ABSTRACT
Abstract Betta rubra is an ornamental freshwater fish endemic to northern Sumatra, Indonesia. The B. rubra population has decreased in recent decades, and is classified as an endangered species in the IUCN Red List. This study aims to report for the first time infection by L. cyprinacea in B. rubra harvested from the Aceh Besar region of Indonesia. The fish samples were obtained from the Cot Bira tributaries, Aceh Besar District, Indonesia from January to December 2020. The results showed that the parasite infected 6 out of 499 samples in August and September, with a prevalence and intensity rate of 1% and 2 parasites/fish, respectively. The eyes and pectoral fins were the common infection sites. Despite B. rubra is not an optimal host (small size) for the parasite, this parasite might serve as additional threatening factors for the endangered B. rubra fish population.
Resumo Betta rubra é um peixe de água doce ornamental endemico da região norte Sumatra, Indonesia. A população de Betta rubra diminuiu ao longo dos anos, sendo classificada como espécie em extinção na Lista Vermelha da IUCN. Este estudo tem como objetivo relatar pela primeira vez infecção por L. cyprinacea em B. rubra coletados na região de Aceh Besar na Indonésia. As amostras de peixes foram obtidas nos afluentes Cot Bira, distrito de Aceh Besar, Indonésia de janeiro a dezembro de 2020. Os resultados mostraram que o parasito infectou 6 das 499 amostras em agosto e setembro, com uma prevalência e taxa de intensidade de 1% e 2 parasitas/peixes, respectivamente. Os olhos e as nadadeiras peitorais foram os sítios de infecção mais comuns. Apesar de B. rubra não ser um hospedeiro ideal (pequeno tamanho) para o parasita, este parasita pode servir como fator de ameaça adicional para a população de peixes B. rubra, ameaçada de extinção.
Subject(s)
Animals , Copepoda , Acetone/analogs & derivatives , Fishes/parasitology , Fresh Water , Hydrazones , Indonesia/epidemiologyABSTRACT
Textile Industries use different chemicals in indigo dyeing processes. Interest in eco-friendly processing in the textile industry has recently increased because of a larger awareness of environmental issues. For the case of indigo dyeing process, the reducing agent conventionally used is the - environmentally unfavourable - sodium dithionite, which will be replaced in this study with an ecological reducing agent called acetol that is also known as hydroxyacetone. In this paper, measurements of the redox potential at various experimental conditions were carried out in a dyeing bath, where acetol is the reducing agent of indigo. Moreover, an unconventional but eco-friendly indigo dyeing process of cotton was investigated. The effects of: reduction duration, dyeing duration, reduction temperature, alkalinity and the amount of indigo on the performances of this dyeing process were studied, and the dyeing results were evaluated by measuring the colour yield parameter [K/S] of the dyed samples at 660 nm. Finally, a factorial design was employed for the experimental plan; mathematical model equation and statistical analysis were derived by computer simulation applying the least squares method using Minitab 15
Subject(s)
Coloring Agents , Textile Industry , Acetone/analogs & derivatives , Reducing AgentsABSTRACT
Application of juvenile hormone esterase inhibitor 3-octylthio-1,1,1- trifluropropan-2-one (OTFP) to 5th instar nymphs and virgin females of D. cingulatus revealed the profound role played by juvenile hormone esterase (JHE) in metamorphosis and reproduction. The ability of OTFP to cause delay and the formation of malformed nymphs, suggests that inhibition of JHE in vivo maintains a higher than normal hemolymph JH titer. It is obvious that OTFP does inhibit in vivo JHE activity in late instar nymphs. Further, the application of JHE inhibitor, OTFP to virgin females demonstrates that substituted trifluropropanones can indirectly stimulate egg development by inhibiting JHE activity in virgin females.
Subject(s)
Acetone/analogs & derivatives , Animals , Carboxylic Ester Hydrolases/antagonists & inhibitors , Chromatography, Thin Layer , Enzyme Inhibitors/pharmacology , Insecta/drug effects , Juvenile Hormones/metabolism , Nymph/drug effectsABSTRACT
Production of L-phenylacetylcarbinol (L-PAC) through biotransformation of benzaldehyde by free and immobilized cells of the yeast Saccharomyces cerevisiae has been attempted. L-PAC production was found to be maximum (0.4 microliter/ml) when anaerobically grown free cells were used as biocatalyst during aerobic biotransformation for two hours with magnetically stirred bioreactor. Growth under oxygen limited conditions led to accumulation of higher amount of pyruvate decarboxylase enzyme and co-substrate, pyruvate, resulting in higher L-PAC formation. L-PAC yield was low when biotransformations were carried out anaerobically either for aerobically or anaerobically grown free cells. Free cells were found to be more efficient biocatalyst for L-PAC production, as compared with the immobilized cells, with the investigated benzaldehyde concentration (0.3% v/v) and cell density (17.5% w/v). The study has explored and indicated the possibility of optimizing the yield of L-PAC by growing the yeast cells under oxygen limited condition for suitable aerobic mode of benzaldehyde biotransformation.