In line with the growing interest in humans' nutrition, production of microalgae-based functional foods characterized by an increased content of bioactive substances is attractive. The aim of this study was to investigate the potential of microalgae as additives to feed for laying hens, to enrich the eggs with polyunsaturated fatty acids (PUFA) and selenium/carotenoid antioxidants. Our results showed that supplementation of hens by feed containing 1% of Trachydiscus minutus or 1% of Japonochytrium marinum leads to increase of long-chain PUFA in eggs by 26-66%. Addition of 1% of Scenedesmus obliquus to feed causes the increase of lutein and cantaxanthin in eggs by 48% and 18%, respectively, and addition of 0.5% selenium enriched Chlorella vulgaris increases the final content of organic selenium in eggs by 100-152%. As concerns selenium, it is important to notice that its bioavailability has to be considered. Despite the higher concentration of total selenium in Vischeria helvetica than in C. vulgaris, its bioaccessibility in Vischeria was limited, thus out of usage for feeding purposes. Administration of combinations of selenium enriched Chlorella + Japonochytrium and Chlorella + Schizochitrium verified the increased concentrations of organic selenium, PUFA, as well as carotenoids, with no adverse effect on quality and productivity of eggs. The study confirmed the potential of both traditional as well as new microalgae to be used as feed supplements for functional eggs production. The supplementation of hens by specific microalgae combinations could be advantageous in terms of spectrum of bioactive compounds present.

• Klíčová slova
• Carotenoids, Eggs, Feed, Microalgae, Polyunsaturated fatty acids, Selenium,
• Publikační typ
• časopisecké články MeSH

Polyunsaturated fatty acids of the n-3 series (n-3 PUFA) exhibit a number of favorable effects on the human organism and it is desirable to increase their intake in the diet. For this purpose, flaxseed oil was added to a chicken-feed mixture for the production of meat and eggs. The content of n-3 PUFA in the obtained meat was increased from 250 mg (reference value) to 900 mg in 100 g of meat and from 110 mg (reference value) to 190 mg in 100 g of whole egg; the enriched products are designated as omega-3 meat and omega-3 eggs. Omega-3 meat and eggs were subsequently fed for a period of eight weeks in an amount of 480 g of meat and four eggs (228 g netto) a week to a group of 14 healthy volunteers, whose body composition parameters were measured and blood was analyzed biochemically to determine blood lipids, coagulation parameters, plasma, and erythrocyte fatty acid spectrum composition. A control group of 14 volunteers was fed normal chicken and eggs in the same regime. The performed dietary intervention increases the intake of long-chain PUFA (LC-PUFA) by 37 mg per day, which represents 7-15% of the recommended daily dose. The performed tests demonstrated that the consumption of omega-3 enriched meat and eggs significantly increases the content of n-3 PUFA in the erythrocytes, which are a long-term indicator of fatty acid intake. This intervention has no demonstrable effect on the basic body parameters, such as body weight, fat content, Body Mass Index (BMI), and also on the plasma cholesterol level, high-density lipoprotein (HDL), low-density lipoprotein (LDL), blood clotting and inflammation markers, and omega-3 index.

• Klíčová slova
• blood coagulation, blood lipids, body composition, erythrocytes, fatty acids spectrum, n-3 polyunsaturated fatty acids, omega-3 diet,
• MeSH
• dieta metody   MeSH
• dospělí MeSH
• erytrocyty chemie   MeSH
• fortifikované potraviny * MeSH
• index tělesné hmotnosti MeSH
• jednoduchá slepá metoda MeSH
• kardiovaskulární nemoci prevence a kontrola   MeSH
• lidé MeSH
• lipoproteiny HDL krev   MeSH
• lipoproteiny LDL krev   MeSH
• maso MeSH
• mastné kyseliny krev   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• omega-3 mastné kyseliny aplikace a dávkování   MeSH
• rizikové faktory kardiovaskulárních chorob MeSH
• vejce MeSH
• zdraví dobrovolníci pro lékařské studie MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• lipoproteiny HDL MeSH
• lipoproteiny LDL MeSH
• mastné kyseliny MeSH
• omega-3 mastné kyseliny MeSH

Acquisition of genes by plastid genomes (plastomes) via horizontal gene transfer (HGT) seems to be a rare phenomenon. Here, we report an interesting case of HGT revealed by sequencing the plastomes of the eustigmatophyte algae Monodopsis sp. MarTras21 and Vischeria sp. CAUP Q 202. These plastomes proved to harbour a unique cluster of six genes, most probably acquired from a bacterium of the phylum Bacteroidetes, with homologues in various bacteria, typically organized in a conserved uncharacterized putative operon. Sequence analyses of the six proteins encoded by the operon yielded the following annotation for them: (i) a novel family without discernible homologues; (ii) a new family within the superfamily of metallo-dependent hydrolases; (iii) a novel subgroup of the UbiA superfamily of prenyl transferases; (iv) a new clade within the sugar phosphate cyclase superfamily; (v) a new family within the xylose isomerase-like superfamily; and (vi) a hydrolase for a phosphate moiety-containing substrate. We suggest that the operon encodes enzymes of a pathway synthesizing an isoprenoid-cyclitol-derived compound, possibly an antimicrobial or other protective substance. To the best of our knowledge, this is the first report of an expansion of the metabolic capacity of a plastid mediated by HGT into the plastid genome.

• Klíčová slova
• Eustigmatophyceae, UbiA superfamily, horizontal gene transfer, plastid genome, secondary metabolism, sugar phosphate cyclase superfamily,
• MeSH
• anotace sekvence MeSH
• bakteriální geny MeSH
• DNA řas genetika   MeSH
• genom plastidový * MeSH
• Heterokontophyta genetika   MeSH
• molekulární evoluce MeSH
• multigenová rodina MeSH
• přenos genů horizontální * MeSH
• sekvenční analýza DNA metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA řas MeSH

Algae are becoming a strategic source of fuels, food, feedstocks, and biologically active compounds. This potential has stimulated the development of innovative analytical methods focused on these microorganisms. Algal lipids are among the most promising potential products for fuels as well as for nutrition. The crucial parameter characterizing the algal lipids is the degree of unsaturation of the constituent fatty acids quantified by the iodine value. Here we demonstrate the capacity of the spatially resolved Raman microspectroscopy to determine the effective iodine value in lipid storage bodies of individual living algal cells. The Raman spectra were collected from three selected algal species immobilized in an agarose gel. Prior to immobilization, the algae were cultivated in the stationary phase inducing an overproduction of lipids. We employed the characteristic peaks in the Raman scattering spectra at 1,656 cm(-1) (cis C═C stretching mode) and 1,445 cm(-1) (CH(2) scissoring mode) as the markers defining the ratio of unsaturated-to-saturated carbon-carbon bonds of the fatty acids in the algal lipids. These spectral features were first quantified for pure fatty acids of known iodine value. The resultant calibration curve was then used to calculate the effective iodine value of storage lipids in the living algal cells from their Raman spectra. We demonstrated that the iodine value differs significantly for the three studied algal species. Our spectroscopic estimations of the iodine value were validated using GC-MS measurements and an excellent agreement was found for the Trachydiscus minutus species. A good agreement was also found with the earlier published data on Botryococcus braunii. Thus, we propose that Raman microspectroscopy can become technique of choice in the rapidly expanding field of algal biotechnology.

• Klíčová slova
• Raman spectroscopy, algal cells, iodine value, lipids,
• MeSH
• analýza jednotlivých buněk metody   MeSH
• biopaliva MeSH
• Chlorophyta chemie   cytologie   MeSH
• jod analýza   MeSH
• mikrořasy chemie   cytologie   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• Ramanova spektroskopie metody   MeSH
• reprodukovatelnost výsledků MeSH
• tuky nenasycené chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biopaliva MeSH
• jod MeSH
• tuky nenasycené MeSH