No abstract

Shells are by-products of oil production from Camellia oleifera which have not been harnessed effectively. The purpose of this research is to isolate flavonoid from shells of Camellia oleifera and evaluate its anti-inflammatory and analgesic effects. The flavonoid was identified as bimolecular kaempferol structure by UV, MS, 1H NMR and 13C NMR spectra, which is a new biflavonoid and first found in Camellia oleifera. It showed dose-dependent anti-inflammatory activity by carrageenin-induced paw oedema in rats and croton oil induced ear inflammation in mice, and analgesic activity by hot plate test and acetic acid induced writhing. The mechanism of anti-inflammation of biflavonoid is related to both bradykinin and prostaglandins synthesis inhibition. The biflavonoid showed both central and peripheral analgesic effects different from aspirin, inhibition of the synthesis or action of prostaglandins may contribute to analgesic effect of biflavonoid. The biflavonoid significantly decreased malonaldehyde (MDA) and increased superoxidase dismutase (SOD) and Glutathione peroxidase (GSH-Px) activity in serum (p < 0.01), revealed strong free radical scavenging activity in vivo. It indicates the biflavonoid can control inflammation and pain by eliminating free radical so as to inhibit the mediators and decrease the prostaglandins. The biflavonoid can be used as a prospective medicine for inflammation and pain.

In this paper, a prey-predator model and weak Allee effect in prey growth and its dynamical behaviors are studied in detail. The existence, boundedness, and stability of the equilibria of the model are qualitatively discussed. Bifurcation analysis is also taken into account. After incorporating the searching delay and digestion delay, we establish a delayed predator-prey system with Allee effect. The results show that there exist stability switches and Hopf bifurcation occurs while the delay crosses a set of critical values. Finally, we present some numerical simulations to illustrate our theoretical analysis.

No abstract

In this paper, we establish a reaction-diffusion predator-prey model with weak Allee effect and delay and analyze the conditions of Turing instability. The effects of Allee effect and delay on pattern formation are discussed by numerical simulation. The results show that pattern formations change with the addition of weak Allee effect and delay. More specifically, as Allee effect constant and delay increases, coexistence of spotted and stripe patterns, stripe patterns, and mixture patterns emerge successively. From an ecological point of view, we find that Allee effect and delay play an important role in spatial invasion of populations.