COMPARISON OF CELL WALL STRUCTURE OF DIFFERENT WESTERN BALKAN PLANT SPECIES AS A SOURCE FOR BIOFUELS

Understanding of composition and connections between the building macromolecules of plant biomass, such as cellulose, hemicellulose and lignin, is main key for their better utilization in biofuels industry. We compared four different plant species which are abundant in the region of the Western Balkans. We investigated the structure of the cell walls, as the main constituent of plant biomass, isolated from branches of softwood (Picea omorika (Pancic) Purkine), hardwood (Acer platanoides L.), maize stem (Zea mays L.) as examples of crop species, and Paulownia tomentosa tree as a fast-growing species with a huge biomass yield. For our investigation, we combined Fluorescence-detected linear dichroism (FDLD) method and X-ray Diffraction. We obtained data for anisotropy and crystallography which are a base for prediction of the best and appropriate plant species for easy deconstruction of its biomass. Our results show that Acer branch as a hardwood shows the highest anisotropy and the lowest crystallinity compared to the other species while Picea Omorika needles show opposite results as the lowest anisotropy and the higher crystallinity. The results for maize show that the stems are easier for utilization than leaves. The isolated cell walls from leaves of Paulownia tomentosa show similar results and good correlation between anisotropy and crystallinity, thus we can conclude that this plant is easy to use in biofuel industries

Development and validation of spectrofluorimetric and LC–MS/MS methods for the determination of hesperidin in human plasma and pharmaceutical forms

The spectrofluorometric method, based on fluorescence properties of aluminium (III)–hesperidin complex, for the determination of hesperidin in human plasma and pharmaceutical forms has been developed and validated. The complex shows strong emission in the presence of surfactant betain sulfonate SB 12 at 476 nm with excitation at 390 nm. Linearity range in pharmaceutical forms of hesperidin was 0.06 – 24.4 μg mL-1 with LOD 0.016 μg mL-1 and LOQ 0.049 μg mL-1. Recovery values in the range 99.3 – 99.7% indicate good accuracy of the method. A linear dependence of the intensity of fluorescence of the complex on the concentration of hesperidin in plasma was obtained in concentration range from 0.1 – 12.2 μg mL-1. The LOD was 0.032 μg mL-1 while LOQ was 0.096 μg mL-1. Recovery values were in the range 98.4 – 99.8%. The reliability of the method was checked by LC-MS/MS method for plasma samples and HPLC/UV method for tablets with direct determination of hesperidin after separation. Linearity range in determination of hesperidin in pharmaceutical forms was obtained in the range from 0.05 to 10.00 μg mL-1. The LOD was 0.01 μg mL-1 and LOQ was 0.03 μg mL-1. Linearity range in plasma determination of hesperidin was 0.02 – 10.00 μg mL-1 with LOD 0.005 μg mL-1 and LOQ 0.015 μg mL-1. Good agreement between two methods indicate the usability of the proposed spectroflurometric method for the simple, precise and accurate determination of hesperidin in clinical and quality control laboratories