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The microscopic alga Coccomyxa subglobosa, collected from the Głowoniowa Nyża Cave (Tatra Mountains, Poland), is a source of fatty acids (FAs) that could be used for biodiesel production. FAs from subaerial algae have unlimited availability because of the ubiquity of algae in nature. Algal culture was carried out under laboratory conditions and algal biomass was measured during growth phase, resulting in 5 g of dry weight (32% oil). The fatty acid methyl ester (FAME) profile was analyzed by means of gas chromatography–mass spectrometry (GC–MS). The presence of lipids and chloroplasts in C. subglobosa was demonstrated using GC–MS and confocal laser microscopy. Naturally occurring FAMEs contained C12–C24 compounds, and methyl palmitate (28.5%) and methyl stearate (45%) were the predominant lipid species. Aerophytic algae could be an important component of biodiesel production, as they are omnipresent and environmentally friendly, contain more methyl esters than seaweed, and can be easily produced on a large scale.

A simple and rapid voltammetric method has been developed for the quantitative determination of a-tocopheryl acetate (a-TOAc) in pharmaceutical preparations. Studies with linear scan (LSV), square-wave (SQWV) and differential pulse voltammetry (DPV) were carried out using platinum microelectrodes. A well-defined, irreversible oxidation wave/peak was obtained at 1.30 V (vs. Ag/AgCl reference electrode.) The use of SQWV or DPV technique provides a precise determination of a-tocopheryl acetate using the multiple standard addition method. The statistical parameters and the recovery study data clearly indicate good reproducibility and accuracy of the method. Accuracy of the results assessed by recovery trials was found within the 99.3% to 103.5%, and 99.1% to 101.4%, for SQWV and DPV, respectively. The quantification limits for the both voltammetric techniques were found to be 6 Â 10 À5 M (SQWV) and 7 Â 10 À5 M (DPV). Analysis of the authentic samples containing a-TOAc showed no interference with common additives and excipients, such as unsaturated fatty acids (co-formulated as glycerine esters) and vitamin A (as retinol or b-carotene). The method proposed does not require any pretreatment of the pharmaceutical dosage forms. A gas chromatography determination of a-TOAc in real samples was also performed for comparison.Keywords: a-Tocopheryl acetate, Acetic acid, Microelectrodes, Linear scan voltammetry, Differential pulse voltammetry, Square-wave voltammetry Tocopherols, the main components of vitamin E, play vital roles in the biochemistry of living cells and exert relevant biological activities. It is commonly known that a-tocopherol (a-TOH) is the most biologically active component of vitamin E. Natural a-tocopherol, occurs only as d-atocopherol. Synthetic a-tocopherol, used as a food preservative, is a mixture of eight diastereoisomers, and is known as d, l-a-tocopherol. a-Tocopherol exists in nature as free alcohol (phenol). Unlike this, in pharmaceutical preparations used as supplements of vitamin E, a-tocopherol occurs in the form of more stable acetate, nicotinate or succinate esters, predominantly as all-rac-a-tocopheryl acetate. Esterification of a-TOH is assumed to cause biological inactivity, but the oral application of esters is fully effective. It is known from the literature [1] that they are easily hydrolyzed in the gut to the phenolic form. Usually, atocopheryl acetate (a-TOAc) is present in oil matrices, e.g., in peanut or olive oil. Among these components, b-carotene or retinol is also present in some vitamin E preparations.A survey of the literature revealed that there have been very few methods for the determination of a-TOAc, including gas chromatography (GC) with flame-ionization detection [2]. The methods based on high-performance liquid chromatography (HPLC) with fluorometric detection are recommended by Piironen [3] for separation and determination of a-TOAc. Only Brieskorn and Mahlmeister [4] proposed the voltammetric determination of aTOAc, which must be preceded by its hydrolysis ...