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Multidrug resistant bacteria are marching and winning. The entire human race is at risk and new, effective antibiotics are needed for survival. Several notable routines to develop novel antibiotics are briefly compared here and possible new strategies are proposed. Key words include but not limited to nanotechnology, metal nanoparticles, natural product, medicinal plants, folk medicine, ethnopharmacology, computer-based screening, synergistic antibacterial activity, genomics, peptides, inhibitor, and structure-based virtual screening.

We have developed a continuous-wave (CW) terahertz (THz) radiation source that is excited using a laser diode (LD). With this source, the radiation is generated via difference frequency generation (DFG) under non-collinear phase matching in gallium phosphide (GaP). A distributed feedback (DFB) LD and an external cavity laser diode (ECLD) were used as the excitation light sources, and these, together with a polarization maintaining (PM) ytterbium-doped fiber amplifier, had linewidths of less than 4 MHz. The narrow linewidth means that the THz radiation can be used for high resolution spectroscopy. As an example of this, the spectrum for a mixture of saturated water vapor and ethanol at room temperature was obtained, where the spectral absorption lines for water and ethanol at around 2.46 THz could be distinguished. Furthermore, the THz spectra of water vapor at different humidity levels were measured under normal atmospheric conditions. From these we obtained the dependences on humidity of the position of the absorption peak, its FWHM and the intensity of the water vapor absorption band due to the rotational transition of 4 32 ←4 23 . We also show the results for time-dependent THz spectra of water vapor in a vapor-liquid coexistence in a chamber at reduced pressure, where an absorption peak, probably due to an intermediate state of the water molecules, appeared around 2.585 THz just after reducing the pressure in the chamber.

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In barley plants , the disease detected as spot blotch is caused by Bipolaris sorokiniana, and is the most deleterious disease for the producers and the beer industry. For fungicides mediated control of this disease can cause risks to environment and human health. To eliminate these drawbacks, one of the methods considered is the use natural products. The purpose of the present study was to investigate the use of extract of leaves from Bauhinia variegata Link. and Opera ® fungicide (active ingredient: pyraclostrobin) for controlling Bipolaris sorokiniana in barley plants. In Brazil there are two species of Bauhinia are seen, namely Bauhinia forficata and B. variegate. Extracts from B. variegata didn't show fungitoxic action but B. forficata the action exist. The barley plant showed protection of 92 to 100% in local and systemic action. The chemical TLC assays showed the presence of phenols (rutin, coumaric acid, kaempferol) that can be related to a signal for activation of the defense responses against pathogen or mechanism of salicylic acid. Treatment with fungicide Opera ® gave another mechanism and have only 60% of protection.