磺胺嘧啶在土壤及土壤组分中的吸附/解吸动力学

抗生素在土壤中的吸附/解吸及迁移过程受其理化性质的强烈影响,其中土壤中的矿物成分,如高岭石、蒙脱石及腐殖酸等是重要控制因素。本文主要研究了磺胺嘧啶在土壤、高岭石、蒙脱石和腐殖酸中的吸附/解吸动力学过程,并对反应前后的高岭石、蒙脱石和腐殖酸进行傅里叶红外光谱(Fourier transform infrared, FTIR)表征,探讨其可能的吸附机理。结果表明:磺胺嘧啶的吸附(解吸)动力学过程,可以分为快速吸附(解吸)、吸附解吸动态平衡和吸附(解吸)平衡3个阶段;磺胺嘧啶在土壤及其3种组分中的吸附(解吸)均可在24 h内达到平衡,其浓度高低会导致土壤及其组分的吸附差异,不同土壤组分中的官能团含量、带电性质及氢键是造成吸附差异的主要原因;分别用伪一级动力学模型、伪二级动力学模型和Elovich模型对其吸附过程进行拟合,其动力学吸附过程更符合伪二级动力学模型,R20.99,主要受控于物理化学吸附;FTIR图谱表明磺胺嘧啶与高岭石以物理吸附为主,并有少量氢键作用,与蒙脱石之间主要以氢键作用完成吸附,而在腐殖酸中存在表面络合和π–π共轭作用。     

Optimizing rice paddies’ lower greenhouse gas emissions and higher yield with SRI management under varying water table levels

Paddy and Water Environment - The System of Rice Intensification (SRI) is known as a climate-smart agricultural practice that increases rice production by changing the management of plants, soil,...     

An epidemic of canine rabies in Central Java, Indonesia

An epidemic of rabies in the province of Central Java, Indonesia, in 1985–1986 was investigated. Eighty-nine percent of confirmed cases occurred in dogs, 70% of which were domestically owned. While the number of cases clearly exceeded that normally expected and thus constituted an epidemic, the actual risk of human exposure to a rabid animal bite during the peak epidemic period was only 1.5 per million for females and 3.4 per million for males. Males between the ages of 5 and 14 years were the group at greatest risk of being exposed to the bite of a rabid dog. In the most seriously affected district, the risk of a dog contracting rabies was estimated to be 105 per 100 000 during the epidemic period. No cases were reported in wildlife. The results of the investigation suggest methods by which rabies could be eradicated from Java.     

Evaluation of the inhibitory activities of the extracts of Indonesian traditional medicinal plants against Plasmodium falciparum and Babesia gibsoni

Twenty-four kinds of water extracts derived from 22 plants that are traditionally used for the treatment of malaria on Java Island, Indonesia, were screened for their antibabesial and antimalarial activities. Among the extracts, 8 extracts displayed strong antimalarial activity, with an inhibition range from 89.6 to 100%, and 15 showed strong antibabesial activity, with an inhibition range from 84.2 to 98.1%. The extracts of Achillea millefolium, Baeckea frutenscens, Brucea javanica, Curcuma xanthorrhiza, Strychnos lucida and Swietenia macrophylla showed both strong antibabesial and antimalarial activities. The antimalarial activities paralleled the antibabesial activities, but the converse was not true.     

Tensile properties and water absorption of zein sheets plasticized with oleic and linoleic acids.

Corn zein has been investigated for fabrication of biodegradable packaging materials. Our objective was to investigate the effect of added plasticizers, oleic and linoleic acids, on tensile properties and water absorption of zein sheets. Moldable resins were precipitated from aqueous ethanol dispersions of zein and fatty acids and rolled into sheets of approximately 0.5 mm in thickness. To increase plasticization effects, zein-oleic acid sheets were replasticized by heating them in fatty acid baths. Plasticization resulted in flexible sheets of high clarity, low modulus, and high elongation and toughness, although low tensile strength. Water absorption of zein sheets was lowered by plasticization, attributed in part to reduced mass fraction of zein. Polymerization of linoleic acid may have sealed off pores on sheet surfaces, thus slowing water absorption.     

Expression of somatic embryogenesis-related genes in sugarcane (Saccharum officinarum L.)

Journal of Crop Science and Biotechnology - The low frequency of plantlet regenerates from the somatic embryogenesis (SE) callus in sugarcane becomes a problem to produce its seed. Plant growth...     

Impact of transgenic sugarcane overexpressing SoSPS1 gene on bacterial diversity,enzyme activity and minerals content in soil rhizosphere

Journal of Crop Science and Biotechnology - The transgenic sugarcane overexpressing SoSPS1 gene increased sugar content which may alter the root exudation that interact with soil rhizosphere...     

Genetic diversity of rice germplasm (Oryza sativa L.) of java island,Indonesia

Journal of Crop Science and Biotechnology - The role of genetic diversity in crop germplasm is an important concept within genetic conservation. In this research, 43 accessions were analyzed at the...     

Nanoemulsions of cancer chemopreventive agent benzyl isothiocyanate display enhanced solubility, dissolution, and permeability

Benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, is an effective chemopreventive agent. The objective of this study was to develop nanoemulsion formulations for the oral delivery of BITC. Optimized oil-in-water BITC nanoemulsions were prepared by a spontaneous self-nanoemulsification method and a homogenization-sonication method. Both nanoemulsions entrapped high amounts of BITC (15-17 mg/mL), with low polydispersity and good colloidal stability. The BITC nanoemulsions showed enhanced solubility and dissolution compared to pure BITC. These formulations markedly increased the apical to basolateral transport of BITC in Caco-2 cell monolayers. The apparent permeability values were 3.6 × 10(-6) cm/s for pure BITC and (1.1-1.3) × 10(-5) cm/s for BITC nanoemulsions. The nanoemulsions were easily taken up by human cancer cells A549 and SKOV-3 and inhibited tumor growth in vitro. This work shows for the first time that BITC can be formulated into nanoemulsions and may show promise in enhancing absorption and bioavailability.     

Insights into sorption and leaching behavior of sulfadiazine in soil as affected by humic acid

Journal of Soils and Sediments - Sulfonamides with high mobility in the soil pose a significant threat to environmental ecology and human health. Organic matter is known to affect the sorption and...