Concentration Of Active Substance Research Articles

Enhancement of Active Substances in Astragali Radix Broth with Lactic Acid Bacteria Fermentation and the Promotion Role of Chlorella Growth Factor

Astragali Radix, a traditional Chinese herbal medicine widely used for its medicinal properties, is known to be rich in active components that possess various pharmacological effects. However, the effectiveness of microbial fermentation in enhancing the content of these active substances remains unclear. In this study, a microflora of lactic acid bacteria was used to ferment Astragali Radix, and the promoting effect of Chlorella Growth Factor (CGF) on the fermentation process was investigated so as to clarify the changes in major active compound content in the fermented Astragali Radix broth. Non-targeted metabolomic analysis based on ultra-high-performance liquid chromatography–mass spectrometry was conducted to analyze the differences in metabolites before and after fermentation. The results showed that the total polysaccharide, total flavonoid, and total saponin content in the fermented Astragali Radix broth increased by up to 51.42%, 97.76%, and 72.81% under the optimized conditions, respectively. Streptococcus lutetiensis was the dominant bacterial species during the fermentation process. There were significant differences in metabolites in the fermentation broth before and after fermentation, among which amino acids (such as L-Aspartyl-L-Phenylalanine, etc.) and saponin compounds (such as Cloversaponin I, Goyasaponin I, etc.) were the main upregulated metabolites, which can enhance the physiological functions of Astragali Radix fermentation broth. The CGF exhibited the ability to promote the increase of active substance content in the fermented Astragali Radix broth.

An Ionic Liquid Nanoparticles for Dermal Targeted Delivery and Effective Anti-wrinkle Treatment

BackgroundAging is a natural process that cannot be stopped but retarded. Hydroxypinacolone retinoate (HPR) is a potent anti-wrinkle agent, but with severe irritancy, low stability, and poor water solubility, making it hard to apply in cosmetics. Ionic liquid (IL), as a solvent, displayed improved transdermal efficiency. The role of nano-encapsulation technology in addressing the disadvantages of efficacy application is significant. ObjectiveUsing a combination of ionic liquids and nano-encapsulation technology to obtain HPR-encapsulated ionic liquid nanoparticles (HPR IL-NPs) is an innovative formulation used as a serum, emulsion, and cream in cosmetics for effective anti-wrinkle. MethodsHPR IL-NPs were prepared using matrine coconut oil ionic liquid as a surfactant and permeation enhancer combined with high-pressure homogenization. ResultsThe average particle size in the obtained HPR IL-NPs was 92.8 nm. Applying the HPR IL-NPs increased the content of active substances in the skin by 3.6-fold compared to a traditional HPR-loaded cream. The chick chorioallantois membrane assay showed an RC50 > 100%, and repeated skin-irritation tests resulted in a mean value of 0.00 points per animal per day. The HPR IL-NPs showed continuous release for 24 hours in vitro in the continuous release test. At the same time, the HPR IL-NPs significantly reduced irritation induced by HPR alone. The number and area of facial wrinkles decreased by 25.09% and 23.65%, respectively, after one week of application of liquid cream on volunteers. ConclusionIL NPs can significantly improve transdermal absorption efficiency, reduce irritation, and demonstrate high anti-wrinkle efficiency. Supramolecular liquid cream is a promising product in cosmetics for skin care.

Determination of antibacterial performance of boric acid ester in the paint industry

ABSTRACT This study aims to assess the antibacterial activity of boric acid ester derived from boron mines, which is utilised as an active component in the paint industry. Multiple product variations were obtained by adding boric acid ester to the base, referred to as the reference sample, known as silk matte paint, and used as an interior paint with active substance concentrations ranging from 0.005% to 0.6%. Escherichia coli (ATCC10536) bacteria were inoculated at 78000 cfu cm−2 into samples with 0.005- 0.075% active substance, and at 24000 cfu cm−2 into samples containing 0.15- 0.6% of the active substance, and the reduction rates were determined by a mathematical equation via multivariate linear regression analysis, relating Escherichia coli reduction percentages, surface energy values, and pH measurements, including the power percentages and gloss values for the reference sample. The highest level of antibacterial effect was observed in the sample containing 0.075% active substance.

Evaluation of Pre-Harvest Nutrient Composition and Functional Active Substances in Various Lotus Roots.

This study investigated the impact of variety and harvest time on the visual appearance, nutritional quality, and functional active substances of six lotus root cultivars: "Xinsanwu", "Wuzhi No. 2", "Baiyuzhan", "Huaqilian", "Elian No. 6", and "Elian No. 5". Samples were collected monthly from December 2023 to April 2024. A nutrient analysis revealed a decrease in the water content with a delayed harvest. The total soluble solids and soluble sugar content peaked towards the end and middle-to-late harvest periods, respectively. Starch levels initially increased before declining, while the soluble protein exhibited a triphasic trend with an initial rise, a dip, and a final increase. The vitamin C (Vc) content varied across cultivars. Functional active substances displayed dynamic changes. The total phenolics initially decreased, then increased, before ultimately declining again. The total flavonoid content varied by both cultivar and harvest time. The phenolic acid and flavonoid content mirrored the trends observed for total phenolics and total flavonoids. Gastrodin was the most abundant non-flavonoid compound across all varieties. "Wuzhi No. 2" and "Baiyuzhan" displayed higher levels of functional active substances and starch, while the Elian series and "Xinsanwu" cultivar exhibited a greater content of Vc, soluble sugar, and soluble protein. Specific harvest periods yielded optimal results: "Wuzhi No. 2" (H1 and H5), "Huaqilian" (H2), and "Baiyuzhan" (H3 and H4) demonstrated a high nutrient and functional active substance content. Overall, the lotus roots harvested in period H4 achieved the highest score. Overall, this study provides the foothold for the rapid identification of superior lotus root cultivars and the valorization of lotus root by-products via advanced processing methods. Additionally, it offers valuable insights for market participants and consumers to select optimal varieties and harvest times based on their specific needs.

Calculated Drug Concentrations in Currently Available Intravitreal Therapies: Determination of Dilution Factor and Deviation From Recommended Doses.

In ophthalmology, intravitreal therapies are currently not personalized/customized and are not adjusted to the individual vitreous volume. With reference to the recently published calculation formula for a more accurate estimation of the vitreous body, we determined the dose of intravitreal medication for different vitreous volumes and compared them with the average volume. Using the axial length of the eye, the formula for the vitreous volume exact (VIVEX) can provide a more accurate indication of the vitreous volume in individual cases than an assumed standard volume of 4 mL. The concentration of active substances in small eyes may be twice as high as that in normal-sized emmetropic eyes. In contrast, large eyes may show less than half of the recommended drug concentration. The calculated concentrations of the investigated intravitreal drugs in small and large eyeballs showed impressive differences with large deviations from the recommended doses. Further systematic studies should follow to find out whether this has any impact on the effectiveness or side effects of the injected drugs.

Cosmetic Education Regarding the Making and Use of Hair Serum in Teenagers to Young Adults

Indonesia is a relatively large market for the cosmetics industry in the hair care category. Teenagers and young adults are among the dominant segments in cosmetic consumption. Hair and scalp problems often experienced are hair loss and unhealthy hair structure. This problem can be overcome with hair serum. This dosage form is attractive because it can be purchased freely and is quite promising due to its high active substance content. Various types of hair serums are available on the market so that they can be adjusted based on user preferences. The high level of public consumption of hair serum needs to be balanced with education regarding hair serum. The education process uses lecture and workshop methods related to identifying hair problems, the nutrition needed by hair, and the types and formulation of hair serum. The workshop was conducted directly by involving participants in producing the hair serum. The educational process was attended by 24 students aged 19-22 years, 21% coming from outside Atma Jaya and 79% from internal Atma Jaya. Gender includes 19% of men and the rest of women. The educational process increased the understanding of 92% of participants, with an average score from 5.9 to 9.75. As many as 96% of participants were very interested and stated that this workshop supported the theory that had been given to make it easier to understand.

Literature Review: the Effect of Ajwa Dates on Hemoglobin Levels in Perimenopause Women

Ajwa dates or often called prophet dates are types of dates that grow in Saudi Arabia / Al-Madinah Al-Munawara and have significant value in healing several diseases. The content of active substances contained in date extracts such as vitamins B1, B2, nicotinic acid, vitamin complex A, magnesium, calcium and iron which has a function to help the formation of hemoglobin. Perimenopause is an indefinite period of time that surrounds the final years of a woman's reproductive life, usually between the ages of 30-40 years when estrogen levels slowly decline causing menstrual abnormalities. The decrease in estrogen levels in perimenopausal women causes excessive blood loss so that iron deficiency anemia will occur. Objective : To determine the effect of consumption of ajwa dates (Pheonix Dactylifera L) on hemoglobin levels in perimenopausal women. Method : Literature Review with Design Narrative review. Results : Based on the results of research from several literatures that discuss the effects of giving Ajwa Dates (Phoenix Dactylifera L) before and after administration, it shows that there are differences in hemoglobin levels. Especially in perimenopausal women who are prone to iron deficiency anemia because Ajwa dates contain high iron, which increases hemoglobin levels. So it is highly recommended for consumption. Conclusion : Ajwa Dates (Phoenix Dactylifera L) can increase hemoglobin levels in perimenopausal women.

Stability Studies of the Dilution Series of Different Antibiotic Stock Solutions in Culture Medium Incubated at 37 °C.

The long-term stability of antibiotics in culture media remains underexplored in scientific literature. This study evaluated the stability of eight distinct antibiotic stock solutions-amoxicillin, cefotaxime, neomycin, oxytetracycline, florfenicol, enrofloxacin, colistin, and potentiated sulfonamide-and their 10-fold dilution series in tryptone soy broth (TSB) at 37 °C, over 12 days. Samples were collected immediately after preparation and on days 1, 2, 5, 7, 9, and 12, with active substance concentrations measured using ultra-high-performance liquid chromatography (UHPLC) coupled with mass spectrometry. The results indicated that among the ultrapure water stock solutions, neomycin, florfenicol, and potentiated sulfonamide maintained stability (>95%). Within the culture medium, florfenicol showed consistent stability (100%) throughout the study, potentiated sulfonamide experienced minor degradation (>85%), and neomycin underwent significant degradation. Amoxicillin, oxytetracycline, and colistin displayed considerable degradation in both solution types but were more stable in ultrapure water solutions. The stability of cefotaxime and enrofloxacin in ultrapure water solutions and in the medium was very similar when compared; however, 3.6% of the former and 88.7% of the latter remained detectable by day 12. These findings are crucial for minimum inhibitory concentration (MIC) assessments, especially in minimum bactericidal concentration (MBC) studies, and in experiments concerning long-term evolution and co-selection. This study underscores the necessity of stability assessments in culture media to validate future experimental outcomes.

Screening of Anti-inflammatory and Antimicrobial activity on Flower Extracts of Morinda coreia Buch Ham.

Objectives: Morinda coreia has rich active components which has been used in folk medicine for the treatment of several diseases. Their active substance content may vary according to plant genetics, parts used,as well as to climatic factors, quality of the ground in which the plants were grown, the time of harvesting, and the extraction methods. Basically the flowers can heal the common cold, improve memory, aid relaxation due to presence of volatile oil. Flowers could be used as a new approach for the development of nutraceutical products or functional foods. The flower part of this plant are not documented. To develop and apply it, we report Pharmacological effects such as anti-inflammatory, antimicrobial activity. Methods: The extracts were prepared by cold maceration process with aqueous and organic solvents such as ethanol and ethyl acetate. The anti-inflammatory activity were evaluated using carrageenan-induced paw edema method and the antimicrobial activity by agar well diffusion method. Results: The maximum zone of inhibition for Bacillus subtilis was found to be more susceptible toward the ethanolic extract (14mm) at the maximum conc. of 300µl followed by ethyl acetate (10mm) and aqueous extract (12mm). Similarly for Klebsiella pneumonia maximum inhibitory zone (13mm) followed Pseudomonas auroginosa (13mm), Staphylococcus aureus (12mm), Candida albicans was moderate sensitive towards ethanolic extract (11mm) Conclusion: The ethanolic extract of Morinda coreia flower possessed high anti-inflammatory, antimicrobial activity than ethyl acetate and aqueous extracts on comparing with standards.

Неразрушающий контроль нестероидных противовоспалительных средств методом ИК-спектроскопии в ближней области

The use of near-infrared spectroscopy for quality control of nonsteroidal anti-inflammatory drugs (NSAIDs) in blister packs is demonstrated. NSAIDs with the active ingredients ibuprofen, diclofenac, naproxen, etoricoxib, acetylsalicylic acid and meloxicam have been studied. IR spectra have been recorded using a Frontier FTIR spectrometer with a NIRA attachment, used to collect diffuse reflectance spectra of solids. Processing and visualization of the study results has been carried out using chemometric algorithms – principal component analysis (PCA), hierarchical cluster analysis (HCA) and partial least squares regression (PLS). It is shown that using these algorithms it is possible to identify drugs by their manufacturer and determine the concentration of active substances. In the PCA method, the points corresponding to the samples of the analyzed tablets are located in separate quadrants depending on their manufacturer. The use of hierarchical cluster analysis (HCA) made it possible not only to differentiate the analyzed tablets by manufacturer, but also to determine the content of the active substance in them. “Measured-predicted” calibration models have been constructed, the values of the root mean square residual of calibration (RMSEC) did not exceed 6.28 mg. The relative discrepancies between the values obtained during the analysis and those assigned correspond to the permissible deviations established by order of the Ministry of Health of the Russian Federation dated October 26, 2015 no. 751n. The duration of the analysis was 7–10 min.

Sb-doped tin oxide nanonets for improved conductivity in transparent conductive coatings

In light of the three primary challenges faced by transparent conductive coatings, namely poor conductivity, elevated the active substance content, and insufficient visible light transmittance, net-like conductive agents due to the unique morphology and structure have been developed to address these concerns simultaneously. A straightforward synthesis of antimony-doped tin oxide (ATO) nanonets was accomplished through a simple two-step coprecipitation and hydrothermal methods. Firstly, an antimony-doped stannic hydroxide hydrogel precursor was generated through coprecipitation. Secondly, by adjusting the pH value in the hydrothermal reaction, ATO nanocrystals network were obtained without the need for additional materials. The synthesized ATO, with a net-like morphology, comprises particles of approximately 3–5 nm in diameter. Throughout the reaction, ammonium hydroxide, used as a pH regulator, played a vital role as a reducing agent in forming ATO nanonets without the need for further post-treatment. Moreover, net-like ATO compounded with SiO2 transparent conductive coatings exhibited exceptional transparent conductive properties, with a visible-light transmittance of approximately 84.7 % at the wavelength of 550 nm and a square resistance of 0.5 kΩ/sq upon spin-coating deposition on glass. This remarkable performance can be attributed to the generation of a continuous conductive network. In comparison to granular ATO, the network structure ATO nanocrystal showcases a significant improvement in resistivity, demonstrating its exemplary transparent conductivity. The approach for the preparation of ATO nanonets was simple and easy to scale up to provide an enormous potential and broad prospect for the application of net-like ATO in transparent conductive coating.

Inhibition of LPS-Induced Skin Inflammatory Response and Barrier Damage via MAPK/NF-κB Signaling Pathway by Houttuynia cordata Thunb Fermentation Broth.

Houttuynia cordata Thunb is rich in active substances and has excellent antioxidant and anti-inflammatory activity. Scanning electron microscopy and gel permeation chromatography were used to analyze the molecular characteristics of the fermentation broth of Houttuynia cordata Thunb obtained through fermentation with Clavispora lusitaniae (HCT-f). The molecular weight of HCT-f was 2.64265 × 105 Da, and the polydispersity coefficient was 183.10, which were higher than that of unfermented broth of Houttuynia cordata Thunb (HCT). By investigating the active substance content and in vitro antioxidant activity of HCT-f and HCT, the results indicated that HCT-f had a higher active substance content and exhibited a superior scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radicals and hydroxyl radicals, with IC50 values of 11.85% and 9.01%, respectively. Our results showed that HCT-f could effectively alleviate the increase in the secretion of inflammatory factors and apoptotic factors caused by lipopolysaccharide (LPS) stimulation, and had a certain effect on repairing skin barrier damage. HCT-f could exert an anti-inflammatory effect by down-regulating signaling in the MAPK/NF-κB pathway. The results of erythrocyte hemolysis and chicken embryo experiments showed that HCT-f had a high safety profile. Therefore, this study provides a theoretical basis for the application of HCT-f as an effective ingredient in food and cosmetics.

Nanobubbles improve peroxymonosulfate-based advanced oxidation: High efficiency, low toxicity/cost, and novel collaborative mechanism

Cl- activated peroxymonosulfate (PMS) oxidation technology can effectively degrade pollutants, but the generation of chlorinated disinfection byproducts (DBPs) limits the application of this technology in water treatment. In this study, a method of nanobubbles (NBs) synergistic Cl-/PMS system was designed to try to improve this technology. The results showed the synergistic effects of NBs/Cl-/PMS were significant and universal while its upgrade rate was from 12.89% to 34.97%. Moreover, the synergistic effects can be further improved by increasing the concentration and Zeta potential of NBs. The main synergistic effects of NBs/Cl-/PMS system were due to the electrostatic attraction of negatively charged NBs to Na+ from NaCl, K+ from PMS, and H+ from phenol, which acted as a "bridge" between Cl- and HSO5- as well as phenol and Cl-/HSO5-, increasing active substance concentration. In addition, the addition of NBs completely changed the oxidation system of Cl-/PMS from one that increases environmental toxicity to one that reduces it. The reason was that the electrostatic attraction of NBs changed the active sites and degradation pathway of phenol, greatly reducing the production of highly toxic DBPs. This study developed a novel environmentally friendly oxidation technology, which provides an effective strategy to reduce the generation of DBPs in the Cl-/PMS system.

Variation of the Content and Antioxidant Activity of Active Substances in the Kombucha Fermentation of Mulberry Leaves

With the increasing emphasis on healthy living, Kombucha beverages are becoming more and more popular. Recently, fermented Kombucha with different materials and investigated the efficacy have become hot topics. In this paper, mulberry leaves were used as substrates for Kombucha fermentation. The active substances contents and antioxidant activities of the fermented mulberry leaf infusion were significantly enhanced. After being fermented for 10 days, the total phenolic substances and total flavonoids in the Kombucha fermented mulberry leaf infusion were 7.38 and 12.24 times higher than those in the unfermented mulberry leaf infusion, respectively. While the mulberry leaf infusion that fermented for 6 days had the highest antioxidant capacity. The Ferric (Fe3+) reducing power, ABTS+ radical scavenging capacity, and hydroxyl radical (·OH) scavenging capacity were enhanced by 90.3%, 21.82%, and 46.2%, respectively. In conclusion, after being fermented by Kombucha, the antioxidant properties of mulberry leaf infusion were significantly improved, which will contribute to expanding the subsequent development and application of mulberry leaf.

Analysis of the Impact of Black Tea Waste on The Fertility Quality of Rainbow Chili Plants (Capsicum annum L.)

Black tea is a drink commonly consumed in Indonesia, so it is not uncommon for dregs to be found to be wasteful. Waste is a serious problem that, if not handled properly, will have specific environmental impacts. Many people use tea waste as fertilizer without knowing the danger it causes to plants without further processing. This research aimed to analyze the effects of black tea waste on the fertility quality of rainbow chili plants (Capsicum annum L.). The type of research is qualitative research. The method used in this research is qualitative observation to observe the maximum height, the time to reach the maximum height, the entire leaf width, the time when the first flower appears, the time when the first fruit appears when the first fruit matures, the length of the first fruit, and the middle circumference of the first fruit of the rainbow chili plants (Capsicum annum L.) which were planted in potting soil given black tea waste with different ratio. From all the parameters observed, it was found that the best quality of rainbow chili plants (Capsicum annum L.) was in potting soil with a definite ratio of not too much but also not too little. From this fact, black tea waste can fertilize plants, but with a specific maximum level limit. Excessive amounts of tea waste can trigger alkalinity in the soil, which reduces plant fertility, and the presence of active substances such as polyphenols in it can kill decomposing bacteria, which causes new problems for the soil. Further research is still needed, especially in overcoming alkalinity and the content of active substances that can kill decomposing bacteria in the soil in black tea waste before it can be made into a commercial product like planting medium.

Development and validation of an analytical method for acetamiprid determination in plant protection products using HPLC-DAD

AbstractPlant protection products (PPP), crucial for agricultural production, are experiencing increased global demand, particularly with the growing need for food production. To meet this demand, robust analytical methods are essential for confirming the presence and determining active substance concentrations in PPP. This study introduces an analytical method utilizing high-performance liquid chromatography with a diode array detector (HPLC-DAD) for determination of acetamiprid in water-soluble powder formulations. The method, validated according to SANCO/3030/99 rev.5, demonstrated exhibited adequate accuracy and precision, with repeatability expressed as the ratio of the standard deviation (% RSD) to the relative standard deviation (% RSDr) being lower than 1. Recoveries for the active substance at concentrations above 10% ranged from 97% to 103%. The developed method is also characterized by suitable linearity, confirmed by a correlation coefficient >0.99. Specific chromatographic profiles were generated, and acetamiprid content in 180 formulations was analyzed, including reference products. The developed method aligns with “green chemistry” principles, minimizing solvent use and emphasizing energy efficiency. Overall, it offers a comprehensive approach for qualitative and quantitative analysis, ensuring the reliability of PPP quality control.

Epigallocatechin-3-gallate protects sepsis‐induced myocardial dysfunction by inhibiting the nuclear factor-κB signaling pathway

Sepsis-induced myocardial dysfunction (SIMD) has become one of the most lethal complications of sepsis, while the treatment was limited by a shortage of pertinent drugs. Epigallocatechin-3-gallate (EGCG) is the highest content of active substances in green tea, and its application in cardiovascular diseases has broad prospects. This study was conducted to test the hypothesis that EGCG was able to inhibit lipopolysaccharide (LPS) induced myocardial dysfunction and investigate the underlying molecular mechanisms. The cardiac systolic function was assessed by echocardiography. The cardiomyocyte apoptosis was determined by TUNEL staining. The expression of inflammatory factors and apoptosis-related protein, cardiac markers were examined by Western Blot and qRT-PCR. EGCG effectively improve LPS-induced cardiac function damage, enhance left ventricular systolic function, and restore myocardial cell vitality. It can effectively inhibit the upregulation of TLR4 expression induced by LPS and inhibit IκB α/NF- κB/p65 signaling pathway, thereby inhibiting cardiomyocyte apoptosis and improving myocarditis. In conclusion, EGCG protects against SIMD through anti-inflammatory and anti-apoptosis effects; it was mediated by the inhibition of the TLR4/NF-κB signal pathway. Our results demonstrated that EGCG might be a possible medicine for SIMD prevention and treatment.

Analysis of some trends of the pharmaceutical market of rodenticides in Ukraine and the peculiarities of their use for deratization

Analysis of some trends of the pharmaceutical market of rodenticides in Ukraine and the peculiarities of their use for deratization

Effect of integrated use of Zircon and Siliplant on productivity of <i>Echinacea purpurea</i> roots in Western Caucasus

Echinacea purpurea L. – is a perennial medicinal plant, from the herb of which dozens of preparations have been created that are used to strengthen the immune system, in the treatment of inflammatory diseases. At present, oxyconic acids and alkamides have been found in the plant’s root system, and the preparations «Anginol» and «Prostanov» have been created on their basis. The production and creation of new medicinal products from the roots and rhizomes of the Echinacea purpurea depends on a stable raw material base, which can be ensured by obtaining maximum yields of roots. As a result of studies to determine the timing of harvesting, methods to increase the yield of the underground mass in the conditions of the Krasnodar Territory, it was revealed that the high yield of roots and rhizomes of Echinacea purpurea was determined on plantations III-IV years of growing, which averaged 10 c/ha, they had an oxyconic acid content of 3,9%. In the future, there is a decrease in yield to 8 c/ha, and active substances to 2.1%. Dual treatments treatments Zircon (0.04 l/ha) and Siliplant (0.5 l/ha) both separately and in the mixture gave the opportunity to increase the yield for III and IV years to 28–30% and improve the quality of raw materials, the content of active substances increased by 5–7%. The complex use of these drugs in the V year of vegetation allows to increase the yield of roots to 10.3 c/ha with a high content of oxidic acids – 2.55%. It was revealed that foliar fertilization of vegetative plants with two-component system Siliplant + Zircon promotes the adaptation of Echinacea purpurea to dry weather conditions and makes it possible to obtain stable yields of medicinal raw materials with high quality regardless of weather conditions.

The Effect of Drought on the Content of Active Substances of Flax Fibers

ABSTRACT The aim of the research was to identify differences in the content of phenolic acids in flax fibers and antioxidant activity of the fibers depending on the soil moisture level during plant growth and flax variety. The experiment involved cultivating flax under controlled conditions with constant levels of irrigation: 25%, 35%, and 45% of field water capacity (FWC). The experiment conducted in the vegetative hall of the Institute of Natural Fibers and Medicinal Plants, National Research Institute in Poland was repeated three times: in 2019, 2020, and 2021. The fibers were extracted from the straw with use of dew retting method. Flax fibers exhibit biological activity. In current study, the impact of drought during flax growth on the antioxidant activity of fibers was determined, as bioactive fibers of linen clothing touching the skin can contribute to neutralizing free radicals formed next to human body. The antioxidant activity of tested fibers was examined using DPPH and FRAP methods. The quantity of phenolic acids may affect the antioxidant capacity of the fibers. The research results showed that the cultivation of flax plants at a soil moisture level of 45% FWC favors the development of antioxidant activity in the fibers.