Top PDF Fatty acid profile of pork from a local and a commercial breed

Fatty acid profile of pork from a local and a commercial breed

Fatty acid profile of pork from a local and a commercial breed

acids in meat and fat has become an important issue from the standpoint of consumers, nutritionists, and food technol- ogists (Nuernberg et al., 2015). Fatty acid composition is in- fluenced by genetic factors, including breed differences. The most significant differences (p < 0.01) were observed in the percentage of C18 : 0, C18 : 1, C18 : 2 and C16 : 1 (p < 0.05). Gilts showed a higher (p < 0.05) percentage of C16 : 1 and a lower (p < 0.01) percentage of C20 : 0 fatty acids. Teix- eira et al. (2013), examining sex differences, found that the females showed a higher (p < 0.05) percentage of C16 : 0 and C18 : 1 fatty acids than males. Statistically, the SFAs of the LTL muscle did not differ between the two groups, but PL pork had a higher SFA content. Significant differences were observed between examined breeds in regard to stearic acid (C18 : 0) content. In barrows the level of SFA was sig- nificantly higher (p < 0.05) than in gilts. A higher concen- tration of SFA in loin fat of barrows in comparison to gilts was also found by Tuz et al. (2004); however, the results of research carried out by Teixeira et al. (2013) indicate that the SFA level in the loin of gilts was higher than the SFA level in boars. Although stearic acid is considered a neu- tral fatty acid, excessive intake of SFAs has been considered as the one out of many other factors for cancer and coro- nary heart disease (Webb and O’Neill, 2008). Regarding the SFA series, even if saturated fatty acids sensu lato are in- volved in atherogenic and thrombogenic processes, not all of them express the same behavior as regards the increase in serum cholesterol. Among the SFAs, lauric (C12 : 0), myris- tic (C14 : 0) and palmitic (C16 : 0) acids increased plasma cholesterol concentration (Ulbricht and Southgate, 1991). Furthermore, C14 : 0 was considered to have the most harm- ful cardiovascular effect on humans, the effect being almost 4 times the effect of C12 : 0 and C16 : 0 (Hegsted et al
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Chemical composition and fatty acid profile of rhea (Rhea americana) meat

Chemical composition and fatty acid profile of rhea (Rhea americana) meat

Raw Material: Male and Female Rhea americana (com- mon rhea) birds (registration at IBAMA nº 1/35/93/830-7) raised under nutritional management in confinement system from six to twelve months of age were used. During confine- ment, the birds feed on balanced commercial feed (Nutriavestruz® Crescimento from Purina) ad lib and three types of forage available in the pen. Rheas were slaughtered at the age of 12 months and average weight of 23 kg after 12-h hydric diet. The birds were grouped in lots for slaughter- ing: one lot with two birds and three lots with three birds each. Lot grouping was necessary to allow the work on the slaugh- ter day and the analysis procedure afterwards. The birds were stunned with electric shock (110 V, 1 min) with an adapted electrode placed on the neck and another on the cloaca. After stunning, the birds were weighed and hung by the feet. Next, the birds were bled, manually plucked, eviscerated and the carcass was completely washed with plenty of water and the parts were separated (thigh, drumstick, etc.) from the carcass. Intramuscular fat (IMF) samples were taken from eight rheas at random. IMF samples were taken from every rhea. Each sample was submitted to lipid extraction and derivatization in triplicate (n=24). Meat samples for IFM analysis were taken from the Gastrocnemius pars interna (inner steak), located on the bird thigh. The muscles were ground, homogenized, sepa- rated in plastic bags, labeled and freeze stored in N 2 atmo- sphere at -18 °C for later analysis.
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Milk fatty acid profile from grazing buffaloes fed a blend of soybean and linseed oils

Milk fatty acid profile from grazing buffaloes fed a blend of soybean and linseed oils

The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and m i l k FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the t r i a l (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content o f 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between L and H (P<0.19). Overall, these results indicate a pronounced improvement in the nutritional value of milk fat from grazing buffaloes fed little amounts (0.276g/day) of a blend of soybean and linseed oils.
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Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability

Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability

Besides cholesterol, fatty acids strongly influence mem- brane fluidity. With an increase in unsaturated fatty acids concentration, membrane fluidity increases because PUFA acyl chains are extremely flexible and can rapidly change conformational states. The fatty acid profile in adipose membranes from mesenteric fat of Alentejana and Barrosa˜ bovines fed silage- and concentrate-based diets showed no variations in PUFA sum and, foremost important, included none of the n-3 fatty acids, EPA (20:5n-3) and DHA (22:6n-3), well known for their impressive range of health benefits, the latter being recognized as a potent membrane fluidizer agent (Stillwell and Wassall, 2003). These results are in accordance to Wachira et al . (2002), who found residual concentration of both n-3 fatty acids in subcutaneous fat of sheep, even after the intake of feeding regimens enriched in linseed and fish oils. Dietary lipids do not directly affect the fatty acid composition of ruminant adipose tissues, as they do in non-ruminants (Sarkkinen et al ., 1994). Raising the PUFA content of ruminant tissues by PUFA feeding is rather complex due to the extensive hydrogenation of dietary unsaturated fatty acids by rumen microorganisms (Pond, 1999; Jambrenghi et al ., 2007). Nevertheless, the few changes observed for the general fatty acid profile in adipose membranes appear to reflect the dietary treatment imposed, instead of a breed-related effect. The same pattern had already been observed for the fatty acid profile in mesenteric fat, with diet determining the proportions of the major fatty acids as well as their partial sums (Costa ASH et al ., unpub- lished data). Although the sum of MUFA was kept similar across experimental groups, the 16:1 c 9 and 17:1 c 9 fatty acids were under the influence of diet, with higher concentration in concentrate-fed bulls. This is in line with previous reports stating that concentrate promotes higher expression or activity levels of delta-9 desaturase enzyme, responsible for the con- version of SFA to MUFA (Daniel et al ., 2004). Nevertheless, these differences relate to residual concentration of these fatty acids, ranging from 0.48% to 1.82% and, therefore we believe, play an irrelevant physiological role. Similarly, total SFA was affected by the diet factor, being the difference observed largely determined by stearic acid (18:0) concentration in Alentejana
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Chemical composition, microbiological properties, and fatty acid profile of Italian-type salami with pork backfat substituted by emulsified canola oil

Chemical composition, microbiological properties, and fatty acid profile of Italian-type salami with pork backfat substituted by emulsified canola oil

Chemical compositions of the Italian- type salami are shown in table 1. Except for moisture content, both fat and protein contents in the salami were according to the limits established by Brazilian legislation (IN nº 22) (BRASIL, 2000). As canola oil was added in an emulsified form, significant increases (P<0.05) in moisture contents were observed in both T1 and T2 compared with those in Control. Several studies have reported that the higher moisture content in meat products were due to decreased fat content and the presence of liquid fat in and on the surface of Italian-type salami made with emulsified canola oil (BLOUKAS et al., 1997; PELSER et al., 2007). In addition, higher moisture content reported in Italian- type salami made with emulsified canola oil could come from water added in the emulsion. UTRILLA et al. (2014) also related higher moisture content of dry- ripened venison sausages with higher proportion of olive oil throughout ripening time; although, differences were not particularly marked. In processing of dry-fermented meat sausages, a w is an important parameter once it sets water available for enzymatic and microbiological reactions. In salamis made with emulsified canola oil, BACKES et al. (2013) related a w values between 0.86
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Effect of Breed and Caponisation on the Growth Performance, Carcass Composition, and Fatty Acid Profile in the Muscles of Greenleg Partridge and Polbar Breeds

Effect of Breed and Caponisation on the Growth Performance, Carcass Composition, and Fatty Acid Profile in the Muscles of Greenleg Partridge and Polbar Breeds

The quality and chemical composition of poultry meat produced in an intensive breeding system depends largely on the genotype (Sirri et al., 2010), but also on the locomotor activity, possibility of feeding, and age at slaughter (Bogosavljević-Bošković et al., 2010). An important parameter influencing the quality of meat is the farming system (Meluzzi et al., 2009). As suggested by Bancos (2010), organic production, which can contribute to the improvement of the sensory properties of meat, is a better alternative to intensive farming. The protein content in the breast and thigh muscles of the capons and non-caponised cocks of both breeds was similar to that reported by other authors (Sirri et al., 2011). There were differences in the content of dry matter and total protein in the breast muscles, i.e. the capons of both breeds were characterised by a higher percentage content of these nutrients than the Zk cocks but did not differ in the levels of these components from the Pb cocks. A similar tendency was observed for the crude fat content in the thigh muscles, whereas higher amounts of this Table 8 – Fatty acid profile of abdominal fat samples
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Encapsulated specialty oils commercialized in São Paulo state, Brazil: evaluation of identity (fatty acid profile) and compliance of fatty acids and Vitamin E contents with nutrition labeling

Encapsulated specialty oils commercialized in São Paulo state, Brazil: evaluation of identity (fatty acid profile) and compliance of fatty acids and Vitamin E contents with nutrition labeling

Encapsulated specialty oils commercialized in São Paulo state, Brazil, were evaluated for their identity (fatty acids profile) and compliance with nutrition labeling (fatty acids and Vitamin E (alpha tocopherol) contents). Twenty one samples [flaxseed oil (6), evening primrose (5), safflower (8), borage (1), and black currant (1)] purchased from local markets or collected by the health surveillance agency were analyzed. The fatty acids and vitamin E contents were analyzed by gas chromatography with flame ionization detector and liquid chromatography with UV detector, respectively. Nine samples were adulterated (5 samples of safflower oil, 3 of flaxseed oil, and one of evening primrose). Among them, 3 flaxseed and 2 safflower oil samples were probably adulterated by the addition of soybean oil. Conjugated linoleic acid (CLA) was found in two safflower oils samples although the sale of oils with conjugated linoleic acid (CLA) is not permitted by the National Health Surveillance Agency in Brazil (ANVISA). Only two samples presented all values in compliance with nutrition labeling (one safflower oil sample and one borage oil sample). The results show that a continuous monitoring of encapsulated specialty oils commercialized in Brazil is necessary including a greater number of samples and sanitary surveillance.
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Plasma Fatty Acid Profile of Gestating Ewes Supplemented with Fishmeal

Plasma Fatty Acid Profile of Gestating Ewes Supplemented with Fishmeal

Animals and experimental treatments: Eight gestating ewes [Rideau-Arcott, 97±5 kg initial body weight, 100 days (d) of gestation] of similar nutritional and environmental background, were obtained from Ponsonby Sheep Research Station (University of Guelph, Ontario, Canada) and individually-housed in 4 by 6 foot indoor pens and randomly assigned to either a control diet (supplemented with soybean meal) or a FM- supplemented diet (2.64 kg/day as fed, comprising 0.312 kg protein-supplement, 0.441 kg mixed grain, 0.630 kg chopped hay, 1.261 kg alfalfa pellets). Ingredient composition of the diets is presented in Table 1. The nutrient requirements were based on both the body weight and gestational stage of the ewes determined by the Cornell Net Carbohydrate and Protein System for Sheep (Cornell University, Ithaca, NY). Feed was offered twice a day at 8:00 a.m. and 4:00 p.m., with orts being collected before the morning feeding. Animals were given ad libitum access to water throughout the duration of the study. The pooled samples of the experimental diets were analyzed for dry matter content by drying in an oven at 60°C for 48 h (AOAC, 1996). A subsample was ground using a Wiley Mill with a 1-mm screen (Thomas-Wiley, Philadelphia, PA) and stored at-20°C until analyzed. Samples were analyzed at a commercial laboratory (Agri-Food Laboratory,
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Yu ZOU1 , Kun MA1 , Mixia TIAN1

Yu ZOU1 , Kun MA1 , Mixia TIAN1

production of antibodies, blood cells, hormones and enzymes (Sousa  et  al., 2014). Amino acid composition of hot pepper seeds grown in the Northeast Region of China was analyzed and is given in Table 2. It was clear from the data that there were eighteen detectable amino acids in seed samples, which agreed with results reported by El-Adawy & Taha (2001). Results also showed that the main amino acids of hot pepper seeds studied were glutamic acid and aspartic acid (above 2 g/100 g), followed by histidine, phenylalanine, lysine, arginine, cysteine, leucine, tryptophan, serine, glycine, methionine, threonine and tyrosine (0.8-2 g/100 g). The contents of proline, alanine, valine and isoleucine (below 0.8 g/100 g) were the lowest, as compared to other amino acids. This result was similar to those previously reported by Embaby & Mokhtar (2011).
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Infl uence of Duroc breed inclusion into Polish Landrace maternal line on pork meat quality traits

Infl uence of Duroc breed inclusion into Polish Landrace maternal line on pork meat quality traits

The differences between results obtained in different groups may be associated with the differ- ent sets of breeds analyzed in the case of each of the mentioned researches. However, it was described in the research of Josell (2002) that genotype (presence of RN allele) may potentially play more important role than breed. In the mentioned study it was revealed that the Warner-Bratzler shear force values were found to be lower for Longissimus dorsi muscle from RN allele-positive animals (being more tender), while the same samples sensory panel evaluation indicated higher values (also meaning more tender meat) for the same muscle from RN allele-negative animals, regardless of breed (Josell 2002). Indeed, it might be concluded that not only breed, but also other genetic factors may infl uence pork meat tenderness and as a result modify the identifi ed infl uence of breed. On the other hand, in the present research, in contrast to the studies of Jeleníková et al. (2008) and Thornton et al. (1968), the highest tenderness values in the case of Duroc breed meat were not confi rmed.
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Parâmetros de qualidade de fritura por imersão em óleo de soja e os efeitos do consumo em ratos Wistar

Parâmetros de qualidade de fritura por imersão em óleo de soja e os efeitos do consumo em ratos Wistar

SILVA, Marina Maria Lelis da. M.Sc. Universidade Federal de Viçosa, May, 2008. Quality parameters of deep frying in soybean oil and the effects of consumption in Wistar rats. Adviser: Céphora Maria Sabarense. Co-advisers: Ângela Maria Campos Santana, Helena Maria Pinheiro Sant’Ana and Clóvis Andrade Neves.

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Rev. Nutr.  vol.22 número2

Rev. Nutr. vol.22 número2

of inducing carcinogenesis with 3 AOM injections (15mg/kg of weight), there were a greater number of ACF in the group treated with fish oil (18g fish oil/100g of diet) than in the group receiving a low concentration of maize oil (5g of maize oil/100g of diet) M=586.9, SD=140.5 vs MD=486.0, SD=89.5, respectively and in the group receiving a high concentration of maize oil MD=586.9, SD=140.5 vs MD=507.6, SD=120.9, respectively. However, in our study, the dietetic intervention began 12 weeks after carcinogen administration and by then, the mean number of ACF was MD=350.1, SD=61.0.
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Oliveira1 , Rodolpho Martin do Prado1 , José Luiz Moletta2

Oliveira1 , Rodolpho Martin do Prado1 , José Luiz Moletta2

The higher fat level provides more flavor to beef, increasing its palatability. However, in terms of consumer health, the increase in fat content could be harmful. On the other hand, genetic groups have a certain influence on the chemical composition and fatty acid profile of the longissimus muscle of animal finished in feedlot. The difference is related to the origin of the various genetic groups. Cattle with zebu genes have the highest levels of unsaturated fatty acids, due to characteristics in fiber composition and a higher percentage of muscle collagen. However, genetic manipulation has shown only little variation in beef composition.
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Fatty acid profile, color and lipid oxidation of organic fermented sausage during

Fatty acid profile, color and lipid oxidation of organic fermented sausage during

ABSTRACT: Organic fermented sausages typically spoil during long-term storage due to oxida- tive rancidity. The application of natural antioxidants to meat stuffing is a major practice intended to inhibit the oxidation process and color changes. This study aimed to assess the effect of two unusual starter cultures: three probiotic strains (Lactobacillus casei LOCK 0900, Lactobacillus casei LOCK 0908 and Lactobacillus paracasei LOCK 0919) and lactic acid bacteria from acid whey on model fermented sausage type products focusing on oxidative stability by measuring instrumental color (L*, a*, b* values), conjugated dienes (CD), TBARS immediately after 21 days of ripening (0) and after 90 and 180 days of refrigerated storage (4 ºC). Determination of fatty acid composition, in meat product was performed after ripening and after 180 days of storage. At the end of the storage period, the salted sausages were characterized by the same content of polyunsaturated fatty acids (PUFA) compared to cured samples. The addition of acid whey and a mixture of probiotic strains to nitrite-free sausage formulation was barely able to protect lipids against oxidation in comparison to nitrite during vacuum storage. Surprisingly, the use of acid whey has an influence on the desired red-pinkish color of organic fermented sausage after ripening and after 180 days of storage period.
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Antioxidant activity, fatty acid profile and tocopherols of Tamarindus indica L. seeds

Antioxidant activity, fatty acid profile and tocopherols of Tamarindus indica L. seeds

This study aimed to characterize Tamarindus indica L. seeds regarding its composition and to evaluate its antioxidant potential, fatty acid profile and content of tocopherols. In order to obtain the extract, the dried and crushed seeds were extracted with ethanol for 30 minutes in a 1:3 seeds: ethanol ratio under continuous stirring at room temperature. After that, the mixtures were filtered and subjected to roto-evaporation at 40 °C in order to determine, through direct weighing, the dry matter yields of the extracts. According to the results, Tamarindus indica L. seeds showed high content of total carbohydrates (71.91%) and offered relevant content and antioxidant activity of phenolic compounds. Tamarindus indica L. seeds oil presents high oxidative stability (15.83 hours) and significant total tocopherol content (57.77 mg.kg -1 ), besides
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Rodrigo Yutaka Dichoff Kasai1 , Ana Lúcia Salaro1 , Jener Alexandre Sampaio Zuanon1, Céphora Maria Sabarense1 , Mateus Moraes Tavares

Rodrigo Yutaka Dichoff Kasai1 , Ana Lúcia Salaro1 , Jener Alexandre Sampaio Zuanon1, Céphora Maria Sabarense1 , Mateus Moraes Tavares

RESUMO - Com este trabalho objetivou-se avaliar a suplementação de vitamina C durante a fase de condicionamento alimentar de alevinos de trairão. Um experimento foi estabelecido em delineamento inteiramente casualizado com sete tratamentos (0,0; 17,5; 52,5; 87,5; 122,5; 175,0 e 350,0 mg de vitamina C/kg de ração) e quatro repetições. Alevinos de trairão (2,8 ± 0,2 cm) foram distribuídos em aquários de 6 L, na densidade de 6 peixes/L. Uma ração basal foi confeccionada com 44,0% proteína bruta, e diariamente foi adicionada vitamina C e coração bovino. Após 20 dias, realizou-se biometria dos peixes para avaliação do ganho de peso e do comprimento, das taxas de sobrevivência e canibalismo e da uniformidade do comprimento final e para observações macroscópicas de sinais clínicos de deficiência ou excesso da vitamina. Após a biometria, dez peixes de cada dieta testada foram coletados para análise do perfil de ácidos graxos e este perfil foi comparado ao perfil de peixes, na mesma fase de vida, alimentados com peixes forrageiros coletados de viveiros de criação. Os dados de desempenho produtivo e perfil de ácidos graxos foram submetidos a análise de regressão polinomial e a uniformidade do comprimento final avaliada pelo teste de Bartlett. Houve diferença significativa apenas para a uniformidade em comprimento final e perfil de ácidos graxos da carcaça. A suplementação com 52,5 mg de vitamina C/kg de ração proporcionou maior uniformidade do comprimento final dos peixes. Os peixes dos viveiros de criação apresentaram menor concentração de PUFA (polyunsaturated fatty acids) e maior de ácidos graxos saturados em comparação aos peixes condicionados a aceitar dietas secas.
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The alga strain and growth conditions

The alga strain and growth conditions

Definitely, the total lipid content may vary noticeably among individual species or strains within and between taxonomic groups 7 . In recent years, species of green algae are often considered as a source of essential fatty acids that is necessary not only for improving the organism nutrition, but also for production of biodiesel 10-12 . However, this may not be because green algae naturally contain considerably more lipids than other algal taxa, but rather because many green algae are ubiquitous in diverse natural habitats, can easily be isolated, and generally grow faster than species from other taxonomic groups under laboratory conditions 13 . Among green algae, Scenedesmaceae family is one of the most popular food sources in experiments with herbivorous zooplankton 14 , and also a potential source of lipids that constitute up to 47% DW 15 , particularly PUFAs group, including oleic, linoleic, palmitic and alpha- linolenic acids 16 . Scenedesmus Meyen is a freshwater and marine genus with 433 known species worldwide 17 , of which 27 species has been reported in aquatic ecosystems of Iran 18 .
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Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability

Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability

Subcutaneous fat (g/kg leg) 41.3 49.5 45.8 50.7 6.47 0.663 0.325 0.800 Visceral fat (g/kg carcass) 62.6 61.5 53.7 77.5 6.19 0.576 0.082 0.058 Mesenteric fat (g/kg carcass) 16.2 17.7 14.7 22.7 2.03 0.396 0.028 0.121 Omental (g/kg carcass) 21.7 24.4 18.2 29.4 2.35 0.747 0.008 0.087 KKCF (g/kg carcass) 24.8 19.4 20.8 25.3 2.28 0.666 0.852 0.042 Dietary treatments: Sil = silage diet based on 30/70% of concentrate and silage, 593

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Isolation and fatty acid profile of selected microalgae strains from the Red Sea for biofuel production

Isolation and fatty acid profile of selected microalgae strains from the Red Sea for biofuel production

The total lipid content was determined gravimetrically and ranged from 20% to 25% of the biomass dry weight (Figure 3). Picochlorum sp. SBL2 registered the highest lipid content (25.28% ± 2.38%) and Nannochloris sp. SBL1 (19.69% ± 2.19%) showed the lowest content among all strains; Nannochloris sp. SBL4 and Desmochloris sp. SBL3 displayed 22.65% ± 2.21% and 23.16% ± 3.00%, respectively. The total lipid content of Nannochloris strains are in agreement with the range of values reported by Park et al. [18] for Nannochloris oculata, but lower than the values reported by Takagi et al. [19] and Chisti [3] for Nannochloris sp. The isolated strain of Picochlorum sp. showed a mean lipid content of 25%, slightly higher than the values reported by De la Vega et al. [20], who reported values between 20% to 23% of biomass dry weight. Oleaginous chlorophytes are known to accumulate significant amounts of lipids showing an average lipid content of 25% of dry weight [8]. Furthermore, culture conditions can increase the lipid content significantly in many microalgae strains since stress conditions are known to favour lipid induction.
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MATERIALS AND METHODS Chemicals

MATERIALS AND METHODS Chemicals

Gamma linolenic acid (GLA, 18:3, cis 6,9,12 octadecatrienoic acid), an important compound in n 6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 % of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7% of GLA in acylglycerols fraction when the borage oil was treated in a fixed bed reactor for 24 hours at 30ºC.
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