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1.
Heliyon ; 10(13): e33752, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027513

RESUMO

Today, feeding protein supply according to need in high-yielding lactating cows has become a big challenge. Protein is the most costly bulk constituent of animal diet, and the price of protein sources is increasing steadily, which is different from milk price rising. Therefore, one way for farmers to reduce feed costs is to reduce dietary protein share. Ruminants obtain their amino acids from 2 sources: amino acids from ruminally undegraded protein (RUP) and microbial protein synthesized in the rumen. A key goal in ruminant nutrition strategies, maximizing the use of rumen degradable protein (RDP), is through its efficient conversion into microbial protein. Urea is a supplement and a possible source of non-protein nitrogen (NPN) in ruminants' diets which meets bacteria's ammonia needs. Rumen ammonia sources include protein, peptides, amino acids, and other nitrogen-bearing compounds. As urea, uric acid, nitrate, and possibly nucleic acid are rapidly converted to ammonia, the ammonia reservoir indicates that the ruminal metabolism of ammonia is relatively small. Bacteria in the rumen can obtain between 40 and 95 percent of their nitrogen demand from ammonia, depending on their diet. Using NPN (non-protein nitrogen) as a reliable nitrogen source for ruminants was recognized over 100 years ago. Urea is quickly released in the rumen, its use in the diet is limited due to ammonia toxicity. So, the solution to this problem is that the product in nitrogen release rate from urea changes according to the digestion of fibers in the rumen. In the past, several slow-release products were made and evaluated. Slow-release urea (SRU) sources will also affect microbial growth and livestock performance compared to conventional plant protein sources. Acceptance of SRU sources, depending on their price compared to conventional plant protein ingredients is feasible. Studies has shown that the use of slow-release urea did not have a negative effect on digestibility, rumen parameters, milk production and livestock performance. Single-cell protein (SCP) is an emerging alternative protein source, currently being mainly studied for chicken and aquatic species.Finally, it is concluded that slow release urea can be used in feeding ruminants without any side effects.

2.
Polymers (Basel) ; 16(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38931972

RESUMO

Today, 98% of all plastics are fossil-based and non-biodegradable, and globally, only 9% are recycled. Microplastic and nanoplastic pollution is just beginning to be understood. As the global demand for sustainable alternatives to conventional plastics continues to rise, biobased and biodegradable plastics have emerged as a promising solution. This review article delves into the pivotal concept of carbon recycling as a pathway towards achieving a zero-waste future through the production and utilization of high-value bioplastics. The review comprehensively explores the current state of bioplastics (biobased and/or biodegradable materials), emphasizing the importance of carbon-neutral and circular approaches in their lifecycle. Today, bioplastics are chiefly used in low-value applications, such as packaging and single-use items. This article sheds light on value-added applications, like longer-lasting components and products, and demanding properties, for which bioplastics are increasingly being deployed. Based on the waste hierarchy paradigm-reduce, reuse, recycle-different use cases and end-of-life scenarios for materials will be described, including technological options for recycling, from mechanical to chemical methods. A special emphasis on common bioplastics-TPS, PLA, PHAs-as well as a discussion of composites, is provided. While it is acknowledged that the current plastics (waste) crisis stems largely from mismanagement, it needs to be stated that a radical solution must come from the core material side, including the intrinsic properties of the polymers and their formulations. The manner in which the cascaded use of bioplastics, labeling, legislation, recycling technologies, and consumer awareness can contribute to a zero-waste future for plastics is the core topics of this article.

3.
Heliyon ; 10(6): e27316, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38509920

RESUMO

Study objectives included the assessment of carcass fatty acid composition and meat texture characteristics of younger Holstein Friesian bulls. Three experimental groups were formed based on the weights of the 23 young bulls at slaughter: lighter, medium, and heavier. Samples were taken from the Gluteus medius (GM) and Longissimus thoracis muscles 24 h after slaughter. Fatty acid composition, Warner-Bratzler Meat Shear (WBS) measurements, as well as textural profile analysis (TPA) and sensory analysis of the muscle samples were conducted. The fatty acid composition was determined using Thin Layer Chromatography (HPTLC). Polyunsaturated fatty acids and dietary fatty acids give a neutral hypocholesterolemic effect in direct fluorescent antibody (DFA) contents, DFA/OFA (C14:0+C16:0) ratio, hardness, Warner-Bratzler Shear force and also the chews number - which is desirable - before swallowing (NCBS) the meat were significantly decreased with the increasing slaughter weight. Higher slaughter weight resulted in a larger amount of beef with a better panel tenderness score; however, the meat obtained from the LSW group was less healthy considering the fatty acid profile. Additionally, internal fat contained the highest saturated fatty acids concentrations, while subcutaneous fat contained the highest amount of monounsaturated fatty acids. Furthermore, intramuscular fat levels were highest in PUFA and PUFA/SFA ratio. As a result, this study strongly suggests that slaughter weight and anatomical location of fat samples contribute significantly to meat texture characteristics and fatty acid profiles in Holstein Friesian bulls.

5.
Appl Microbiol Biotechnol ; 108(1): 60, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38183483

RESUMO

The potential consequences for mankind could be disastrous due to global warming, which arises from an increase in the average temperature on Earth. The elevation in temperature primarily stems from the escalation in the concentration of greenhouse gases (GHG) such as CO2, CH4, and N2O within the atmosphere. Among these gases, methane (CH4) is particularly significant in driving alterations to the worldwide climate. Methanotrophic bacteria possess the distinctive ability to employ methane as both as source of carbon and energy. These bacteria show great potential as exceptional biocatalysts in advancing C1 bioconversion technology. The present review describes recent findings in methanotrophs including aerobic and anaerobic methanotroph bacteria, phenotypic characteristics, biotechnological potential, their physiology, ecology, and native multi-carbon utilizing pathways, and their molecular biology. The existing understanding of methanogenesis and methanotrophy in soil, as well as anaerobic methane oxidation and methanotrophy in temperate and extreme environments, is also covered in this discussion. New types of methanogens and communities of methanotrophic bacteria have been identified from various ecosystems and thoroughly examined for a range of biotechnological uses. Grasping the processes of methanogenesis and methanotrophy holds significant importance in the development of innovative agricultural techniques and industrial procedures that contribute to a more favorable equilibrium of GHG. This current review centers on the diversity of emerging methanogen and methanotroph species and their effects on the environment. By amalgamating advanced genetic analysis with ecological insights, this study pioneers a holistic approach to unraveling the biopotential of methanotrophs, offering unprecedented avenues for biotechnological applications. KEY POINTS: • The physiology of methanotrophic bacteria is fundamentally determined. • Native multi-carbon utilizing pathways in methanotrophic bacteria are summarized. • The genes responsible for encoding methane monooxygenase are discussed.


Assuntos
Euryarchaeota , Gases de Efeito Estufa , Ecossistema , Agricultura , Biotecnologia , Carbono , Metano
6.
Food Chem ; 438: 138011, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37984000

RESUMO

Biocomposite films were prepared by formulating talipot starch with plant mucilage derived from shoeblack leaves, okra, and seeds of basil, fenugreek, and flax, which were identified as SBM-TSF, OKM-TSF, BSM-TSF, FGM-TSF, and FXM-TSF, respectively. The plant mucilages enhanced the crosslinking of the filmogenic solutions, which increased the film's relative crystallinity. Upon topographical investigation, the biocomposite films exhibited the same compact and homogeneous structures as the native talipot starch film (NTSF), but with finer corrugations. When compared to NTSF, the addition of plant mucilage decreased the moisture content while increasing the thickness and opacity. SBM-TSF showed significantly reduced (p ≤ 0.05) solubility and water vapor permeability, indicating that increased crosslink formation in the film obstructed the water vapor passage. Among all the biocomposite films, the BSM-TSF had the greatest tensile strength, making it more resistant to stretching. Among the studied biocomposite films, SBM-TSF and BSM-TSF demonstrated improved thermal and biodegradation stability.


Assuntos
Mucilagem Vegetal , Amido , Amido/química , Mucilagem Vegetal/química , Vapor , Solubilidade , Permeabilidade , Resistência à Tração
7.
Bioengineering (Basel) ; 10(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38135973

RESUMO

Bioplastics hold significant promise in replacing conventional plastic materials, linked to various serious issues such as fossil resource consumption, microplastic formation, non-degradability, and limited end-of-life options. Among bioplastics, polyhydroxyalkanoates (PHA) emerge as an intriguing class, with poly(3-hydroxybutyrate) (P3HB) being the most utilized. The extensive application of P3HB encounters a challenge due to its high production costs, prompting the investigation of sustainable alternatives, including the utilization of waste and new production routes involving CO2 and CH4. This study provides a valuable comparison of two P3HBs synthesized through distinct routes: one via cyanobacteria (Synechocystis sp. PCC 6714) for photoautotrophic production and the other via methanotrophic bacteria (Methylocystis sp. GB 25) for chemoautotrophic growth. This research evaluates the thermal and mechanical properties, including the aging effect over 21 days, demonstrating that both P3HBs are comparable, exhibiting physical properties similar to standard P3HBs. The results highlight the promising potential of P3HBs obtained through alternative routes as biomaterials, thereby contributing to the transition toward more sustainable alternatives to fossil polymers.

8.
Polymers (Basel) ; 15(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38139947

RESUMO

Today, plastic materials are mostly made from fossil resources, and they are characterized by their long lifetime and pronounced persistence in the open environment. These attributes of plastics are one cause of the ubiquitous pollution we see in our environment. When plastics end up in the environment, most of this pollution can be attributed to a lack of infrastructure for appropriately collecting and recycling plastic waste, mainly due to mismanagement. Because of the huge production volumes of plastics, their merits of being cheap to produce and process and their recalcitrance have turned into a huge disadvantage, since plastic waste has become the end point of our linear economic usage model, and massive amounts have started to accumulate in the environment, leading to microplastics pollution and other detrimental effects. A possible solution to this is offered by "bioplastics", which are materials that are either (partly) biobased and/or degradable under defined conditions. With the rise of bioplastics in the marketplace, several standards and test protocols have been developed to assess, certify, and advertise their properties in this respect. This article summarizes and critically discusses different views on bioplastics, mainly related to the properties of biodegradability and biobased carbon content; this shall allow us to find a common ground for clearly addressing and categorizing bioplastic materials, which could become an essential building block in a circular economy. Today, bioplastics account for only 1-2% of all plastics, while technically, they could replace up to 90% of all fossil-based plastics, particularly in short-lived goods and packaging, the single most important area of use for conventional plastics. Their replacement potential not only applies to thermoplastics but also to thermosets and elastomers. Bioplastics can be recycled through different means, and they can be made from renewable sources, with (bio)degradability being an option for the mismanaged fraction and special applications with an intended end of life in nature (such as in seed coatings and bite protection for trees). Bioplastics can be used in composites and differ in their properties, similarly to conventional plastics. Clear definitions for "biobased" and "biodegradable" are needed to allow stakeholders of (bio)plastics to make fact-based decisions regarding material selection, application, and end-of-life options; the same level of clarity is needed for terms like "renewable carbon" and "bio-attributed" carbon, definitions of which are summarized and discussed in this paper.

9.
Animals (Basel) ; 13(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37444023

RESUMO

A major objective of this study is to identify factors influencing the quality of high-moisture total mixed rations (TMRs) for livestock feed and explore possible manipulations that can enhance their fermentation characteristics and stability in order to address the problem of poor aerobic stability. Therefore, the current study utilized infrared thermography (IRT) to assess the aerobic stability of water-added TMRs in the feed bunker. By manipulating the moisture content of freshly prepared TMRs at four different levels through water addition and subjecting it to storage at two consistent temperatures, significant correlations between IRT values (center temperature (CT) and maximum temperature difference (MTD)) and key parameters such as lactic acid bacteria, water-soluble carbohydrates, and TMR pH were established. The first and second principal components together accounted for 44.3% of the variation, with the first component's load influenced by IRT parameters, fermentation characteristics, and air exposure times, while the second component's load was influenced by dry matter content and lactic acid concentration. The results of these studies indicate the possibility that feeding methods can be optimized by identifying portions with higher CT or MTD data using IRT measurements just before feeding dairy cows in the field. As a result, increasing the use of IRT in feed management and preservation processes is projected to have a positive impact on animal productivity in the future.

10.
Front Bioeng Biotechnol ; 11: 1137749, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404685

RESUMO

P3HB (poly-ß-hydroxybutyrate), an energy-storage compound of several microorganisms, can be used as bioplastics material. P3HB is completely biodegradable under aerobic and aerobic conditions, also in the marine environment. The intracellular agglomeration of P3HB was examined employing a methanotrophic consortium. Supplanting fossil, non-degradable polymers by P3HB can significantly reduce the environmental impact of plastics. Utilizing inexpensive carbon sources like CH4 (natural gas, biogas) is a fundamental methodology to make P3HB production less costly, and to avoid the use of primary agricultural products such as sugar or starch. Biomass growth in polyhydroxyalkanoates (PHA) in general and in Poly (3-hydroxybutyrate) manufacture in specific could be a foremost point, so here the authors focus on natural gas as a proper carbon source and on the selection of bioreactors to produceP3HB, and in future further PHA, from that substrate. CH4 can also be obtained from biomass, e.g., biogas, syngas methanation or power-to-gas (synthetic natural gas, SNG). Simulation software can be utilized for examination, optimizing and scale-up of the process as shown in this paper. The fermentation systems continuously stirred tank reactor (CSTR), forced-liquid vertical loop bioreactor (VTLB), forced-liquid horizontal tubular loop bioreactor (HTLB), airlift (AL) fermenter and bubble column (BC) fermenter were compared for their methane conversion, kLa value, productivity, advantages and disadvantages. Methane is compared to methanol and other feedstocks. It was discovered that under optimum processing circumstances and using Methylocystis hirsuta, the cells accumulated 51.6% cell dry mass of P3HB in the VTLB setup.

11.
Metabolites ; 13(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37367889

RESUMO

The chemical composition, in vitro total gas and CH4 production and performance of cattle fed on factory black tea waste (Camellia sinensis) (BTW), alfalfa (Medicago Sativa), sainfoin (Onobrychis sativa) and white clover (Trifolium repens) was investigated. The gas production was quantified at the 24th hour of the incubation process. BTW was found to vary from roughages in chemical composition (p < 0.05). In addition, the roughages differed in terms of nutrient composition and gas production (p < 0.05). In legume roughages, acetic acid (AA), propionic acid (PA), butyric acid (BA), and total volatile fatty acids (TVFA) values ranged from 52.36-57.00 mmol/L, 13.46-17.20 mmol/L, 9.79-12.43 mmol/L, and 79.71-89.05 mmol/L, respectively. In comparison with black tea waste, legume roughages had higher values of AA, PA, BA, and TVFA. Black tea waste contained a higher acetic acid ratio than legume roughages when compared as a percentage. There was a similar ratio of propionic acid to the rate calculated for sainfoin (Onobrychis sativa) and clover (Trifolium repens), and a similar ratio of butyric acid to the ratio determined for alfalfa (Medicago Sativa). The current study shows that the 5.7-6.3% tannin content of black tea waste can be used in ruminant rations with high-quality roughages. Due to the fact that BTW reduces methane emissions from ruminants and eliminates energy waste from them, the environment can be improved. To obtain more reliable results, further animal feeding experiments on legume roughages and BTW are required.

12.
Animals (Basel) ; 13(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36978533

RESUMO

To evaluate the effects of supplementation of feed additives in the last trimester of pregnancy on placental characteristics and offspring performance, this study was conducted with 48 estrous-synchronized Ghezel ewes that had randomly been assigned to one of the following six groups (n = 8): ad libitum feeding (AL); feed restriction (RF; 60% of ad libitum intake); feed restriction + propylene glycol (PG); feed restriction + propylene glycol + monensin sodium (MS); feed restriction + propylene glycol + rumen-protected choline chloride (RPC); feed restriction + propylene glycol + monensin sodium + rumen-protected choline chloride (PMC). Birth weight, body size, and rectal temperature of lambs were determined within 24 h of birth. The presence of lambs at 87 days of age was used as an index of survival to weaning. The outcome of this study was that the average placental weight of ewes in the AL and MS groups was the highest and lowest, respectively, among the treatment groups (p < 0.01). RPC ewes presented higher placental efficiency compared to AL, RF, and MS ewes (p < 0.05). The largest and smallest crown-to-rump lengths (CRLs) were observed in PMC and RF lambs, respectively (p < 0.01). In addition, lambs born from PMC, RPC, and PG ewes had a longer curved crown-to-rump length (CCRL) than those born from AL and RF ewes (p < 0.01). The concurrent administration of propylene glycol and rumen-protected choline chloride resulted in the highest birth weight among treatment groups (p < 0.01). Lambs born to PMC and RPC ewes had a higher survival rate and rectal temperature than those born to RF ewes (p < 0.05). It can be concluded that although dietary restriction does not have adverse effects on lambs' performance compared with ad libitum intake, the combined administration of propylene glycol and rumen-protected choline chloride in the ewes' restricted diet can improve placental characteristics and subsequently amend lambs' birth weight and body size. Therefore, the combined administration of these additives can be practiced during feed restriction.

13.
Animals (Basel) ; 12(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36552373

RESUMO

In ruminants' metabolism, a surplus of hydrogen is removed from the reduction reaction of NAD+ (nicotinamide adenine dinucleotide) by the formation of methane by methanogenic bacteria and archaea methanogens. The balance of calculations between VFA (volatile fatty acids), CO2, and CH4 indicates that acetate and butyrate play a role in methane production, while the formation of propionate maintains hydrogen and therefore reduces methane production. CH4 formation in ruminant livestock is not desired because it reduces feed efficiency and contributes to global warming. Therefore, numerous strategies have been investigated to mitigate methane production in ruminants. This review focuses on feed additives which have the capability of reducing methane emissions in ruminants. Due to the environmental importance of methane emissions, such studies are needed to make milk and meat production more sustainable. Additionally, the additives which have no adverse effects on rumen microbial population and where the reduction effects are a result of their hydrogen sink property, are the best reduction methods. Methane inhibitors have shown such a property in most cases. More work is needed to bring methane-reducing agents in ruminant diets to full market maturity, so that farmers can reap feed cost savings and simultaneously achieve environmental benefits.

14.
Polymers (Basel) ; 14(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36236144

RESUMO

In 2021, global petroleum-based plastic production reached over 400 million metric tons (Mt), and the accumulation of these non-biodegradable plastics in the environment is a worldwide concern. Polyhydroxybutyrate (PHB) offers many advantages over traditional petroleum-based plastics, being biobased, completely biodegradable, and non-toxic. However, its production and use are still challenging due to its low deformation capacity and narrow processing window. In this work, two linear-chain polyester oligomers were used as plasticizers to improve the processability and properties of PHB. Thermal analyses, XRD, and polarized optical microscopy were performed to evaluate the plasticizing effect on the PHB and the reflection on the mechanical behavior. Both oligomers acted as PHB plasticizers, with a reduction in Tg and Tm as a function of the plasticizer concentration, which can make it easier to handle the material in thermal processing and reduce the probability of thermal degradation. Plasticizer 2 proved to be the most promising between the two with an optimized condition of 20%, in which there was a decrease in elastic modulus of up to 72% and an increase in the maximum elongation of 467%.

15.
Nat Commun ; 13(1): 6209, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266340

RESUMO

To adapt to changing hemodynamic demands, regulatory mechanisms modulate actin-myosin-kinetics by calcium-dependent and -independent mechanisms. We investigate the posttranslational modification of human essential myosin light chain (ELC) and identify NIMA-related kinase 9 (NEK9) to interact with ELC. NEK9 is highly expressed in the heart and the interaction with ELC is calcium-dependent. Silencing of NEK9 results in blunting of calcium-dependent ELC-phosphorylation. CRISPR/Cas9-mediated disruption of NEK9 leads to cardiomyopathy in zebrafish. Binding to ELC is mediated via the protein kinase domain of NEK9. A causal relationship between NEK9 activity and ELC-phosphorylation is demonstrated by genetic sensitizing in-vivo. Finally, we observe significantly upregulated ELC-phosphorylation in dilated cardiomyopathy patients and provide a unique map of human ELC-phosphorylation-sites. In summary, NEK9-mediated ELC-phosphorylation is a calcium-dependent regulatory system mediating cardiac contraction and inotropy.


Assuntos
Actinas , Cadeias Leves de Miosina , Humanos , Animais , Cadeias Leves de Miosina/metabolismo , Fosforilação , Actinas/metabolismo , Peixe-Zebra/metabolismo , Cálcio/metabolismo , Quinases Relacionadas a NIMA/genética , Quinases Relacionadas a NIMA/metabolismo , Proteínas Quinases/metabolismo
16.
Animals (Basel) ; 12(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36290197

RESUMO

The Japanese quail (Coturnix japonica) is farmed for its eggs and meat across the globe. A series of experiments were conducted to evaluate the effect of the permanent or intermittent use of different levels of BC (bovine colostrum) on the egg performance and traits, carcass characteristics, blood biochemical and antioxidant status of laying Japanese quails. In this study, 200 laying quails were used for a duration of six weeks (week 24 to 30) to measure the selected parameters. Treatments included: (1) control (without BC); (2) 2% continuous BC; (3) 4% BC permanently; and (4) and (5) 2% and 4% BC intermittently (every other week), respectively. According to the results, performance, egg quality, carcass traits, biochemical indices and antioxidant status of BC-fed (continuous and intermittent mode) quails were improved compared to the control-diet-fed birds (p < 0.01). Per our observations, quails fed daily with 4% BC had the highest performance, best egg and carcass quality traits, best blood composition and best antioxidant status of serum, although the same parameters were also improved in birds fed intermittently with 4% BC. The final conclusion is that, although quails fed daily with 4% BC showed the best performance, intermittent feeding exerted comparable effects. Therefore, the intermittent-feeding approach could benefit the birds when colostrum preparation is limited due to the high cost of the related process. This approach could improve the economics of poultry breeding while reducing environmental problems, such as antibiotic resistance.

17.
Front Bioeng Biotechnol ; 10: 906704, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957636

RESUMO

Global catastrophes such as a supervolcanic eruption, asteroid impact, or nuclear winter could cause global agricultural collapse due to reduced sunlight reaching the Earth's surface. The human civilization's food production system is unprepared to respond to such events, but methane single cell protein (SCP) could be a key part of the solution. Current preparedness centers around food stockpiling, an excessively expensive solution given that an abrupt sunlight reduction scenario (ASRS) could hamper conventional agriculture for 5-10 years. Instead, it is more cost-effective to consider resilient food production techniques requiring little to no sunlight. This study analyses the potential of SCP produced from methane (natural gas and biogas) as a resilient food source for global catastrophic food shocks from ASRS. The following are quantified: global production potential of methane SCP, capital costs, material and energy requirements, ramp-up rates, and retail prices. In addition, potential bottlenecks for fast deployment are considered. While providing a more valuable, protein-rich product than its alternatives, the production capacity could be slower to ramp up. Based on 24/7 construction of facilities, 7%-11% of the global protein requirements could be fulfilled at the end of the first year. Despite significant remaining uncertainties, methane SCP shows significant potential to prevent global protein starvation during an ASRS at an affordable price-US$3-5/kg dry.

18.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35806332

RESUMO

Mutations in mitochondrial aminoacyl-tRNA synthetases (mtARSs) have been reported in patients with mitochondriopathies: most commonly encephalopathy, but also cardiomyopathy. Through a GWAS, we showed possible associations between mitochondrial valyl-tRNA synthetase (VARS2) dysregulations and non-ischemic cardiomyopathy. We aimed to investigate the possible consequences of VARS2 depletion in zebrafish and cultured HEK293A cells. Transient VARS2 loss-of-function was induced in zebrafish embryos using Morpholinos. The enzymatic activity of VARS2 was measured in VARS2-depleted cells via northern blot. Heterozygous VARS2 knockout was established in HEK293A cells using CRISPR/Cas9 technology. BN-PAGE and SDS-PAGE were used to investigate electron transport chain (ETC) complexes, and the oxygen consumption rate and extracellular acidification rate were measured using a Seahorse XFe96 Analyzer. The activation of the integrated stress response (ISR) and possible disruptions in mitochondrial fatty acid oxidation (FAO) were explored using RT-qPCR and western blot. Zebrafish embryos with transient VARS2 loss-of-function showed features of heart failure as well as indications of CNS and skeletal muscle involvements. The enzymatic activity of VARS2 was significantly reduced in VARS2-depleted cells. Heterozygous VARS2-knockout cells showed a rearrangement of ETC complexes in favor of complexes III2, III2 + IV, and supercomplexes without significant respiratory chain deficiencies. These cells also showed the enhanced activation of the ISR, as indicated by increased eIF-2α phosphorylation and a significant increase in the transcript levels of ATF4, ATF5, and DDIT3 (CHOP), as well as disruptions in FAO. The activation of the ISR and disruptions in mitochondrial FAO may underlie the adaptive changes in VARS2-depleted cells.


Assuntos
Valina-tRNA Ligase , Peixe-Zebra , Animais , Ácidos Graxos , Antígenos HLA/genética , Mitocôndrias/genética , Valina-tRNA Ligase/genética , Peixe-Zebra/genética
19.
Foods ; 12(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613371

RESUMO

This study aimed to investigate the effects of slaughter age (young vs. old), muscle type (Longissimus dorsi (LD), Gluteus medius (GM)) and fat deposits (kidney knob and channel fat, subcutaneous fat, intramuscular fat) on chemical, organoleptic, textural characteristics and fatty acid composition of Holstein Friesian bull meat. For this purpose, the carcasses of 26 Holstein Friesian bulls that had been fattened on the same private farm were assigned to two experimental groups based on their age at slaughter: a young group (YG) (average age: 17.0 ± 1.0 months old) and an old group (OG) (average age: 22.0 ± 1.0 months old). The percentage of crude protein, panel tenderness score, polyunsaturated fatty acid (PUFA) and saturated fatty acid (SFA) content, the PUFA/SFA ratio and the hypocholesterolemic fatty acid (DFA)/hypercholesterolemic fatty acid (OFA) ratio of the bull carcasses decreased significantly with increasing slaughter age. By contrast, the OFA content of the carcasses significantly increased (p < 0.05) with increasing slaughter age. Advanced slaughter age resulted in lower panel tenderness scores. Additionally, the meat of the bulls in the OG was considered to be less healthy because of the less desirable fatty acid composition and nutritional indices, such as the PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios, compared to the meat from the bulls in the YG. Furthermore, the intramuscular fat and internal fat contained high percentages of PUFA and SFA and high PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios. Interestingly, the percentage of OFA content in the internal and intramuscular fat tissues decreased with increasing slaughter age. In conclusion, this study provided evidence that slaughter age and muscle and fat type are essential sources of variations in the textural characteristics, sensory panel attributes and fatty acid profile of meat from Holstein Friesian bulls.

20.
Polymers (Basel) ; 13(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34771410

RESUMO

Talipot starch, a non-conventional starch source with a high yield (76%) from the stem pith of talipot palm (Corypha umbraculifera L.) was subjected to three different thermal treatments (dry-heat, heat-moisture and autoclave treatments) prior to phosphorylation. Upon dual modification of starch with thermal treatments and phosphorylation, the phosphorous content and degree of crosslinking significantly increased (p ≤ 0.05) and was confirmed by the increased peak intensity of P=O and P-O-C stretching vibrations compared to phosphorylated talipot starch in the FT-IR spectrum. The highest degree of crosslinking (0.00418) was observed in the autoclave pretreated phosphorylated talipot starch sample. Thermal pretreatment remarkably changed the granule morphology by creating fissures and grooves. The amylose content and relative crystallinity of all phosphorylated talipot starches significantly decreased (p ≤ 0.05) due to crosslinking by the formation of phosphodiester bonds, reducing the swelling power of dual-modified starches. Among all modified starches, dry-heat pretreated phosphorylated starch gel showed an improved light transmittance value of 28.4%, indicating reduced retrogradation tendency. Pasting and rheological properties represented that the thermal pretreated phosphorylated starch formed stronger gels that improved thermal and shear resistance. Autoclave treatment before phosphorylation of talipot starch showed the highest resistant starch content of 48.08%.

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