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An overview of the metabolic diversity in ripe fruits of a collection of 32 diverse pepper (Capsicum sp.) accessions was obtained by measuring the composition of both semi-polar and volatile metabolites in fruit pericarp, using untargeted LC-MS and headspace GC-MS platforms, respectively. Accessions represented C. annuum, C. chinense, C. frutescens and C. baccatum species, which were selected based on variation in morphological characters, pungency and geographic origin. Genotypic analysis using AFLP markers confirmed the phylogenetic clustering of accessions according to Capsicum species and separated C. baccatum from the C. annuum-C. chinense-C. frutescens complex. Species-specific clustering was also observed when accessions were grouped based on their semi-polar metabolite profiles. In total 88 semi-polar metabolites could be putatively identified. A large proportion of these metabolites represented conjugates of the main pepper flavonoids (quercetin, apigenin and luteolin) decorated with different sugar groups at different positions along the aglycone. In addition, a large group of acyclic diterpenoid glycosides, called capsianosides, was found to be highly abundant in all C. annuum genotypes. In contrast to the variation in semi-polar metabolites, the variation in volatiles corresponded well to the differences in pungency between the accessions. This was particularly true for branched fatty acid esters present in pungent accessions, which may reflect the activity through the acyl branch of the metabolic pathway leading to capsaicinoids. In addition, large genetic variation was observed for many well-established pepper aroma compounds. These profiling data can be used in breeding programs aimed at improving metabolite-based quality traits such as flavour and health-related metabolites in pepper fruits. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0432-6) contains supplementary material, which is available to authorized users.

The genus Taiwanolepta Kimoto, 1989 (type species Taiwanolepta babai Kimoto, 1989) is proposed as a junior synonym of Sikkimia Duvivier, 1891. Sikkimia species from Taiwan form a group characterized by the reduction of their hind wings. Most of them cannot be distinguished using external morphology, except by the structure of last two antennomeres in males. Diagnoses are made by using distribution, aedeagal, and gonocoxal morphology. The group includes one previously described species, Sikkimia babai (Kimoto, 1989), comb. n., and four new species, Sikkimia meihuai sp. n., Sikkimia sufangae sp. n., Sikkimia tsoui sp. n., and Sikkimia yuae sp. n. Speciation models, supporting the high diversity of Sikkimia species in Taiwan, are discussed. Sikkimia metallica Jacoby, 1903 and Sikkimia tamra Maulik, 1936, both from southern India, are transferred to the genus Cerophysa Chevrolat, 1836.

Instituto de Investigaciones Agropecuarias y Forestales. Facultad de Biología. Facultad de Medicina Veterinaria y Zootecnia. Facultad de Agrobiología. Facultad de Químico Farmacobiología. Programa Institucional de Maestría en Ciencias Biológicas Antimicrobial peptides (PA) are widely distributed in the five kingdoms, its function is to protect living beings against pathogenic organisms. The development of biotechnology has allowed explore the effect of PA on animal pathogens using alternative systems for heterologous expression. Previous reports in the laboratory have shown that the use of bovine endothelium is an appropriate expression pattern PA plant. We assessed the antimicrobial capacity of the g-thionine of Capsicum chinense expressed by bovine endothelial cells, demonstrating its activity on the fungus Candida albicans and the tumor cell line HeLa (Anaya-Lopez et al., 2006a) and activity antimicrobial Thi2.1 of thionine Arabidopsis thaliana also expressed by endothelial cells, which is active against Gram-positive pathogenic bacteria, such as Staphylococcus aureus various cases of bovine mastitis (Ochoa-Zarzosa et al., 2008a), Gram negative pathogenic bacteria such as Escherichia coli, enteropathogenic (responsible for diarrhea in humans) against fungi such as C. albicans and to human tumor cells (Loeza-Angeles et al., 2008). In this sense, the use of PA represents a new strategy for treating infectious diseases, as an alternative to the indiscriminate use of antibiotics and consequently the selection of resistant to them (Brogden, 2005) strains. Recently it has been reported that PA as puroindolines wheat, magainin-2 frog and buforin frog, have antibacterial ability against intracellular pathogens (Takeshima et al., 2003; Capparelli et al., 2007; Imura et al., 2008). Los péptidos antimicrobianos (PA) están ampliamente distribuidos en los cinco reinos, su función es proteger a los seres vivos contra organismos patógenos. El desarrollo de la Biotecnología ha permitido explorar el efecto de los PA sobre microorganismos patógenos de animales empleando sistemas alternativos heterólogos para su expresión. Reportes previos en el laboratorio han mostrado que el empleo del endotelio bovino es un modelo adecuado de expresión de PA de plantas. Se ha evaluado la capacidad antimicrobiana de la g-tionina de Capsicum chinense, expresada por las células endoteliales bovinas, demostrándose su actividad sobre el hongo Candida albicans y la línea tumoral HeLa (Anaya-López et al., 2006a), así como la actividad antimicrobiana de la tionina Thi2.1 de Arabidopsis thaliana expresada también por células endoteliales, la cual presenta actividad contra bacterias patógenas Gram positivas, como lo son diversos aislamientos de Staphylococcus aureus de casos de mastitis bovina (Ochoa-Zarzosa et al., 2008a), bacterias patógenas Gram negativas como Escherichia coli enteropatogénica (responsables de diarreas en humanos), contra hongos como C. albicans y hacia células tumorales de humano (Loeza-Ángeles et al., 2008). En este sentido, el empleo de los PA representa una nueva estrategia de tratamiento de las enfermedades infecciosas, como alternativa al uso indiscriminado de antibióticos y en consecuencia a la selección de cepas resistentes a los mismos (Brogden, 2005). Recientemente se ha reportado que los PA como las puroindolinas del trigo, la magainina-2 de rana y la buforina de sapo, tienen capacidad antibacteriana en contra de patógenos intracelulares (Takeshima et al., 2003; Capparelli et al., 2007; Imura et al., 2008).

An Azospirillum strain from Cenchrus echinatus roots was isolated, and a pure culture of the strain was used as inoculum to induce root growth in Capsicum chinense seedlings. The inoculum concentration effects were evaluated on seeds germination rate, radicular system, and shoots growth. The inoculated seeds germination occurred a day before non inoculated seeds. An increase (P0.001) in terciary, and secondary root number, and in shoot growth was obtained. A significative difference of seedlings growth (P 0.01) in sterilized and non sterilized, soil was observed. The optimal inoculum size were 3 x 107 fcu ml-1 and 1 x 107 fcu ml-1. It is suggested that inoculum size has played an important role as modulator of indigenous microorganisms interactions.