Exploration of Phytochemicals Found in Terminalia sp. and their Antiretroviral Activities.

The human immunodeficiency virus (HIV) infects cells of the immune system and destroys their function. Approximately, 2 million people die every year from HIV as reported by the World Health Organization. HIV/AIDS is difficult to treat as the virus continuously develops resistance to drugs being developed. Approach is now turning toward natural products for the development of anti-HIV drugs. Although HIV/AIDS is not a new disease, but research based on plant-derived products is still under clinical trials. Experimentally, it has been proven that plants have the potential for HIV treatment. The process involves identification of the active ingredients responsible for the reported anti-HIV activities, testing of the extract, and development of appropriate bioassays. Further development would require optimization of the formulation and manufacturing in compliance with preclinical safety and efficacy testing. The most challenging task for the natural product scientists is to separate these highly complex extracts containing several compounds into its individual components that are biologically active. Recently developed direct binding assay with mass spectrometry (MS) technology (viz., real-time time-of-flight-MS) is helpful in this respect but needs extensive optimization. At present, we have compiled all the information for the various phytochemicals present in Terminalia catappa having anti-HIV properties. These include tannins, gallotannins, ellagitannins, cyanidin, and flavonoids. Further, we have also discussed their pharmacological as well as pharmacokinetics studies.

Cadamba: A miraculous tree having enormous pharmacological implications.

The Cadamba is one of the important medicinal plants belonging to the Rubiaceae family. It is crucially significant as it has the largest number of phytochemicals and secondary metabolites (viz., cadambagenic acid, cadamine, quinovic acid, ß-sitosterol, cadambine, etc.) having pharmacological and biological properties. It can be used as an alternative to various synthetic chemical compounds in the prevention as well as the treatment of several incurable diseases. More than 100 years of research has been done to discover various phytochemicals and their implications. Very few of them, i.e. ≤2% have been commercialized due to the lack of a suitable model system as well as various associated controversial issues. The solubility of phytochemicals is another major concern: Further response that will be generated due to the solvent used is also unpredictable. Moreover, the Cadamba is one of the ornamental plants with religious significance. Here we have made an effort to summarize all the phytochemicals and their significance to render the interest that would help in their commercialization.

Design, synthesis, and self-assembling properties of novel triazolophanes.

A series of novel triazolophanes containing peptidic and nonpeptidic backbones is reported. The crystal structure of one such macrocycle displays self-assembly through nonconventional hydrogen-bonding interactions.

Conserved subgroups and developmental regulation in the monocot rop gene family.

Rop small GTPases are plant-specific signaling proteins with roles in pollen and vegetative cell growth, abscisic acid signal transduction, stress responses, and pathogen resistance. We have characterized the rop family in the monocots maize (Zea mays) and rice (Oryza sativa). The maize genome contains at least nine expressed rops, and the fully sequenced rice genome has seven. Based on phylogenetic analyses of all available Rops, the family can be subdivided into four groups that predate the divergence of monocots and dicots; at least three have been maintained in both lineages. However, the Rop family has evolved differently in the two lineages, with each exhibiting apparent expansion in different groups. These analyses, together with genetic mapping and identification of conserved non-coding sequences, predict orthology for specific rice and maize rops. We also identified consensus protein sequence elements specific to each Rop group. A survey of ROP-mRNA expression in maize, based on multiplex reverse transcriptase-polymerase chain reaction and a massively parallel signature sequencing database, showed significant spatial and temporal overlap of the nine transcripts, with high levels of all nine in tissues in which cells are actively dividing and expanding. However, only a subset of rops was highly expressed in mature leaves and pollen. Intriguingly, the grouping of maize rops based on hierarchical clustering of expression profiles was remarkably similar to that obtained by phylogenetic analysis. We hypothesize that the Rop groups represent classes with distinct functions, which are specified by the unique protein sequence elements in each group and by their distinct expression patterns.