ABSTRACT Spathulenol was isolated from an extract of Azorella compacta Phil., Apiaceae, by various chromatographic method; identification of the chemical structure was confirmed by comparing its spectroscopic data with those reported in the literature. The anti-Mycobacterium tuberculosis activity of spathulenol was evaluated on MDR, pre-XDR, and XDR clinical isolates of M. tuberculosis, as well as on the reference susceptible strain H37Rv and its cytotoxic activity was evaluated on the Vero Cell Line. The anti-M. tuberculosis activity of spathulenol was twice as potent against the MDR, pre-XDR, and XDR clinical isolates (6.25 µg/ml) than on the susceptible H37Rv strain (12.5 µg/ml). Additionally, the anti-M. tuberculosis activity shown by spathulenol was established as bactericidal on drug-resistant and susceptible strains of M. tuberculosis. Finally, cytotoxic activity on the Vero cell line (CC50 = 95.7 µg/ml) indicated that spathulenol is a selective anti-M. tuberculosis compound, with a selective index of 15.31 against drug-resistant clinical isolates of M. tuberculosis.

Abstract: Infectious diseases remain a public health problem that is exacerbated by the presence of resistant organisms leading to development of novel drugs. Study of pharmacological proteins from natural sources recently emerged. In this research extraction of proteins from gel of Aloe vera and antimicrobial evaluation were done. Protein extracts from Aloe vera were obtained by two methods: extract 1(EP1) by precipitation with (NH4)2SO4 and (EP2) by phenol extraction. The yield for method 2 (0.33 % recovery). Analysis by mass spectrometry of EP1 identified with a high degree of confidence, peptide 5 and 31-kDa protein, whose identity has been associated with the glycoproteins of Arabidopsis thaliana. EP2 exhibited inhibitory activity against Staphylococcus aureus and Candida albicans. A. vera extract comprises a promising source of protein with anti-S. aureus and anti-C. albicans activity.

Resumen: Las enfermedades infecciosas son un problema de Salud Pública que se agrava con microorganismos resistentes. Esto conduce al desarrollo de nuevos fármacos. Recientemente surgió el estudio de actividades farmacológicas de proteínas de fuentes naturales. En esta investigación se realizó la extracción de proteínas del gel de Aloe vera y su evaluación antimicrobiana. Se obtuvieron extractos proteicos de A. vera por dos métodos: Extracto 1 (EP1) precipitación con (NH4)2SO4 y extracto 2 (EP2) extracción con fenol. El rendimiento para el método 2 (0.33 % recuperación). Análisis por espectrometría de masas EP1 permitió identificar un péptido y una proteína de 5 y 31 kDa, relacionada con glicoproteínas de Arabidopsis thaliana. EP2 mostró actividad contra Staphyllococcus aureus y Candida albicans. A. vera es una fuente prometedora de proteínas con actividad anti-S. aureus y -C. albicans.

The characteristics of tuberculosis (TB) patients related to a chain of recent TB transmissions were investigated. Mycobacterium tuberculosis (MTB) isolates (120) were genotyped using the restriction fragment length polymorphism-IS6110 (R), spacer oligotyping (S) and mycobacterial interspersed repetitive units-variable number of tandem repeats (M) methods. The MTB isolates were clustered and the clusters were grouped according to the similarities of their genotypes. Spearman’s rank correlation coefficients between the groups of MTB isolates with similar genotypes and those patient characteristics indicating a risk for a pulmonary TB (PTB) chain transmission were ana- lysed. The isolates showing similar genotypes were distributed as follows: SMR (5%), SM (12.5%), SR (1.67%), MR (0%), S (46.67%), M (5%) and R (0%). The remaining 35 cases were orphans. SMR exhibited a significant correlation (p < 0.05) with visits to clinics, municipalities and comorbidities (primarily diabetes mellitus). S correlated with drug consumption and M with comorbidities. SMR is needed to identify a social network in metropolitan areas for PTB transmission and S and M are able to detect risk factors as secondary components of a transmission chain of TB.

The resistance of 139 Mycobacterium tuberculosis (MTB) isolates from the city of Monterrey, Northeast Mexico, to first and second-line anti-TB drugs was analysed. A total of 73 isolates were susceptible and 66 were resistant to anti-TB drugs. Monoresistance to streptomycin, isoniazid (INH) and ethambutol was observed in 29 cases. Resistance to INH was found in 52 cases and in 29 cases INH resistance was combined with resistance to two or three drugs. A total of 24 isolates were multidrug-resistant (MDR) resistant to at least INH and rifampicin and 11 MDR cases were resistant to five drugs. The proportion of MDR-TB among new TB cases in our target population was 0.72% (1/139 cases). The proportion of MDR-TB among previously treated cases was 25.18% (35/139 cases). The 13 polyresistant and 24 MDR isolates were assayed against the following seven second-line drugs: amikacin (AMK), kanamycin (KAN), capreomycin (CAP), clofazimine (CLF), ethionamide (ETH), ofloxacin (OFL) and cycloserine (CLS). Resistance to CLF, OFL or CLS was not observed. Resistance was detected to ETH (10.80%) and to AMK (2.70%), KAN (2.70%) and CAP (2.70%). One isolate of MDR with primary resistance was also resistant to three second-line drugs. Monterrey has a high prevalence of MDR-TB among previously treated cases and extensively drug-resistant-MTB strains may soon appear.

The results on the bioevaluation of thirty five plant-derived secondary metabolites against one sensitive and three multidrug-resistant clinical isolates of Mycobacterium tuberculosis are reported. Results toward the sensitive strain showed that five products gave MIC values of 12.5 µg/mL: the alkaloids 6-methoxydihydrochelerytrine (2) and 6-methoxy-dihydrochelirubine (6), the flavanone pinostrobin (17), 1-hydroxy-benzoisochromanquinone (23) and 23-hydroxy-5a-lanosta-7,9(11),24-triene-3-one (33). These were followed by the peracetylstrictosidine lactam (12) and the quinone aloe-emodin (24) which displayed MICs of 6.25 µg/mL. Finally, liriodenine (8) was the most active (MIC: 3.125 µg/mL) of all secondary metabolites. Results with the multidrug-resistant clinical isolates showed that 6-methoxy-dihydrochelirubine (6) was the most active (MIC: 12.5 µg/mL).

Se informan los resultados sobre la bioevaluación de treinta y cinco metabolitos secundarios de plantas frente a una cepa sensible y a tres cepas resistentes a múltiples drogas de Mycobacterium tuberculosis. Los resultados frente a la cepa sensible mostraron que cinco metabolitos secundarios poseen valores de CMI de 12.5 µg/mL: los alcaloides 6-metoxidihidroqueleritrina (2) y 6-metoxi-dihidroque-lirubina (6), la flavanona pinostrobina (17), 1-hidroxi-benzoisocromanquinona (23) y el triterpeno 23-hidroxi-5a-lanosta-7,9(11),24-trien-3-ona (33). La lactama de peracetilestrictosidina (12) y la quinona aloe-emodina (24) mostraron CMIs de 6.25 µg/mL. Finalmente, liriodenina (8) fue la substancia mas activa (CMI: 3.125 µg/mL) de todos los metabolitos secundarios. Los resultados con los aislados clínicos resistentes a multidrogas mostraron que 6-metoxi-dihidroquelirubina (6) fue el compuesto mas activo (CMI: 12.5 µg/mL).