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The spread of multidrug-resistant Staphylococcu s aureus strains, including methicillin-resistant S . aureus (MRSA), has shortened the useful life of anti-staphylococcal drugs enormously. Two approaches can be followed to address this problem: screening various sources for new leads for antibiotics or finding ways to disable the resistance mechanisms to existing antibiotics. Plants are resistant to most microorganisms, but despite extensive efforts to identify metabolites that are responsible for this resistance, no substantial progress has been made. Plants possibly use multiple strategies to deal with microorganisms that evolved over time. For this reason, we searched for plants that could potentiate the effects of known antibiotics. From 29 plant species tested, Cytisus striatus clearly showed such an activity and an NMR-based metabolomics study allowed the identification of compounds from the plant extracts that could act as antibiotic adjuvants. Isoflavonoids were found to potentiate the effect of ciprofloxacin and erythromycin against MRSA strains. For the structure-activity relationship (SAR), 22 isoflavonoids were assessed as antibiotic adjuvants. This study reveals a clear synergy between isoflavonoids and the tested antibiotics, showing their great potential for applications in the clinical therapy of infections with antibiotic-resistant microorganisms such as MRSA.

As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL−1 for DPPH· and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL−1 for ABTS·+, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O-b-glucoside (3), and quercetin-3-O-b-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported.

IntroductionLantana trifolia L. (Verbenaceae) is a shrubby plant. In folk medicine, its leaves are used in the form of infusions and syrups to treat angina, coughs, and colds; they are also applied as tranquilizer. Previous studies have reported the antimicrobial potential of the compounds present in L. trifolia leaves.ObjectivesTo report the anti-Candida activities of the fractions obtained from the fruits and leaves of two L. trifolia specimens.MethodsThe L. trifolia fractions were submitted to UFLC-DAD-(+)-ESI-MS/MS, and the data were analyzed by using multivariate statistical tools (PCA, PLS-DA) and spectral similarity analyses based on molecular networking, which aided dereplication of the bioactive compounds. Additionally, NMR analyses were performed to confirm the chemical structure of some of the major compounds in the fractions.ResultsThe ethyl acetate fractions presented MIC values lower than 100 µg mL–1 against the three Candida strains evaluated herein (C. albicans, C. tropicalis, and C. glabrata). Fractions FrPo AcOEt, FrPe AcOEt, and FrPe nBut had MIC values of 1.46, 2.93, and 2.93 µg mL–1 against C. glabrata, respectively. These values resembled the MIC value of amphotericin B, the positive control (0.5–1.0 µg mL–1), against this same strain. Cytotoxicity was measured and used to calculate the selectivity index.ConclusionOn the basis of our data, the most active fractions in the antifungal assay were more selective against C. glabrata than against non-infected cells. The analytical approach adopted here allowed us to annotate 29 compounds, nine of which were bioactive (PLS-DA results) and belong to the class of phenolic compounds.

Pinhão residues have a wide range of bioactive compounds and encapsulation can be one of the alternatives to increase their bioavailability. Thus, this work aimed to apply pinhão extract, pure and encapsulated by solid dispersion, in the formulation of cookies as a bioactive ingredient. For that, pinhão extract was encapsulated in different biopolymers (sodium caseinate, gelatin, and gum arabic) and with different shear mechanisms (sonication, Ultra-Turrax, and magnetic stirring). The best encapsulation procedure has been defined by a chemometric analysis (hierarchical cluster analysis), considering thermal properties (DSC) of particles and ( +)-catechin encapsulation efficiency (HPLC). The optimized conditions were gelatin as encapsulation agent and Ultra-Turrax as shear mechanism (70.1 ± 2.8 °C maximum endothermic peak temperature and 96.0 ± 2.3% ( +)-catechin encapsulation efficiency). The phenolic profile of the encapsulated extract showed the presence of ( +)-catechin (0.31 ± 0.01 (mg/g particle ), protocatechuic acid (0.29 ± 0.00 mg/g particle ), and ( −)-epicatechin (0.11 ± 0.00 mg/g particle ). Both the pure and encapsulated extracts were incorporated into the cookie formulation, which was characterized in terms of centesimal composition, color parameters, texture, and sensory aspects. It was found that cookies with the pure and the encapsulated extract showed significant differences concerning the centesimal composition, products added with pinhão extract and encapsulated extract presented higher values when compared to the control, probably influenced by the mineral content of the pinhão.  In addition, higher hardness values were detected for cookies formulated with the encapsulated extract, which possibly negatively affected the consumer’s sensory perception.

IntroductionThe increase in multidrug resistance and lack of efficacy in malaria therapy has propelled the urgent discovery of new antiplasmodial drugs, reviving the screening of secondary metabolites from traditional medicine. In plant metabolomics, NMR-based strategies are considered a golden method providing both a holistic view of the chemical profiles and a correlation between the metabolome and bioactivity, becoming a corner stone of drug development from natural products.ObjectiveCreate a multivariate model to identify antiplasmodial metabolites from 1H NMR data of two African medicinal plants, Keetia leucantha and K. venosa.MethodsThe extracts of twigs and leaves of Keetia species were measured by 1H NMR and the spectra were submitted to orthogonal partial least squares (OPLS) for antiplasmodial correlation.ResultsUnsupervised 1H NMR analysis showed that the effect of tissues was higher than species and that triterpenoids signals were more associated to Keetia twigs than leaves. OPLS–DA based on Keetia species correlated triterpene signals to K. leucantha, exhibiting a higher concentration of triterpenoids and phenylpropanoid-conjugated triterpenes than K. venosa. In vitro antiplasmodial correlation by OPLS, validated for all Keetia samples, revealed that phenylpropanoid-conjugated triterpenes were highly correlated to the bioactivity, while the acyclic squalene was found as the major metabolite in low bioactivity samples.ConclusionNMR-based metabolomics combined with supervised multivariate data analysis is a powerful strategy for the identification of bioactive metabolites in plant extracts. Moreover, combination of statistical total correlation spectroscopy with 2D NMR allowed a detailed analysis of different triterpenes, overcoming the challenge posed by their structure similarity and coalescence in the aliphatic region.

This work aims to investigate the effect of process temperature and catalyst content by pyrolysis and thermal catalytic cracking of (organic matter + paper) fraction from municipal household solid waste (MHSW) on the yields of reaction products (bio-oil, bio-char, H2O, and gas), acid value, chemical composition of bio-oils, and characterization of bio-chars in laboratory scale. The collecting sectors of MHSW in the municipality of Belém-Pará-Brazil were chosen based on geographic and socio-economic database. The MHSW collected and transported to the segregation area. The gravimetric analysis of MHSW was carried out and the fractions (Paper, Cardboard, Tetra Pack, Hard Plastic, Soft Plastic, Metal, Glass, Organic Matter, and Inert) were separated. The selected organic matter and paper were submitted to pre-treatment of crushing, drying, and sieving. The experiments carried out at 400, 450, and 475 °C and 1.0 atmosphere, and at 475 °C and 1.0 atmosphere, using 5.0, 10.0, and 15.0% (wt.) Ca(OH)2, in batch mode. The bio-oil was characterized for acid value. The chemical functions present in bio-oil were identified by FT-IR and the composition was identified by GC-MS. The bio-char was characterized by SEM, FT-IR, and XRD. The variance in mass (wt.%) for organic fractions of municipal household solid waste (OFMHSW), between 56.21 and 67.45% (wt.), lies with the interval of 56% (wt.) and 64% (wt.) of OFMHSW for middle- and low-income countries. The pyrolysis of MHSW fraction (organic matter + paper) shows bio-oil yields between 2.63 and 9.41% (wt.), aqueous phase yields between 28.58 and 35.08% (wt.), solid phase yields between 35.29 and 45.75% (wt.), and gas yields between 16.54 and 26.72% (wt.). The bio-oil yield increases with pyrolysis temperature. For the catalytic cracking, the bio-oil and gas yields increase slightly with CaO content, while that of bio-char decreases, and the H2O phase remains constant. The GC-MS of liquid reaction products identified the presence of hydrocarbons (alkanes, alkenes, alkynes, cycloalkanes, and aromatics) and oxygenates (carboxylic acids, ketones, esters, alcohols, phenols, and aldehydes), as well as compounds containing nitrogen, including amides and amines. The acidity of bio-oil decreases with increasing process temperature and with aid Ca(OH)2 as a catalyst. The concentration of hydrocarbons in bio-oil increases with increasing Ca(OH)2-to-OFMHSW fraction ratio due to the catalytic deoxygenation of fatty acid molecules, by means of decarboxylation/decarbonylation, producing aliphatic and aromatic hydrocarbons.

We present selected anthropometric data, specific for sex and age group, from a representative sample of elderly subjects living in Havana, Cuba. This was a cross-sectional, population-based household survey. A total of 1905 subjects (1197 women and 708 men, ≥60 y of age) were examined between 1999 and 2000 as selected by probabilistic sampling. Data were presented as means and percentiles for body mass; height or stature; body mass index; waist, arm, and calf circumferences; triceps skinfold thickness; and arm muscle circumference; and differences were described according to age (all variables) and sex (body mass index). All anthropometric variables showed a decrease in average values with aging in men and women. The age of 70 y appeared to be the decisive moment for the main anthropometric differences observed. The values in the female group were higher than those in the male group for body mass index and triceps skinfold thickness. An important segment of the population studied had a body mass index lower than normal values. Reductions in subcutaneous fat (indicated by triceps skinfold thickness) and muscle mass (verified by arm, arm muscle, and calf circumferences) with advancing age appeared to be greater among women than among men. The present study provides information that can be used for anthropometric evaluation of elderly people in Havana and other urban areas in Cuba. The observations suggest that there is loss of muscle mass and redistribution and reduction of fat mass with age (that is more severe in women).

To assess the association of nutritional status with sex, age, race/color, education, smoking, physical activity, hypertension, diabetes, and hospitalization in older adults residing in the city of Havana, Cuba. This was a cross-sectional, population-based household survey. A total of 1,905 persons (1,197 women and 708 men; ≥ 60 years) were examined between 1999 and 2000, selected by probabilistic sampling. Nutritional status was assessed by body mass index (BMI): BMI < 22.0 kg/m2 = underweight; BMI > 27.0 kg/m2 = overweight. Multinomial logistic regression analysis (crude and adjusted) was used. The estimation of the prevalence of underweight was 33.0% and that of overweight was 29.6%. The adjusted regression model showed that the probability of underweight was higher in older age groups (OR = 1.63, 70-79 years; OR = 2.05, ≥ 80 years) and among smokers (OR = 1.83). There was negative association between underweight, and hypertension and diabetes. Hypertension (OR = 1.99) was positively associated with overweight. The lower likelihood of overweight was observed among men, smokers, and those aged 80 years and more. The elderly population of Havana presents a vulnerable nutritional status in view of the prevalence of underweight and overweight. Increasing age, smoking, gender, and hypertension are the factors positively associated with vulnerable nutritional status.

Background and Purpose: The use of anthropometric indicators as discriminators of hypertriglyceridemia has not been thoroughly investigated. The purpose of this article is to comparatively evaluate anthropometric indicators as discriminators of hypertriglyceridemia in older Brazilian adults. Methods: This cross-sectional study derived from population-based epidemiological research involving 316 community-dwelling older adults (60-105 years old). Results: Except for the conicity index and the body adiposity index in the group of women, all other anthropometric indicators (i.e., body mass index, waist and calf circumferences, triceps skinfold thickness, and waist-stature and waist-hip ratios) were sufficient to identify hypertriglyceridemia in the population. Conclusions: We endorse anthropometric indicators for use in screening for hypertriglyceridemia in older Brazilian adults.