Piper tectoniifolium Kunth: A New Natural Source of the Bioactive Neolignan (-)-Grandisin.

The Piper species are a recognized botanical source of a broad structural diversity of lignans and its derivatives. For the first time, Piper tectoniifolium Kunth is presented as a promising natural source of the bioactive (-)-grandisin. Phytochemical analyses of extracts from its leaves, branches and inflorescences showed the presence of the target compound in large amounts, with leaf extracts found to contain up to 52.78% in its composition. A new HPLC-DAD-UV method was developed and validated to be selective for the identification of (-)-grandisin being sensitive, linear, precise, exact, robust and with a recovery above 90%. The absolute configuration of the molecule was determined by X-ray diffraction. Despite the identification of several enantiomers in plant extracts, the major isolated substance was characterized to be the (-)-grandisin enantiomer. In vascular reactivity tests, it was shown that the grandisin purified from botanical extracts presented an endothelium-dependent vasorelaxant effect with an IC50 of 9.8 ± 1.22 µM and around 80% relaxation at 30 µM. These results suggest that P. tectoniifolium has the potential to serve as a renewable source of grandisin on a large scale and the potential to serve as template for development of new drugs for vascular diseases with emphasis on disorders related to endothelial disfunction.

Medicinal Plants as Efficacious Agents for Diabetic Foot Ulcers: A Systematic Review of Clinical Studies.

A diabetic foot ulcer (DFU) is a chronic, nonhealing wound that occurs in approximately 15% to 25% of patients with diabetes, and amputation is necessary in approximately 5% to 24% of these patients. Medicinal plants have demonstrated promising wound healing activities in animal models of DFUs as well as in clinical studies. These plants, which are described as medicinal in different regions of the world, are not considered to be standard medicinal treatments in Western medicine at this time. Some medicinal products, such as bromelain-an herbal protease currently used for enzymatic debridement of wounds-have been obtained from plants, showing the important role of these natural products as sources of wound healing agents. This paper aims to review clinical studies on the effects of medicinal plants in patients with DFUs based on the improvement of local and systemic parameters related to wound healing. Electronic databases including PubMed, Scopus, and Cochrane Library were searched for studies from inception through May 2019 using the keywords "diabetic foot ulcer" and "plant," "phytochemical," "extract," or "herb." Inclusion criteria were controlled or before-after clinical studies with English-language full-text in which topical or systemic herbal preparations for DFUs were evaluated by considering outcomes such as reduction of wound healing time and wound area, markers of inflammation and oxidative stress, and number of cases requiring amputation. Studies on non-herbal materials and human studies other than clinical trials were excluded. Fourteen studies were included in the present review. Herbal medicines were administered as add-on therapy to standard wound care in the form of topical (cream, gel, oil) or systemic (capsule, decoction, injection) preparations. Parameters such as ulcer width and depth, phagocytic function, tumor necrosis factor α level, epithelialization, vascularization, and wound closure were evaluated in clinical trials, several of which were significantly improved in patients compared with their baseline values or control group. Per the studies included in this review, medicinal plants can be recommended as promising adjuvant therapies to conventional wound care to accelerate wound healing in patients with DFUs.

Microvascular Effects of Echinodorus grandiflorus on Cardiovascular Disorders.

Echinodorus grandiflorus is a semiaquatic plant native to Brazil and belongs to the Alismataceae family. Infusion preparations of the leaves of this plant are often used due to its diuretic, blood pressure lowering, and anti-inflammatory properties. Our aim was to investigate the effects of chronic treatment with the crude hydroalcoholic extract of E. grandiflorus on central and peripheral microvascular changes induced in a model of hypertension and diabetes. The hemodynamic and microvascular effects of E. grandiflorus extract (50, 100, or 200 mg/kg/day for 28 days) or the isolated major diterpene from E. grandiflorus (3 to 10 mg/kg i. v.) were evaluated in spontaneously hypertensive rats using tail plethysmography and intravital fluorescence videomicroscopy, respectively, and were compared to vehicle-treated normotensive Wistar-Kyoto rats. We also investigated the protective effects of chronic treatment with E. grandiflorus (100 mg/kg/day) in brain capillary density and leukocyte-endothelium interactions on the brain vessels of DM-spontaneously (DM: diabetes mellitus) hypertensive rats. Chronically treating spontaneously hypertensive rats with increasing doses of crude hydroalcoholic E. grandiflorus extract resulted in significant dose-dependent reductions in systolic blood pressure and an anti-inflammatory effect on the brain microcirculation of DM-spontaneously hypertensive rat animals. Using laser speckle contrast imaging, we observed that intravenous administration of the major isolated clerodane diterpene metabolite (1 - 10 mg/kg) increased microvascular blood flow by 25% in spontaneously hypertensive rat skeletal muscle. The results of this study show that E. grandiflorus extracts can be useful in the prevention and reduction of microcirculatory damage in arterial hypertension and other diseases that involve microvascular dysfunction.

Aloysia citrodora Paláu (Lemon verbena): A review of phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Aloysia citrodora Paláu (Lippia citriodora Kunth), commonly known as "lemon verbena" is a medicinal plant native to South America, North Africa, and South of Europe which is used by native people for several indications such as diarrhea, flatulence, insomnia, and rheumatism. AIM OF THE REVIEW: Despite the wide biological activities of lemon verbena, there is no current review summarizing medicinal properties of the plant; thus, this paper aims to discuss current state of the art regarding the phytochemistry, pharmacology, and therapeutic applications of A. citrodora considering in vitro, in vivo, and clinical studies. MATERIALS AND METHODS: Electronic databases including PubMed, Scifinder, Cochrane library, Scopus, and Science direct were searched with the scientific name of the plant and its synonyms, as well as the common name. All studies on the ethnobotany, phytochemistry, pharmacology, and clinical application of the plant until October 2017 were included in this review. RESULTS: Despite the few number of studies on the ethnopharmacology of the plant, A. citrodora is widely assessed regarding its phytochemistry and biological activities. Neral and geranial are the main ingredients of the essential oil; whereas verbascoside is the most significant component of the extract. Biological activities such as antioxidant, anxiolytic, neuroprotective, anticancer, anesthetic, antimicrobial, and sedative effects are proved in cell cultures, as well as animal studies. CONCLUSIONS: Several pharmacological activities have been reported for A. citrodora; however, the plant is not fully assessed regarding its safety and efficacy in human. Future well-designed human studies are essential to confirm the therapeutic benefits of this plant in clinical settings.

HSCCC separation and enantiomeric distribution of key volatile constituents of Piper claussenianum (Miq.) C. DC. (Piperaceae).

High Speed Countercurrent Chromatography (HSCCC) technique was used for the preparative isolation of the major leishmanicidal compounds from the essential oils of Piper claussenianum species in Brazil. The essential oils from inflorescences of P. claussenianum were analyzed by GC-FID and GC-MS. The enantiomeric ratio of the major constituents of the P. claussenianum essential oils were determined using a Rt-DEXsm chiral capillary column by GC-FID analysis. It was found an enantiomeric excess of (+)-(E)-nerolidol in the leaves, and (+)-linalool and (+)-(E)-nerolidol in the inflorescences essential oil. The major volatile terpenes alcohols were isolated in preparative scale from inflorescences: linalool (320.0 mg) and nerolidol (95.0 mg) in high purity level. The HSCCC, a support-free liquid-liquid partition chromatographic technique, proved to be an effective and useful method for fast isolation and purification of hydrophobic and similarly structured bioactive components from essential oils of Piper species.

Echinodorus grandiflorus: Ethnobotanical, phytochemical and pharmacological overview of a medicinal plant used in Brazil.

Echinodorus grandiflorus (Cham. & Schltdl.) Micheli is a native Brazilian species used in traditional practices for the treatment of several conditions such as inflammatory diseases, arthritis and hypertension. Through a systematic review of the accumulated knowledge about the species E. grandiflorus, the botanical, phytochemistry, ethnobotanical and pharmacological properties of this medicinal plant demonstrates its potential to naturally provide anti-inflammatory and anti-oxidant with a special emphasis on anti-hypertensive and cardioprotective effects. The body of literature reports that the chemical composition of crude E. grandiflorus extracts are notably composed of diterpenoids and flavonoids metabolites. Pharmacological studies have shown that oral treatments using the hydroalcoholic extracts of leaves from this plant has a significant anti-inflammatory, anti-hypertensive, diuretic and cardioprotective effects in rats with no toxicity. The holistic activities of complex extracts are corroborated by the individuals mechanisms of action, as well as, synergistic benefits attributed to the isolated chemical major constituents in this species. In light of the serious health concerns ascribed, it is important to investigate medicinal plant species with histories of traditional use for circulatory problems to meet the growing demands by scientifically validating their use and safety.

Larvicidal activity of Ottonia anisum metabolites against Aedes aegypti: A potential natural alternative source for mosquito vector control in Brazil.

BACKGROUND & OBJECTIVES: Aedes aegypti mosquito is the principal vector of the viruses responsible for urban yellow fever, dengue, dengue haemorrhagic fever, as well as Zika and chikungunya in Brazil. The present study was aimed to investigate the insecticidal potential of the extract and fractions of Ottonia anisum, along with special metabolites isolated from it, as natural alternatives against larvae (L3) of Ae. aegypti, vector of potentially deadly tropical infections in Brazil. METHODS: The plant species O. anisum was collected in March 2015, at Xerιm area, in Rio de Janeiro City, Brazil. Crude extracts and the isolated pure compounds were screened for toxicity against Ae. aegypti larvae (L3). Bioassays were performed on 20 larvae (L3) of Ae. aegypti in triplicate. The samples were dissolved in a mixture of acetone and DMSO at final concentrations of 1-200 µg/ml. The toxicity of the solutions was evaluated towards the growth and development of Ae. aegypti larvae till emergence of adults. RESULTS: The crude hexane extract showed 100% larval mortality 24 h after treatment at a concentration of 200 µg/ml. The bioassays using 1-butyl-3,4-methylenedioxybenzene revealed 100% mortality among L3 larvae, 24 h afterthe treatment at a concentration of 30 µg/ml, the LC recorded was 1.6 µg/ml. At concentration of 10 µg/ml, the L3 larval mortality recorded was 92%. INTERPRETATION & CONCLUSION: The metabolite 1-butyl-3,4-methylenedioxybenzene showed potent toxicity against Ae. aegypti larvae. This arylbutanoid agent could be used as a natural alternative adjuvant pesticide, in new compositions that would be environmentally safer.

Local Anesthetic Activity from Extracts, Fractions and Pure Compounds from the Roots of Ottonia anisum Spreng. (Piperaceae).

Piperaceae species can be found worldwide in tropical and subtropical areas and many of them have been used for centuries in traditional folk medicine and in culinary. In Brazil, species of Piperaceae are commonly used in some communities as local anesthetic and analgesic. Countrified communities have known some species of the genus Ottonia as "anestesia" and it is a common habit of chewing leaves and roots of Ottonia species to relief toothache. The purpose of this study is to report our findings on new molecules entities obtained from the roots of Ottonia anisum Spreng, in which local anesthetic activity (sensory blockage) is demonstrated for the first time in vivo guinea pig model. Phytochemical investigation led to the isolation of three amides (pipercallosidine, piperine and valeramide) and in an enriched mixture of seven amides (valeramide, 4,5-dihydropiperlonguminine, N-isobutil-6-piperonil-2-hexenamide, piperovatine, dihydropipercallosidine, pipercallosidine and pipercallpsine). Our findings demonstrated the anesthetic potential for the methanolic extract from roots, its n-hexane partition and amides from O. anisum and it is in agreement with ethnobotanical survey.

Aristolactams from roots of Ottonia anisum (Piperaceae).

The Piperaceae species are known worldwide for its medicinal properties and its chemical compounds. In Brazil, many species of this family are distributed mainly in Amazon Region and in the Atlantic Forest. The genus Ottonia is known as source of amides, flavonoids, arilpropanoids and terpenes with record biological activities. Six aristolactams, including, aristolactam BII, piperolactam C, goniothalactam, stigmalactam, aristolactam AII and aristolactam BIII were isolated from roots of this species. GC-MS, 1H NMR and NOESY techniques were used to characterize these compounds. This is the first report about the occurrence of aristolactams in the Ottonia anisum Sprengel.

Chemistry and biological activity of essential oils from Piper claussenianum (Piperaceae).

Analyses of essential oils obtained from fresh and dried leaves and inflorescences of Piper clausenianum were performed using GC-FID, GC-MS and NMR techniques. Forty compounds were detected for these four oils with the total of identified constituents ranging from 88.7% for the dried inflorescences to 97.7% for the dried leaves. Sesquiterpenes were the main constituents in the volatile fraction from leaves with a high percentage of (E)-nerolidol (up to 83%). However, monoterpenes were identified in greater amount in the inflorescences, with linalool percentages from 50% up. The essential oils from fresh leaves and inflorescences were submitted to anti-parasitic activity against a strain of Leishmania amazonensis. Both samples showed biological activity, but the essential oil from P. claussenianum fresh leaves, which was rich in (E)-nerolidol, showed effective growth inhibition of L. amazonensis due to the high percentage of this metabolite in the mixture.

Caracterização de derivado arilbutanoídico em folhas e raízes de Ottonia anisum Sprengel / Characterization of an arylbutanoic derivative from leaves and roots of Ottonia anisum Sprengel

The family Piperaceae encompasses 5 genera, Piper, Peperomia, Pothomorphe, Ottonia and Sarcorhachis, and approximately 2,000 species widely distributed in the tropical and subtropical regions of the world. Most of the Ottonia species are native to Brazil and they are used in folk medicine as diuretic, salivating, and anaesthetic. Chemical studies of non-polar fractions from leaves and roots of Ottonia anisum Sprengel lead to the isolation of an arylbutanoic metabolite, the 1-butyl-3,4-methylenedioxybezene.

A família Piperaceae é formada por 5 gêneros, Piper, Peperomia, Pothomorphe, Ottonia e Sarcorhachis, com cerca de 2000 espécies de ampla distribuição nas regiões tropicais e subtropicais do mundo. Das 23 espécies descritas para o gênero Ottonia, a maioria é nativa do Brasil. Essas plantas são popularmente utilizadas no país como diuréticas, salivantes e anestésicas. O estudo químico dos extratos apolares de folhas e de raízes de Ottonia anisum Sprengel levou aoisolamento de um componente majoritário identifi cado como o derivado arilbutanoídico: 1-butil-3,4-metilenodioxibeneno.