Geison M. Costa

In vitro antiherpes effects of a C‐glycosylflavonoid‐enriched fraction of Cecropia glaziovii Sneth*

Aims:  To investigate the in vitro antiherpes effects of the crude aqueous extract obtained from Cecropia glaziovii leaves and their related fractions, the n‐butanol fraction (n‐BuOH) and the C‐glycosylflavonoid‐enriched fraction (MeOHAMB), and to determine the viral multiplication step(s) upon which this C‐glycosylflavonoid‐enriched fraction acts.

Passiflora manicata (Juss.) aqueous leaf extract protects against reactive oxygen species and protein glycation in vitro and ex vivo models.

The leaf extracts of many species of genus Passiflora have been extensively investigated for their biological activities on several rat tissues, but mainly in the central nervous system and liver. They posses anxiolytic-like, sedative effects and antioxidant properties. Evidences suggest a key role of C-glycosylflavonoids in the biological activities of Passiflora extracts. Some species (such as P. manicata) of the genus are still poorly investigated for their chemical and biological activity. In this work, we aim to investigate both antioxidant and antiglycation properties of aqueous extract of P. manicata leaves (PMLE) in vitro and ex vivo models. Crude extract showed the C-glycosylflavonoid isovitexin as the major compound. Isoorientin and vitexin were also identified. In TRAP/TAR assay, PMLE showed a significant antioxidant activity. PMLE at concentrations of 10 and 100 μg mL⁻¹ significantly decreasing LDH leakage in rat liver slices. Antioxidant effect also was observed by decreased in oxidative damage markers in slices hence hydrogen peroxide was added as oxidative stress inductor. PMLE inhibited protein glycation at all concentrations tested. In summary, P. manicata aqueous leaf extract possess protective properties against reactive oxygen species and also protein glycation, and could be considered a new source of natural antioxidants.

An HPLC-DAD method to quantification of main phenolic compounds from leaves of Cecropia Species

An efficient and reproducible HPLC-DAD method was developed and validated for the simultaneous quantification of major compounds (chlorogenic acid, isoorientin, orientin and isovitexin) present in the leaves of two Cecropia species, C. glaziovii and C. pachystachya. From the leaves of C. glaziovii and C. pachystachya were isolated the C-glycosylflavones isoorientin and isovitexin and identified on both species chlorogenic acid (3-O-caffeoylquinic acid) and the O-glycosylflavonol isoquercitrin. The C-glycosylflavone orientin was isolated only from C. pachystachya. Chlorogenic acid was the major compound in both species (11.1 mg g-1 of extract of C. glaziovii and 27.2 mg g-1 of extract of C. pachystachya) and for the flavonoids quantified, isovitexin was the main C-glycosylflavonoid for C. glaziovii (4.6 mg g-1 of extract) and isoorientin the main one for C. pachystachya (17.3 mg g-1 of extract).

Phenolic Content and Antioxidant and Antimicrobial Properties of Fruits of Capsicum baccatum L. var. pendulum at Different Maturity Stages

The phenolic content, antioxidant potential, and antimicrobial activity of extracts of different parts of the fruit from Capsicum baccatum L. var. pendulum were investigated. The analysis of phenolic content was performed by the Folin-Ciocalteu method and reversed-phase high-performance liquid chromatography. The in vitro antioxidant activity was assessed by the total reactive antioxidant potential and total antioxidant reactivity index. The antioxidant activity was positively correlated with the amount of phenolics found in each sample. The ex vivo antioxidant potential was assessed using the rat liver slice model. The antimicrobial activity was screened using Gram-positive and Gram-negative bacteria and fungi. All the extracts revealed antioxidant activity and a weak antimicrobial activity.

VITEXIN DERIVATIVES AS CHEMICAL MARKERS IN THE DIFFERENTIATION OF THE CLOSELY RELATED SPECIES PASSIFLORA ALATA CURTIS AND PASSIFLORA QUADRANGULARIS LINN

The species of Passiflora are widely used in folk medicine as mild sedatives and tranquilizers. P. alata and P. quadrangularis are distributed throughout South America, with widespread occurrence in Brazil and Colombia. Due to the difficulty in making a botanical distinction between these species, especially in the absence of flowers and fruits, the use of chemical markers for these plants offer an alternative method of identification. This work describes the isolation and identification of the major flavonoids and saponins from the leaves of P. alata and P. quadrangularis, as well as rapid and efficient HPLC-DAD methods for comparison of these compounds in both species. Vitexin derivatives are proposed as chemical markers in the identification of P. alata and P. quadrangularis and the detection of adulterations in raw material.

Hepatoprotective effects and HSV-1 activity of the hydroethanolic extract of Cecropia glaziovii (embaúba-vermelha) against acyclovir-resistant strain

Context: Cecropia glaziovii Snethl. (Cecropiaceae), commonly known as “embaúba-vermelha”, is widely distributed throughout Latin America and has been reported in Brazilian folk medicine to treat cough, asthma, high blood pressure and inflammation. Objective: Investigate the hepatoprotective properties of crude hydroethanolic extract of C. glaziovii as well as its in vitro antioxidant and antiviral (HSV-1 acyclovir resistant strain) activities. Materials and methods: The hepatoprotective effect, the antioxidant properties and antiviral activity of crude hydroethanol extract (RCE40) from C. glaziovii leaves were evaluated by carbon-tetrachloride (CCl4)-induced hepatotoxicity, by TBARS (thiobarbituric acid reactive species) and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assays, respectively. Results: The RCE40 extract (20 mg/kg) inhibited lipid peroxidation on liver in post injury treatment and decreased serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In addition, in this protocol the RCE40 (20 mg/kg) enhanced the activity of hepatic enzymes (SOD/CAT) which are involved in combating reactive oxygen species (ROS), suggesting that it possesses the capacity to attenuate the CCl4-induced liver damage. Moreover the RCE40 (20 mg/kg) inhibited TBARS formation induced by several different inductors of oxidative stress showing significant antioxidant activity, including physiologically relevant concentration, as low as 2 µg/mL. Concerning antiviral activity, the RCE40 was effective against herpes simplex virus type 1 replication (29R acyclovir resistant strain) with EC50 = 40 µg/mL and selective index (SI) = 50. Discussion and conclusion: These results indicate that C. glaziovii could be a good source of antioxidant and anti-HSV-1 lead compounds.

Pharmacokinetics of Botanical Drugs and Plant Extracts

BACKGROUND Botanical drugs contain plant extracts, which are complex mixtures of compounds. As with conventional drugs, it is necessary to validate their efficacy and safety through preclinical and clinical studies. However, pharmacokinetic studies for active constituents or characteristic markers in botanical drugs are rare. OBJECTIVE The objective of this review was to investigate the global state of the art in pharmacokinetic studies of active ingredients present in plant extracts and botanical drugs. A review of pharmacokinetics studies of chemical constituents of plant extracts and botanical drugs was performed, with a total of 135 studies published between January 2004 and February 2015 available in recognized scientific databases. Botanical preparations were mainly found in the form of aqueous extracts of roots and rhizomes. The most widely studied species was Salvia miltiorrhiza Bunge, and the compound most frequently used as a pharmacokinetic marker was berberine. CONCLUSION Most studies were performed using the Sprague Dawley rat model, and the preparations were mainly administered orally in a single dose. Quantification of plasma concentrations of pharmacokinetic markers was performed mainly by liquid-liquid extraction, followed by high performance liquid chromatography coupled to mass spectrometry detector. In conclusion, in recent years there has been an increasing interest among researchers worldwide in the study of pharmacokinetics of bioactive compounds in botanical drugs and plant extracts, especially those from the Traditional Chinese Medicine.