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Background: Strobilanthes crispus (L.) Bremek (Acanthaceae) leaves are used traditionally in Malaysia, Thailand, and Indonesia for anti-diabetic, anti-lytic, diuretic, and laxative purposes. Herb-drug interactions may potentiate or antagonize the absorption and metabolism of drugs which may result in potential toxicity. The aim of the present study was to investigate the effect of juice, hot aqueous, cold aqueous and methanol extracts of S. crispus leaves on phase I cytochrome 3A4 (CYP3A4) and Cytochrome 2E1 (CYP2E1) and phase II human liver enzyme UDP-Glucuronosyl Transferase (UGT). Methods: The herb-drug interactions of the leaf extracts and juice were determined by specific enzyme activity of CYP isoforms with specific probe substrate using spectrophotometry. CYP3A4 activity was measured for aminopyrine specific metabolite (formaldehyde) at 415 nm. CYP2E1 activity was determined using p-nitrophenol specific metabolite (p-nitrocatechol) at 535 nm. UGT activity was quantified through the consumption of p-nitrophenol by UGT at 405 nm. Results: All the S. crispus preparations showed significant inhibition of CYP3A4 activity. Only the methanolic extract showed a significant inhibition in CYP2E1. All the S. crispus extracts showed a significant effect on UGT activation at the higher concentration (1000 ng/ml). Only the cold aqueous extract and the juice showed UGT inhibition at lower concentration (1 ng/ml). Conclusion: S. crispus preparations showed in-vitro drug-herb interaction effects on human liver microsomes. Therefore, there is a possibility of drug-herb interaction could occur with S. crispus leaves through its effect on CYP3A4. Inhibition of the herb extracts on CYP2E1 could show anticarcinogenesis effects. The potency of drugs that metabolized via UGT pathway may be affected when co-administered with S. crispus leaf preparations.

Hazelnut (Corylus cornuta) is good source of natural antioxidants. Natural antioxidants are very important in the food industry for preparation of functional foods. The aim of this study was to evaluate antimicrobial activity against selected bacteria and antiradical potency of ethyl acetate and methanol extracts of dehulled hazelnut kernel. Dried sample powder was extracted with ethyl acetate and methanol. The antimicrobial activity of the extracts on Streptococcus pneumonia, Klebsiella pneumonia and Candida albicans was evaluated by the disk diffusion method. Total phenolic content and antiradical potency of the extracts against 2,2-diphenyl-1-picryhydrazyl (DPPH) radical were determined. Fingerprints of the extracts were developed by using HPLC. Total phenolic content of the methanol and ethyl acetate extracts were 0.67 and 0.58 mg gallic equivalent/g, respectively. Minimum inhibition concentrations (MIC) of the methanol and ethyl acetate extracts on S. pneumonia were 0.15 mg/ml and 0.76 mg/ml. Similar MIC values of 100 mg/ml on K. pneumonia were obtained for each extract. The extracts were inactive against Candida albicans. Observation of bacteria under light microscope revealed lower cell count and morphology changes as compared to control. The extracts exhibited free radical scavenging activity against DPPH radical. Qualitative HPLC analysis of the extracts showed the presence of caffeic acid, gallic acid, and vanillic acid. This study shows that hazelnut has antimicrobial and antiradical activities hence, eating the nuts may help to prevent infectious diseases.

Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.