An ancient solution to a modern problem

The dearth of new antibiotics and escalating emergence of multidrug resistant bacteria have created a global healthcare crisis and highlight the drastic need for novel antimicrobial agents. Complementary and alternative strategies including the investigation of ancient medicinals could address this problem. Natural clay minerals with a long history of medicinal and biomedical applications have become an interest due to their broad-spectrum antimicrobial activity. Such untapped natural sources may provide new therapeutic agents in the battle against infectious diseases in the post-antibiotic era.     

A karyological study of some Dianthus L. species (Caryophyllaceae) in Northeast of Iran

This study focuses on karyological investigation of four taxa of Dianthus (Caryophyllaceae) including D. crossopetalus, D. orientalis subsp. stenocalyx, D. orientalis subsp. gorganicus, and Dianthus sp. distributed in Northeast of Iran. The karyotype asymmetry/symmetry was evaluated using two methods: 1) CVCL (coefficient of variation of chromosome length) and CVCI (heterogeneity of the centromeric index); and 2) MCA (mean centromeric asymmetry). The karyotype asymmetry was also used to investigate the relationships among the taxa. Results obtained from the current study revealed that there are two different ploidy levels (2n = 2x = 30 and 2n = 4x = 60) among the investigated taxa. The indices CVCL and MCA described karyotype asymmetry correctly based on variation in chromosome length. Diagram of CVCL vs. MCA seems to be appropriate for karyological delimitation and taxonomic relationships among the Dianthus taxa under study. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The evolution of Dianthus polylepis complex (Caryophyllaceae) inferred from morphological and nuclear DNA sequence data: one or two species?

Dianthus polylepis complex consists of two already known endemic species, Dianthus polylepis and D. binaludensis, in Khorassan-Kopetdagh floristic province. The taxonomic position of these species has long been debated. The aim of the present study is to shed light on the evolutionary relationships of the members of the complex using morphological and molecular data. In morphological study, firstly, 56 vegetative and floral characters were measured on 33 specimens of the both species. Multivariate analyses were performed on 25 (out of 56) significantly discriminating morphological traits. In molecular study, we sequenced alleles obtained from a region between 2nd and 6th exons of the gene coding for the enzyme dihydroflavonol 4-reductase copy1 (DFR1). Morphological results show that most of a priori identified accessions were not grouped in a posteriori classification. It is difficult to discriminate D. polylepis from D. binaludensis in morphological continuum among the accessions. Results obtained from the molecular data indicated no monophyly for the members of the D. polylepis complex. Consistency between the morphological and molecular results shows that D. polylepis and D. binaludensis were not morphologically and molecularly well differentiated. Therefore, we propose a new combination as D. polylepis subsp. binaludensis.