Acid Composition
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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hsueh-Han Hsieh ◽  
Veran Weerathunga ◽  
W. Sanjaya Weerakkody ◽  
Wei-Jen Huang ◽  
François L. L. Muller ◽  
...  

AbstractRecent research has revealed that shrimp sensory quality may be affected by ocean acidification but we do not exactly know why. Here we conducted controlled pH exposure experiments on adult tiger shrimp, which were kept in 1000-L tanks continuously supplied with coastal seawater. We compared survival rate, carapace properties and flesh sensory properties and amino acid composition of shrimp exposed to pH 7.5 and pH 8.0 treatments for 28 days. Shrimp reared at pH 7.5 had a lower amino acid content (17.6% w/w) than those reared at pH 8.0 (19.5% w/w). Interestingly, the amino acids responsible for the umami taste, i.e. glutamate and aspartic acid, were present at significantly lower levels in the pH 7.5 than the pH 8.0 shrimp, and the pH 7.5 shrimp were also rated as less desirable in a blind quality test by 40 volunteer assessors. These results indicate that tiger shrimp may become less palatable in the future due to a lower production of some amino acids. Finally, tiger shrimp also had a lower survival rate over 28 days at pH 7.5 than at pH 8.0 (73% vs. 81%) suggesting that ocean acidification may affect both the quality and quantity of future shrimp resources.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6400
Author(s):  
Rodrigo Rodrigues ◽  
Denise Bilibio ◽  
Manuel S.V. Plata-Oviedo ◽  
Edimir A. Pereira ◽  
Marina L. Mitterer-Daltoé ◽  
...  

The residue from commercial propolis extraction may have significant antioxidant power in food technology. However, among the challenges for using the propolis co-product as an inhibitor of lipid oxidation (LO) in baked goods is maintaining its bioactive compounds. Therefore, this study aimed to determine the propolis co-product extracts’ capability to reduce LO in starch biscuit formulated with canola oil and stored for 45 days at 25 °C. Two co-product extracts were prepared: microencapsulated propolis co-product (MECP) (with maltodextrin) and lyophilized propolis co-product (LFCP), which were subjected to analysis of their total phenolic content and antioxidant activity (AA). Relevant antioxidant activity was observed using the methods of analysis employed. The spray-drying microencapsulation process showed an efficiency of 63%. The LO in the biscuits was determined by the thiobarbituric acid reactive substances (TBARS) test and fatty acid composition by gas chromatography analysis. Palmitic, stearic, oleic, linoelaidic, linoleic, and α-linolenic acids were found in biscuits at constant concentrations throughout the storage period. In addition, there was a reduction in malondialdehyde values with the addition of both propolis co-product extracts. Therefore, the propolis co-product extracts could be utilized as a natural antioxidant to reduce lipid oxidation in fatty starch biscuit.


Ruminants ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 127-136
Author(s):  
Felice Vizzielli ◽  
Simona Tarricone ◽  
Salvatore Claps ◽  
Giuseppe De Mastro ◽  
Marco Ragni

To evaluate the influence of linseed and oregano dietary supplementation in Jonica kids, we carried out a trial that involved 30 male Jonica kids 20 days old, divided into three groups of ten animals. Each group was ascribed to one of the following dietary treatments: (C) group control fed without any supplement; (L) group fed control feed containing 3% extruded linseed (Linum usitatissimum); and (L + O) group fed control diet with 0.6% dried oregano (Origanum vulgare) and 3% extruded linseed. The kids were slaughtered at 60 days of age; carcass and cut yields were performed. The Longissimus lumborum muscle was separated to determinate physical, chemical, and fatty acid composition. Supplementation of kids’ diet with oregano did not show effects on performances in vivo and post mortem. Extruded linseed and oregano feed made commercial cuts of kids carcasses less fat (6.75% vs. 10.92% for leg; 4.82% vs. 7.73% for loin), whereas only the extruded linseed diet made the meat fatter (20.11% vs. 19.75%) and more proteic than the commercial pellet (20.11% vs. 19.75%). The use of oregano reduces the meat oxidation compared with the only use of linseed in kids’ diet (0.298 vs. 0.645). The healthy and beneficial effect of linseed in the diet is observed in meat with the lower value of n-6/n-3 ratio (4.57 vs. 8.60) and atherogenic (0.60 vs. 0.77) and thrombogenic (1.36 vs. 1.61) indices. Linseed diet enrich kids meat with healthy fatty acids that are easier to oxidize; instead, the addition of oregano, thanks to its antioxidant properties, allows a longer conservation and a more profitable marketing.


Author(s):  
Sho Shimada ◽  
Ryosuke Nakai ◽  
Kotaro Aoki ◽  
Sakae Kudoh ◽  
Satoshi Imura ◽  
...  

This study characterized a unique cultivated representative of the genus Legionella isolated from an Antarctic lake. This psychrotolerant strain had some common properties of known Legionella species but also displayed other characteristics, such as plasticity in fatty acid composition and an enrichment of mobile genes in the genome.


2021 ◽  
Vol 22 (20) ◽  
pp. 11264
Author(s):  
Špela Gruden ◽  
Nataša Poklar Ulrih

Lactoferrins are an iron-binding glycoprotein that have important protective roles in the mammalian body through their numerous functions, which include antimicrobial, antitumor, anti-inflammatory, immunomodulatory, and antioxidant activities. Among these, their antimicrobial activity has been the most studied, although the mechanism behind antimicrobial activities remains to be elucidated. Thirty years ago, the first lactoferrin-derived peptide was isolated and showed higher antimicrobial activity than the native lactoferrin lactoferricin. Since then, numerous studies have investigated the antimicrobial potencies of lactoferrins, lactoferricins, and other lactoferrin-derived peptides to better understand their antimicrobial activities at the molecular level. This review defines the current antibacterial, antiviral, antifungal, and antiparasitic activities of lactoferrins, lactoferricins, and lactoferrin-derived peptides. The primary focus is on their different mechanisms of activity against bacteria, viruses, fungi, and parasites. The role of their structure, amino-acid composition, conformation, charge, hydrophobicity, and other factors that affect their mechanisms of antimicrobial activity are also reviewed.


Author(s):  
Matěj Satranský ◽  
Adéla Fraňková ◽  
Perla Kuchtová ◽  
Kateřina Pazderů ◽  
Ivana Capouchova

The oil content and fatty acid composition were determined in the seed of 19 poppy genotypes (both landraces and modern cultivars) grown in three-year field trials. The total oil content ranged from 34.56–44.76%. The oil content in white-seeded genotypes (40.73–44.76%) exceeded the oil content in blue-seeded genotypes (34.56–40.34%) and ocher-seeded genotypes (38.36–42.69%). Linoleic acid (71.41–74.02%), oleic acid (12.35–15.51%) and palmitic acid (8.95–10.29%) were the most abundant fatty acids in the evaluated seeds of poppy genotypes. A significant negative correlation (–0.7574**) was found between linoleic and oleic fatty acids. The sum of polyunsaturated (PUFA), monounsaturated (MUFA) and saturated (SFA) fatty acids ranged from 72.43–74.91%, 12.90–16.14% and 10.99–12.46% of the total fatty acids, respectively. Both the total oil content and the content of individual fatty acids were mainly affected by the crop year (weather conditions); however, the effect of genotype and year × genotype interaction was also significant. Due to the favourable composition of fatty acids, the evaluated poppy genotypes can be<br /> a good source of nutritionally valuable oil.  


Animals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2948
Author(s):  
Tanya Kogan ◽  
Dana Grossman Dahan ◽  
Ronit Laor ◽  
Nurit Argov-Argaman ◽  
Yoel Zeron ◽  
...  

An association between progressive motility (PM) and spermatozoa fertility competence has been suggested. However, the mechanism that underlies PM is not clear enough. We examined physiological characteristics and fatty acid composition of fresh spermatozoa with high and low PM. Additional analysis of fatty acid composition and structural characteristics was performed on spermatozoa samples with high and low progressively motile spermatozoa’s survival (PMSS), i.e., the ratio between the proportion of progressively motile spermatozoa after and before cryopreservation. Finally, a fertility field trial was conducted to examine the association between the number of PM spermatozoa within the insemination straw post thawing and conception rate. Analysis of fresh spermatozoa revealed a higher omega-6 to omega-3 ratio in ejaculates with low PM relative to those with high PM (p < 0.01). The proportion of polyunsaturated fatty acids was higher in low-PMSS fresh samples (p < 0.05) relative to their high-PMSS counterparts. Fresh samples with high-PMSS expressed a higher mitochondrial membrane potential (p < 0.05) and a higher proportion of viable cells that expressed reactive oxygen species (ROS; p < 0.05). Post-thawing evaluation revealed a reduced proportion of progressively motile sperm, with a prominent effect in samples with high PM relative to low PM, defined before freezing (p < 0.01). No differences in spermatozoa mitochondrial membrane potential or ROS level were found post-thawing. A fertility study revealed a positive correlation between the number of progressively motile spermatozoa within a standard insemination straw and conception rate (p < 0.05). Considering these, the bull PMSS is suggested to be taken into account at the time of straw preparation.


2021 ◽  
Author(s):  
Evgeny Ivanov ◽  
Dmitry Korobkov ◽  
Alexander Sidorenkov ◽  
Igor Varfolomeev ◽  
Mikhail Stukan

Abstract Nowadays acidizing became one of the most common approaches used to increase the hydrocarbons production from carbonate reservoirs. An acid solution injected under pressures below the formation fracture pressures dissolves the rock matrix and, thus, facilitates the fluid flow. However, the overall treatment efficiency is crucially dependent on the acid composition and injection scenario, since the different dissolution patterns are created depending on the effective reaction rate (i.e. acid composition and matrix mineralogy) of the reactive fluid and the fluid injection rate. At slow injection rates, when the acid is spent before penetrating deep into the rock, the face dissolution scenario is observed. On the other hand, fast injection results in uniform distribution of the acid along the treatment zone and similar uniform dissolution of the matrix. The best result from production improvement point of view is achieved when the acid creates a set of thin channels - the so-called wormholes. This optimum regime corresponds to the minimum in the pore volume to breakthrough (PVBT) dependence on injection rate (Fredd, 1998; Zhang, 2021). Where PVBT is defined as the amount of treatment fluid (measured in core pore volumes) required to be injected before the appearance of macroscopic flow channel linking the opposite faces of the core. Thus, since the optimal acid composition and the injection rate are determined by geology and lithology of the reservoir, to achieve the best effect, each treatment should be preceded by experiments on representative rock samples. In addition to that, the parameters to be optimized for a typical acidizing job also include the sequence of injected fluids and the amount of the fluid to be injected (Yudin A., 2021), which requires an extensive laboratory study. Unfortunately, the amount of the core material available is usually not sufficient for such a comprehensive laboratory analysis. Moreover, the destructive nature of acidizing experiments imposes the fundamental limitation: experiments are performed on different core samples, which makes the results less conclusive.


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