Effects of olive oil and its minor phenolic constituents on obesity-induced cardiac metabolic changes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Isolation and evaluation of the antioxidant activity of phenolic constituents of the Garcinia brasiliensis epicarp

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A bacteriological study of hospital beds before and after disinfection with phenolic disinfectant

In hospitals, one of the ways to control microbial contamination is by disinfecting the furniture used by patients. This study's main objective was to evaluate the microbiological condition of hospital mattresses before and after such disinfection, in order to identify bacteria that are epidemiologically important in nosocomial infection, such as Staphylococcus aureus and Pseudomonas aeruginosa. RODAC plates with two different culture media were used to collect specimens. Patient beds were selected according to previously established criteria, and surface areas on the mattresses were chosen at random. From the total of 1 040 plate cultures from 52 mattresses, positive results were obtained from 500 of them (48.1%), 263 before disinfection and 237 after disinfection. Considering the selectivity of the culture media, the positivity rate was high. There were high prevalences of S. aureus both before and after mattress disinfection. The study results suggest that the usual disinfection procedures, instead of diminishing the number of microbes, merely displace them from one part of the mattress to another, and the number of microorganisms remains the same.

A new ent-kaurane diterpene from stems of Alibertia macrophylla K. Schum. (Rubiaceae)

Phytochemical investigations of the stems of a specimen of Alibertia macrophylla led to the isolation and characterization of the new diterpene ent-kaurane-2β,3α,16α-triol (1), along with triterpenes 2-8, iridoids 9-12, and phenolic acids 13-15. The structure of 1 was established based on spectroscopic studies (1H- and 13C-NMR, IR, and HR-ESI-MS). This is the first report of the isolation of a diterpene from the Alibertia genus in Rubiaceae. © 2007 Verlag Helvetica Chimica Acta AG.

A new antifungal phenolic glycoside derivative and iridoids and lignans from Alibertia sessilis (Vell.) K. Schum. (Rubiaceae)

A new antifungal phenolic glycoside, 3,4,5-trimethoxyphenyl-1-O-β-D- (5-O-syringoyl)-apiofuranosyl-(1→6)-β-D-glucopyranoside (1), together with four known iridoids, geniposidic acid (2), geniposide (3), 6α-hydroxygeniposide (4) and 6β-hydroxygeniposide (5); two lignans, (+)-lyoniresinol-3α-O-β-D-glucopyranoside (6), (-)-lyoniresinol- 3α-O-β-D-glucopyranoside (7); and two phenolic acids, chlorogenic (8) and salicylic acids (9) and D-manitol (10), were isolated from the ethanolic extract of the stems of Alibertia sessilis. Structures of 1 and of the known compounds were determined by spectroscopic analysis. All compounds isolated were evaluated for their antifungal activities against two phytopathogenic fungi strains Cladosporium cladosporioides and C. sphaerospermum by direct bioautography. ©2007 Sociedade Brasileira de Química.

Immunostimulatory effects of the phenolic compounds from lichens on nitric oxide and hydrogen peroxide production

The effects of isolated compounds from Brazilian lichens and their derivatives on H 2O 2 and NO production were studied using murine macrophages as a part of an attempt to understand their possible immunomodulatory properties. The compound cytotoxicity was studied using MTT assay. Macrophage stimulation was evaluated by the determination of NO (Griess assay) and H 2O 2 (horseradish peroxidase/phenol red) in supernatants of peritoneal macrophage cultures of Swiss mice. This research demonstrated stimulatory activities of some phenolic compounds isolated from lichens and their derivatives on H 2O 2 and NO production. Structure-activity relationships suggest several synthetic directions for further improvement of immunological activity.

Pharmacognostical evaluation of fruits of Solanum lycocarpum A. St.-Hill. (Solanaceae)

This study describes the chemical and physical-chemical profile of plant drug and ethanolic extract obtained from fruits of Solanum lycocarpum A. St.-Hill. (Solanaceae). The physical and chemical analysis involved the granulometry determination, non-compacted apparent density, loss on drying in oven and in infrared scale, pH, ash values and extractive values. The results determined the physical-chemical characteristics of the drug plant. It was also carried out the microbiological control of the plant drug. The preliminary phytochemical screening featured the presence of tannins, flavonoids and saponins in the plant drug and alkaloids and steroids in the ethanolic exctract. The solamargine and solasonine glycoalkaloids were identified through TLC and GC/ MS. The levels of total phenols and tannins were quantified in the extract (8.90% and 6,85% respectively). Such studies contribute to the chemical identification and quality control of S. lycocarpum fruits. © 2010 Phcog.net.

Dispersing carbon nanotubes in phenolic resin using an aqueous solution

The ability to control the carbon nanotube (CNT) dispersion in polymers is considered the key to most applications of nanotube/polymer composites. The carbon nanotube dispersion into water with different surfactants, as well as its incorporation into phenolic resins, was investigated. Ultrasonication of liquid suspensions was used to prepare stable dispersions. In order to evaluate the best surfactant to be used, light scattering and UV-Visible spectroscopy were employed. The structure of CNT reinforced of phenolic resin was analyzed in function of the concentration and type of surfactant, sonication power and time. It was also evaluated the influence in the dispersion by using the glass temperature transition properties being obtained by dynamic mechanical analyses and impact energy. © 2011 Sociedade Brasileira de Química.

Antioxidant capacity and total phenolic content of hydrothermally-treated 'Fuerte' avocado

Avocados possess high nutritional value with proven effectiveness in preventing cardiovascular diseases, attributed primarily to their unsaturated fatty acids content. This fruit is also rich in carotenoids and vitamins, particularly vitamin E. This work evaluates the antioxidant capacity and total phenolic content of hydrothermally-treated Fuerte avocado. Fruits were selected and hydrothermally treated at 45°C for 5, 10, 15 and 20 min. They were then stored in a refrigerator (10 ± 10°C and 90±5% relative humidity) and evaluated over a 15-day period. The total phenolic content increased up to the sixth day of storage, and decreased thereafter, without differences between the treatments. The percentage of antioxidant capacity of the control and the hydrothermally-treated samples for 5 and 10 min increased during storage. Untreated fruits showed the highest percentage of antioxidant capacity. However, the antioxidant capacity of avocado fruits subjected to these treatments declined starting on the twelfth day of storage, possibly due to the fruits' senescence. Hydrothermal treatments for 15 and 20 min delayed fruit senescence while the antioxidant capacity continued to increase up to the fifteenth day of storage. No significant correlation was found between antioxidant capacity and total phenolic content. The antioxidant capacity of ripe Fuerte avocado was higher than that of unripe or overripe avocado.

Extraction and quantification of phenolic acids and flavonols from Eugenia pyriformis using different solvents

The recovery of phenolic compounds of Eugenia pyriformis using different solvents was investigated in this study. The compounds were identified and quantified by reverse-phase high-performance liquid chromatography coupled with ultraviolet-visible diode-array detector (RP-HPLC-DAD/UV-vis). Absolute methanol was the most effective extraction agent of phenolic acids and flavonols (588.31 mg/Kg) from Eugenia pyriformis, although similar results (p ≤ 0.05) were observed using methanol/water (1:1 ratio). Our results clearly showed that higher contents of phenolic compounds were not obtained either with the most or the least polar solvents used. Several phenolic compounds were identified in the samples whereas gallic acid and quercetin were the major compounds recovered. © 2012 Association of Food Scientists & Technologists (India).

Dereplication of phenolic derivatives of qualea grandiflora and qualea cordata (vochysiaceae) using liquid chromatography coupled with ESI-QToF-MS/MS

A rational and selective method using on-line high-performance liquid chromatography (HPLC) coupled with electrospray quadrupole time-of-flight tandem mass spectrometry (ESI-QToF-MS/MS) was established for the dereplication of phenolic derivatives from Qualea grandiflora and Qualea cordata. The selection of the extracts was based on the antioxidant capacity measured by in vitro DPPH assay. The HPLC-ESI-QToF-MS/MS analysis was conducted by on-flow detection, using high-resolution mass/ratio ions as well as collision induced MS/MS experiments for selected protonated ions. The dereplication of the EtOAc fraction from the hydro alcohol extract from the stem bark of Q. grandiflora allowed the detection of the flavonoids: 3',4',5',5,6,7-hexahydroxy- 8 methylflavanone, 8-methyl-naringenine and 3',7-dimethoxy-8 methyl-4',5,7- trihydroxyflavanone, as well as a benzophenone derivatives: bis(4,6-dimethoxy-2- hydroxy-3-methylphenyl)- metanone, 3',4'-dimethoxy-8-methyl-5,6,7 trihydroxyflavanone, 7-methoxy-6-methyl- 3',4',5 trihydroxyflavanone, 6,8-dimethyl-3' methoxy-4',5,7 trihydroxyflavanone and 3',5'-dimethoxy-6,8- dimethyl-4',5,7 trihydroxyflavanone were detected in the EtOAc fraction from the hydro-alcohol extract from the leaves of Q. cordata. © 2013 Sociedade Brasileira de Química.

Characterization of flavonoids and phenolic acids in Myrcia bella cambess. Using FIA-ESI-IT-MSn and HPLC-PAD-ESI-IT-MS combined with NMR

The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-ITMS and FIA-ESI-IT-MSn method were developed for rapid identification of acylated flavonoids, flavonoid-O- glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts. © 2013 by the authors.

Chromatic characteristics and color-related phenolic composition of Brazilian young red wines made from the hybrid grape cultivar BRS Violeta (BRS Rúbea×IAC 1398-21)

The color characteristics and the phenolic composition related to color of young red wines elaborated with the hybrid grape cultivar BRS Violeta, developed for its adaptation to sub-tropical climates in Brazil, have been studied. These wines are characterized with a deep red-purplish color, reaching color intensity averaging 24 units. In spite of being young red wines elaborated with short maceration time, their content in total polyphenols was very high (around 3692. mg/L, as gallic acid equivalents), especially when compared to similar Vitis vinifera young red wines. Within polyphenols, anthocyanins predominated (around 2037. mg/L, as malvidin 3,5-diglucoside equivalents) and they were almost exclusively anthocyanidin 3,5-glucosides (ca. 97%), mainly built from B-ring tri-substituted anthocyanidins (delphinidin. >. petunidin. ≈. malvidin) and having high proportion of p-coumaroylated derivatives (ca. 28%) that confer higher stability. The content of hydroxycinnamic acid derivatives was also remarkable (ca. 95. mg/L, as caffeic acid equivalents) and unknown glucose derivatives of p-coumaric acid accounted for ca. 42% of total HCAD. Finally, these found flavonols were mainly based on myricetin whereas kaempferol derivatives were missing, their total content being within the ranges usually found for V. vinifera wines, but reaching their top values (ca. 91. mg/L, as quercetin 3-glucoside equivalents). All the aforementioned data suggest that Violeta wine could be considered an important dietary source of healthy polyphenols with a moderate alcoholic content (ca. 11.6%). © 2013 Elsevier Ltd.

Phenolic composition of the berry parts of hybrid grape cultivar BRS Violeta (BRS Rubea×IAC 1398-21) using HPLC-DAD-ESI-MS/MS

The grape is considered a major source of phenolic compounds when compared to other fruits and vegetables, however, there are many cultivars with distinct characteristics directly linked to phenolic profile. Thus, the present study aimed to identify and quantify, for the first time and in detail, the phenolic compounds present in the skin, flesh and seeds of BRS Violeta grape berry using combination of SPE methodologies and analytical HPLC-DAD-ESI-MS/MS. The study was extended to the different berry parts and the most important grape and wine phenolic families, and has revealed interesting features. Violeta grape has a very thick skin (46% of grape weight) that accumulated the most of grape phenolic compounds: great amount of anthocyanins (3930. mg/kg, as malvidin 3,5-diglucoside), together with also important amounts of flavonols (150. mg/kg, as quercetin 3-glucoside), hydroxycinnamic acid derivatives (HCAD; 120. mg/kg, as caftaric acid), and proanthocyanidins (670. mg/kg, as (+)-catechin); in contrast, it seems to be a low resveratrol producer. Violeta grape seeds accounted for similar proportions of low molecular weight flavan-3-ols (mainly monomers; 345. mg/kg, as (+)-catechin) and proanthocyanidins (480. mg/kg, as (+)-catechin). Violeta grape is a teinturier cultivar, but it only contained traces of anthocyanins and low amounts of all the other phenolic types in its red-colored flesh. The anthocyanin composition of Violeta grape was dominated by anthocyanidin 3,5-diglucosides (90%). Within flavonols, myricetin-type predominated and kaempferol-type was missing. In addition to expected hydroxycinnamoyl-tartaric acids, several isomeric esters of caffeic and p-coumaric acids with hexoses were tentatively identified, accounting for relevant proportions within the pool of HCAD. Although pending of further confirmation over successive vintages, the aforementioned results suggest that BRS Violeta grape cultivar could be considered an interesting candidate for the elaboration of highly colored and antioxidant-rich grape juices and wines. © 2013 Elsevier Ltd.

Pesquisa de atividade antitumoral e mutagênica in vitro de produtos naturais

Pós-graduação em Ciências Farmacêuticas - FCFAR