Nanoferrites heterogeneous catalysts for biodiesel production from soybean and canola oil: a review.

Fossil fuel depletion and pollution are calling for alternative, renewable energies such as biofuels. Actual challenges include the design of efficient processes and catalysts to convert various feedstocks into biofuels. Here, we review nanoferrites heterogeneous catalysts to produce biodiesel from soybean and canola oil. For that, transesterification is the main synthesis route and offers simplicity, cost-effectiveness, better process control, and high conversion yield. Catalysis with nanoferrites and composites allow to obtain yields higher than 95% conversion with less than 5.0 wt.% of catalyst loading at 80 °C in 1-2 h. More than 90% conversion yields can be achieved with a moderate alcohol/oil molar ratio, i.e., between 12:1 to 16:1. Catalyst recovery is easy due to the magnetic properties of nanoferrite, which can be effectively reused up to 4 times with less than 10% loss of catalytic efficiency.

Bioassay of nystatin: measurement of Mg2+ efflux by atomic-absorption spectroscopy.

A rapid bioassay for the polyene antibiotic nystatin, based on the leakage of Mg(2+) from sensitive cells of Saccharomyces cerevisiae, is described. The assay employs atomic-absorption spectrophotometry to measure the Mg(2+) leaked. It compares favourably with the classical method of diffusion on an agar-plate, in terms of speed, reproducibility and convenience.

Manufacturing blood ex vivo: a futuristic approach to deal with the supply and safety concerns.

Blood transfusions are routinely done in every medical regimen and a worldwide established collection, processing/storage centers provide their services for the same. There have been extreme global demands for both raising the current collections and supply of safe/adequate blood due to increasingly demanding population. With, various risks remain associated with the donor derived blood, and a number of post collection blood screening and processing methods put extreme constraints on supply system especially in the underdeveloped countries. A logistic approach to manufacture erythrocytes ex-vivo by using modern tissue culture techniques have surfaced in the past few years. There are several reports showing the possibilities of RBCs (and even platelets/neutrophils) expansion under tightly regulated conditions. In fact, ex vivo synthesis of the few units of clinical grade RBCs from a single dose of starting material such as umbilical cord blood (CB) has been well established. Similarly, many different sources are also being explored for the same purpose, such as embryonic stem cells, induced pluripotent stem cells. However, the major concerns remain elusive before the manufacture and clinical use of different blood components may be used to successfully replace the present system of donor derived blood transfusion. The most important factor shall include the large scale of RBCs production from each donated unit within a limited time period and cost of their production, both of these issues need to be handled carefully since many of the recipients among developing countries are unable to pay even for the freely available donor derived blood. Anyways, keeping these issues in mind, present article shall be focused on the possibilities of blood production and their use in the near future.

Therapeutic biology of Jatropha curcas: a mini review.

Jatropha curcas is a drought resistant, perennial plant that grows even in the marginal and poor soil. Raising Jatropha is easy. It keeps producing seeds for many years. In the recent years, Jatropha has become famous primarily for the production of biodiesel; besides this it has several medicinal applications, too. Most parts of this plant are used for the treatment of various human and veterinary ailments. The white latex serves as a disinfectant in mouth infections in children. The latex of Jatropha contains alkaloids including Jatrophine, Jatropham and curcain with anti-cancerous properties. It is also used externally against skin diseases, piles and sores among the domestic livestock. The leaves contain apigenin, vitexin and isovitexin etc. which along with other factors enable them to be used against malaria, rheumatic and muscular pains. Antibiotic activity of Jatropha has been observed against organisms including Staphylococcus aureus and Escherichia coli. There are some chemical compounds including curcin (an alkaloid) in its seeds that make it unfit for common human consumption. The roots are known to contain an antidote against snake venom. The root extract also helps to check bleeding from gums. The soap prepared from Jatropha oil is efficient against buttons. Many of these traditional medicinal properties of Jatropha curcas need to be investigated in depth for the marketable therapeutic products vis-à-vis the toxicological effects thereof. This mini review aims at providing brief biological significance of this plant along with its up-to-date therapeutic applications and risk factors.

On the uptake of nystatin by Saccharomyces cerevisiae 3. Electrochemistry of the yeast cell surface.

The electrophoretic behaviour of fresh and liquid nitrogen stored inocula of Saccharomyces cerevisiae has been studied as a function of pH, ionic strength, buffer composition, growth temperature of the inoculum, number of washings of the inoculum prior to electrophoretic investigation, growth medium used in the preparation of the inoculum, interaction of the inoculum with nystatin, and interaction of the inoculum with calcium ions. The results provide a basis for a discussion of the role of the yeast cell surface in the mode of action of nystatin (a polyene antibiotic), on interaction with sensitive Saccharomyces cerevisiae cells. They indicate the profound importance of the cell surface in the interaction with the antibiotic. Moreover, the results of the temperature growth/electrophoresis experiments support the view that a sharp change in membrane fluidity occurs in the yeast membrane. The results are also discussed in the light of those reported in previous papers on the interaction of yeast cells with nystatin.

On the uptake of nystatin by Saccharomyces cerevisiae. 1 Basic considerations.

The uptake of nystatin by sensitive Saccharomyces cerevisiae cells has been studied as a function of temperature and nystatin concentration. Following analysis of the data, kinetic rate constants and a monolayer capacity are calculated. This shows that c 13 X more nystatin is taken up than can be supported by the cell surface. The process is accompanied by an activation energy of 41.6 kJ mol-1. It is suggested that these data support a rapid uptake process onto the cell wall followed by a slower diffusion process through the wall to the membrane.

On the uptake of nystatin by Saccharomyces cerevisiae. 2 Effects of pH, ionic strength, sterol concentration and "protecting" ions.

Uptake of nystatin by sensitive cells of Saccharomyces cerevisiae was studied as a function of pH and ionic strength. The pH was shown to affect radically uptake kinetics and extent, whilst ionic strength variation appeared not to modify uptake at all. The effects of variation in the sterol concentration of the cells employed showed a decrease in nystatin uptake as sterol concentration increased. This was not the anticipated observation. Calcium ions were shown to "protect" the yeast cells by associating with the cell and not the antibiotic. Possible explanations are discussed.

On the uptake of nystatin by saccharomyces cerevisiae. 5 The release of amino acids.

The release of amino acids from Saccharomyces cerevisiae under the action of nystatin has been studied. The kinetic results do not show any dependence upon molecular size but do support earlier results suggesting that interactions depend upon slow diffusion processes through the cell wall. The effects of temperature, sterol concentration and the presence of calcium ion have also been investigated.