The benefits of bioconversion of waste lignocellulose include not only energy, but also reducing the amount of stored organic waste. Lignocellulose is a material widely available and characterized by a high content of carbohydrates, it is characterized by a complex tructure, which makes it accessible to its individual components is difficult. Most of the lignocellulose pretreatment methods are methods mechanical, chemical and physicochemical, thanks to which the level of complexity is reduced lignocellulose. These processes, in combination with enzymatic hydrolysis, enable the so-called cellulose saccharification and hemicellulose to monosaccharides. One of the possibilities of processing biomass after pretreatment, in order to to obtain biofuels from it, is dark anaerobic digestion, which is the process by which it is obtained biohydrogen. Since dark fermentation microorganisms in the logarithmic growth phase in addition to the products gaseous gases, at the same time emit organic acids, e.g. acetic acid, an obvious method of disposal dark fermented broths appear to be photofermentation with green and purple sulfur bacteria. There are no reports of the effects of treatment by-products in the literature initial raw material for the course of the indicated dark fermentation and photofermentation processes. For biomass resistance lignin is responsible for fermentation processes. Delignification, i.e. lignin's extraction using chemical reagents causes the so-called swelling of biomass, lignin structure disturbances and v the consequence of an increase in the internal surface area in the lignocellulosic structure. This effect translates to increasing the availability of lignocellulosic fibers for cellulolytic enzymes or, in the case of a process single stage, for microorganisms. Lignin release into the solution is also associated with delignification and its derivatives, ie syringol and guaiacol derivatives [1]. According to the author's knowledge, research on releases of the listed substances by biological treatment are not published. Carrying out research on the pretreatment of lignocellulosic materials and on the potential arising in this process lignin derivatives will provide a better insight into the pretreatment mechanisms, which will contribute to the development scientific discipline, and will also constitute a solid basis for further scientific research carried out as part of scientific research at the Gdańsk University of Technology.