Search Results (62)

Due to its health-promoting properties, resveratrol is one of the most desirable compounds in many industries. Hence, this work focused on finding the conditions of its extraction from Japanese knotweed which could be used on an industrial scale to obtain extracts with the best antioxidant properties. The contribution of polyphenolics to the activity of the obtained isolates was also assessed in this study. Ultrasound-assisted solvent extraction was used to prepare extracts in various solvents under conditions differing in extraction time, temperature, and ultrasound frequency. The extracts were tested for their ability to neutralize radicals and reduce metal ions. It was shown that although the best extractant was the same water–alcohol mixture, the optimal conditions for the extraction of resveratrol and polyphenols were different: 10 min, 50 °C and 80 kHz for resveratrol (for which the highest contents of resveratrol equals 0.91 mg/g was obtained) and 20 min, 25 °C and 37 kHz for polyphenolics (for which the total phenolic content equals 31.28 mg of gallic acid/g was determined) Under the latter conditions, one of the best antioxidant activities was also obtained. The results confirm that Japanese knotweed, despite its bad reputation in Europe as a very invasive species, can be used as a source of sought-after resveratrol and polyphenols. Full article

Background/Objectives: Gingipains produced by P. gingivalis have been shown to be directly related to periodontal tissue degradation and are significant molecular targets in therapy of periodontitis. Blocking the activity of these enzymes should reduce survival of this pathogen and mitigate the effects of inflammation in periodontitis. Therefore, gingipains inhibitors and specific antibodies could be recommended in the treatment of periodontitis. Cysteine peptidase inhibitors can be obtained by chemical synthesis, or isolated from natural raw materials. This research has the following aims: 1. to analyze in vitro the inhibition of cysteine protease activity in the gingival crevicular fluid (GCF) and 2. to compare the toxicity of natural raw inhibitors (obtained from Fallopia japonica plant and egg white) with chlorhexidine (CHX) using an MTS viability test. Methods: Samples of GCF were collected from healthy (N = 17) individuals and (N = 65) periodontal patients. Cysteine peptidase activity was inhibited by adding a solution of cystatin from egg white (with 20% glycerol), or cystatin from knotweed, or low molecular weight inhibitors (MW < 3 kDa) from egg white and knotweed against Nα-Benzoyl-DL-arginine 4-nitroanilide hydrochloride. Results: There was a statistically significant difference between the inhibition means of cysteine protease activity for the five groups (p < 0.001). Means for the four groups of patients with periodontitis were not statistically significant different from each other (p = 0.320). The inhibition rates were higher in periodontitis patients. The toxicity of knotweed cystatin inhibitor was several times lower than the toxicity of E-64d, and of CHX. Conclusion: Cysteine protease inhibitors isolated from egg or plants were non-toxic, effectively inhibited the activity of cysteine proteases in GCF, and may be a promising alternative to more toxic standard antimicrobials (CHX) in preventing periodontal tissue breakdown. Full article

Reynoutria japonica Houtt. is the source of various phenolic compounds: phenolic acids, flawan-3-ols, and stilbenes, with a broad range of biological activity. The rhizome (underground organ of these plants) is abundant in secondary metabolites but, in natural conditions, may accumulate various toxic substances (such as heavy metals) from the soil. The principal objective of this research was to produce transformed cultures of R. japonica hairy roots that would serve as a valuable source of phenolic compounds, independent of environmental resources. The transformation was performed using a variety of wild strains of Rhizobium rhizogenes bacteria, of which only strain A4 (ATCC 31798) proved effective. The molecular characterization of transformed clones was performed using PCR. The biometric parameters (growth index and dry weight content), phenolic compounds accumulation (DAD-HPLC), antioxidant capacity (DPPH, CUPRAC), and bactericidal properties against Staphylococcus aureus with various sensitivity to antibiotics were evaluated. Two obtained transformed clones (RJ 9 and 30) exhibited the incorporation of the entire bacterial T-DNA into genomic DNA, while clones RJ 10 and 11 demonstrated only the presence of the LT-DNA sequence. The results demonstrated an increase in flawan-3-ols (catechins) accumulation in hairy root tissue relative to non-transformed (NT) plants. Moreover, hairy roots exhibited enhanced antioxidant activity and bactericidal properties compared with NT roots and NT shoots, respectively. Full article

In this article, the resveratrol content and antioxidant activity of extracts obtained from Japanese knotweed (Polygonum cuspidatum Siebold & Zucc.) were evaluated. The extracts were prepared by pressurized liquid extraction (PLE), maceration, ultrasound-assisted solvent extraction (UASE), and sea sand disruption method (SSDM) using different extractants (methanol, methanol–water mixture, and water). The following methods were used to study antioxidant properties: ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), FRAP (ferric reducing antioxidant power), DPPH (2,2′-diphenyl-1-picrylhydrazyl), and CUPRAC (cupric ion reducing antioxidant capacity). It was proven that the resveratrol content depends not only on the extraction technique used but also on the solvent and extraction temperature. High resveratrol content was obtained by maceration and PLE using a mixture of methanol and water as the extraction solvent. Among the extracts tested, these were the ones showed the greatest antioxidant properties. However, it was confirmed that not only resveratrol but also other components of the extracts are responsible for the antioxidant properties. It was therefore shown that not only resveratrol, most commonly associated with Japanese knotweed, but also other ingredients affect the biological activity of this valuable-for-health plant. Full article

Climate change is expected to affect grapevine physiology, berry quality, and yield in the Douro Demarcated Region (DDR). In this study, nettle (NE) and Japanese knotweed (JKE) extracts were tested to verify their biostimulant effect on the physiological and biochemical parameters of grapevine leaves and in vine yields. In fact, some parameters were improved after foliar application of the plant extracts, namely the photosynthetic activity and consequently, the levels of photosynthetic pigments (Clb), starch, and total soluble sugars. We also observed a reduction in lipid peroxidation, which could play a crucial role in protecting cell membranes from oxidative damage induced by the climatic conditions prevalent in this region. Therefore, we confirmed that the foliar application of plant extracts, along with the enhancement of secondary metabolites and the upregulation of plant defense genes, as previously reported, resulted in the enhancement of grapevine physiology, while also increasing the yield at harvest. In the future, these plant extracts could serve as a vital tool for winegrowers in mitigating the effects of expected changes in climatic conditions. Full article

The Russian Far East is a region of unique biodiversity, with numerous plant species, including Reynoutria japonica and Reynoutria sachalinensis. These plants are considered a serious threat to biodiversity and are classified as threatened species. However, Reynoutria plants synthesize and accumulate a variety of metabolites that are valued for their positive effects on human health. The main objective of this study is to quantitatively and qualitatively evaluate the content of secondary metabolites in different parts of R. japonica and R. sachalinensis plants. In this study, the results of phylogenetic analysis of the ITS2, matK, and rps16 genes showed that samples collected in the Sakhalin region were closest to R. sachalinensis, while samples collected in Primorsky krai were closer to R. japonica. The high-performance chromatography and mass spectrometry (HPLC-MS/MS) method was used to identify the compounds. As a result of the identification of metabolites in the leaves, stem, and roots of R. japonica and R. sachalinensis, we showed the presence of a total of 31 compounds, including stilbenes, phenolic acids, flavan-3-ols, flavones and flavonols, naphthalene derivatives, anthraquinones and derivatives, and phenylpropanoid disaccharide esters. The root of R. japonica was shown to be a rich source of stilbenes (up to 229.17 mg/g DW), which was 8.5 times higher than that of R. sachalinensis root (up to 27.04 mg/g DW). The root also contained high amounts of emodin derivatives and vanicoside B. Quercetin and its derivatives were the major metabolites in the leaves and stems of both Reynoutria species. In R. japonica leaves, quercetin-3-O-pentoside was the major compound, reaching a total of 7 mg/g DW, accounting for 34% of all compounds analyzed. In contrast, in R. sachalinensis leaves, quercitrin was the major compound (up to 13.96 mg/g DW), accounting for 62% of all compounds and 12.7 times higher than in R. japonica leaves. In turn, R. japonica leaves also contained high amounts of phenolic acids (up to 10 mg/g DW). Thus, the obtained results showed significant differences in the qualitative and quantitative composition of metabolites between R. japonica and R. sachalinensis plants. Additionally, in this work, a cell culture of R. japonica was obtained and tested for its ability to synthesize and accumulate stilbenes. Full article

We evaluated the effectiveness of three different treatment groups at managing apple shoot blight, and the resulting canker incidence and canker length on wood caused by Erwinia amylovora. Preventative foliar sprays or trunk injections of giant knotweed extract (Regalia), oxytetracycline (Arbor-OTC or FireLine + Regulaid), or streptomycin (Agri-mycin/FireWall + Regulaid) were applied to mature ‘Fuji’ trees. Regalia and oxytetracycline were ineffective at reducing shoot blight severity, showing poor disease reductions of 18.2% and 24.3% compared to untreated controls across both years. Streptomycin was effective at controlling shoot blight severity when applied as a spray application, reducing necrosis by up to 93.9% across both years. Canker incidence was also poorly reduced by Regalia and oxytetracycline with an average decrease of 33.3% and 52.4%, respectively. Again, spray applications of streptomycin were most effective at reducing canker incidence (95.2%). When present, canker length was best controlled by spray applications of streptomycin, showing an average reduction of 95.7%. The effectiveness of Regalia and oxytetracycline was poor, reducing canker length by only 30.4% and 43.5%, respectively. Trunk injections of Regalia were consistently less effective than spray applications. Compared to their spray application counterpart, Regalia injections were, on average, 12.5%, 26.3%, and 25.1% less effective at reducing shoot blight severity, canker incidence, and canker length, respectively. Injected Arbor-OTC was more effective than spray applications of oxytetracycline. On average, Arbor-OTC injections were up to 28.3%, 40.1%, and 30% more effective at reducing shoot blight severity, canker incidence, and canker length compared to spray applications. Overall, Regalia and oxytetracycline were not as effective as streptomycin at controlling fire blight. The search for organic antibiotic alternatives for shoot blight and canker control continues, as cankers are increasing in economic importance by causing bearing wood and young tree death. Full article

Polygonum cuspidatum, alternatively known as Fallopia japonica or Reynoutria japonica, is a perennial herb belonging to the Polygonaceae family. Commonly called Japanese knotweed or Asian knotweed, this plant is native to East Asia, particularly in regions such as Korea, China, and Japan. It has successfully adapted to a wide range of habitats, resulting in it being listed as a pest and invasive species in several countries in North America and Europe. This study focuses on analysing the composition of the bacterial and fungal endophytic communities associated with Japanese knotweed growing in the Russian Far East, employing next-generation sequencing (NGS) and a cultivation-based method (microbiological sowing). The NGS analysis showed that the dominant classes of endophytic bacteria were Alphaproteobacteria (28%) and Gammaproteobacteria (28%), Actinobacteria (20%), Bacteroidia (15%), and Bacilli (4%), and fungal classes were Agaricomycetes (40%), Dothideomycetes (24%), Leotiomycetes (10%), Tremellomycetes (9%), Pezizomycetes (5%), Sordariomycetes (3%), and Exobasidiomycetes (3%). The most common genera of endophytic bacteria were Burkholderia-Caballeronia-Parabukholderia, Sphingomonas, Hydrotalea, Methylobacterium-Metylorubrum, Cutibacterium, and Comamonadaceae, and genera of fungal endophytes were Marasmius, Tuber, Microcyclosporella, Schizothyrium, Alternaria, Parastagonospora, Vishniacozyma, and Cladosporium. The present data showed that the roots, leaves, and stems of P. cuspidatum have a greater number and diversity of endophytic bacteria and fungi compared to the flowers and seeds. Thus, the biodiversity of endophytic bacteria and fungi of P. cuspidatum was described and analysed for the first time in this study. Full article

Sea buckthorn and Japanese knotweed are known in many traditional medicine systems to be a great source of bioactive substances. This research aims to compare the bioactivity and protective effects of the phenolic extracts of leaves from sea buckthorn and roots and leaves from the Japanese knotweed on erythrocytes. The polyphenol composition of the extract was analyzed using UPLC-PDA-ESI-MS/MS. The extracts’ toxicity and impact on the erythrocytes’ osmotic fragility were measured spectrophotometrically. The antioxidant activity was determined based on the inhibition of oxidation of erythrocytes and their membrane induced by 2,2′-Azobis(2-methylpropionamidine) dihydrochloride (AAPH),measured spectrophotometrically and using fluorimetry. To find the possible mechanism of the extracts’ action, extract-modified cells were observed under a microscope, and the potential localization of the extract’s phytochemical composition was checked using fluorescent probes. The results showed that the used extracts are not toxic to erythrocytes, increase their osmotic resistance, and successfully protect them against free radicals. Extract components localize on the outer part of the membrane, where they can scavenge the free radicals from the environment. Altogether, the presented extracts can greatly protect living organisms against free radicals and can be used to support the treatment of diseases caused by excess free radicals. Full article

Invasive knotweeds are rhizomatous and herbaceous perennial plants that pose significant ecological threats due to their aggressive growth and ability to outcompete native plants. Although detecting and identifying knotweeds is crucial for effective management, current ground-based survey methods are labor-intensive and limited to cover large and hard-to-access areas. This study was conducted to determine the optimum flight height of drones for aerial detection of knotweeds at different phenological stages and to develop automated detection of knotweeds on aerial images using the state-of-the-art Swin Transformer. The results of this study found that, at the vegetative stage, Japanese knotweed and giant knotweed were detectable at ≤35 m and ≤25 m, respectively, above the canopy using an RGB sensor. The flowers of the knotweeds were detectable at ≤20 m. Thermal and multispectral sensors were not able to detect any knotweed species. Swin Transformer achieved higher precision, recall, and accuracy in knotweed detection on aerial images acquired with drones and RGB sensors than conventional convolutional neural networks (CNNs). This study demonstrated the use of drones, sensors, and deep learning in revolutionizing invasive knotweed detection. Full article

Fallopia japonica (FJ), commonly known as Japanese knotweed, is now recognized as one of the most invasive plants in Europe and globally. Despite its widespread presence in Europe and its significant nectar production, there is currently limited scientific data on the unique unifloral honey derived from it. This study examines the physicochemical composition of Fallopia japonica honey (FJH) samples collected from various regions in Romania. Additionally, the nutritional and antioxidant profiles of FJH were assessed. The sensory analysis revealed a honey with a brown-caramel color and an intense flavor, characterized by fine, consistent crystals during crystallization. The results indicated that FJH has a high carbohydrate content (fructose: 35.12–40.65 g/100 g; glucose: 28.06–37.79 g/100 g); elevated electrical conductivity (387–692 µS/cm), diastase activity (9.11–17.01 DN), and acidity (21.61–42.89 meq/kg); and substantial total phenolic (89.87–120.08 mg/100 g) and flavonoid (18.13–39.38 mg/g) contents. These findings highlight FJH’s favorable nutritional properties, aligning with the standard codex for honey. The antioxidant profile of FJH demonstrated strong DPPH and ferric reduction antioxidant power (FRAP) activities, comparable to those of buckwheat honey, underscoring its potential health benefits and commercial value. These results provide new insights into how this invasive plant can be harnessed as a valuable resource for sustainable beekeeping practices. Full article

Although N,N-diethyl-3-methylbenzamide (DEET) remains the most effective repellent against mosquitoes and ticks, concerns about skin irritation, rashes, and neurological problems in children have driven the search for natural alternatives. The aim of this research was to develop, manufacture, and test prototype stickers derived from invasive plant species in Europe. These labels contained a coating with encapsulated repellents made from essential oils to protect against mosquito bites and similar blood-sucking insects. Six samples of invasive plant species in Europe such as Japanese knotweed (Fallopia japonica), goldenrod (Solidago gigantea), and black locust (Robinia pseudoacacia) were coated with two essential oil mixtures (of geranium, lavender, and eucalyptus) and were encapsulated on solid carriers for prolonged evaporation. Analysis of the structural properties (weight, thickness, density, and specific volume) were carried out on the coated label samples. Analysis of surface properties (roughness and porosity), capillary absorption, and a comparison of time and evaporation of essential oils were also carried out. Scanning electron microscopy was performed on the samples and the solid carrier with different mixtures of essential oils. The Japanese knotweed sample, coated with a blend of geranium, lavender, and eucalyptus essential oils, showed the highest efficacy and stability. Full article

Invasive alien plant species (IAPS) may cause threats to native biodiversity in ecosystems. Researchers have been investigating all the possible ways that they can be used effectively for other purposes. Since IAPS are capable of forming cellulose fibre nets, in this research, papers were made from three different types of IAPS (Japanese knotweed, giant goldenrod, and black locust). This research examined these IAPS papers and their effectiveness when used as printing substrates. In comparison to commercial office paper, the differences in basic, surface, optical, and microscopic properties were measured. As a widely used technology, inkjet printing was applied. We tested a commonly used sans-serif typeface (which has been established as being more legible than other typefaces in previous research) in three different type sizes (i.e., 8, 10, and 12 pt). According to the results, paper made from IAPS could offer some usable properties and acceptable legibility, especially when printing typefaces with specific attributes, such as moderate counter size, higher x-height, and minimal differences in the letter stroke width, are used. An appropriate typographic tonal density should be achieved in combination with an adequate letter size, e.g., 10 pt type size when a sans-serif typeface is used. Full article

Fallopia japonica (Japanese knotweed, Reynoutria japonica or Polygonum cuspidatum) is considered an extremely invasive plant worldwide and a bioindicator of heavy metals. Yet, its potential as a crop for honeybees is still underevaluated. This study employs atomic absorption spectrometry to quantitatively analyze the concentration of macro-elements, namely, calcium (Ca), potassium (K) and magnesium (Mg); micro-elements, such as copper (Cu), iron (Fe), manganese (Mn) and selenium (Se); and trace elements, i.e., cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb) in different anatomic parts of Fallopia japonica (FJ) plants (roots, rhizomes, stems, leaves) and their traceability into honey. This research encompasses a thorough examination of samples collected from the northwestern and western part of Romania, providing insights into their elemental composition. The results showed that the level of trace elements decreases in terms of traceability in honey samples (Pb was not detected in any of the analyzed samples, while Cd had a minimum content 0.001 mg/kg), ensuring its quality and health safety for consumption. Moreover, the data generated can function as a valuable resource to explore the plant’s positive eco-friendly impacts, particularly in relation to its honey. Full article

Japanese knotweed (Reynoutria japonica Houtt.) is Poland’s invasive weed, for which there is no efficient control method. The rhizomes of this species are rich in resveratrol. In this work, we evaluated (1) the effectiveness of electromagnetic microwaves (MV) in destroying Japanese knotweed using an original device, HOGWEED (MV of 2450 MHz), (2) the ecotoxic effect of the MV on the soil environment, and (3) the resveratrol content in knotweed rhizomes after MV treatment. The field studies were carried out in 2022 in southern Poland. Cut plants were MV-treated for times of 5.0–25.0 min. The MV efficiency was checked 10 and 56 days after treatment (DAT). After MV treatment, fresh soil samples were taken to analyze their ecotoxicity. As a result, at 56 DAT, knotweed was controlled if MV was used for at least 20.0 min. The MV did not affect the soil ecotoxicity. The MV-treated soils were classified as non-toxic or low-toxic. To analyze the resveratrol content, healthy knotweed rhizomes were dug out, treated with MV in the laboratory at 2.5–10.0 min, and analyzed for resveratrol content in HPLC-MS/MS. As a result, the resveratrol in the rhizomes significantly decreased in a time-dependent manner following MV exposure. Full article