The objective of this paper is to provide a comprehensive review of best practice in hyperspectral imaging. The paper starts to review the taxonomy of the different spectral imaging techniques together with their advantages and disadvantages. The appropriate selection of cameras and spectrographs and their figures of merit are discussed and a detailed description is given of how to qualify and calibrate a pushbroom imaging system for on-line and in-line control. Special emphasis is given to detection and avoidance of specular reflection which can severely distort quantification of the spectral response. Recommendations for an ideal Lambertian illumination are given and the effects of scatter and absorption are discussed when particulate systems are investigated. Here, first principles are introduced and strategies for how to separate scatter from absorption are developed. A simple method using the Kubelka and Munk approach is examined and separated scatter and pure absorption spectra are shown. The same procedure is applied to show the lateral distribution of the separated scatter and absorption properties of an active pharmaceutical ingredient embedded in an excipient. The terms penetration and information depth are discussed and an example of penetration depth profile over wavelengths is provided. Based on a good quality optical setup and a validated measurement procedure, a practical procedure is described to analyse the data cube using the chemometrics toolbox for hyperspectral imaging. Finally, a survey on selected applications demonstrates the future potential of hyperspectral imaging.

Pectin and lignin are both very important noncellulosic substances occurring in hemp fibers. The main task in preparing hemp fibers for textile applications is to remove these noncellulosic substances without damage to the fiber cellulose. Pectin and lignin in hemp before and after chemical processing are characterized by infrared spectroscopy. The influence of chemical processes, fiber regions, and alkaline boiling parameters on lignin and pectin removal are investigated in this paper. The results indicate that the alkaline boiling process is effective for removing pectin and lignin. There is no residual pectin in the fibers after the alkaline treatment, but there is a residual level of lignin. The concentration levels of both sodium hydroxide and sodium sulphite have significant effects on lignin removal, and there are variations in lignin properties and accessibility from the lower to the upper regions of the hemp stem.

Protein production under the control of lac operon regulatory elements using autoinduction is based on diauxic growth of Escherichia coli on lactose after consumption of more preferred carbon substrates. A novel simple and cost-effective defined autoinduction medium using a mixture of glucose, glycerol, and lactose as carbon substrate and NH(4)(+) as sole nitrogen source without any supplementation of amino acids and vitamins was developed for T7-based E. coli expression systems. This medium was successfully employed in 96-well microtiter plates, test tubes, shake flasks, and 15-L bioreactor cultivations for production of different types of proteins achieving an average yield of 500 mg L(-1) product. Cell-specific protein concentrations and solubility were similar as during conventional isopropyl β-D-1-thiogalactopyranoside induction using Luria-Bertani broth. However, the final yield of target proteins was about four times higher, as a higher final biomass was achieved using this novel defined autoinduction broth.

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The genus Chitinophaga (Flexibacter) [1] is well known as a producer of peptides with antibacterial activity. Only recently, elansolid A was isolated as the first macrolide antibiotic from Chitinophaga sancti (comb. nov. = new combination), strain GBF13. Remarkably, elansolid A occurred as two, stable, separable atropisomers, A1 (1) and A2 (1*). Detailed NMR studies combined with molecular modeling revealed that the atropisomerism is caused by the rigidity of two differently folded macrolide rings with either C7 or C6 "folded-in" the lactone ring. Importantly, the isomers differ in their biological activity. Whereas 1* showed antibiotic activity against Gram-positive bacteria in the range of 0.2-64 mg mL À1 and cytotoxicity against L929 mouse fibroblast cells with a value for IC 50 of 12 mg mL À1, the other atropisomer 1 was clearly less active.[2]Our observation of a metabolite production depedent on the cultivation conditions of Chitinophaga sancti and the unaccounted occurrence of elansolids B1 (3) and B2 (4), which are assumed to be artifacts from treatment with water or methanol, required an in-depth analysis. We now report on the isolation and characterization of two further unique metabolites of which the exceptional, polyketide-based quinone methide antibiotic elansolid A3 (2) constitutes the major fraction (Scheme 1).For the production of 2, C. sancti was cultivated under slightly acidic conditions (pH 5.85) in the presence of Amberlite XAD 16 resin. After 150 h the neutral adsorber resin along with the adhering cell mass was harvested by sieving and then immediately frozen at À30 8C.Rapid HPLC-UV-HRMS analysis of a fresh acetone extract from the XAD resin additionally revealed a more polar peak of 2 at R t 5.4 min. The elemental composition was determined to be C 37 H 48 O 6 , which is identical to 1 (R t 8.7 min) and 1* (R t 7.6 min). However, isomer 2 differed in the UV spectrum with a new band at 324 nm. During attempted workup under mild conditions, the isolation of this new metabolite (2) turned out to be impossible as it readily reacted with water or methanol, thus yielding elansolid variants 3 and 4.[2] Because pH control did not stabilize the new metabolite 2 sufficiently, an unorthodox isolation process had to be developed. Unexpectedly, the final workup procedure had to be performed by carefully avoiding any contact of the fermentation products with water; this was achieved by using nitrogen as inert gas and all chromatographic steps were limited to the use of dry aprotic organic solvents. The freeze-dried Amberlite XAD 16 was extracted with dry acetone and 2 was isolated by silica-gel column chromatography, which finally yielded about 10 mg of 2 per plate by thick-layer chromatography.The NMR spectra were recorded in dry [D 6 ]acetone (see the Supporting Information, Table S1) [3] and clearly showed[a] Dr.