The activity of polyphenolic compounds, triterpenoids, carotenoids, chlorophylls and antioxidants in leaves and rhizomes of
Fallopia japonica
Houtt and
Fallopia sachalinensis
(F.Schmidt) grown in ...Poland was investigated. Leaves and rhizomes were assessed for the presence of bioactive compounds with the ultra-performance liquid chromatography photodiode detector-quadrupole/time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS) method, and for antioxidant activity with the on-line UPLC-ABTS screening. Forty-six polyphenolic compounds (15 phenolic acids, 12 flavones and flavonols, 11 flavan-3-ols and 8 stilbenes), were identified in
Fallopia japonica and Fallopia sachalinensis
. Furthermore, accurate mass measurement technique was for the first time in
Fallopia japonica
Houtt and
Fallopia sachalinensis
(F.Schmidt) in leaves and rhizomes it identified 25 new compounds belonging to carotenoids (9), chlorophylls (13) and triterpenoids (3) as well as rated the antioxidant properties of each polyphenolic compound. Major qualitative differences were found in the profiles. The leaves and rhizomes were found to be a good source not only of (average 20408.18 and 2716.42 mg/100 g dm), but also chlorophylls (average 179.97 and 43.82 mg/100 g dm), carotenoids (average 100.23 and 53.25 mg/100 g dm) and triterpenoids (average 580.87 and 434.05 mg/100 g dm). The content of bioactive compounds in
Fallopia japonica
Houtt was around 8.0, 4.0, 2.0 and 1.3 times higher than the content of polyphenols, chlorophylls, carotenoids and triterpenoids in
Fallopia sachalinensis
(F.Schmidt). The accurate identification of
Fallopia
bioactive compounds is an indispensable detailed knowledge of the profile and step toward better understanding of the medicinal properties of the species and also potentially more extensive use of the plant.
Japanese knotweed (Fallopia japonica Houtt.) and Bohemian knotweed (Fallopia x bohemica) are invasive alien plant species, causing great global ecological and economic damage. Mechanical excavation ...of plant material represents an effective containment method, but it is not economically and environmentally sustainable as it produces an excessive amount of waste. Thus, practical uses of these plants are actively being sought. In this study, we explored the carotenoid profiles and carotenoid content of mature (green) and senescing leaves of both knotweeds. Both plants showed similar pigment profiles. By means of high performance thin-layer chromatography with densitometry and high performance liquid chromatography coupled to photodiode array and mass spectrometric detector, 11 carotenoids (and their derivatives) and 4 chlorophylls were identified in green leaves, whereas 16 distinct carotenoids (free carotenoids and xanthophyll esters) were found in senescing leaves. Total carotenoid content in green leaves of Japanese knotweed and Bohemian knotweed (378 and 260 mg of lutein equivalent (LE)/100 g dry weight (DW), respectively) was comparable to that of spinach (384 mg LE/100 g DW), a well-known rich source of carotenoids. A much lower total carotenoid content was found for senescing leaves of Japanese and Bohemian knotweed (67 and 70 mg LE/100 g DW, respectively). Thus, green leaves of both studied knotweeds represent a rich and sustainable natural source of bioactive carotenoids. Exploitation of these invaders for the production of high value-added products should consequently promote their mechanical control.
Fallopia japonica (Japanese knotweed) is an aggressively invasive herbaceous perennial that causes substantial economic and environmental damage in the United Kingdom (UK). As such, it is of ...considerable concern to councils, environmental groups, private landowners and property developers. We construct a 3D correlated random walk model of the development of the subterranean rhizome network for a single stand of
F. japonica. The formulation of this model uses detailed knowledge of the morphology and physiology of the plant, both of which differ in the UK to that of its native habitat due to factors including a lack of predation and competition, longer growth seasons and favourable environmental conditions in the UK. Field data obtained as a part of this study are discussed and used in the model for parameterisation and validation. The simulation captures the field data well and predicts, for example, quadratic growth in time for the stand area. Furthermore, the role of a selection of parameters on long-term stand development are discussed, highlighting some key factors affecting vegetative spread rates.
Sexual reproduction is known to be an important means of propagation for native Japanese knotweed populations in Asia. For naturalized populations in the United States, however, its relative ...importance compared with propagation by rhizome and stem fragments has not been established. This article presents two related studies that address two basic questions regarding the potential for propagation by seed: (1) are seeds that are produced by Japanese knotweed in areas of Philadelphia, PA, capable of germinating in the field? If so, (2) when and how rapidly during the year do these seeds acquire germinability? Field germination experiments assessed germination of planted seeds at intervals during the growing season at two different study sites (one in 2000 and the other in 2002) and showed that germination was common at both sites. The 2002 experiment also demonstrated that germination occurred both within existing stands of Japanese knotweed and in areas well removed from existing stands, and that both planted and naturally occurring seeds germinated. Experiments on seasonal acquisition of seed germinability used batches of seeds collected weekly between early September and November 2000 from three different study sites. Results showed that at two of the study sites, a rapid increase in germinability from less than 10% to greater than 90% occurred between collection dates in mid-September and mid-October 2000. A smaller and more gradual change occurred at the third site, where maximum germinability was roughly 50%. Regarding management of Japanese knotweed, the field germination experiments suggest that spread of this plant by seed is a realistic possibility in the United States. Because of the rapidity with which germinability is acquired, the high germinability attained, and the large number of seeds produced, we recommend that female (male-sterile) plants or their inflorescences be removed from seed-producing populations before the formation of fruits to minimize spread by seed.
Japanese knotweed, Fallopia japonica (Houtt.) Ronse Decr. comes from submeriodional and oceanic areas of Eastern Asia. The material for our research was sampled from a Japanese knotweed stand ...situated on a SW oriented slope by a main road, under a line of family houses in construction. The part of the stand adjacent to the road was regularly mown by the Technical Services of the Banská Štiavnica town. The stand was 5 x 3 m in size. The experiment was running over two growing seasons: 2002 and 2003. The study material consisted of 30 rhizome segments with three different lengths (2 cm, 5 cm, 8 cm). The plants had been regenerated in the following proportions: 90% exemplars of 8 cm segments, 63% of 5 cm segments and 60% of 2 cm resulted in new plants towards the end of experiment No 1. Experiment No. 2 gave rather different results: by 70% regenerated exemplars in case of 8 cm and 2 cm segments, 67% in case of 5 cm segments. The reasons of these differences are explained in the discussion. The growth dynamics and final size of the regenerated plants were dependent on the segment length.
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