Addition Of Antioxidants Research Articles

Effect of Phycocyanin and Butylated Hydroxytoluene on the Oxidative Stability of Safflower Oil: A Comprehensive Kinetic Investigation

ABSTRACTSafflower includes both saturated and unsaturated fatty acids especially high levels of polyunsaturated fatty acid (PUFA). The addition of antioxidants during oil processing is one of the most effective methods. The aim of this research was to evaluate the oxidative stability of safflower oil supplemented with phycocyanin (PC) (200, 300, and 400 ppm), or butylated hydroxytoluene (BHT) (200 ppm), at 80, 90, and 100°C during the storage time. Oxidative stability of oil was measured through the assay of primary and secondary oxidation products: Peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) were evaluated, respectively. Results showed that the addition of PC at 300 and 400 ppm caused the lowest peroxide levels. In addition, the oxidation reactions of this oil followed a first‐order kinetic model for PV and TBARS. The amounts of PV and TBARS were dependent on the storage temperature; according to the Arrhenius equation, the activation energy (Ea) of the samples that contain 300 and 400 ppm PC decreased in all the tested temperatures compared to control. Results of the oxidative stability indicated that PC may have superior antioxidant properties than BHT and can potentially inhibit the oil oxidation. The sample containing 300 ppm PC demonstrated heightened efficacy in suppressing primary oxidation. Moreover, the results of sensory evaluation test showed that the 300 ppm PC sample received the highest rating for overall quality, which confirm that 300 ppm PC sample could be the best sample to decrease the oxidative stability in safflower oil.

Bioenergetic shift and proteomic signature induced by lentiviral-transduction of GFP-based biosensors

Fluorescent proteins (FPs) stand as pivotal tools extensively employed across diverse biological research endeavors in various model systems. However, long-standing concerns surround their use due to the numerous side effects associated with their expression. Recent investigations have brought to light the significance of hydrogen peroxide (H2O2) that is associated with the maturation process of green fluorescent protein (GFP) fluorophores. The structural and functional impairments associated with GFP expression are possibly linked to this amount of H2O2. In this study, we assess the impact of the GFP-based HyPer7 biosensor on cellular homeostasis and proteome changes, aiming to identify potential risks related to oxidative stress responses that potentially risks the application of such tools. Cells expressing genome-integrated HyPer7 demonstrated altered mitochondrial membrane potential (MMP), which was alleviated by the addition of antioxidants or culturing cells at physiological normoxia (5 kPa O2). Additionally, HyPer7-expressing cells also exhibited significant impairment in mitochondrial oxidative respiration, suggesting broader mitochondrial dysfunction. Through untargeted proteomics analysis, we identified 26 proteins exhibiting differential expression in HyPer7-expressing cells compared to respective control cells. Functional annotation analysis showed that the list of the delineated proteins is associated with cellular responses to stress and the regulation of antioxidant mechanisms. Our findings underscore the significance of caution and validation in ensuring a thorough comprehension of cellular responses when using fluorescent protein-based tools, thereby enhancing the reliability of the results.

Extending African walnut oil (Tetracarpidium conophorum) shelf-life by blending it with Palm, Groundnut and Avocado oils and study of their oxidative stability during accelerated storage

Oils rich in polyunsaturated fatty acids are beneficial for health. However, their high content in polyunsaturated fatty acids makes them unstable during processing which limit their application. In the food industry, hydrogenation and the addition of antioxidants are used to extend their shelf-life. However, hydrogenation leads to trans fatty acid which promote coronary heart disease, and synthetic antioxidant has been reported to be related to cardiovascular diseases, cancer etc. As solution, researchers have been looking for natural ways to preserve oils and fats by blending less stable with more stable ones or by using natural antioxidants. The objective of this study was to extend African walnut oil shelf life by blending it with palm oil, groundnut oil, avocado oil which are more stable. Palm, groundnut, African walnut and avocado oils were obtained through mechanical cold press method. Multisource edible oils were formulated using the binary model. The blends were prepared following the ratios 50:50, 60:40 and 70:30 (Palm oil/groundnut oil/avocado oil: African walnut oil). Each of the oils involved was also used at 100%. The samples were initially tested for their initial quality and stored at 65˚C for 21 days, 8 hours heating daily. Samples were withdrawn after every 7 days for analysis, by determining their peroxide, p-anisidine, TOTOX, thiobarbituric and acid values. Results showed that all the tested oil were of good quality. African walnut oil 100% was the most altered in terms of the presence of free fatty acids, primary and secondary oxidation products compared to the other oils samples and their blends. Africa walnut oil shelf life can be extended by blending it with Palm oil, Avocado oil or Groundnut oil.

Effectiveness of natural antioxidants on oxidative stability of margarines

Lipid oxidation has been identified as the main deterioration process of margarines and in which the addition of antioxidants is necessary. Consumers are increasingly demanding that natural preservatives replace chemical antioxidants in foods. The main aim of this study was to improve the oxidative stability of eight commercial margarines without antioxidants, selected by Principal Component Analysis and grouped into three clusters by the addition of six natural ground herbs: Curcuma longa, Illicium verum, Rosmarinus officinalis, Taraxacum officinale, Thymus piperella and Thymus vulgaris. A preliminary assay showed that the margarines with higher total fat and saturated fatty acids presented higher Induction Periods. When adding spices and herbs to margarines, Rosmarinus officinalis increased the oxidative stability value by 73.17% with respect to its baseline values, Curcuma longa, Thymus vulgaris and Thymus piperella between 17 and 26% and Taraxacum officinale together with Illicium verum reduced it by 19% and 34% respectively. The most effective species shown by chemical and statistical analysis were those containing a high content of highly lipophilic apolar phenolic compounds. A multiple linear regression model showed that Induction Period has a positive correlation with saturated and polyunsaturated fatty acids, ω−3 acids, the monounsaturated/polyunsaturated fatty acid ratio and the antioxidant activity of the added herbs. The oxidative stability of margarines is influenced by various factors and compounds present in their formulation, but the use of plants and spices could be an alternative to improve this emulsion

Optimization of biodiesel production from Croton Macrostachyus seed oil with calcium oxide (CaO) catalyst and Characterization: Potential assessment of seed and kernel

This study investigates the use of Croton macrostachyus (CMS), a widely available, fast-growing, non-edible plant common in Ethiopia’s secondary forests and less productive lands, as a biodiesel feedstock. The research compared oil yields from the seed and kernel, assessed the oxidation stability of the resulting biodiesel, and conducted transesterification using a novel combination of a CaO catalyst with methanol, which had not been explored in previous studies. Oil yield was obtained 40.8 % from the seed and 50.3 % from the kernel. Calcium oxide (CaO) was derived from eggshells through a calcination process and characterized using BET, SEM-EDX, and FTIR techniques to assess its suitability as a heterogeneous catalyst for biodiesel production. The Box-Behnken design (BBD) based on the response surface methodology (RSM) was used to optimize the reaction parameters, including reaction time (60–120 min), methanol to oil molar ratio (4:1 – 12:1), and catalyst concentration (1 % – 5 %), while the reaction temperature (60 °C) and stirring speed (450 rpm) were kept constant. Analysis of variance (ANOVA) showed that the coefficients of determination (R2 and R2 adj) were 99.42 % and 98.38 %, respectively, indicating a strong correlation between experimental and predicted values. The optimum conditions identified for maximum yield of CMS biodiesel (98.314 %) were a methanol to oil molar ratio of 8.44:1, a catalyst concentration of 2.78 %, and a reaction time of 108 min. The oxidation stability of the CMS biodiesel was obtained an induction time of 2.3 h but was enhanced to 16.17 h due to the addition of TBHQ antioxidant. All physiochemical properties were compared with ASTM D6751 and EN 14214 biodiesel standards, demonstrating that the biodiesel produced is suitable for internal combustion engine applications.

Lignin: An Adaptable Biodegradable Polymer Used in Different Formulation Processes.

LIG is a biopolymer found in vascular plant cell walls that is created by networks of hydroxylated and methoxylated phenylpropane that are randomly crosslinked. Plant cell walls contain LIG, a biopolymer with significant potential for usage in modern industrial and pharmaceutical applications. It is a renewable raw resource. The plant is mechanically protected by this substance, which may increase its durability. Because it has antibacterial and antioxidant qualities, LIG also shields plants from biological and chemical challenges from the outside world. Researchers have done a great deal of work to create new materials and substances based on LIG. Numerous applications, including those involving antibacterial agents, antioxidant additives, UV protection agents, hydrogel-forming molecules, nanoparticles, and solid dosage forms, have been made with this biopolymer. For this review, a consistent literature screening using the Pubmed database from 2019-2024 has been performed. The results showed that there is an increase in interest in lignin as an adaptable biomolecule. The most recent studies are focused on the biosynthesis and antimicrobial properties of lignin-derived molecules. Also, the use of lignin in conjunction with nanostructures is actively explored. Overall, lignin is a versatile molecule with multiple uses in industry and medical science.

Different responses of larval fatty acid profiles to cryopreservation in two commercially important bivalves.

Larval cryopreservation techniques have been established in Pacific oysters and Mediterranean mussels. Although initial cryopreservation protocols for both species differed slightly in Ficoll PM 70 (FIC) concentration, better post-thaw larval survivability was produced in mussels than oysters. Furthermore, the post-thaw survivability in the latter could be improved significantly by the addition of lipids and antioxidants to the cryoprotectant agent. These findings have generated a unique opportunity to investigate the cryo-functions of both endogenous and exogenous fatty acids (FAs) in bivalves as mammalian studies indicated that lipid compositions could contribute the interspecific difference in gamete and embryo cryopreservation. Our study showed that the higher survivability of post-thaw larvae in mussels (65% vs. 34% in oysters) could be attributed to their higher proportion of total polyunsaturated fatty acids (PUFAs), especially C22:6, and higher resistance of FA profiles to cryopreservation. In oysters, on the other hand, their FA profiles were very sensitive to cryopreservation, with saturated FAs and PUFAs being significantly increased (from 37 to 41%) and decreased (from 35% to ~ 32%), respectively. Although exogenous lipids could significantly improve the survivability of post-thaw oyster larvae from 34 to 51%, their supplementation did not alter the response pattern of endogenous FA profiles to cryopreservation.

Antioxidant activity of extracts of oregano and marsh cinquefoil, growing in the Altai region, in connection with their content of favonoids

Drugs based on medicinal plants have such advantages over synthetic analogues as low toxicity, better tolerability and reduced risk of addiction. Antioxidant agents in medicinal plants include substances from the flavonoid group, due to their ability to inactivate free radical processes, due to the mechanism of electron transfer between reaction components to neutralize free radicals. Among the medicinal plants of Western Siberia and the Altai Territory, oregano and marsh cinquefoil have a high content of flavonoids. The purpose of the study was to evaluate the antioxidant activity of alcohol-free extracts of oregano and marsh cinquefoil growing in the Altai region in connection with the content of flavonoids (flavonols and proanthocyanidins). To conduct the study, alcohol-free extracts of the studied plants were prepared using patented technology. The content of flavonols and proanthocyanidins was studied by arbitration techniques using spectrophotometry. The antioxidant activity of the extracts was measured using cathodic voltammetry method. The results showed that the average flavonol content in oregano extract was 866.5 μg/ml, while only traces were found in the extract of cinquefoil (60.0 μg/ ml). The average content of proanthocyanidins in the extract of cinquefoil was 4.05%, in the extract of oregano content of proanthocyanidins was 0.43%. The average coefficient of antioxidant activity for cinquefoil extract was 11.63 mmol/l×min and 3.81 mmol/l×min for oregano extract. From the results obtained, we can conclude that it is advisable to use extracts of marsh cinquefoil and oregano, growing in the Altai Territory, in the composition of biologically active antioxidant additives.

Effects of Supplementation of Different Antioxidants to Cryopreservation Extender on the Post-Thaw Quality of Rooster Semen-A Meta-Analysis.

The standardization of the semen cryopreservation technique could be an effective tool in poultry for the conservation of genetic resources. During this process, the production of reactive oxygen species increases, leading to oxidative stress that causes damage to the spermatozoa. To reduce this effect, the addition of exogenous antioxidants in the cryopreservation diluent has been reported to be effective. Multiple antioxidants such as catalase, vitamin E, cysteamine, ergothioneine, and serine have been studied in roosters. Therefore, the present investigation aims to perform a meta-analysis to determine if the use of the aforementioned antioxidants added to the cryopreservation extender produces an improvement in semen quality parameters in roosters after thawing. After collecting the data, a discriminant canonical analysis was performed to determine which of the selected semen quality traits provided the most information, with hypo-osmotic swelling test (HOST), viability, and total motility variables showing the highest discriminatory power. However, according to the descriptive statistics, catalase and serine are the antioxidants that improve a greater number of seminal quality parameters, and since catalase gives the most favorable results for most of the discriminating variables, it could be the antioxidant of choice.

Physicochemical Characterization and Thermodynamic Analysis of Avocado Oil Enhanced with Haematococcus pluvialis Extract

The consumption of fatty acids offers significant health benefits; however, they are prone to degradation by environmental factors. One method to preserve these fatty acids is the addition of synthetic antioxidants. This study focuses on the determination of peroxide and MDA formation rates at temperatures of 25 °C, 45 °C, and 65 °C. The oxidative stability of cold-pressed avocado oil was evaluated using pure astaxanthin, TBHQ, and H. pluvialis extract at concentrations of 100, 500, and 1000 ppm. Kinetic models and thermodynamic analysis were applied to determine the oxidation rate and compare the antioxidant effects of H. pluvialis extract with astaxanthin and TBHQ. The Arrhenius model was used to estimate activation energy (Ea), enthalpy, entropy, and free energy. Avocado oil with 500 ppm of H. pluvialis extract showed antioxidant effects comparable to TBHQ and pure astaxanthin. The activation energy of plain avocado oil was 40.47 kJ mol−1, while with H. pluvialis extract, it was 54.35 kJ mol−1. These findings suggest that H. pluvialis extract offers effective antioxidant properties and could serve as a natural alternative to synthetic antioxidants in food applications, despite the limitations of unprotected astaxanthin.

UV-induced reactive oxygen species and transcriptional control of 3-deoxyanthocyanidin biosynthesis in black sorghum pericarp.

Black pericarp sorghum has notable value due to the biosynthesis of 3-deoxyanthocyanidins (3-DOAs), a rare class of bioactive polyphenols valued as antioxidant food additives and as bioactive compounds with cytotoxicity to human cancer cells. A metabolic and transcriptomic study was conducted to ascertain the cellular events leading to the activation of 3-DOA biosynthesis in black sorghum pericarp. Prolonged exposure of pericarp during grain maturation to high-fluence ultraviolet (UV) light resulted in elevated levels of reactive oxygen species (ROS) and the activation of 3-DOA biosynthesis in pericarp tissues. In conjunction with 3-DOA biosynthesis was the transcriptional activation of specific family members of early and late flavonoid biosynthesis pathway genes as well as the downstream activation of defense-related pathways. Promoter analysis of genes highly correlated with 3-DOA biosynthesis in black pericarp were enriched in MYB and HHO5/ARR-B motifs. Light microscopy studies of black pericarp tissues suggest that 3-DOAs are predominantly localized in the epicarp and are associated with the cell wall. A working model of UV-induced 3-DOA biosynthesis in black pericarp is proposed that shares features of plant immunity associated with pathogen attack or mechanical wounding. The present model depicts ROS accumulation, the transcriptional activation of receptor kinases and transcription factors (TFs) including NAC, WRKY, bHLH, AP2, and C2H2 Zinc finger domain. This study identified key biosynthetic and regulatory genes of 3-DOA accumulation in black pericarp and provided a deeper understanding of the gene networks and cellular events controlling this tissue-and genotype-specific trait.

In vitro maturation of bovine oocytes: the role of ROS, oxidative stress, and the impact of natural antioxidant supplementation

According to available data in the literature, Brazil has one of the largest cattle herds in the world and is one of the leading embryo producers, with a clear predominance of embryos produced in vitro. These data influence the ongoing pursuit of optimizing the results obtained in IVEP (in vitro embryo production). In this technique, in vitro maturation (IVM) is such a crucial stage that it justifies studies involving components that, when added to the media, can lead to improved cleavage rates and blastocyst development. It is well known that oocyte quality is influenced by oxidative stress, and in this context, the inclusion of antioxidants in the IVM medium may enhance these outcomes. Thus, the present study aimed to review oocyte maturation, the impact of oxidative stress, and the addition of antioxidants, such as Moringa oleifera, to the IVM media.

When MnSiO3 meets ratiometric fluorescence: A facile, cost-effective ratiometric fluorescent platform based on oxidase-like MnSiO3 nanozyme for versatile Total Antioxidant Capacity (TAC) measurements

The level alterations of antioxidants are highly associated with various oxidative stress-related diseases, food quality and drug safety problems, which enables the reliable and accurate determination of total antioxidant capacity (TAC) become progressively significant. Herein, for the first time, we explored the catalytic effect of MnSiO3 nanozyme with oxidase-like activity towards different fluorescent substrates, and introduced ratiometric fluorescence to MnSiO3-based biosensing. By harnessing MnSiO3-propelled catalytic oxidation of two fluorescent substrates with contrary responses (Scopoletin, SC and o-phenylenediamine, OPD), we constructed a facile, cost-effective ratiometric fluorescent (RF) platform for TAC measurement. In the absence of antioxidants, SC and OPD can be oxidized, and the synergistic effect of fluorescence resonance energy transfer (FRET) and inner-filter-effect (IFE) between SC and oxidized OPD (Ox-OPD) will result in the weak fluorescence of Ox-SC at 465 nm and the strong one of Ox-OPD at 562 nm, respectively. However, the addition of antioxidants will dissociate MnSiO3, generating the recovered high/low fluorescence values of both substrates. Through monitoring the FI465/FI562 changes, the RF analysis of different antioxidants (Cys, AA, GSH) with satisfactory sensitivity is performed and the TAC measurements in diverse real samples (human serums, beverages, and drugs) are successfully accomplished. Moreover, the system demonstrates high selectivity and could compete with the commercial TAC test kits.

Optimization of torrefaction conditions on antioxidant activity of prickly pear seeds extract using response surface methodology and chemometric analysis

The prickly pear (Opuntia ficus-indica L., Cactaceae) seeds can be used as an alternative food product by the torrefaction process. Torrefaction is a pre-treatment process of biomass into solid fuel within a temperature range of 60-200°C. This study aimed to investigate the effect of torrefaction parameters on the antioxidant potential of prickly pear seeds, which is considered a food by-product, by using the Central Composite Design approach (CCD).The best torrefaction parameters found to have the optimal phytochemical contents were: 200°C and 50 min with 104.86±1.94 GAE/g extract for Total Phenolic Content (TPC), 200°C and 50 min with 81.23±0.90mg QE/g extract for Total Flavonoid Content (TFC), 200°C and 50 min with IC50=90.66±2.09 μg/ml for free radical scavenging activity (DPPH assay), 200°C and 50 min with IC50=124.9±4 μg/ml for radical cation total antioxidant capacity (ABTS assay). Our results demonstrated an increase of antioxidant activities with the increase of torrefaction parameters. Therefore, torrefaction has proven to be a value-added process to exploit prickly pear seed biomass and use it as a source of antioxidant food additives.

Comparative study of Tris Turmeric, Tris Turmeric Dimethyl Sulfoxide and Tris Turmeric Ethylene glycol extenders on the cryosurvivability, sperm resistance, in- vivo fertility and antioxidant status in buffalo bull semen

The freeze-thaw process leads to structural and functional damage due to excessive accumulation of reactive oxygen species (ROS). The addition of exogenous antioxidants to sperm diluents is of great importance to overcome oxidative damage during freezing. The purpose of this study was to explore the effects of three diluents Tris Turmeric, Tris Turmeric Dimethyl Sulfoxide and Tris Turmeric Ethylene glycol on the cold survival ability of buffalo sperm. Semen was collected from five local adult male buffalo breeds. A base diluent of Tris-citric acid-fructose (TCF) was prepared, adding 20% whole egg yolk (TCFY). The Tris extender without turmeric, without DMSO, and without EG was kept as a control. Other extenders are Tris containing turmeric TT (100 ml/5 ml Tris), Tris containing turmeric dimethyl sulfoxide TTD (100 ml/5 ml Tris + 1.5% DMSO) and Tris containing turmeric and ethylene glycol TTE EG (100 ml/5 ml Tris + 1.5% EG). Semen samples were added and a pure sperm concentration of 60 × 106/ml was achieved. Frozen buffalo sperm after thawing showed significant improvements in all research parameters of the three breeding samples compared to the control. Tris Turmeric Ethylene was the type that best improved sperm survival under frozen conditions, followed by Tris Turmeric and Tris Turmeric Dimethyl Sulfoxide compared to the control. A significant decrease in sperm motility after thawing was evident as usage time increased in all expanders. There was a significant increase in total antioxidant content (TAC) and insignificant change in malondialdehyde (MDA) of the diluent used compared to the control. Conception rate (CR) was higher in Tris Turmeric Ethylene glycol (65.2%), followed by Tris Turmeric (60.3%) and Tris Turmeric Dimethyl Sulfoxide (55.9%) compared to the control (36, 7%). It can be concluded that Tris Turmeric Ethylene Glycol is considered the best agent for improving cold survival and sperm fertility, followed by Tris Turmeric and Tris Turmeric Dimethyl Sulfoxide.

Pelatihan Pembuatan Bakso Daging Ayam Afkir dengan Penambahan Antioksidan Alami pada Ibu Rumah Tangga di Kelurahan Padaidi, Kabupaten Pinrang

housewives in the Padaidi village, Mattiro Bulu sub-district, Pinrang regency are not economically productive; they rely solely on their husbands' income. On the other hand, this area is predominantly inhabited by chicken egg farmers. Generally, laying hens are culled after 70-76 weeks and have tougher meat compared to broiler chickens, resulting in very low market value. Therefore, technological intervention is needed to increase the added value of culled chickens. One of the alternatives to address this issue is empowering housewives to develop productive businesses in the field of processing livestock products, particularly processed culled chicken meat products such as meatballs, nuggets, sausages, and other processed meat products with the addition of natural antioxidants to produce healthier and more nutritious functional food products. The implementation method included coordination, discussions, education, training, and mentoring for partners (housewives). Based on the results, participants were very enthusiastic about attending training on making meatball from culled chicken meat with the addition of moringa leaf powder as a natural antioxidant. This training activity was expected to stimulate and motivate the local community, especially housewives, to engage in productive businesses in processing livestock products to help improve nutrition and family income.

Coenzyme Q10 Improves the Post-Thaw Sperm Quality in Dwarf Surfclam Mulinia lateralis.

Previous studies have shown that post-thaw sperm performance is affected by multiple stressors during cryopreservation, such as those induced by physical, chemical, mechanical and physiological changes. One of these is the balance disturbance between the antioxidant defense system and reactive oxygen species (ROS) production. This study investigated whether this disturbance could be alleviated by the addition of different antioxidants to cryoprotective solution [8% dimethyl sulfoxide (DMSO) in 1 µm filtered seawater] optimized for the sperm in dwarf surf clam Mulinia lateralis, the model bivalve species used in many different types of studies. Results showed that the addition of 20 μM coenzyme Q10 (Q10) to 8% DMSO achieved a D-stage larval rate similar to that of the fresh control at a sperm-to-egg ratio at least 50% less than the 8% DMSO treatment alone. The addition of other antioxidants (glycine, melatonin and polyvinylpyrrolidone) did not have any positive effects. The improvement in post-thaw sperm quality by Q10 could be due to its ability to significantly decrease ROS production and lipid peroxidation and significantly increase the motility, plasma membrane integrity, mitochondrial membrane potential, acrosome integrity, DNA integrity and activities of catalase and glutatione. In this study, 37 fatty acids (FAs) were quantified in dwarf surf clam sperm, with 21 FAs being significantly impacted by the cryopreservation with 8% DMSO. Thirteen of these 21 FAs were changed due to the addition of 20 μM Q10 to 8% DMSO, with approximately half of them being improved significantly toward the levels of fresh control, while the remaining half extended further from the trends shown with 8% DMSO treatment. However, no significant difference was found in the percentage of each FA category sum and the ratio of unsaturated/saturated FAs between the two treated groups. In conclusion, the antioxidant Q10 has shown the potential to further improve the sperm cryopreservation technique in bivalves.

Systematic Engineering to Enhance β-Myrcene Production in Yeast.

β-Myrcene is an important monoterpene compound widely used in the fragrance, agricultural, and food industries. The microbial production of β-myrcene conforms to the trend of green biological manufacturing, which has great potential for development. The poor catalytic activity of β-myrcene synthase (MS) and the insufficient supply of precursors are considered to be the bottlenecks of β-myrcene production. Here, source screening, subcellular localization, enzyme fusion, and precursor-enhancing strategies were integrated for β-myrcene biosynthesis with Saccharomyces cerevisiae. The β-myrcene titer gradually increased by 218-fold (up to 63.59 mg/L) compared to that of the initial titer of the shake flask. Moreover, the titer reached 66.82 mg/L after the addition of antioxidants (1 mM glutathione, GSH, and 1% butylated hydroxytoluene, BHT). Ultimately, 142.64 mg/L β-myrcene in S. cerevisiae was achieved in 5.0 L of fed-batch fermentation under a carbon restriction strategy, which was the highest reported titer in yeast thus far. This study not only established a platform for β-myrcene production but also provided a reference for the efficient biosynthesis of other monoterpene compounds.

Potential mechanisms and modifications of dietary antioxidants on the associations between co-exposure to plastic additives and diabetes

BackgroundThe association of plastic additive mixture exposure with diabetes and the modifying effects of dietary antioxidants are unclear.MethodsThe data from the NHANES 2011–2018 were retrieved, and phthalates and organophosphate esters (OPEs) were selected as exposures. The coexposure effect was analyzed by the environmental risk score (ERS) and quantile g-computation. To mitigate any potential bias caused by using the internal weights, another version of ERS was constructed using the cross-validation approach. The level of dietary antioxidant intake was measured by the composite dietary antioxidant index (CDAI). The biological mechanism underlying the association was studied by the adverse outcome pathway (AOP) framework.ResultsFifteen chemicals (ten phthalates and five OPEs) were measured in 2824 adult participants. A higher ERS was significantly associated with an increased risk of diabetes (OR per 1-SD increment of ERS: 1.25, 95% CI: 1.13–1.39). This association apparently interacted with the CDAI level (ORlow: 1.83, 95% CI: 1.37–2.55; ORhigh: 1.28, 95% CI: 1.15–1.45; Pinteraction = 0.038). Moreover, quantile g-computation also revealed higher level of combined exposure was positively associated with diabetes (OR: 1.27, 95% CI: 1.05–2.87), and the addition of dietary antioxidants showed a null association (OR: 1.09, 95% CI: 0.85–2.34). The AOP study identified TCPP and TCEP as key chemicals that cause aberrant glucose metabolism and insulin signaling pathways and result in diabetes.ConclusionsCoexposure to phthalates and OPEs is positively associated with diabetes, where an antioxidative diet plays a modifying role. Several potential mechanisms have been proposed by AOP framework.

Pre- and Post-Thaw Addition of L-Carnitine and Pyruvate: Effect on Stallion Sperm Parameters.

The addition of antioxidants to cryopreservation media reportedly improves sperm post-thaw quality and reproductive performance after artificial insemination. Therefore, the objectives of this study were to evaluate if the addition of L-carnitine and pyruvate to freezing media, or their addition to samples after thawing, improves the post-thaw quality of equine spermatozoa. Thus, in Experiment 1, stallion semen samples were cryopreserved in: (1) EDTA-glucose-based extender with 20% egg yolk and 5% dimethylformamide (EDTA control); (2) skim milk-based extender with 20% egg yolk and 5% dimethylformamide (milk control); (3) Extender1 supplemented with 50 mM L-carnitine and 10 mM pyruvate (EDTA-carnitine-pyruvate); and (4) Extender 2 supplemented with 50 mM L-carnitine and 10 mM pyruvate (milk-carnitine-pyruvate). In Experiment 2, 50 mM L-carnitine and 10 mM pyruvate were added post-thaw to samples cryopreserved with extenders 1 and 2 (EDTA control and milk control). Sperm kinematic parameters, DNA fragmentation, membrane lipid peroxidation, acrosome status and viability were evaluated after thawing. No significant differences (p > 0.05) were observed for most of the kinematic parameters, DNA fragmentation, membrane lipid peroxidation, acrosome status and viability of spermatozoa, between the samples frozen in the presence or absence of L-carnitine and pyruvate, nor between the samples after the post-thaw addition of these components. A higher (p < 0.05) mean velocity and higher (p < 0.05) amplitude of lateral head displacement were observed in the samples frozen in the milk-based extender with the addition of L-carnitine and pyruvate after thawing. The addition of 50 mM L-carnitine and 10 mM pyruvate, either to the freezing extenders or after thawing, was not deleterious for sperm; however, it did not improve equine sperm motility, viability, acrosome and DNA integrity, nor decrease membrane lipid peroxidation after thawing.