL, while for engorged females, the Adult Immersion Test was performed at concentrations from 3.1 to 25.0 mg/mL. The F1 fraction showed no activity on unfed larvae, while a control percentage of 44.6 % was observed at a concentration of 25.0 mg/mL for engorged females. For unfed larvae, the F2 fraction resulted in 95.7 % mortality at a concentration of 1.6 mg/mL, with a control percentage of 92.7 % for engorged females at a concentration of 12.5 mg/mL. Fractions F3 and F4 had similar activity against unfed larvae, with mortality >84.0 % from the concentration of 0.8 mg/mL. This similarity between the fractions was also observed for engorged females from a concentration of 12.5 mg/mL, resulting a control percentage >94.0 %. These results demonstrate that the presence of spilanthol is an important factor for the acaricidal activity of A. oleracea extract. Fraction extracts with 24.5, 48 and 100 % of spilanthol have similar acaricidal activity on R. microplus.

Encapsulation of the black pepper (Piper nigrum L.) essential oil by lactoferrin-sodium alginate complex coacervates: Structural characterization and simulated gastrointestinal conditions.

Black pepper essential oil (EO) was encapsulated by complex coacervation with lactoferrin and sodium alginate using transglutaminase as a cross-linking agent. The encapsulation efficiency varied from 31.66 to 84.48%. Chemical and morphological characteristics suggest that the EO was encapsulated in a lactoferrin/sodium alginate shell. The chemical composition of the encapsulated EO was identified by gas chromatography (GC) and nuclear magnetic resonance (NMR). The GC and NMR analyses indicated good core protection with the materials used. The stability of the black pepper EO capsules under in vitro digestion was evaluated. Theses capsules demonstrated the low release of the EO during gastric digestion and higher release in intestinal digestion. These results suggest that these capsules can be used to transport active ingredients and that they are resistant to oral and gastric conditions that were tested in vitro.

Study on the Antinociceptive Activity and Mechanism of Action of Isolated Saponins from Siolmatra brasiliensis (Cogn.) Baill.

Infusions of roots of Siolmatra brasiliensis (Cogn.) Baill, ("taiuiá", "cipó-tauá") are used for toothache pain and ulcers. We aimed to study the antinociceptive effects and identify the possible mechanism of action of this plant and its isolated substances (cayaponoside A1, cayaponoside B4, cayaponoside D, and siolmatroside I). Hydroethanol extract (HE), ethyl acetate fraction (EtOAc), and isolated saponins were evaluated in chemical and thermal models of pain in mice. Animals were orally pretreated and evaluated in the capsaicin- or glutamate-induced licking and in the hot plate tests. The antinociceptive mechanism of action was evaluated using the hot plate test with the following pretreatments: Atropine (cholinergic antagonist), naloxone (opioid antagonist), or L-NAME (nitric oxide synthase inhibitor). All extracts and isolated saponins increased the area under the curve in the hot plate test. Tested substances induced a higher effect than the morphine-treated group. Our data suggest that stems of S. brasiliensis and their isolated substances present antinociceptive effects. Cholinergic and opioidergic pathways seem to be involved in their mechanism of action. Taken together our data corroborate the traditional use of the plant and expands the information regarding its use.

Microencapsulation of sacha inchi oil (Plukenetia volubilis L.) using complex coacervation: Formation and structural characterization.

In this study, sacha inchi oil (SIO) (Plukenetia volubilis L.) was microencapsulated via complex coacervation of ovalbumin (OVA) and sodium alginate (AL), and the microcapsule properties were characterized. The omega-3 content in the SIO was evaluated after in vitro gastric simulation and microencapsulation. The coacervate complex between OVA and AL was evaluated based on electrostatic interactions and developed for use as a wall material via the SIO microencapsulation process. The best mass ratio for the biopolymers (OVA:AL) was 4:1 at pH 3.8, and the complex exhibited a thermal resistance at 189.86 °C. The SIO microcapsules showed a high encapsulation efficiency of approximately 94.12% in the ratio (OVA:AL) of 1:1. Furthermore, microencapsulated SIO presented resistance under gastric conditions with a low release of acyl (ω-3) units. These results demonstrate that it is possible to use OVA:AL as encapsulating agents to protect bioactive compounds and to improve the thermal behavior of microcapsules.

Antibiofilm activity of the essential oil of citronella (Cymbopogon nardus) and its major component, geraniol, on the bacterial biofilms of Staphylococcus aureus.

Medicinal plants with antimicrobial action have been investigated for uses against biofilms, among which, Cymbopogon nardus, citronella, stands out as a promising species. The present study aims to evaluate the antimicrobial and antibiofilm action of the essential oil of C. nardus (EOCN) and geraniol on Gram-negative and positive bacteria from the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration and inhibition of biofilms. In the results, the EOCN produced a 41 mm halo on S. aureus, which was susceptible with MIC values of 0.5 and 0.25 mg/mL for the EOCN and geraniol respectively, both with bactericidal effect. The antibiofilm action was confirmed, the EOCN and geraniol reduced the biofilm biomass of S. aureus up to 100% between 0.5 and 4 mg/mL concentrations. The reduction of cell viability was 0.25 and 1 mg/mL, of EOCN and geraniol, respectively. EOCN and geraniol were shown to be promising antibiotic against S. aureus.

Physicochemical, thermal and rheological properties of synthesized carboxymethyl tara gum (Caesalpinia spinosa).

Carboxymethyl tara gum (CMTG) was synthesized from the reaction between tara gum (TG) and monochloroacetic acid (MCA) in the presence of sodium hydroxide. The modification reaction was optimized in terms of the MCA/NaOH ratio, reaction time and temperature evaluated for degree of substitution (DS). The etherification was confirmed by FTIR and 13C NMR spectroscopy, and it was characterized by different analyses. After carboxymethylation, CMTG showed new bonds at 1592, 1413 and 1320 cm-1 by FTIR and a new peak at δ = 178 ppm by 13C NMR in response to the insertion of the carbonyl group. The microscopy showed higher degradation on the surface of the CMTG particles, and XRD indicated low crystallinity of the CMTG. Static light scattering demonstrated a reduction in the molar mass of tara gum after carboxymethylation. Thermal analysis (TGA and DSC) revealed a lower thermal stability of carboxymethylated gum compared to that of unmodified gum. Despite the insertion of negative charges demonstrated by the potential-zeta, CMTG and TG presented pseudoplastic behavior according to the rheological analyses, and CMTG presented lower viscosity at the concentrations that were studied.

Dammarane-type triterpenoids from the stem of Ziziphus glaziovii Warm. (Rhamnaceae).

Seven undescribed dammarane-type triterpenoids, together with ten known compounds, were isolated from the stems of Ziziphus glaziovii Warm (= Sarcomphalus glaziovii (Warm.) Hauenschild). The structures were fully assigned by means of uni- and bidimensional NMR and HR-ESI-MS experiments. Extract, fractions and also isolated compounds were evaluated for their antibacterial (against Bacillus subtilis and Aliivibrio fischeri), cytotoxic (against PC-3 and HT-29 human cancer cell lines), anthelmintic (against Caenorhabditis elegans) and antifungal (against Septoria triciti, Botrytis cinerea and Phytopthoria infestans) activities. The methanolic crude extract exhibited substantial antibacterial and cytotoxic activity. The known triterpenes epigouanic acid and alphitolic acid were the most active compounds against B. subtilis, with IC50 of 12 and 22 µM, respectively. The isolated compounds presented up to a concentration of 10 µM none or only weak effects in the cytotoxicity assays. No anthelminthic and antifungal activities were observed.

Antimycobacterial and Nitric Oxide Production Inhibitory Activities of Triterpenes and Alkaloids from Psychotria nuda (Cham. & Schltdl.) Wawra.

A phytochemical study of leaves and twigs of Psychotria nuda resulted in 19 compounds, including five indole alkaloids, N,N,N-trimethyltryptamine, lyaloside, strictosamide, strictosidine, and 5α-carboxystrictosidine; two flavonolignans, cinchonain Ia and cinchonain Ib; an iridoid, roseoside; a sugar, lawsofructose; a coumarin, scopoletin; a diterpene, phytol; three triterpenes, pomolic acid, spinosic acid, and rotungenic acid; and five steroids, sitosterol, stigmasterol, campesterol, ß-sitosterol-3-O-ß-d-glucoside, and ß-stigmasterol-3-O-ß-d-glucoside. Some compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis and their ability to inhibit NO production by macrophages stimulated by lipopolysaccharide (LPS). The compounds pomolic acid, spinosic acid, strictosidine, and 5α-carboxystrictosidine displayed antimycobacterial activity with minimum inhibitory concentrations ranging from 7.1 to 19.2 µg/mL. These compounds showed promising inhibitory activity against NO production (IC50 3.22 to 25.5 µg/mL). 5α-carboxystrictosidine did not show cytotoxicity against macrophages RAW264.7 up to a concentration of 100 µg/mL. With the exception of strictosamide, this is the first report of the occurrence of these substances in P. nuda.

New compounds of Siolmatra brasiliensis and inhibition of in vitro protein glycation damage.

Twenty compounds were isolated from the hydroethanolic extract of the stems of Siolmatra brasiliensis, five flavonoids, two lignans, one glucosyl phytosterol, seven nor-cucurbitacins, one new phenolic derivative named siolmatrin (1) and four new dammarane-type saponins named siolmatrosides II-V (2-5), the structures of the compounds were assigned by means of 1D and 2D NMR experiments and HRESIMS of the natural compounds and some acetyl derivatives. The effects of the crude hydroethanolic extract (SbExt) and the ethyl acetate fraction (SbEtAc) of Siolmatra brasiliensis stems on the formation of advanced glycation end-products (AGEs) were also investigated. In the in vitro model system of protein glycation using bovine serum albumin (BSA) and glucose, addition of SbExt or SbEtAc inhibited the formation of fluorescent AGEs, in parallel to minor levels of fructosamine (SbEtAc) and markers of tyrosine and tryptophan oxidation (SbExt and SbEtAc). Protein crosslinking, which represents changes of late stages of protein glycation, was reduced in the presence of SbExt and SbEtAc. Siolmatra brasiliensis stems seem to be a promising source of compounds having ability to prevent glycoxidation changes, arising as an interesting option to be studied as a complementary therapy for complications of diabetes.