Determination of Bioactive Compound Kynurenic Acid in Linum usitatissimum L.

Kynurenic acid (KYNA) is a bioactive compound exhibiting multiple actions and positive effects on human health due to its antioxidant, anti-inflammatory and neuroprotective properties. KYNA has been found to have a beneficial effect on wound healing and the prevention of scarring. Despite notable progress in the research focused on KYNA observed during the last 10 years, KYNA's presence in flax (Linum usitatissimum L.) has not been proven to date. In the present study, parts of flax plants were analysed for KYNA synthesis. Moreover, eight different cultivars of flax seeds were tested for the presence of KYNA, resulting in a maximum of 0.432 µg/g FW in the seeds of the cultivar Jan. The level of KYNA was also tested in the stems and roots of two selected flax cultivars: an oily cultivar (Linola) and a fibrous cultivar (Nike). The exposure of plants to the KYNA precursors tryptophan and kynurenine resulted in higher levels of KYNA accumulation in flax shoots and roots. Thus, the obtained results indicate that KYNA might be synthesized in flax. The highest amount of KYNA (295.9 µg/g dry weight [DW]) was detected in flax roots derived from plants grown in tissue cultures supplemented with tryptophan. A spectroscopic analysis of KYNA was performed using the FTIR/ATR method. It was found that, in tested samples, the characteristic KYNA vibration bands overlap with the bands corresponding to the vibrations of biopolymers (especially pectin and cellulose) present in flax plants and fibres.

Effect of Yarrowia lipolytica yeast biomass with increased kynurenic acid content on selected metabolic indicators in mice.

Background: The unconventional yeast species Yarrowia lipolytica is a valuable source of protein and many other nutrients. It can be used to produce hydrolytic enzymes and metabolites, including kynurenic acid (KYNA), an endogenous metabolite of tryptophan with a multidirectional effect on the body. The administration of Y. lipolytica with an increased content of KYNA in the diet may have a beneficial effect on metabolism, which was evaluated in a nutritional experiment on mice. Methods: In the dry biomass of Y. lipolytica S12 enriched in KYNA (high-KYNA yeast) and low-KYNA (control) yeast, the content of KYNA was determined by high-performance liquid chromatography. Then, proximate and amino acid composition and selected indicators of antioxidant status were compared. The effect of 5% high-KYNA yeast content in the diet on the growth, hematological and biochemical indices of blood and the redox status of the liver was determined in a 7-week experiment on adult male mice from an outbred colony derived from A/St, BALB/c, BN/a and C57BL/6J inbred strains. Results: High-KYNA yeast was characterized by a greater concentration of KYNA than low-KYNA yeast (0.80 ± 0.08 vs. 0.29 ± 0.01 g/kg dry matter), lower content of crude protein with a less favorable amino acid composition and minerals, higher level of crude fiber and fat and lower ferric-reducing antioxidant power, concentration of phenols and glutathione. Consumption of the high-KYNA yeast diet did not affect the cumulative body weight gain per cage, cumulative food intake per cage and protein efficiency ratio compared to the control diet. A trend towards lower mean corpuscular volume and hematocrit, higher mean corpuscular hemoglobin concentration and lower serum total protein and globulins was observed, increased serum total cholesterol and urea were noted. Its ingestion resulted in a trend towards greater ferric-reducing antioxidant power in the liver and did not affect the degree of liver lipid and protein oxidation. Conclusions: The improvement of the quality of Y. lipolytica yeast biomass with increased content of KYNA, including its antioxidant potential, would be affected by the preserved level of protein and unchanged amino acid profile. It will be worth investigating the effect of such optimized yeast on model animals, including animals with metabolic diseases.

Honey's Yeast-New Source of Valuable Species for Industrial Applications.

Honey is a rich source of compounds with biological activity; moreover, it is a valuable source of various microorganisms. The aim of this study was to isolate and identify yeast from a sample of lime honey from Poland as well as to assess its ability to biosynthesize value-added chemicals such as kynurenic acid, erythritol, mannitol, and citric acid on common carbon sources. Fifteen yeast strains belonging to the species Yarrowia lipolytica, Candida magnolia, and Starmerella magnoliae were isolated. In shake-flask screening, the best value-added compound producers were chosen. In the last step, scaling up of the culture in the bioreactor was performed. A newly isolated strain of Y. lipolytica No. 12 produced 3.9 mg/L of kynurenic acid growing on fructose. Strain Y. lipolytica No. 9 synthesized 32.6 g/L of erythritol on technical glycerol with a low concentration of byproducts. Strain Y. lipolytica No. 5 produced 15.1 g/L of mannitol on technical glycerol, and strain No. 3 produced a very high amount of citric acid (76.6 g/L) on technical glycerol. In conclusion, to the best of our knowledge this is the first study to report the use of yeast isolates from honey to produce valuable chemicals. This study proves that natural products such as lime honey can be an excellent source of wild-type yeasts with valuable production properties.

The microbial production of kynurenic acid using Yarrowia lipolytica yeast growing on crude glycerol and soybean molasses.

Yarrowia lipolytica yeast are able to produce kynurenic acid-a very valuable compound acting as a neuroprotective and antioxidant agent in humans. The recent data proved the existence of the kynurenine biosynthesis pathway in this yeast cells. Due to this fact, the aim of this work was to enhance kynurenic acid production using crude glycerol and soybean molasses as cheap and renewable carbon and nitrogen sources. The obtained results showed that Y. lipolytica GUT1 mutants are able to produce kynurenic acid in higher concentrations (from 4.5 mg dm-3 to 14.1 mg dm-3) than the parental strain (3.6 mg dm-3) in the supernatant in a medium with crude glycerol. Moreover, the addition of soybean molasses increased kynurenic acid production by using wild type and transformant strains. The A-101.1.31 GUT1/1 mutant strain produced 17.7 mg dm-3 of kynurenic acid in the supernatant during 150 h of the process and 576.7 mg kg-1 of kynurenic acid in dry yeast biomass. The presented work proves the great potential of microbial kynurenic acid production using waste feedstock. Yeast biomass obtained in this work is rich in protein, with a low content of lipid, and can be a healthy ingredient of animal and human diet.

Wound coverage by the linen dressing accelerates ulcer healing.

INTRODUCTION: Chronic ulcers are the main cause of morbidity and mortality, and the incidence of chronic wounds is expected to increase given that people live longer and that there are civil diseases. AIM: Much attention in the treatment of wounds concerns a dressing that involves wound cleansing, bacterial balance, exudate management and local tissue in a wound environment. These important elements of the evaluation led to the development of an interactive dressing based entirely on flax raw materials. MATERIAL AND METHODS: The complete dressing for wound coverage was prepared from plant (flax) row products: seedcakes, oil, fiber. The content of bioactive compounds (qualitatively and quantitatively) was tested using chromatographic techniques, and their biological activity during tests on fibroblast cell cultures (NHDF). As a final step the clinical trial were performed. RESULTS: The dressings, which help control the microenvironment, combining with exudate using hydrophilic fibre, controlling the flow of exudate from the wound to the dressing were generated. They stimulate the activity in the healing cascade and accelerate the healing process by combining lignocellulose fibre with higher amounts of phenolic compounds, sterols, cannabidiol and unsaturated fatty acids simultaneously with the 3-hydroxybutyrate polymer. All constituents of linen dressing are natural, originate from two types of the engineered flax plant. Pre-clinical data reveal a reasonable reduction in wound size in patients with chronic leg ulcers treated with a linen dressing. CONCLUSIONS: For the first time, a successful application of the innovative interactive linen dressing in the treatment of chronic wounds was noted.

An efficient method for production of kynurenic acid by Yarrowia lipolytica.

Kynurenic acid (KYNA) is a compound derived from the tryptophan catabolic pathway. Antioxidant and neuroprotective properties have been confirmed for KYNA, which makes it an interesting and important metabolite of biomedical significance. In the present study, the yeast Yarrowia lipolytica was tested for KYNA biosynthesis. The results showed that Y. lipolytica strain S12 is able to produce KYNA in high concentrations (up to 21.38 µg/ml in culture broth and 494.16 µg/g cell dry weight in biomass) in optimized conditions in a medium supplemented with tryptophan. Different conditions of culture growth, including the source of carbon, its concentration and pH value of the medium, as well as the influence of an inhibitor or precursor of KYNA synthesis, were analysed. The obtained data confirmed the presence of KYNA metabolic pathway in the investigated yeast. To our best knowledge, this is the first study that reports KYNA production in the yeast Y. lipolytica in submerged fermentation.

Effect of mcl-PHA synthesis in flax on plant mechanical properties and cell wall composition.

The high demand for new biomaterials makes synthesis of polyhydroxyalkanoates (PHA) in plants an interesting and desirable achievement. Production of polymers in plants is an example of application of biotechnology for improving the properties of plants, e.g. industrial properties, but it can also provide knowledge about plant physiology and metabolism. The subject of the present study was an industrially important plant: flax, Linum usitatissimum L., of a fibre cultivar (cv Nike). In the study the gene encoding PHA synthase from Pseudomonas aeruginosa, fused to a peroxisomal targeting signal, was expressed in flax plants with the aim of modifying the mechanical properties of plants. Medium-chain-length (mcl) hydroxy acids in flax plants from tissue cultures were detected by GC-FID and FTIR method. The introduced changes did not affect fatty acid content and composition in generated flax plants. Since mcl-PHA are known as elastomers, the mechanical properties of created plants were examined. Modified plants showed increases in the values of all measured parameters (except strain at break evaluated for one modified line). The largest increase was noted for tensile stiffness, which was 2- to 3-fold higher than in wild-type plants. The values estimated for another parameter, Young's modulus, was almost at the same level in generated flax plants, and they were about 2.7-fold higher when compared to unmodified plants. The created plants also exhibited up to about 2.4-fold higher tensile strength. The observed changes were accompanied by alterations in the expression of selected genes, related to cell wall metabolism in line with the highest expression of phaC1 gene. Biochemical data were confirmed by spectroscopic methods, which also revealed that crystallinity index values of cellulose in modified flax plants were increased in comparison to wild-type flax plants and correlated with biomechanical properties of plants.

Impact of CAD-deficiency in flax on biogas production.

Global warming and the reduction in our fossil fuel reservoir have forced humanity to look for new means of energy production. Agricultural waste remains a large source for biofuel and bioenergy production. Flax shives are a waste product obtained during the processing of flax fibers. We investigated the possibility of using low-lignin flax shives for biogas production, specifically by assessing the impact of CAD deficiency on the biochemical and structural properties of shives. The study used genetically modified flax plants with a silenced CAD gene, which encodes the key enzyme for lignin synthesis. Reducing the lignin content modified cellulose crystallinity, improved flax shive fermentation and optimized biogas production. Chemical pretreatment of the shive biomass further increased biogas production efficiency.

New biocomposites based on bioplastic flax fibers and biodegradable polymers.

A new generation of entirely biodegradable and bioactive composites with polylactic acid (PLA) or poly-ε-caprolactone (PCL) as the matrix and bioplastic flax fibers as reinforcement were analyzed. Bioplastic fibers contain polyhydroxybutyrate and were obtained from transgenic flax. Biochemical analysis of fibers revealed presence of several antioxidative compounds of hydrophilic (phenolics) and hydrophobic [cannabidiol (CBD), lutein] nature, indicating their high antioxidant potential. The presence of CBD and lutein in flax fibers is reported for the first time. FTIR analysis showed intermolecular hydrogen bonds between the constituents in composite PLA+flax fibers which were not detected in PCL-based composite. Mechanical analysis of prepared composites revealed improved stiffness and a decrease in tensile strength. The viability of human dermal fibroblasts on the surface of composites made of PLA and transgenic flax fibers was the same as for cells cultured without composites and only slightly lower (to 9%) for PCL-based composites. The amount of platelets and Escherichia coli cells aggregated on the surface of the PLA based composites was significantly lower than for pure polymer. Thus, composites made of PLA and transgenic flax fibers seem to have bacteriostatic, platelet anti-aggregated, and non-cytotoxic effect.

Osteogenic capacity of transgenic flax scaffolds.

The modification of flax fibers to create biologically active dressings is of undoubted scientific and practical interest. Flax fibers, derived from transgenic flax expressing three bacterial genes for the synthesis of poly-3-hydroxybutyric acid (PHB), have better mechanical properties than unmodified flax fibers; do not show any inflammation response after subcutaneous insertion; and have a good in vitro and in vivo biocompatibility. The aim of this study was to examine the applicability of composites containing flax fibers of genetically modified (M50) or non-modified (wt-Nike) flax within a polylactide (PLA) matrix for bone regeneration. For this, the mRNA expression of genes coding for growth factors (insulin-like growth factor IGF1, IGF2, vascular endothelial growth factor), for osteogenic differentiation (alkaline phosphatase, osteocalcin, Runx2, Phex, type 1 and type 2 collagen), and for bone resorption markers [matrix metalloproteinase 8 (MMP8), acid phosphatase type 5] were analyzed using quantitative real-time polymerase chain reaction. We found a significant elevated mRNA expression of IGF1 with PLA and PLA-wt-Nike composites. The mRNA amount of MMP8 and osteocalcin was significantly decreased in all biocomposite-treated cranial tissue samples compared to controls, whereas the expression of all other tested transcripts did not show any differences. It is assumed that both flax composites are able to stimulate bone regeneration, but composites from transgenic flax plants producing PHB showed faster bone regeneration than composites of non-transgenic flax plants. The application of these linen membranes for bone tissue engineering should be proved in further studies.

The survival and proliferation of fibroblasts on biocomposites containing genetically modified flax fibers: an in vitro study.

Natural fibers have long been used in several branches of industry. Nowadays, they are considered as composite materials in medicine with special focus on artificial tissue scaffolding, drug-release systems, cardiovascular patches and nerve cuffs. The purpose of this study has been to examine the in vitro biocompatibility of newly designed "green composites". Therefore, composites containing flax fibers from transgenic flax plants producing polyhydroxybutyrate (M50) and control (wt-NIKE) plants in a polylactid (PLA) or polycaprolactone (PCL) matrix were prepared and mice fibroblast viability and cytotoxicity determined after incubation for 12-48h and 3 weeks with those composites. After 24h and 48h, all green composites have a strong influence on cell viability and membrane stability without any differences among each other. The cell viability of treated cells is approximately 82.5-93% of those of untreated control cells, respectively. The increase in cytotoxicity ranged between 1.4 and 2.9 fold compared to untreated cells. After 3 weeks of incubation, no significant changes were detectable in the amount of dead and living cells between composite treated and untreated cells. In conclusion, the tested new "green composites" showed a good biocompatibility. The biocompatibility of composites from transgenic flax plant fibers producing PHB did not differ from composites of non-transgenic flax plant fibers.

Effects of genetic modifications to flax (Linum usitatissimum) on arbuscular mycorrhiza and plant performance.

Although arbuscular mycorrhizal fungi (AMF) are known for their positive effect on flax growth, the impact of genetic manipulation in this crop on arbuscular mycorrhiza and plant performance was assessed for the first time. Five types of transgenic flax that were generated to improve fiber quality and resistance to pathogens, through increased levels of either phenylpropanoids (W92.40), glycosyltransferase (GT4, GT5), or PR2 beta-1,3-glucanase (B14) or produce polyhydroxybutyrate (M50), were used. Introduced genetic modifications did not change the degree of mycorrhizal colonization as compared to parent cultivars Linola and Nike. Arbuscules were well developed in each tested transgenic type (except M50). In two lines (W92.40 and B14), a higher abundance of arbuscules was observed when compared to control, untransformed flax plants. However, in some cases (W92.40, GT4, GT5, and B14 Md), the mycorrhizal dependency for biomass production of transgenic plants was slightly lower when compared to the original cultivars. No significant influence of mycorrhiza on the photosynthetic activity of transformed lines was found, but in most cases P concentration in mycorrhizal plants remained higher than in nonmycorrhizal ones. The transformed flax lines meet the demands for better quality of fiber and higher resistance to pathogens, without significantly influencing the interaction with AMF.

Improved properties of micronized genetically modified flax fibers.

The aim of this study was to investigate the effect of micronization on the compound content, crystalline structure and physicochemical properties of fiber from genetically modified (GM) flax. The GM flax was transformed with three bacterial (Ralstonia eutropha) genes coding for enzymes of polyhydroxybutyrate (PHB) synthesis and under the control of the vascular bundle promoter. The modification resulted in fibers containing the 3-hydroxybutyrate polymer bound to cellulose via hydrogen and ester bonds and antioxidant compounds (phenolic acids, vanillin, vitexin, etc.). The fibers appeared to have a significantly decreased particle size after 20h of ball-milling treatment. Micronized fibers showed reduced phenolic contents and antioxidant capacity compared to the results for untreated fibers. An increased level of PHB was also detected. Micronization introduces structural changes in fiber constituents (cellulose, hemicellulose, pectin, lignin, PHB) and micronized fibers exhibit more functional groups (hydroxyl, carboxyl) derived from those constituents. It is thus concluded that micronization treatments improve the functional properties of the fiber components.

The influence of biocomposites containing genetically modified flax fibers on gene expression in rat skeletal muscle.

In many studies, natural flax fibers have been proven to be resistant and surgically suitable. Genetically modified flax fibers, derived from transgenic flax expressing three bacterial genes for the synthesis of poly-3-hydroxybutyric acid (PHB), have better mechanical properties than unmodified flax fibers. The aim of this study was to examine the biocompatibility of composites containing flax fibers from transgenic polyhydroxybutyrate producing (M50) and control (wt-NIKE) plants in a polylactide (PLA) matrix in rat Musculus latissimus dorsi. For this purpose, effects of biocomposites on the expression of growth factors and osteogenic differentiation, in particular the mRNA expression of vascular endothelial growth factor, insulin like growth factor 1, insulin like growth factor 2, collagen-1, collagen-2 and myostatin, were analyzed using quantitative RT-PCR. The biocomposites did not show any inflammation response after subcutaneous insertion. The results following subcutaneous insertion of PLA alone and PLA-M50 showed no significant changes on the gene expression of all tested genes, whereas PLA-wt-NIKE reduced the mRNA amount of myostatin, VEGFA and IGF2, respectively. It can be asserted that modified flax membranes with PHB and other organic substances have a good biocompatibility to the muscle and they do not disrupt the muscle function. Furthermore, composites from transgenic flax plants producing PHB did not differ from composites of non-transgenic flax plants.

Biochemical, mechanical, and spectroscopic analyses of genetically engineered flax fibers producing bioplastic (poly-beta-hydroxybutyrate).

The interest in biofibers has grown in recent years due to their expanding range of applications in fields as diverse as biomedical science and the automotive industry. Their low production costs, biodegradability, physical properties, and perceived eco-friendliness allow for their extensive use as composite components, a role in which they could replace petroleum-based synthetic polymers. We performed biochemical, mechanical, and structural analyses of flax stems and fibers derived from field-grown transgenic flax enriched with PHB (poly-beta-hydroxybutyrate). The analyses of the plant stems revealed an increase in the cellulose content and a decrease in the lignin and pectin contents relative to the control plants. However, the contents of the fibers' major components (cellulose, lignin, pectin) remain unchanged. An FT-IR study confirmed the results of the biochemical analyses of the flax fibers. However, the arrangement of the cellulose polymer in the transgenic fibers differed from that in the control, and a significant increase in the number of hydrogen bonds was detected. The mechanical properties of the transgenic flax stems were significantly improved, reflecting the cellulose content increase. However, the mechanical properties of the fibers did not change in comparison with the control, with the exception of the fibers from transgenic line M13. The generated transgenic flax plants, which produce both components of the flax/PHB composites (i.e., fibers and thermoplastic matrix in the same plant organ) are a source of an attractive and ecologically safe material for industry and medicine.

Poly-3-hydroxy butyric acid interaction with the transgenic flax fibers: FT-IR and Raman spectra of the composite extracted from a GM flax.

The FT-IR and FT-Raman studies have been performed on commercial 3-hydroxy-butyric acid, commercial poly-3-hydroxy butyric acid as well as poly-3-hydroxy butyric acid (PHB) produced by bacteria. The data were compared to those obtained for poly-3-hydroxy butyric acid extracted from natural and genetically modified flax. Genetically modified flax was generated by expression of three bacterial genes coding for synthesis of poly-3-hydroxy butyric acid. Thus transgenic flaxes were enhanced with different amount of the PHB. The discussion of polymer structure and vibrational properties has been done in order to get insight into differences among these materials. The interaction between the cellulose of flax fibers and embedded poly-3-hydroxybutyric acid has been also discussed. The spectroscopic data provide evidences for structural changes in cellulose and in PHB when synthesized in fibers. Based on this data it is suggesting that cellulose and PHB interact by hydrogen and ester bonds.

Improving retting of fibre through genetic modification of flax to express pectinases.

Flax (Linum usitatissimum L.) is a raw material used for important industrial products. Linen has very high quality textile properties, such as its strength, water absorption, comfort and feel. However, it occupies less than 1% of the total textile market. The major reason for this is the long and difficult retting process by which linen fibres are obtained. In retting, bast fibre bundles are separated from the core, the epidermis and the cuticle. This is accomplished by the cleavage of pectins and hemicellulose in the flax cell wall, a process mainly carried out by plant pathogens like filamentous fungi. The remaining bast fibres are mainly composed of cellulose and lignin. The aim of this study was to generate plants that could be retted more efficiently. To accomplish this, we employed the novel approach of transgenic flax plant generation with increased polygalacturonase (PGI ) and rhamnogalacturonase (RHA) activities. The constitutive expression of Aspergillus aculeatus genes resulted in a significant reduction in the pectin content in tissue-cultured and field-grown plants. This pectin content reduction was accompanied by a significantly higher (more than 2-fold) retting efficiency of the transgenic plant fibres as measured by a modified Fried's test. No alteration in the lignin or cellulose content was observed in the transgenic plants relative to the control. This indicates that the over-expression of the two enzymes does not affect flax fibre composition. The growth rate and soluble sugar and starch contents were in the range of the control levels. It is interesting to note that the RHA and PGI plants showed higher resistance to Fusarium culmorum and F. oxysporum attack, which correlates with the increased phenolic acid level. In this report, we demonstrate for the first time that over-expression of the A. aculeatus genes results in flax plants more readily usable for fibre production. The biochemical parameters of the cell wall components indicated that the fibre quality remains similar to that of wild-type plants, which is an important pre-requisite for industrial applications.

Lignin deficiency in transgenic flax resulted in plants with improved mechanical properties.

Flax (Linum usitatissimum L.) is a very important source of natural fibres used by the textile industry. Flax fibres are called lignocellulosic, because they contain mainly cellulose (about 70%), with hemicellulose, pectin and lignin. Lignin is a three-dimensional polymer with a high molecular weight, and it gives rigidity and mechanical resistance to the fibre and plant. Its presence means the fibres have worse elastic properties than non-lignocellulosic fibres, e.g. cotton fibres, which contain no lignin. The main aim of this study was to produce low-lignin flax plants with fibres with modified elastic properties. An improvement in the mechanical properties was expected. The used strategy for CAD down-regulation was based on gene silencing RNAi technology. Manipulation of the CAD gene caused changes in enzyme activity, lignin content and in the composition of the cell wall in the transgenic plants. The detected reduction in the lignin level in the CAD-deficient plants resulted in improved mechanical properties. Young's modulus was up to 75% higher in the generated transgenic plants (CAD33) relative to the control plants. A significant increase in the lignin precursor contents and a reduction in the pectin and hemicellulose constituents was also detected. A decrease in pectin and hemicellulose, as well as a lower lignin content, might lead to improved extractability of the fibres. However, the resistance of the transgenic lines to Fusarium oxysporum was over two-fold lower than for the non-transformed plants. Since Fusarium species are used as retting organisms and had been isolated from retted flax, the increased sensitivity of the CAD-deficient plant to F. oxysporum infection might lead to improved flax retting.

Engineering of PHB synthesis causes improved elastic properties of flax fibers.

Flax stem is a source of fiber used by the textile industry. Flax fibers are separated from other parts of stems in the process called retting and are probably the first plant fibers used by man for textile purposes (1). Nowadays flax cultivation is often limited because of its lower elastic property compared to cotton fibers. Thus the goal of this study was to increase the flax fiber quality using a transgenic approach. Expression of three bacterial genes coding for beta-ketothiolase (phb A), acetoacetyl-CoA reductase (phb B), and PHB synthase (phb C) resulted in poly-beta-hydroxybutyrate (PHB) accumulation in the plant stem. PHB is known as a biodegradable thermoplastic displaying chemical and physical properties similar to those of conventional plastics (i.e., polypropylene). The fibers isolated from transgenic flax plants cultivated in the field and synthesizing PHB were then studied for biomechanical properties. All measured parameters, strength, Young's modulus, and energy for failure of flax fibers, were significantly increased. Thus the substantial improvement in elastic properties of fibers from the transgenic line has been achieved. Since the acetyl CoA, substrate for PHB synthesis, is involved not only for energy production but also for synthesis of many cellular constituents, the goal of this study was also the analysis of those metabolites, which interfere with plant physiology and thus fiber quality. The analyzed plants showed that reduction in lignin, pectin, and hemicellulose levels resulted in increased retting efficiency. A significant increase in phenolic acids was also detected, and this was the reason for improved plant resistance to pathogen infection. However, a slight decrease in crop production was detected.