scholarly journals Growth suppression survey of Japanese knotweed (Reynoutria sachalinensis (Fr. Schm.) Nakai) in the mesh sheet covering area

2021 ◽  
Vol 47 (1) ◽  
pp. 169-170
Author(s):  
Atsuko SATO ◽  
Hirochika HAYASHI
Antioxidants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 133
Author(s):  
Urška Jug ◽  
Katerina Naumoska ◽  
Irena Vovk

The antioxidant activities of Japanese knotweed rhizome bark extracts, prepared with eight different solvents or solvent mixtures (water, methanol, 80% methanol(aq), acetone, 70% acetone(aq), ethanol, 70% ethanol(aq), and 90% ethyl acetate(aq)), were determined using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging assay. Low half maximal inhibitory concentration (IC50) values (2.632–3.720 µg mL−1) for all the extracts were in the range of the IC50 value of the known antioxidant ascorbic acid at t0 (3.115 µg mL−1). Due to the highest extraction yield (~44%), 70% ethanol(aq) was selected for the preparation of the extract for further investigations. The IC50 value calculated for its antioxidant activity remained stable for at least 14 days, while the IC50 of ascorbic acid increased over time. The stability study showed that the container material was of great importance for the light-protected storage of the ascorbic acid(aq) solution in a refrigerator. Size exclusion–high-performance liquid chromatography (SEC-HPLC)–UV and reversed phase (RP)-HPLC-UV coupled with multistage mass spectrometry (MSn) were developed for fractionation of the 70% ethanol(aq) extract and for further compound identification, respectively. In the most potent antioxidant SEC fraction, determined using an on-line post-column SEC-HPLC-DPPH assay, epicatechin, resveratrol malonyl hexoside, and its in-source fragments (resveratrol and resveratrol acetyl hexoside) were tentatively identified by RP-HPLC-MSn. Moreover, epicatechin was additionally confirmed by two orthogonal methods, SEC-HPLC-UV and high-performance thin-layer chromatography (HPTLC) coupled with densitometry. Finally, the latter technique enabled the identification of (−)-epicatechin. (−)-Epicatechin demonstrated potent and stable time-dependent antioxidant activity (IC50 value ~1.5 µg mL−1) for at least 14 days.


Cellulose ◽  
2021 ◽  
Author(s):  
Nina Čuk ◽  
Martin Šala ◽  
Marija Gorjanc

Abstract The development of cellulose-based textiles that are functionalised with silver nanoparticles (AgNP), synthesised according to a green approach, and offer protection against ultraviolet (UV) radiation and pathogenic bacteria is very important today. In the present work we demonstrate the environmentally friendly approach to obtain such textile material by AgNP synthesis directly (in-situ) on cotton fabrics, using water extracts of plant food waste (green tea leaves, avocado seed and pomegranate peel) and alien invasive plants (Japanese knotweed rhizome, goldenrod flowers and staghorn sumac fruit) as reducing agents. The extracts were analysed for their total content of phenols and flavonoids and their antioxidant activity. The synthesised AgNP on cotton were round, of different size and amount depending on the reducing agent used. The highest amount of AgNP was found for samples where Japanese knotweed rhizome extract was used as reducing agent and the lowest where extracts of goldenrod flowers and green tea leaves were used. Regardless of the reducing agent used to form AgNP, all cotton samples showed excellent protection against E. coli and S. aureus bacteria and against UV radiation with UV protection factor values above 50. The best results for UV protection even after the twelve repetitive washing cycles were found for the sample functionalized with AgNP synthesised with an extract of the Japanese knotweed rhizome. Due to the presence of AgNP on cotton, the air permeability and thermal conductivity decreased. AgNP had no effect on the change in breaking strength or elongation of fabrics. Graphic abstract


Rhizosphere ◽  
2021 ◽  
Vol 18 ◽  
pp. 100340
Author(s):  
Claudio A. Lagos ◽  
Tsiri Díaz ◽  
Estefania Saucedo ◽  
Cesar Arriagada ◽  
John Larsen ◽  
...  

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1232
Author(s):  
Rozalija Cvejić ◽  
Susanne Klages ◽  
Marina Pintar ◽  
Lara Resman ◽  
Ana Slatnar ◽  
...  

In this study, fermentation-based organic fertilizer (OF) was produced from the aboveground parts of Fallopia japonica (Houtt.) Ronse Decr. The quantity of N in OF (17.2 kg t−1 fresh lactic-fermented OF) was higher than average in cattle farmyard manure, but on a comparable level to solid poultry and rabbit manure. The OF was applied on a field to evaluate its effect on Chinese cabbage. The applied nutrients with OF N159 were 159, 44 and 121 kg ha−1 for N, P, and K, respectively. The applied nutrients with OF N317 were 317, 38, and 200 kg ha−1 for N, P, and K, respectively. The average mass of marketable Chinese cabbage (Brassica pekinensis Rupr.) single heads ranged from 253 g with N0 treatment to 602 g with N317 treatment. The nutrient recovery efficiency REN,P,K was 37, 20, and 50% for N317 and 55, 48, and 77% for N159. The OF was found to be a suitable alternative to farmyard manure. Additionally, OF produced from F. japonica could complement existing approaches to limit the spread of invasive species in cities. Further research should focus on perennial crop rotations and cropping patterns, different soil types, and a greater variety of crops and consider the possible retention of urban farmers using fertilizer from invasive plants.


2021 ◽  
pp. 116776
Author(s):  
Mark T.J. Barwood ◽  
Peter J. Metaxas ◽  
Vincent W.S. Lim ◽  
Michael L. Johns ◽  
Zachary M. Aman ◽  
...  

1998 ◽  
Vol 184 (2) ◽  
pp. 105-111 ◽  
Author(s):  
Stanislava Stošić-Grujičić ◽  
Vladimir Trajković ◽  
Vladimir Badovinac ◽  
Marija Mostarica Stojković

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