ABSTRACT
Three cyst-forming Sarcocystis species have been identified in horsemeat; however, there exists considerable confusion concerning their relationships. Here, 74% (34/46) of the examined tissue samples from horses contained sarcocysts based on examination by light microscopy (LM), and the organism was identified as Sarcocystis bertrami based on cyst structure. The S. bertrami cysts were microscopic (up to 6750 µm in length) and exhibited a striated wall with 2.0-5.1 µm villar protrusions (vps) under LM. Transmission electron microscopy (TEM) observations showed that the vps were tightly packed, similar to "type 11c". Four genetic markers (18S, 28S, ITS1 and the mitochondrial cox1 gene) of S. bertrami were sequenced and analyzed. The 28S and ITS1 sequences are the first records for Sarcocystis in horses. The newly obtained sequences of the 18S and cox1 genes both shared the highest similarities with those of S. bertrami and S. fayeri obtained from horses. Phylogenetic analysis based on the 18S, 28S and cox1 sequences revealed that S. bertrami and S. fayeri formed an independent clade within a group comprising Sarcocystis spp. from ruminants and pigs. Therefore, S. bertrami and S. fayeri are considered to represent the same species of Sarcocystis in horses, and S. fayeri is a junior synonym of Sarcocystis bertrami.
TITLE: Prévalence et caractéristiques morphologiques et moléculaires de Sarcocystis bertrami chez les chevaux en Chine. ABSTRACT: Trois espèces de Sarcocystis formant des kystes ont été identifiées dans la viande de cheval, mais il existe une confusion considérable concernant leurs relations. Ici, 74 % (34/46) des échantillons de tissus examinés provenant de chevaux contenaient des sarcocystes selon l'examen par microscopie optique (LM), et l'organisme a été identifié comme Sarcocystis bertrami selon la structure du kyste. Les kystes de S. bertrami étaient microscopiques (jusqu'à 6 750 µm de longueur) et présentaient une paroi striée avec des saillies villaires (vp) de 2,0 à 5,1 µm sous LM. Les observations en microscopie électronique à transmission ont montré que les vp étaient très serrées, similaires au « type 11c ¼. Quatre marqueurs génétiques (18S, 28S, ITS1 et le gène mitochondrial cox1) de S. bertrami ont été séquencés et analysés. Les séquences de 28S et ITS1 sont les premières de Sarcocystis chez les chevaux. Les séquences nouvellement obtenues de 18S et des gènes mitochondriaux cox1 partagent les similitudes les plus élevées avec celles de S. bertrami et S. fayeri obtenues à partir de chevaux. Une analyse phylogénétique basée sur les séquences de 18S, 28S et cox1 a révélé que S. bertrami et S. fayeri formaient un clade indépendant au sein d'un groupe comprenant les Sarcocystis spp. des ruminants et des porcs. Par conséquent, S. bertrami et S. fayeri sont considérés comme représentant la même espèce de Sarcocystis chez les chevaux, et S. fayeri est un synonyme plus récent de Sarcocystis bertrami.
Subject(s)
Horse Diseases/epidemiology , Sarcocystis/genetics , Sarcocystosis/veterinary , Animals , China/epidemiology , DNA, Ribosomal/genetics , Genes, Mitochondrial , Genetic Variation , Horse Diseases/parasitology , Horses/parasitology , Phylogeny , Prevalence , RNA, Ribosomal, 18S/genetics , Sarcocystis/classification , Sarcocystosis/epidemiologyABSTRACT
The present study was designed to investigate the bioactive constituents of Xanthoceras sorbifolia in terms of amounts and their antioxidant, DNA scission protection, and α-glucosidase inhibitory activities. Simultaneous quantification of 10 X. sorbifolia constituents was carried out by a newly established ultra-high performance liquid chromatography-quadrupole mass spectrometry method (UHPLC-MS). The antioxidant activities were evaluated by measuring DPPH radical scavenging and DNA scission protective activities. The α-glucosidase inhibitory activities were investigated by using an assay with α-glucosidase from Bacillus Stearothermophilus and disaccharidases from mouse intestine. We found that the wood of X. sorbifolia was rich in phenolic compounds with the contents of catechin, epicatechin, myricetin, and dihydromyricetin being 0.12-0.19, 1.94-2.16, 0.77-0.91, and 6.76-7.89 mg·g(-1), respectively. The four constituents strongly scavenged DPPH radicals (with EC50 being 4.2, 3.8 and 5.7 µg·mL(-1), respectively) and remarkably protected peroxyl radical-induced DNA strand scission (92.10%, 94.66%, 75.44% and 89.95% of protection, respectively, at a concentration of 10 µmol·L(-1)). A dimeric flavan 3-ol, epigallocatechin-(4ßâ8, 2ßâO-7)-epicatechin potently inhibited α-glucosidase with an IC50 value being as low as 1.2 µg·mL(-1). The established UHPLC-MS method could serve as a quality control tool for X. sorbifolia. In conclusion, the high contents of antioxidant and α-glucosidase inhibitory constituents in X. sorbifolia support its use as complementation of other therapeutic agents for metabolic disorders, such as diabetes and hypertension.