Abstract: Microalgae are tiny photosynthetic plants. Nowadays, microalgae are being used as nutrient-dense foods and sources of fine chemicals. They have significant amounts of lipid, carotenoids, vitamins, protein, minerals, chlorophyll, and pigments. Oil extraction from algae is a hotly debated topic currently because introducing an efficient method could decrease the process cost. This can determine the sustainability of algae-based foods. Scientific research works show that solvent extraction using chloroform/methanol (2:1) mixture is one of the efficient methods for oil extraction from algal cells, but both methanol and chloroform are toxic solvents, and therefore, the extracted oil will not be suitable for food application. In this paper, the effect of two food grade solvents (hexane and hexane/ isopropanol) on oil extraction yield from microalgae Dunaliella sp. was investigated and the results were compared with chloroform/methanol (2:1) extraction yield. It was observed that the oil extraction yield using hexane, hexane/isopropanol (3:2) and chloroform/methanol (2:1) mixture were 5.4, 13.93, and 17.5 (% w/w, dry basis), respectively. The fatty acid profile derived from GC illustrated that the palmitic (36.62%), oleic (18.62%), and stearic acids (19.08%) form the main portion of fatty acid composition of microalgae Dunalliela sp. oil. It was concluded that, the addition of isopropanol as polar solvent could increase the extraction yield significantly. Isopropanol solves cell wall phospholipids and enhances the release of intercellular lipids, which improves accessing of hexane to fatty acids.
Abstract: Dietary cholesterol has elicited the most public
interest as it relates with coronary heart disease. Thus, humans have
been paying more attention to health, thereby reducing consumption
of cholesterol enriched food. Egg is considered as one of the major
sources of human dietary cholesterol. However, an alternative way to
reduce the potential cholesterolemic effect of eggs is to modify the
fatty acid composition of the yolk. The effect of palm oil (PO),
soybean oil (SO), sesame seed oil (SSO) and fish oil (FO)
supplementation in the diets of layers on egg yolk fatty acid,
cholesterol, egg production and egg quality parameters were
evaluated in a 42-day feeding trial. One hundred and five Isa Brown
laying hens of 34 weeks of age were randomly distributed into seven
groups of five replicates and three birds per replicate in a completely
randomized design. Seven corn-soybean basal diets (BD) were
formulated: BD+No oil (T1), BD+1.5% PO (T2), BD+1.5% SO (T3),
BD+1.5% SSO (T4), BD+1.5% FO (T5), BD+0.75% SO+0.75% FO
(T6) and BD+0.75% SSO+0.75% FO (T7). Five eggs were randomly
sampled at day 42 from each replicate to assay for the cholesterol,
fatty acid profile of egg yolk and egg quality assessment. Results
showed that there were no significant (P>0.05) differences observed
in production performance, egg cholesterol and egg quality
parameters except for yolk height, albumen height, yolk index, egg
shape index, haugh unit, and yolk colour. There were no significant
differences (P>0.05) observed in total cholesterol, high density
lipoprotein and low density lipoprotein levels of egg yolk across the
treatments. However, diets had effect (P
Abstract: The aim of this trial was to evaluate fatty acid profile of meat from lambs fed on diets containing 0, 12.5 and 25.0% mulberry hay as a substitute for the concentrate. Twenty-four feedlot Ile de France lambs (average weight of 15kg and average age of 60 days) were randomized to receive the different diets and slaughtered at 32kg body weight. Increases were observed in the concentrations of the saturated pentadecanoic, heptadecanoic and arachidic fatty acids; of the monounsaturated nervonic fatty acid and of the polyunsaturated α-linolenic, ɣ-linolenic and eicosapentaenoic fatty acids. Increased conjugated linoleic acid (CLA) was also found in the meat of lambs fed on 12.5% mulberry hay. In addition, the omega-3 composition was augmented, while the omega-3/omega-6 ratio was decreased in mulberry hay-fed animals. In conclusion, a more desirable fatty acid profile was observed in lamb meat following the substitution of mulberry hay in the concentrate of fed, resulting in improved nutritional characteristics of the meat.
Abstract: The objective of this study was to investigate the effect of tropical forage source and feeding system on fatty acid composition and antioxidant activity in meat goats. Twenty male crossbred goats (Boer x Saanen), were included in the current study and the study design was assigned to be a 2 x 3 factorial in completely randomized design. All goats were slaughtered after 120 days of experimental period. Dietary tropical roughage sources were grass (Mulata II) and legume (Verano stylo). Both types of roughage were offered to the experimental meat goat as 3 feeding regimes; cut-and-carry, silage and grazing. All goats were fed basal concentrate diet at 1.5% of body weight, and they were fed ad libitum the roughages.Chemical composition, fatty acid profile and antioxidation activity of dietary treatments in all feeding system and longissimus dorsi (LD) muscles in all groups were quantified. The results have shown that the fat content in both types of studied roughage sources ranged from about 2.0% to 4.0% of DM and the fatty acid composition of those was mainly C16:0, C18:2n6 and C18:3n3, with less proportion for C18:1n9. The free-radical scavenging activity of the Mulato II was lower than that of the Verano stylo. The free-radical scavenging activity of the Mulato II was lower than that of the Verano stylo. For LD muscle, the fatty acid composition was mainly C16:0, C18:0 and C18:1n9, with less proportion for C18:2n6. The LD muscle of the goats fed with Mulato II and the Verano stylo by grazing had highest free-radical scavenging activity, compared to those fed with cut-and-carry and silage regime, although there were rather high unsaturated fatty acids in LD muscle. Thus, feeding the meat goats with the Mulato II and Verano stylo by grazing would be beneficial effect for consumers to intake high unsaturated fatty acids and lower risk for oxidation from goat meat.
Abstract: The objective of this study was to investigate the effects of dietary supplementation with raw or heat-treated sunflower oil seed with two levels of 7.5% or 15% on unsaturated fatty acids in milk fat and performances of high-yielding lactating cows. Twenty early lactating Holstein cows were used in a complete randomized design. Treatments included: 1) CON, control (without sunflower oil seed). 2) LS-UT, 7.5% raw sunflower oil seed. 3) LS-HT, 7.5% heat-treated sunflower oil seed. 4) HS-UT, 15% raw sunflower oil seed. 5) HS-HT, 15% heat-treated sunflower oil seed. Experimental period lasted for 4 wk, with first 2 wk used for adaptation to the diets. Supplementation with 7.5% raw sunflower seed (LS-UT) tended to decrease milk yield, with 28.37 kg/d compared with the control (34.75 kg/d). Milk fat percentage was increased with the HS-UT treatment that obtained 3.71% compared with CON that was 3.39% and without significant different. Milk protein percent was decreased high level sunflower oil seed treatments (15%) with 3.18% whereas CON treatment is caused 3.40% protein. The cows fed added low sunflower heat-treated (LS-HT) produced milk with the highest content of total unsaturated fatty acid with 32.59 g/100g of milk fat compared with the HS-UT with 23.59 g/100g of milk fat. Content of C18 unsaturated fatty acids in milk fat increased from 21.68 g/100g of fat in the HS-UT to 22.50, 23.98, 27.39 and 30.30 g/100g of fat from the cow fed HS-HT, CON, LS-UT and LS-HT treatments, respectively. C18:2 isomers of fatty acid in milk were greater by LSHT supplementation with significant effect (P < 0.05). Total of C18 unsaturated fatty acids content was significantly higher in milk of animal fed added low heat-treated sunflower (7.5%) than those fed with high sunflower. In all, results of this study showed that diet cow's supplementation with sunflower oil seed tended to reduce milk production of lactating cows but can improve C18 UFA (Unsaturated Fatty Acid) content in milk fat. 7.5% level of sunflower oil seed that heated seemed to be the optimal source to increase UFA production.
Abstract: Environmental micro-organisms include a large number of taxa and some species that are generally considered nonpathogenic, but can represent a risk in certain conditions, especially for elderly people and immunocompromised individuals. Chemotaxonomic identification techniques are powerful tools for environmental micro-organisms, and cellular fatty acid methyl esters (FAME) content is a powerful fingerprinting identification technique. A system based on an unsupervised artificial neural network (ANN) was set up using the fatty acid profiles of standard bacterial strains, obtained by gas-chromatography, used as learning data. We analysed 45 certified strains belonging to Acinetobacter, Aeromonas, Alcaligenes, Aquaspirillum, Arthrobacter, Bacillus, Brevundimonas, Enterobacter, Flavobacterium, Micrococcus, Pseudomonas, Serratia, Shewanella and Vibrio genera. A set of 79 bacteria isolated from a drinking water line (AMGA, the major water supply system in Genoa) were used as an example for identification compared to standard MIDI method. The resulting ANN output map was found to be a very powerful tool to identify these fresh isolates.
Abstract: This experiment was performed with the purpose of
investigating effect of additional blend of probiotics Saccharomyces
cerevisiae and Lactobacillus acidophilus on plasma fatty acid profiles
particularly conjugated linoleic acid (CLA) in growing goats fed corn
silage, and selected the optimal levels of the probiotics for further study.
Twenty-four growing crossbred (Thai native x Anglo-Nubian) goats that
weighed (14.2 ± 2.3) kg, aged about 6 months, were purchased and
allocated to 4 treatments according to Randomized Complete Block
Design (RCBD) with 6 goats in each treatment. The blocks were made by
weight into heavy, medium, and light goats and each of the treatments
contained two goats from each of the blocks. In the mean time, ruminal
average pH unaffected, but the NH3-N and also plasma urea nitrogen
(p0.05) were raised, but propionic
proportion (p0.05) were reduced in
concurrent with raise of acetic proportion and resultantly C2:C3 ratio
(p>0.05). On plasma fatty acid profiles, total saturated fatty acids
(p>0.05) was increased, and contrasted with decrease of C15:0
(p0.05), and C18-C22 polyunsaturated fatty acids
(p
Abstract: Three strains of Vibrio parahaemolyticus (690, BCRC
13023 and BCRC 13025) implicated in food poisoning outbreaks in
Taiwan were subjected to acid adaptation at pH 5.5 for 90 min. The
growth behaviors of acid-adapted and non-adapted V.
parahaemolyticus in the media supplemented with various nitrogen
and carbon sources were investigated. The effects of acid adaptation
on the thermostable direct hemolysin (TDH) secretion and fatty acid
profiles of V. parahaemolyticus were also examined. Results showed
that acid-adapted and non-adapted V. parahaemolyticus 690, BCRC
13023 and BCRC 13025 grew similarly in TSB-3% NaCl and basal
media supplemented with various carbon and nitrogen sources during
incubation period. Higher TDH secretion was noted with V.
parahaemolyticus 690 among the three strains. However, acid-adapted
strains produced less amounts of TDH than non-adapted strains when
they were grown in TSB-3% NaCl. Additionally, acid adaptation
increased the ratio of SFA/USFA in cells of V. parahaemolyticus
strains.
Abstract: Endemic Artemia franciscana populations can be found throughout the American continent and also as an introduced specie in several country all over the world, such as in the Mediterranean region where Artemia franciscana was identified as an invasive specie replacing native Artemia parthenogenetica and Artemia salina. In the present study, the characterization of the new invasive Artemia franciscana reported from Sabkhet Halk El-Menzel (Tunisia) was done based on the cysts biometry, nauplii instar-I length, Adult sexual dimorphism and fatty acid profile. The mean value of the diameter of non-decapsulated and decapsulated cysts, chorion thickness and naupliar length is 235.8, 226.3, 4.75 and 426.8 μm, respectively. Sexual dimorphism for adults specimen showed that maximal distance between compound eyes, diameter for compound eyes, length of first antenna and the abdomen length compared to the total body length ratio, are the most important variables for males and females discrimination with a total contribution of 62.39 %. The analysis of fatty acid methyl esters profile of decapsulated cysts resulted in low levels of linolenic acid (LLA, C18:3n-3) and high levels of eicosapentaenoic acid (EPA, C20:5n-3) with 3.11 and 11.10 %, respectively. Low quantity of docosahexaenoic acid (DHA, 22:6n-3) was also observed with 0.17 mg.g-1 dry weight.