2,2′-Dimethoxy-4,4′-[rel-(2R,3S)-2,3-di­methylbutane-1,4-diyl]diphenol

The title mol­ecule, C20H26O4, commonly known as meso-dihydro­guaiaretic acid, is a naturally occurring lignan extracted from Larrea tridentata and other plants. The mol­ecule has a noncrystallographic inversion center situated at the midpoint of the central C—C bond, generating the meso stereoisomer. The central C—C—C—C alkyl chain displays an all-trans conformation, allowing an almost parallel arrangement of the benzene rings, which make a dihedral angle of 5.0 (3)°. Both hydr­oxy groups form weak O—H⋯O—H chains of hydrogen bonds along [100]. The resulting supra­molecular structure is an undulating plane parallel to (010)

The bioactivity of plant extracts against representative bacterial pathogens of the lower respiratory tract

<p>Abstract</p> <p>Background</p> <p>Lower respiratory tract infections are a major cause of illness and death. Such infections are common in intensive care units (ICU) and their lethality persists despite advances in diagnosis, treatment and prevention. In Mexico, some plants are used in traditional medicine to treat respiratory diseases or ailments such as cough, bronchitis, tuberculosis and other infections. Medical knowledge derived from traditional societies has motivated searches for new bioactive molecules derived from plants that show potent activity against bacterial pathogens. Therefore, the aim of this study was to evaluate the effect of hexanic, chloroformic (CLO), methanolic (MET) and aqueous extracts from various plants used in Mexican traditional medicine on various microorganisms associated with respiratory disease.</p> <p>Methods</p> <p>thirty-five extracts prepared from nine plants used in Mexican traditional medicine for the treatment of respiratory infections were evaluated against 15 control bacterial species and clinical isolates.</p> <p>Results</p> <p>Both chloroformic (CLO) and methanolic (MET) extracts of <it>Larrea tridentata </it>were active against Methicillin-resistant <it>S. aureus</it>, <it>B. subtilis </it>and <it>L. monocytogenes</it>. A MET extract of <it>L. tridentata </it>was also active against <it>S. aureus</it>, <it>S. pneumoniae</it>, <it>S. maltophilia</it>, <it>E. faecalis </it>and <it>H. influenzae </it>and the CLO extract was active against <it>A. baumannii</it>. An Aqueous extract of <it>M. acumitata </it>and a MET extract of <it>N. officinale </it>were active against <it>S. pneumoniae</it>. CLO and MET extracts of <it>L. tridentata </it>were active against clinical isolates of <it>S. aureus</it>, <it>S. pneumoniae </it>and <it>E. faecalis</it>.</p> <p>Conclusion</p> <p>Overall, our results support the potential use of <it>L. tridentata </it>as a source of antibacterial compounds.</p

Vasodilator Activity of Compounds Isolated from Plants Used in Mexican Traditional Medicine

Abstract: Arterial hypertension is one of the main risk factors in the development of cardiovascular diseases. Therefore, it is important to look for new drugs to treat hypertension. In this study, we carried out the screening of 19 compounds (triterpenes, diterpenes, sesquiterpenes, lignans, and flavonoids) isolated from 10 plants used in Mexican traditional medicine to determine whether they elicited vascular smooth muscle relaxation and, therefore, could represent novel anti-hypertension drug candidates. The vasorelaxant activity of these compounds was evaluated on the isolated rat aorta assay and the results obtained from this evaluation showed that three compounds induced a significant vasodilatory effect: meso-dihydroguaiaretic acid [half maximal effective concentration (EC50), 49.9 ± 11.2 µM; maximum effect (Emax), 99.8 ± 2.7%]; corosolic acid (EC50, 108.9 ± 6.7 µM; Emax, 96.4 ± 4.2%); and 5,8,40-trihydroxy-3,7-dimethoxyflavone (EC50, 122.3 ± 7.6 µM; Emax, 99.5 ± 5.4%). Subsequently, involvement of the NO/cyclic guanosine monophosphate (cGMP) and H2S/ATP-sensitive potassium channel (KATP) pathways on the vasodilator activity of these compounds was assessed. The results derived from this analysis showed that the activation of both pathways contributes to the vasorelaxant effect of corosolic acid. On the other hand, the vasodilator effect of meso-dihydroguaiaretic acid and 5,8,40-trihydroxy-3,7-dimethoxyflavone, partly involves stimulation of the NO/cGMP pathway. However, these compounds also showed an important endothelium-independent vasorelaxant effect, whose mechanism of action remains to be clarified. This study indicates that meso-dihydroguaiaretic acid,corosolicacid,and5,8,40-trihydroxy-3,7-dimethoxyflavonecouldbeusedasleadcompoundsfor the synthesis of new derivatives with a higher potency to be developed as drugs for the prevention and treatment of cardiovascular diseases. Keywords: corosolic acid; 5,8,40-trihydroxy-3,7-dimethoxyflavone; meso-dihydroguaiaretic acid hydrogen sulfide; nitric oxide; vasorelaxatio

Bioassay-guided identification of the antiproliferative compounds of cissus trifoliata and the transcriptomic effect of resveratrol in prostate cancer pc3 cells

The bioassay-guided fractionation of a CHCl3-MeOH extract from the stems of Cissus trifo-liata identified an active fraction against PC3 prostate cancer cells. The treatment for 24 h showed an 80% reduction in cell viability (p ≤ 0.05) by a WST-1 assay at a concentration of 100 µg/mL. The HPLC-QTOF-MS analysis of the fraction showed the presence of coumaric and isoferulic acids, apigenin, kaempferol, chrysoeriol, naringenin, ursolic and betulinic acids, hexadecadienoic and octadecadienoic fatty acids, and the stilbene resveratrol. The exposure of PC3 cells to resveratrol (IC25 = 23 µg/mL) for 24 h induced significant changes in 847 genes (Z-score ≥ ±2). The functional classification tool of the DAVID v6.8 platform indicates that the underlying molecular mechanisms against the proliferation of PC3 cells were associated (p ≤ 0.05) with the process of differentiation and metabolism. These findings provide experimental evidence suggesting the potential of C. trifoliata as a promising natural source of anticancer compounds

Anti-giardia activity of hexane extract of Citrus aurantifolia (Christim) swingle and some of its constituents

Background: Giardia lamblia is a parasite that causes giardiasis in humans and other mammals. The common treatment includes different drugs, which were described to produce unpleasant side effects. Citrus aurantifolia, popularly known as “lima”, is a plant used in traditional medicine to treat gastrointestinal symptoms. The aim of the present study was to evaluate the anti-Giardia activity of 10 pure compounds obtained from a hexanic extract of Mexican lime on the basis of trophozoite growth inhibition.Materials and Methods: A hexanic extract obtained from fresh fruit peels of Citrus aurantifolia was tested on G. lamblia strain 0989:IMSS trophozoites cultured in TYI-S-33 medium. The concentration of all standard drugs, analyzed by gas chromatography, was adjusted at 10 mg/mL. Metronidazole was used as a positive control. Growth inhibition was determined by counting the number of trophozoites using a Neubauer chamber. The 50% inhibitory concentration (IC50) of each drug was calculated by probit analysis and 95% confidence limits were calculated.Results: 4-hexen-3-one, citral and geraniol showed IC50 values of 34.2, 64.5 and 229.49 μg/ml in axenic cultures after 24 hr of incubation, respectively. When these results were compared with a positive control of metronidazole; 4-hexen-3-one was 66 times; citral was 112 and geraniol was 441 times less active respectively. The other tested compounds did not inhibit the growth of cultured G. lamblia trophozoites.Conclusion: The obtained results lead us to propose that these tested compounds from C. aurantifolia have potential for use as therapeutic agents against giardiasis.Keywords: antigiardial ; Citrus aurantifolia; antiprotozoal activity; Giardia lambli

Identification and distribution of Brachyspira species in feces from finishing pigs in Argentina

Brachyspira are Gram-negative, aerotolerant spirochetes that colonize the large intestine of various species of domestic animals and humans. The aim of this study was to determine the presence and distribution of different species of Brachyspira presents in feces from finishing pigs in Argentina.Materials and Methods: Fecal samples (n=1550) were collected from finishing pigs in 53 farms of the most important swine production areas of Argentina, and Brachyspiras species were identified by bacteriological and molecular methods.Results: The regional prevalence of Brachyspira spp. was at the level of 75.5% (confidence interval 95%, 62.9-87.9), and it was lower among those farms with >1001 sows. One hundred and twenty-eight isolates of Brachyspira were properly identified and the species found were: Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira innocens, and Brachyspira murdochii. B. hyodysenteriae and B. pilosicoli had low prevalence (1.9% and 7.5%, respectively), B. innocens was isolated from 34% of the farms and B. murdochii was found in 39.6%.Conclusion: The present study provides epidemiological data about herd prevalence of the different Brachyspira species in Argentina, showing that the prevalence figure seems to be higher than that reported in other countries.Fil: Carranza, Alicia Estela. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Parada, Julian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Tamiozzo, Pablo Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Flores León, Malena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Camacho Ortega, Pablo Alfredo. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Di Cola, Gabriel. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Corona-Barrera, Enrique. Autonomous University Of Tamaulipas; MéxicoFil: Ambrogi, Arnaldo. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; ArgentinaFil: Zielinski, Gustavo Carlos. Instituto Nacional de Tecnología Agropecuaria; Argentin