Bifidobacteria in milk products: An overview of physiological and biochemical properties, exopolysaccharide production, selection criteria of milk products and health benefits

Research and commercial interest in the genus Bifidobacterium have increased in the last decade due to their potential health benefits in probiotic functional foods, especially in dairy products. However, cultivation of bifidobacteria in milk is a difficult task compared with that of conventional starters because milk is not a good medium for growth of these nutritionally fastidious microorganisms. Therefore, suitable strains of Bifidobacterium for dairy products should be selected based on their safety and technological and functional properties. There are a number of milk products containing bifidobacteria in the world market and the demand for new products is increasing with the awareness of the potential health benefits of the consumption of products blended with bifidobacteria. Some strains of Bifidobacterium, which produce exopolysaccharide, have been isolated and characterised. This review will discuss the general characteristics of bifidobacteria, exopolysaccharide production, the selection criteria of bacterial strains for milk products, current applications of bifidobacteria in milk products, and their nutritional and beneficial health properties.

Estrogens, brain and behavior: studies in fundamental neurobiology and observations related to women's health

Mechanisms and consequences of the effects of estrogen on the brain have been studied both at the fundamental level and with therapeutic applications in mind. Estrogenic hormones binding in particular neurons in a limbic-hypothalamic system and their effects on the electrophysiology and molecular biology of medial hypothalamic neurons were central in establishing the first circuit for a mammalian behavior, the female-typical mating behavior, lordosis. Notably, the ability of estradiol to facilitate transcription from six genes whose products are important for lordosis behavior proved that hormones can turn on genes in specific neurons at specific times, with sensible behavioral consequences. The use of a gene knockout for estrogen receptor alpha (ERalpha) revealed that homozygous mutant females simply would not do lordosis behavior and instead were extremely aggressive, thus identifying a specific gene as essential for a mammalian social behavior. In dramatic contrast, ERbeta knockout females can exhibit normal lordosis behavior. With the understanding, in considerable mechanistic detail, of how the behavior is produced, now we are also studying brain mechanisms for the biologically adaptive influences which constrain reproductive behavior. With respect to cold temperatures and other environmental or metabolic circumstances which are not consistent with successful reproduction, we are interested in thyroid hormone effects in the brain. Competitive relations between two types of transcription factors - thyroid hormone receptors and estrogen receptors have the potential of subserving the blocking effects of inappropriate environmental circumstances on female reproductive behaviors. TRs can compete with ERalpha both for DNA binding to consensus and physiological EREs and for nuclear coactivators. In the presence of both TRs and ERs, in transfection studies, thyroid hormone coadministration can reduce estrogen-stimulated transcription. These competitive relations apparently have behavioral consequences, as thyroid hormones will reduce lordosis, and a TRbeta gene knockout will increase it. In sum, we not only know several genes that participate in the selective control of this sex behavior, but also, for two genes, we know the causal routes. Estrogenic hormones are also the foci of widespread attention for their potential therapeutic effects improving, for example, certain aspects of mood and cognition. The former has an efficient animal analog, demonstrated by the positive effects of estrogen in the Porsolt forced swim test. The latter almost certainly depends upon trophic actions of estrogen on several fundamental features of nerve cell survival and growth. The hypothesis is raised that the synaptic effects of estrogens are secondary to the trophic actions of this type of hormone in the nucleus and nerve cell body.

Resolution and Absolute Configuration Assignment of a Natural Racemic Chromane from Peperomia obtusifolia (Piperaceae)

The resolution of the natural racemic chromane 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3 ``-methyl-2 ``-butenyl)-2-(4`-methyl-1`,3`-pentadienyl)-2H-1-benzopyran-6-carboxylic acid (1) isolated from the leaves of Peperomia obtusifolia has been accomplished using stereoselective HPLC. The absolute coil figuration of the resolved enantiomers was determined by the analysis of optical rotations and CD spectra. The finding of a racemic mixture instead of an enantiomerically pure metabolite raises questions about the final steps in the biosynthesis of this class of natural products, suggesting that the intramolecular chromane ring formation step may not be enzymatically controlled at all in P. obtusifolia. Chirality 21:799-801, 2009. (C) 2008 Wiley-Liss, Inc.

Cytotoxic and genotoxic effects of tambjamine D, an alkaloid isolated from the nudibranch Tambja eliora, on Chinese hamster lung fibroblasts

Marine organisms have been shown to be potential sources of bioactive compounds with pharmaceutical applications. Previous chemical investigation of the nudibranch Tambja eliora led to the isolation of the alkaloid tambjamine D. Tambjamines have been isolated from marine sources and belong to the family of 4-methoxypyrrolic-derived natural products, which display promising immunosuppressive and cytotoxic properties. Their ability to intercalate DNA and their pro-oxidant activity may be related to some of the biological effects of the 4-methoxypyrrolic alkaloids. The aim of the present investigation was to determine the cytotoxic, pro-oxidant and genotoxic properties of tambjamine D in V79 Chinese hamster lung fibroblast cells. Tambjamine D displayed a potent cytotoxic effect in V79 cells (IC50 1.2 mu g/mL) evaluated by the MTT assay. Based on the MTT result, V79 cells were treated with different concentrations of tambjamine D (0.6. 1.2. 2.4 and 4.8 mu g/mL). After 24 h, tambjamine D reduced the number of viable cells in a concentration-dependent way at all concentrations tested. assessed by the trypan blue dye exclusion test. The hemolytic assay showed that the cytotoxic activity of tambjamine D was not related to membrane disruption (EC50 > 100 mu g/mL). Tambjamine D increased the number of apoptotic cells in a concentration-dependent manner at all concentrations tested according to acridine orange/ethidium bromide staining, showing that the alkaloid cytotoxic effect was related to the induction of apoptosis. MTT reduction was stimulated by tambjamine D, which may indicate the generation of reactive oxygen species. Accordingly, treatment of cells with tambjamine D increased nitrite/nitrate at all concentrations and TBARS production starting at the concentration corresponding to the IC50. Tambjamine D, also, induced DNA strand breaks and increased the micronucleus cell frequency as evaluated by comet and micronucleus tests, respectively, at all concentrations evaluated. showing a genotoxic risk induced by tambjamine D. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Avaliação do potencial antiinflamatório, anticoagulante e hemorrágico de heparinóides presentes em "Artemia franciscana"

Heparan sulfate (HS) and Heparin (Hep) glycosaminoglycans (GAGs) are heterogeneous and highly charged polysaccharides. HS is structurally related to Hep but is much less substituted with sulfo groups than heparin and has a more varied structure (or sequence). Because of structural similiarities between these two polymers, they have been described together as heparinoids . Both chains bind a variety of proteins and mediate various physiologically important processes including, blood coagulation, cell adhesion and growth factor regulation. Heparinoids with structural characteristics similar to these described from HS and/or Hep from mammalian tissues have been isolated from different species of invertebrates, although only a few heparinoids from unusual sources have been characterized. The present study describes the presence of unusual heparinoids population from Artemia franciscana, isolated after proteolysis and fractionation by ion exchange resin and named, F-3.0M. The study model in vivo were hemostasis (rat tail scarification) and inflamatoty activity. The tests in vitro were used for coagulations assays (PT and APTT). The analyse of the heparinoids eluted with 3,0M NaCl showed electrophoretic migration in different buffer systems a single band with a behaviour intermediate between those of mammalian HEP and HS. The main products obtained from Artemia heparinoids after enzymatic degradation with heparitinases I and II from F. heparinum were N-sulphated disaccharides (∆U-GlcNS,6S/ ∆U,2S-GlcNS and ∆U-GlcNS) and N-acetylated disaccharides (∆U, GlcNAc). This heparinoid had a lower hemorrhagic effect (400μg/ml) when compared to unfractiionated heparins(25μg/ml).The results also suggest a negligible APTT activity of this heparinoid (62.2s). No action was observed on PT indicating that F-3.0M haven t action on the extrinsic pathway. The results showed that the fraction F- 3.0M have inhibitory effect on migration of leukocytes, 64.5% in the concentration of 10 μg/ml (P<0.001). The search for new heparin and/or heparan sulphates analogs devoid of anticoagulant activity is an atractive alternative and may open up a wide variety of new therapeutic applications

Estratégias de obtenção do corante do jambo vermelho (Syzygium malaccense) e avaliação de sua funcionalidade

The food industry is interested in natural products. Anthocyanins are phenolic antioxidants of great importance with health-relevant applications. Several studies have linked the intake of fruits and vegetables with reduced risk of chronic degenerative diseases because of its antioxidant properties. This study aimed to compare different strategies for obtaining natural pigments from red jambo (Syzygium malaccence) and analyze its functional potential. Two different strategies were studied: (1) solid-liquid extraction (SLE) in reactor with controlled parameters, (2) powder obtention. The investigation of the functional potential was conducted taking into account the total phenolic content (TPC), the antioxidant activity (AA), the total anthocyanins concentration (TA) and α-amylase and α-glucosidase inhibition. The best extracts obtained by SLE showed TPC of 174.15 mg GAE/100g, AA of 3.56 μmol Trolox eq/g and TA of 133.59 mg cyd-3-glu/100 g. The best results for the second strategy were TPC of 1024.22 mg GAE/100 g, AA of 29.03 μmol Trolox eq/g and TA of 1193.41 mg cyd-3- glu/100 g. It was observed moderate amylase inhibition (26.30%) and high glucosidase inhibitory activity (97.47%). Skin extracts showed, in general, superior results when compared to whole red jambo, with superior values for dehydrated products. Based on our result, red jambo can be considered as a rich source of phenolic antioxidants, as well on amylase and glucosidase inhibitors

Assessment of estrogenic, mutagenic and antimutagenic activity of nemorosone

Currently, a wide range of research involving natural products is focused on the discovery of new drugs in many different therapeutic areas. A great number of the synthetic compounds on the market were derived from natural products, especially plants. Nemorosone is the major constituent of the floral resin of Clusia rosea Jacq., Clusiaceae, and in Cuban propolis. In vitro studies have shown cytotoxic activity in this substance against various tumor cell lines, including those resistant to various cytotoxic drugs, whereas it has low cytotoxicity to non-tumoral cells. Therefore, in order to characterize the biological activity of nemorosone, a substance with potential antitumor activity, and in view of preclinical testing of the toxicity of drug candidate compounds, the main aim of this study was to determine the mutagenic and antimutagenic activity of nemorosone by the Ames test, using the strains TA97a, TA98, TA100 and TA102 of Salmonella typhimurium. Secondly, to characterize the estrogenic activity in an experimental recombinant yeast model (Recombinant Yeast Assay) mutagenic activity was observed at in any of the concentrations in any of the test strains. To evaluate the antimutagenic potential, direct and indirect mutagenic agents were used: 4 nitro-o-phenylenediamine (NPD), mitomycin C (MMC) and aflatoxin B1 (AFL). Nemorosone showed moderate antimutagenic activity (inhibition level 31%), in strain TA100 in the presence of AFL, and strong antimutagenic activity in TA102 against MMC (inhibition level 53%). Estrogenic activity was observed, with an EEq of 0.41±0.16 nM at various tested concentrations.

Mutagenicity and antimutagenicity of (-)-hinokinin a trypanosomicidal compound measured by Salmonella microsome and comet assays

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

Determination of amfepramone hydrochloride, fenproporex, and diazepam in so-called natural capsules used in the treatment of obesity

A simple and rapid method was developed for the determination of amfepramone hydrochloride, fenprorex, and diazepam in capsules using high performance liquid chromatography (HPLC) with UV detection. This procedure provided conditions for the separation of the active ingredient from the complex matrices of the dosage forms by extraction in methanol. Isocratic reversed phase chromatography was performed using acetonitrile, methanol, and aqueous 0,1% ammonium carbonate (50:10:40) as a mobile phase, LiChrospher 100 RP 18 column (125 x 5 mm id, 5 mu m), a column temperature of 25 +/- 1 degrees C and detection at 230 nm.The calibration curves were linear over a wide concentration range (20-2000 mu g.mL(-1) to amfepramone hydrochloride, 8-800 mu g.mL(-1) to fenproporex, and 4-200 mu g.mL(-1) to diazepam) and good analytical recovery (87.1 to 107.8%) was obtained. The method is accurate and precise, as well as having advantages such as simplicity and short duration of analysis. Twenty samples of pharmaceutical preparations labelled as natural products were analysed. Anorectics and diazepam, were detected in 40% of the samples.

In vitro effects of propolis on Giardia duodenalis trophozoites

In order to improve the current chemotherapy of Giardia infection, potential antigiardial agents have been screened, including natural products. Propolis, a resinous hive product collected by bees, has attracted attention as a useful and popular substance with several therapeutic activities. The present study was carried out aiming to evaluate the in vitro effects of an ethanolic extract of propolis on the growth and adherence of Giardia duodenalis trophozoites. Propolis inhibited the growth of trophozoites and the level of inhibition varied according to the extract concentration and incubation times. The highest reduction of parasite growth was observed in cultures exposed to 125, 250 and 500 mu g/ml of propolis, in all incubation periods (24, 48, 72 and 96 h). Growth reduction by 50% was observed in 125 mu g/ml propolis-treated cultures, while the concentrations of 250 and 500 mu g/ml were able to inhibit growth by more than 60%. Propolis also inhibited parasite adherence and all assayed propolis concentrations promoted the detachment of trophozoites. Light microscope observations revealed changes of the pear-shaped aspect of the cell and reduction of flagellar beating frequency in the great part of the trophozoites. Our results hold the perspective for the utilization of propolis as an antigiardial agent. (c) 2005 Elsevier GmbH. All rights reserved.

New sources of oilseeds from Latin American native fruits

Three Latin American oilseeds obtained from native fruits: nopal (tuna) (Opuntia ficus-indica), cherimoya (chirimoya) (Annona cherimola), and papaya, Chilean variety (Carica pubescens or C. candamarcensis) were studied for their fatty acid composition and bioactive compounds, such as tocols and phytosterols, looking for new sources of special oilseeds for this region. The results indicated that each species represents an interesting possibility. Nopal oilseed is a good source of linoleic acid (62%), with a good balance between SFA and MUFA (1: 1.3). Cherimoya oilseed presents quite a different composition, with 24% SFA, 43% MUFA and 33% PUFA. Palmitic and stearic acids (15% and 7.6%, respectively) are the main SFA. A good balance between oleic acid (42.7%) and linoleic acid (31%) was observed. Papaya oilseed is a highly MUFA oil (72% with 71% oleic acid), with a very interesting composition, according to the new nutritional and technological recommendations.With respect to bioactive compounds, the main tocol in these three oilseeds was gamma-tocopherol, with 136, 300 and 317 mg/kg for cherimoya, papaya and nopal oilseeds, respectively. According to the total tocol content, papaya oilseed presented the highest value with 384 mg/kg. The total amount and distribution of phytosterols was different, with values of 3092, 3554 and 5474 mg/kg for nopal, cherimoya and papaya oilseeds, respectively, with beta-sitosterol forming 47.6%, 65.0 % and 78.7% of the total phytosterol fractions, respectively. From the results obtained, Chilean papaya oilseed can be considered as a very promising new source of special plant oil for different applications, followed by cherimoya and nopal oilseeds.

Resolution and Absolute Configuration Assignment of a Natural Racemic Chromane from Peperomia obtusifolia (Piperaceae)

The resolution of the natural racemic chromane 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3 ''-methyl-2 ''-butenyl)-2-(4'-methyl-1',3'-pentadienyl)-2H-1-benzopyran-6-carboxylic acid (1) isolated from the leaves of Peperomia obtusifolia has been accomplished using stereoselective HPLC. The absolute coil figuration of the resolved enantiomers was determined by the analysis of optical rotations and CD spectra. The finding of a racemic mixture instead of an enantiomerically pure metabolite raises questions about the final steps in the biosynthesis of this class of natural products, suggesting that the intramolecular chromane ring formation step may not be enzymatically controlled at all in P. obtusifolia. Chirality 21:799-801, 2009. (C) 2008 Wiley-Liss, Inc.

Immunological and microbiological activity of Davilla elliptica St. Hill. (Dilleniaceae) against Mycobacterium tuberculosis

Mycobacterium tuberculosis is responsible for over 8 million cases of tuberculosis (TB) annually. Natural products may play important roles in the chemotherapy of TB. The immunological activity of Davilla elliptica chloroform extract (DECE) was evaluated in vitro by the determination of hydrogen peroxide (H2O2), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-alpha) release in peritoneal macrophages cultures. DECE was also tested for its antimycobacterial activity against M. tuberculosis using the microplate alamar blue assay. DECE (50, 150, 250 µg/ml) stimulated the production of H2O2 (from 1,79 ± 0,23 to 7,27 ± 2,54; 15,02 ± 2,86; 20,5 ± 2,1 nmols) (means ± SD), NO (from 2,64 ± 1,02 to 25,59 ± 2,29; 26,68 ± 2,41; 29,45 ± 5,87 µmols) (means ± SD) and TNF-alpha (from 2,44 ± 1,46 to 30,37 ± 8,13; 38,68 ± 1,59; 41,6 ± 0,90 units/ml) (means ± SD) in a dose-dependent manner and also showed a promising antimycobacterial activity with a minimum inhibitory concentration of 62,5 µg/ml. This plant may have therapeutic potential in the immunological and microbiological control of TB.

Automatic identification by C-13 NMR of substituent groups bonded in natural product skeletons

The aim of this paper is to present a procedure that utilizes C-13 NMR for identification of substituent groups which are bonded to carbon skeletons of natural products. For so much was developed a new version of the program (MACRONO), that presents a database with 161 substituent types found in the most varied terpenoids. This new version was widely tested in the identification of the substituents of 60 compounds that, after removal of the signals that did not belong to the carbon skeleton, served to test the prediction of skeletons by using other programs of the expert system (SISTEMAT). (C) 2002 Elsevier B.V. Ltd. All rights reserved.

New anti-Alzheimer drugs from biodiversity: the role of the natural acetylcholinesterase inhibitors

Alzheimer's disease (AD) is a progressive neurodegenerative pathology with severe economic and social impact. There is currently no cure, although cholinesterase inhibitors provide effective temporary relief of symptoms in some patients. Nowadays, drug research and development are based on the cholinergic hypothesis that supports the cognition improvement by regulation of the synthesis and release of acetylcholine in the brain. There are only four commercial medicines approved for treatment of AD, and natural products have played an important alternative role in the research for new acetylcholinesterase inhibitors, as exemplified through the discovery of galantamine. This profile conducts us to give in this paper an overview relating the several classes of natural products with anti-cholinesterasic activity as potential templates to the design of new selective and powerful anti-Alzheimer drugs.