2018) Enhanced catalytic reduction of paranitrophenol using α-MoO 3 molybdenum oxide nanorods and stacked nanoplates as catalysts prepared from different precursors, Journal of Taibah University for Science, 12:2, 133-137, ABSTRACT Molybdenum oxide, α-MoO 3 , nanorods and stacked nanoplates were prepared from oxalate, citrate and tartrate precursors. These molybdenum oxides showed high efficiencies in the reduction of para-nitrophenol to para-aminophenol in the presence of NaBH 4 . The prepared precursors were first characterized by thermal gravimetric analysis (TGA) and then thermally decomposed at 350°C (oxalate precursor) and 550°C (citrate and tartrate precursors). The final oxides were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and the Braunauer-Emmet-Teller (BET) technique. The oxalate precursor is the most efficient catalyst for the reduction reaction. ARTICLE HISTORY
Four previously unrecognized trypanorhynchids are described based on fish specimens from Sparidae and Mullidae host fish of the Red Sea. From September 2010 to June 2011, 66 specimens of the sea bream Pagrus pagrus (F: Sparidae) and 43 of the red mullet Mullus barbatus (F: Mullidae) were purchased from markets in the Suez and Hurghada cities of the Red Sea. The fishes were measured, and their organs investigated for helminth infections. Forty-one (37.6 %) out of the 109 fish specimens investigated were parasitized with Trypanorhyncha metacestodes, identified as Callitetrarhynchus speciouses Linton 1897, Pseudogrillotia sp. Dollfus 1969, Kotorella pronosoma Stossich 1901 from P. pagrus, and Nybelinia bisulcata Linton 1889 from M. barbatus in the mesentery and peritoneal cavity, with prevalences of 16.5, 11.0, 6.0, and 12.0 %. All of these larval stages were encapsulated larvae in blastocysts. C. speciouses is characterized by an elongated scolex, two bothria, a long postbulbosa, and four elongated bulbs. Pseudogrillotia sp. possesses a scolex with two lateral patelliform bothridia; posterior margins are free, not notched. A long sheath was observed, which was irregularly coiled when tentacles invaginated. N. bisulcata possesses an acraspedote scolex with four bothridia, which are broad, bean-shaped. The tentacles are spirally coiled, supplied with hooks with abruptly turned points. The four tentacles sheaths rose from scolex as two anterior (front) and two posterior (back) which overlap at the apices of bulbs. K. pronosoma is characterized by a short body with a craspedote scolex and four bothridia. The tentacles are short and emerge pairwise. The presence of Trypanorhyncha metacestodes in the muscles does not represent a risk of infection for humans. They have a negative effect on fish esthetics. The repugnant aspect and the prohibition for commercial use by sanitary inspectors, however, cause consumer rejection. Parasites of the order Trypanorhyncha have been recorded in these host fishes for the first time.
Saudi Arabia has a developing aquaculture industry that farms primarily tilapia. Although trichodinids are presumably the most usually encountered protozoan parasites in these cultured fish, they have rarely been studied in this context, and there is no data on the species that might infect cultured tilapia in Saudi Arabia. The present study was therefore carried out as a general survey to investigate the occurrence and identify the species of trichodinids that can infect cultured tilapia (Oreochromis niloticus) in Saudi Arabia. A total of 500 tilapia fish were collected from fish farms in Riyadh city and examined in order to determine the species of trichodinids present in the positive specimens. Three species of trichodinids (Trichodina maritinkae, T. centrostrigeata and T. frenata) were isolated and described as new records in Saudi Arabia. These trichodinids were found simultaneously in the same fish with overall prevalence of 20% (100/500). The identification and characterization of these three species are documented based on Riyadh specimens, for the first time. Additionally, the present paper confirms the existence of T. frenata for the second time globally and establishes this trichodinid as a new parasite for O. niloticus. T. maritinkae is highly specific to clariids, and previously, it has not been reported from any fish species other than clariids. The present work also confirmed that T. centrostrigeata can also infest cichlid fish. The list of host records of these species is expanded and their host specificity re-evaluated based on the results of this study in addition to the previously published data. We conclude that there is a need for further study of the impacts of these Trichodina spp. on Saudi Arabian fishery sector.
Developmental stages of Hepatozoon seurati (Laveran and Pettit 1911) comb. nov. are described from the tissues of the corned viper Cerastes cerastes, and from the vector Culex pipiens. The parasite described in the present study is firstly recorded as Haemogregarina seurati (Laveran and Pettit 1911) in the same host. After demonstration of the sporogonous development in the mosquito vector (C. pipiens) which showed all characteristics of the genus Hepatozoon (large oocysts containing many sporocysts producing numerous sporozoites), the parasite should be transferred into the genus Hepatozoon. The infected erythrocytes measured 20 ± 0.95 × 7.3 ± 0.85 μm; while uninfected cells measured 13.3 ± 1.04 × 7.5 ± 0.16 μm. Hypertrophy and faintly stained cytoplasm are mostly occurred in infected erythrocytes. Blood stages of the parasite were found exclusively in the erythrocytes in two forms: (1) small trophozoites (10.0 ± 0.52 × 3.0 ± 0.4 μm) and (2) long (mature) sausage-shaped (16.5 ± 1.5 × 3.5 ± 0.4 μm). Merogony occurred in the endothelial cells of the blood capillaries of lung, liver, and spleen. Mature meronts was 27.6 ± 0.7 × 17.5 ± 0.5 μm in diameter and contained 20-35 merozoites (averaged in 26). These merozoites measured 16.5 ± 1.5 × 3.5 ± 0.4 μm. Syzygy and gamogony occurred in the mosquito myxocoel till the 5th day post-infection (p.i.) while sporogony took place after 15 days p.i. On the third day p.i., a large spherical macrogamete of 29.0 ± 0.8 × 20.5 ± 0.6 μm containing a distinct nucleus in association with a single microgamete were observed. The microgamete was pyriform measured 8 ± 02 μm in length. It had a prominent nucleus and a long flagellum of at least 20.4 ± 1.3 μm in length. Fertilization occurred on the 3rd to the 4th days p.i. and the formed zygote developed into an oocyst in which repeated mitotic divisions with centripetal invaginations occurred producing sporoblasts. After sporulation, each sporoblast termed as sporocyst, and contained 18 banana-shaped sporozoites measured 14.0 ± 1.6 × 3.2 ± 0.6 μm. Experimental transmission was successful by intraperitoneal inoculation of the infective stages (sporozoites) to uninfected vipers and led to the appearance of blood stages after 5-6 weeks.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.