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Renewable feedstock from perennial industrial crops, including those cultivated on marginal land in a short-rotation coppice system, could be an important contribution to the bioeconomy. The majority of data available on the topic are limited to the production of bioenergy from this type of biomass. According to the concept of bioeconomy, biomass-based bioproducts have priority over energy production. This paper characterizes the chemical composition and antioxidant activity of extracts from bark (b), wood (w) or a mixture of bark and wood (b + w) from Salix purpurea, Salix viminalis and Populus nigra obtained using supercritical carbon dioxide (scCO2), scCO2 and water (1%, w/w) or only water. Generally, a high concentration of polyphenols was obtained after extraction with scCO2 and water, while the lowest concentration was found in extracts obtained with scCO2. The highest concentration of polyphenols (p < 0.05) was obtained in an extract from P. nigra (b) (502.62 ± 9.86 mg GAE/g dry matter (d.m.)) after extraction with scCO2 and water, whereas the lowest polyphenol concentration was observed in an scCO2 extract from S. purpurea (b) (6.02 ± 0.13 mg GAE/g d.m.). The flavonoids were effectively separated by extraction with scCO2 (0.88–18.37 mg QE/g d.m.). A positive linear relationship between the antioxidant activity determined by DPPH and ABTS assays and the concentration of polyphenols was demonstrated, R2 = 0.8377 and R2 = 0.9568, respectively. It is most probable that the concentration of flavonoids, rather than the concentration of polyphenols, determines the chelating activity of Fe2+. The Fe2+-chelating activity of scCO2 extracts ranged from 75.11% (EC50 = 5.41 mg/cm3, S. purpurea, b + w) to 99.43% (EC50 = 0.85 mg/cm3, P. nigra, b + w). The lowest chelating activity was demonstrated by the extracts obtained with scCO2 and water (maximum 26.36%, S. purpurea, b + w). In extracts obtained with scCO2 and water, p-hydroxybenzoic acid (210–428 µg/g), p-coumaric acid (56–281 µg/g), saligenin (142–300 µg/g) and salicortin (16–164 µg/g) were the dominant polyphenols. All of these chemical compounds occurred mainly in the free form. The S. purpurea, S. viminalis and P. nigra biomass proved to be an attractive source of biologically active compounds for various possible applications in food, drugs or cosmetics. These compounds could be extracted using an environmentally friendly method with scCO2 and water as a co-solvent.

Wheat storage proteins and products of their hydrolysis may cause coeliac sprue in genetically predisposed individuals with high expression of main histocompatibility complex HLA-DQ2 or DQ8, since by consuming wheat, they become exposed to proline- (P) and glutamine (Q)-rich gluten. In bread-making, the hydrolysis of gliadins and coeliac-toxic peptides occurs with varied efficiency depending on the fermentation pH and temperature. Degradation of gliadins catalysed by Lactobacillus acidophilus 5e2 peptidases and a commercial prolyl endopeptidase synthesised by A. niger, carried out at pH 4.0 and 37 &deg, C, reduces the gliadin concentration over 110-fold and decreases the relative immunoreactivity of the hydrolysate to 0.9% of its initial value. Hydrolysis of coeliac-toxic peptides: LGQQQPFPPQQPY (P1) and PQPQLPYPQPQLP (P2) under the same conditions occurs with the highest efficiency, reaching 99.8 &plusmn, 0.0% and 97.5 &plusmn, 0.1%, respectively. The relative immunoreactivity of peptides P1 and P2 was 0.8 &plusmn, 0.0% and 3.2 &plusmn, 0.0%, respectively. A mixture of peptidases from L. acidophilus 5e2 and A. niger may be used in wheat sourdough fermentation to reduce the time needed for degradation of proteins and products of their hydrolysis.

In this study, evening primrose oil (EPO), rich in γ-linoleic acid (GLA) in the sn-2 position was used as a substrate for the synthesis of structured triacylglycerols (sTAG) of the MLM-type (bearing a medium chain fatty acid in the sn-1- and -3-positions and a long chain fatty acid in the sn-2-position). The highest yield of sTAG by interesterification with tricapyrlin was 23 and 28% for Rhizopus delemar lipase (RDL) and Rhizomucor miehei lipase (RML), respectively. In an acidolysis using caprylic acid, methyl-tert-butyl ether (MTBE) was preferred over hexane and also the yield was higher than in interesterification and reached 32–38% for RDL and 25–28% for RML. Alternatively, a two-step method was used, in which first 2-MAG could be best obtained in MTBE at an initial water activity of aw = 0.11. In the ethanolysis of EPO catalyzed by RDL, 2-MAG was obtained, which contained about 78% of GLA. After isolation of the 2-MAG, the highest content of 79% sTAG of the MLM-type was obtained then by esterification of 2-MAG rich in GLA with caprylic acid. This reaction was catalyzed by RDL in n-hexane at a molar ratio of caprylic acid to 2-MAG of 3:1. All biocatalytic reactions were also performed with recycling of the lipase, but after several consecutive batches the activity of the lipase was decreased mostly due to mechanical instability of the carrier material. Practical applications: The presented methods of medium engineering enable sTAGs to be synthesized using a natural substrate (EPO, Oenothera biennis L.). Especially the two-step method enables a high yield synthesis of sTAG containing γ-linoleic acid in the sn-2 position and the medium-chain caprylic acid in the sn-1 and sn-3 positions. This sTAG is rare in nature and the chemical synthesis is cumbersome. This sTAG could be applied in human nutrition as low-calorie fat with a beneficial effect on human health because of the high content of the polyenoic GLA.

Synthesis of biodiesel is performed mainly by chemical catalysis, but can also be performed by enzymatic or microbial methods, and these might play an important role in future substitution of petroleum-based diesel. To discover sustainable, economically attractive biotechnological processes for biodiesel synthesis, close cooperation between different disciplines is needed. Currently, lipases are the enzymes of choice for the synthesis of fatty acid esters (FAE) from fats and oils, yielding biodiesel with the methyl esters (FAME) as the most important product. More recently, the direct production of FAE using engineered whole cell microorganism has also been described (MicroDiesel). Current enzymatic processes are still hampered by the high costs of the biocatalyst, but significant progress has recently been made leading to the first industrial enzymatic biodiesel production. Enzymatic biodiesel production is mostly attractive because of the starting materials (waste frying oils, oils with high water content, etc.), for which conventional chemical interesterification can hardly be applied.

Lipase catalyzed-synthesis of ascorbyl oleate was performed in ionic liquids with addition of salt hydrate pairs for water activity control. The highest yield in the synthesis of ascorbyl oleate (72%) was obtained in [BMIM][BF 4 ] in the presence of the salt pair NaI 2/0, which corresponds to a water activity of 0.3. Purity and chemical identity of 6- O -ascorbyl oleate was confirmed by 1 H and 13 C NMR analysis.

In this review, the occurrence, properties, nutritional importance and especially biotechnological methods for the production of conjugated linoleic acids (CLA) and CLA-rich lipids are summarized. Beside information from medical and nutritional studies on the biological activity of CLA, the focus is on the enzymatic synthesis of structured lipids containing CLA and the microbial synthesis of CLA.

The lipase-catalyzed synthesis of ascorbyloleate was studied using different preparations of lipases from Candida antarctica. Conversion to ascorbyloleate was influenced by the type of lipase, the carrier used for immobilization, water activity and organic solvent. The highest conversion (63%) was found using Chirazyme L-2 immobilized on carrier C2, in acetone, using methyloleate as acyl donor (4-fold excess), at water activity 0.11 and in the presence of molecular sieves.

The aim of this investigation was to obtain an efficiently immobilized intracellular lipase from Rhizomucor miehei and Yarrowia lipolytica . The activity of intracellular lipases from R. miehei and Y. lipolytica was enhanced by the addition of waste fats (beef tallow or poultry fat) to the medium and by cell immobilization on biomass support particles (BSPs, cubic particle of polypropylene or polyurethane foams). The highest intracellular activity of lipases was obtained after adding 20 and 50 BSPs to the medium of R. miehei (130.5 U) and Y. lipolytica (90.3 U), respectively. The best carrier for immobilizing intracellular lipases was polyurethane foam and the lipolytic activity of immobilized lipases was 2.1–4.3-times higher than the activity of lipases obtained from free biomass. The properties of the immobilized enzymes were very similar to the free enzymes but the immobilized intracellular lipases were more useful for the hydrolysis of waste fats. The highest reaction ratio (72%) and content of free fatty acids (68% (w/w)) in the reaction mixture was obtained after 72 h for beef tallow hydrolysis in a batch reaction with the immobilized lipases from R. miehei.

Candida antarctica synthesised surface-active mannosylerythritol lipids at 46 g l−1 by adding 80 g soybean oil l−1 to the medium and maintaining the pO2 at 50% with an air flow rate 1 vvm. Two-stage culturing of C. antarctica avoided medium foaming but the yield of biosurfactants synthesis was 28 g l−1. The biosurfactants decreased the surface tension of water to 35 mN m−1.

S t r e s z c z e n i e Nanotechnologia to jedna z nowatorskich technologii obejmująca charakterystyke, wytwarzanie i/lub sterowanie strukturami, urządzeniami lub materialami, w ktorych co najmniej jeden wymiar wynosi od 1 do 100 nanometrow [12]. W pracy przedstawiono osiągniecia nanotechnologii i mozliwości jej zastosowania w przemyśle spozywczym. Omowiono zagadnienia związane glownie z podwyzszaniem jakości zywności, rozwojem inteligentnej zywności i opakowan, jak rowniez wykorzystaniem nanosensorow do wykrywania zanieczyszczen bakteryjnych i obecności pestycydow. Zasygnalizowano ryzyko stosowania nanomaterialow dla zdrowia czlowieka i środowiska. Przedstawiono takze regulacje prawne i wskazano na koniecznośc ich dostosowania do specyfiki nanomaterialow. Slowa kluczowe: nanotechnologia, nanozywnośc, nanostruktury, biosensory

Ser edamski solono w zmodyfikowanej solance skladającej sie z mieszaniny NaCl i KCl w proporcji 1:1,27 (w/w) przez 12, 18 i 24 h oraz w solance tradycyjnej (zawierającej wylącznie chlorek sodu) przez 24 h. Otrzymane sery oceniano sensorycznie oraz oznaczano kwasowośc czynną, zawartośc wody i NaCl, ogolną liczbe bakterii, liczbe paciorkowcow kwaszących, liczbe E. coli oraz NPL bakterii sacharolitycznych. Zawartośc wody i kwasowośc czynna serow byly prawidlowe i charakterystyczne dla sera edamskiego. Na poziom NaCl w serach wplywal istotnie zmodyfikowany sklad solanki, a takze czas solenia. Sery otrzymane po soleniu w tradycyjnej solance przez 24 godziny zawieraly maksymalnie 1,10% NaCl. W serze solonym w solance zmodyfikowanej stwierdzono istotnie statystycznie mniejszą w porownaniu z serami solonymi w solance tradycyjnej zawartośc soli, ktora wynosila od 0,68 do 1,04%. W serach o zmniejszonej zawartości NaCl stwierdzono niewielkie zwiekszenie liczby paciorkowcow kwaszących. We wszystkich serach najbardziej prawdopodobna liczba bakterii sacharolitycznych utrzymywala sie na zblizonym poziomie. Nie stwierdzono wzrostu liczby E. coli w serach solonych w solance zmodyfikowanej, bez wzgledu na czas solenia. Analiza sensoryczna potwierdzila dobrą jakośc serow uzyskanych po krotszym czasie solenia w solance zawierającej NaCl i KCl.

The highest yields of biosurfactants were obtained by: (i) Pseudozyma antarctica (107.2 g L−1) cultivated in a medium containing post-refining waste; (ii) Pseudozyma aphidis (77.7 g L−1); and (iii) Starmerella bombicola (93.8 g L−1) both cultivated in a medium with soapstock; (iv)Pichia jadinii (67.3 g L−1) cultivated in a medium supplemented with waste frying oil. It was found that the biosurfactant synthesis yield increased in all strains when the cell surface hydrophobicity reached 70–80 %, enabling the microbial cells to make good contact with hydrophobic substrates. The lowest surface tension of the post-cultivation medium was from 32.0 mN m−1 to 37.8 mN m−1. However, this parameter (which was also determined by a drop collapse assay) was of limited use in monitoring biosurfactant synthesis in this study. The crude glycerol was not a good substrate for biosurfactant synthesis although, in the case of P. aphidis, 67.4 g L−1 of biosurfactants were obtained after cultivation in the medium supplemented with glycerol fraction (GF2). In a low-cost medium containing soapstock and whey permeate or molasses, about 90 g L−1 of mannosylerythritol lipids were synthesised by P. aphidis and approximately 40 g L−1 by P. antarctica.

The possibility of producing monoacyloglycerols (MAGs) from poultry fat or beef tallow using selected microorganisms or enzymatic glycerolysis was established. The highest content of MAGs (16.21–17.63% w/w) in the lipids was obtained after the cultivation of Candida lipolytica on a medium with poultry fat. The concentration of MAGs in the lipids which remained in the medium was influenced by the microorganisms strains and their cultivation conditions. The yield of MAGs obtained by the enzymatic glycerolysis of poultry fat or beef tallow ranged from 3.52% to 55.10% w/w, respectively.

Aspergillus niger, Geotrichum candidum and Mucor miehei, when grown on a medium containing beef tallow or poultry fat for 5 days at 28°C, in Roux bottles, shake-flasks or fermenters, synthesized from 0.4 to 3.2 g lipids/I. The degree of fat utilization varied from 15 to 70%. The type of fat in the medium, the species of fungi and its cultivation method all influenced the fatty acid composition of fats remaining in the medium, as well as the intracellular lipids of the fungi.

The paper presents the results of investigations into the technological possibilities of controlling the transgalactosylation process of lactose in permeate after whey ultrafiltration in order to improve the efficiency of galactooligosaccharides or lactulose synthesis. The synthesis efficiency was influenced by the selection of a β-galactosidase preparation, substrate concentration and, in the synthesis of lactulose, also by the ratio of lactose and fructose added to the reaction mixture. The obtained synthesis efficiency of GOS and, most of all, of lactulose (65 g L−1), may be found satisfactory. The study also resulted in a proposed GOS or lactulose concentrates (concentrated or dried) production technology using permeate after ultrafiltration of milk or whey as lactose sources.

Candida antarctica or Candida apicola synthesized surfactants (glycolipids) in the cultivation medium supplemented with oil refinery waste, either with soapstock (from 5.0% to 12.0% v/v) or post-refinery fatty acids (from 2.0% to 5.0% v/v). The efficiency of glycolipids synthesis was determined by the amount of waste supplemented to the medium and was from 7.3 to 13.4 g/l and from 6.6 to 10.5 g/l in the medium supplemented with soapstock and post-refinery fatty acids, respectively. The studied yeast also synthesized glycolipids in the non-supplemented medium however, by the enrichment of medium with the oil refinery waste, a 7.5-8.5-fold greater concentration of glycolipids was obtained in the post-culture liquid then in the medium without addition of oil refinery waste. The yeast synthesized from 6.6 to 10.3 g dry biomass/l and the intra-cellular fat content was from 16.8% to 30.2%. The efficiency of glycolipids synthesis was determined by yeast species, medium acidity and culture period. The surface tension of the post-culture liquid separated from yeast biomass was reduced to 35.6 mN/m, which corresponded to the surface tension obtained at the critical micelle concentration of glycolipids.

Publisher Summary This chapter determines the growth conditions for C. antarctica in the fermentor as well as their effect on the yield of biosynthesis and properties of mannosylerythritol lipids (MELs). During the synthesis of surface-active substances, oxygenation is of great importance because it influences the growth conditions of microorganisms hence yield of surfactant synthesis. Moreover, intensive aeration of cultivation medium, which has a low surface tension, causes an intensive foaming of the medium. It is important problem in the process. Based on the studies, it was found that the rate of airflow through the medium was a critical variable that influenced the intensity of foaming of the medium and yield of biosurfactant synthesis. However, the same intensity of medium oxygenation (50%) could be achieved, by maintaining the airflow rate at the level one or two vvm, using the so-called active regulation of stirrer revolutions. It is found that the greatest yields of glycolipids synthesis could be obtained at the airflow rate of one wm independent from carbon source, although, at the airflow rate two vvm, relatively slightly greater yield of biosurfactant was obtained in the medium with glucose.