Evaluación de la actividad antimicrobiana in vitro de mentha frente a candida albicans / Evaluation of the in vitro antimicrobial activity of mentha against candida albicans

El uso de la medicina natural tradicional es actualmente una parte importante relacionada con la salud, en algunos países de Latinoamérica se la conoce como medicina complementaria, la cual históricamente se ha utilizado para mantener la salud, prevenir y tratar enfermedades crónicas. En el presente proyecto de investigación se propuso determinar si existe algún efecto antimicrobiano significativo contra el microorganismo Cándida albicans en el extracto alcohólico o aceite esencial obtenidos a partir de la planta menta. La investigación comprendió tres etapas: el estudio etnofarmacológico, el análisis fitoquímico y el análisis de actividad antimicrobiana. Al concluir la primera etapa se estableció que las plantas de acuerdo al nivel de uso significativo (UST%), presentan los siguientes valores: menta (29,41%), sábila (23,08%) y manzanilla (21,72%). En el análisis fitoquímico se determinó la presencia de ciertos metabolitos secundarios de la planta medicinal menta como los terpenoides y compuestos fenólicos (cumarinas, flavonoides, lignina y taninos). Dentro del análisis microbiológico, se presentó mayor efectividad a una concentración de 100%, obteniéndose halos promedio de 17,67mm y 16,67mm para aceite esencial y extracto etanólico respectivamente. La prueba de varianzas realizada como análisis estadístico determinó que alguna de las medias de las distribuciones de la variable cuantitativa (halos de inhibición) en los extractos y aceites de menta es diferente (15,907 con un valor de p < 0,05), afirmando que existen efecto antimicrobiano de la menta sobre Cándida albicans.

Integracides H-J: New tetracyclic triterpenoids from the endophytic fungus Fusarium sp.

Three new tetracyclic triterpenoids namely, integracides H (1), I (4), and J (5), along with integracides B (3) and F (2) have been isolated from the endophytic fungus Fusarium sp. isolated from the roots of Mentha longifolia L. (Labiatae) growing in Saudi Arabia. The structure elucidation of the isolated compounds was achieved by spectroscopic analysis including UV, IR, 1D ((1)H and (13)C) and 2D ((1)H(1)H COSY, TOCSY, HSQC, HMBC, and NOESY) NMR as well as HRESIMS and comparison with literature data. Integracides H (1) and J (5) showed significant anti-leishmanial activity towards Leishmania donovani with IC50 values of 4.75 and 3.29µM, respectively compared to pentamidine (IC50 6.35µM). Moreover, they displayed potent cytotoxic activity towards BT-549, SKOV-3, and KB cell lines with IC50 values of 1.82, 1.32, and 0.18µM and 2.46, 3.01, and 2.54µM, respectively.

Verticillium dahliae populations from mint and potato are genetically divergent with predominant haplotypes.

In total, 286 Verticillium dahliae isolates from mint, potato, and other hosts and substrates were characterized for mating type, vegetative compatibility group (VCG), and multilocus microsatellite haplotype to determine population genetic structure among populations infecting mint and potato. Populations from mint and potato fit a clonal reproductive model, with all isolates a single mating type (MAT1-2) and multiple occurrences of the same haplotypes. Haplotype H02 represented 88% of mint isolates and was primarily VCG2B, while haplotype H04 represented 70% of potato isolates and was primarily VCG4A. Haplotypes H02 and H04 typically caused severe disease on mint and potato, respectively, in greenhouse assays regardless of host origin. Principal coordinate analysis and analysis of molecular variance indicated that mint and potato populations were significantly genetically diverged (P = 0.02), and identification of private alleles and estimation of migration rates suggested restricted gene flow. Migration was detected between infected potato plants and seed tubers, infested tare soil, and field soils. Genetic differentiation of V. dahliae from mint and potato may be due to the occurrence of a single mating type and differences in VCG. Populations of V. dahliae in potato and mint were characterized by the presence of aggressive, clonally reproducing haplotypes which are widely distributed in commercial mint and potato production.

A natural plant growth promoter calliterpenone from a plant Callicarpa macrophylla Vahl improves the plant growth promoting effects of plant growth promoting rhizobacteria (PGPRs).

Experiments were conducted to evaluate the efficacy of calliterpenone, a natural plant growth promoter from a shrub Callicarpa macrophylla Vahl., in enhancing the growth and yield promoting effects of plant growth promoting rhizobacteria (PGPRs), in menthol mint (Mentha arvensis L).This study is based on our previous results indicating the microbial growth promotion by calliterpenone and assumption that application of calliterpenone along with PGPRs will improve the population of PGPRs resulting in higher impacts on plant growth and yield. Of the 15 PGPRs (identified as potent ones in our laboratory), 25 µl of 0.01 mM calliterpenone (8.0 µg/100 ml) was found to be useful in improving the population of nine PGPRs in culture media. The five selected strains of PGPRs exhibiting synergy with calliterpenone in enhancing growth of maize compared to PGPR or calliterpenone alone were selected and tested on two cultivars (cvs. Kosi and Kushal) of M. arvensis. Of the five strains, Bacillus subtilis P-20 (16S rDNA sequence homologous to Accession No NR027552) and B. subtilis Daz-26 (16SrDNA sequence homologuos to Accession No GU998816) were found to be highly effective in improving the herb and essential oil yield in the cultivars Kushal and Kosi respectively when co-treated with calliterpenone. The results open up the possibilities of using a natural growth promoter along with PGPRs as a bio-agri input for sustainable and organic agriculture.

Hairy root cultures for secondary metabolites production.

Hairy roots (HRs) are differentiated cultures of transformed roots generated by the infection of wounded higher plants with Agrobacterium rhizogenes. This pathogen causes the HR disease leading to the neoplastic growth of roots that are characterized by high growth rate in hormone free media and genetic stability. HRs produce the same phytochemicals pattern of the corresponding wild type organ. High stability and productivity features allow the exploitation of HRs as valuable biotechnological tool for the production of plant secondary metabolites. In addition, several elicitation methods can be used to further enhance their accumulation in both small and large scale production. However, in the latter case, cultivation in bioreactors should be still optimized. HRs can be also utilised as biological farm for the production of recombinant proteins, hence holding additional potential for industrial use. HR technology has been strongly improved by increased knowledge of molecular mechanisms underlying their development. The present review summarizes updated aspects of the hairy root induction, genetics and metabolite production.