Genus Zanthoxylum as Sources of Drugs for Treatment of Tropical Parasitic Diseases.

The tropical parasitic infections account for more than 2 billion infections and cause substantial morbidity and mortality, and account for several million deaths every year. Majorly parasitic infections in humans and animals are caused by protozoa and helminths. Chronic infections in the host can cause retardation, impairment of cognitive skills, development in young children and weaken the immune system. The burden is felt to a greater extent in developing countries due to poverty, inaccessibility to medicines and resistance observed to drugs. Thus, human health continues to be severely harmed by parasitic infections. Medicinal plants have received much attention as alternative sources of drugs. Zanthoxylum genus has been used ethnobotanically as an antiparasitic agent and the phytoconstituents in Zanthoxylum, show a wide variety of chemical substances with proven pharmacological actions such as alkaloids (isoquinolines and quinolines responsible for antitumor activity, antimalarial, antioxidant and antimicrobial actions), lignans, coumarins (antibacterial, antitumour, vasodilatory and anticoagulant activities), alkamide (strong insecticidal properties, anthelminthic, antitussive and analgesic anti antimalarial property). Therefore, this article is an attempt to review the existing literature that emphasizes on potential of genus Zanthoxylum as a source of lead compounds for the treatment of parasitic diseases.

Influence of protic ionic liquids on hydration of glycine based peptides.

The structure of water, especially around the solute is thought to play an important role in many biological and chemical processes. Water-peptide and cosolvent-peptide interactions are crucial in determining the structure and function of protein molecules. In this work, we present the H-bonding analysis for model peptides like glycyl-glycine (gly-gly), glycine-ւ-valine (gly-val), glycyl-ւ-leucine (gly-leu) and triglycine (trigly) and triethylammonium based carboxylate protic ionic liquids (PILs) in aqueous solutions as well as for peptides in ∼0.2 mol·L-1 of aqueous PIL solutions in the spectral range of 7800-5500 cm-1 using Fourier transform near-infrared (FT-NIR) spectroscopy at 298.15 K. The hydration numbers for peptides and PILs were obtained using NIR method of simultaneous estimation of hydration spectrum and hydration number of a solute dissolved in water. The H-bond of water molecules around peptides and PILs are found to be stronger and shorter than those in pure liquid water. We observe that the hydration shell around zwitterions is a clathrate-like cluster of water in which ions entrap. Watery network analysis confirms that singly H-bonded species or NHBs changes to partial or distorted ice-like structures of water in the hydration shell of PILs. The overall water H-bonding in the hydration sphere of PILs increases in the order TEAF < TEAA < TEAG < TEAPy ≈ TEAP < TEAB. The influence of PILs on hydration behavior of peptides is explored in terms of H-bonding, cooperativity, hydrophobicity, water structural changes, ionic interactions etc.

In situ investigation of phosphonate retarder interaction in oil well cements at elevated temperature and pressure conditions.

The effect of a high-performance retarding additive in oil well cements was investigated under elevated temperature (165°C) and pressure (1000 psi) conditions via in situ synchrotron-based X-ray diffraction (XRD) and quasielastic neutron scattering (QENS) techniques. Under these temperature and pressure conditions, crystalline calcium silicate hydrates (C-S-H) are formed through the cement hydration process. From in situ XRD experiments, the retardation effect was observed by a change in the rate of the appearance of 11 Å tobermorites as well as a change in the rate of the α-C2SH generation and depletion. QENS analysis revealed that the retardation effect was related to the non-conversion of free water to chemical and constrained water components. A high presence of free water components was attributed to a decrease in 11 Å tobermorites along with slower consumption of the quartz and portlandite phases. Furthermore, QENS results infer that the water molecules experienced confinement in the restricted pore spaces. The retarder inhibited this initial water confinement by slowing the bulk diffusion of free water in the confined region.