Fat Oxidation Research Articles

Can humans smell tastants?

Although studies have shown that olfaction may contribute to the perception of tastant, literature is scarce or circumstantial, especially in humans. This study aims to (i) explore whether humans can perceive solutions of basic prototypical tastants through orthonasal and retronasal olfaction and (ii) to examine what volatile odor compounds (VOCs) underlie this ability. Solutions of 5 basic tastants (sucrose, sodium chloride, citric acid, monosodium glutamate [MSG], quinine) dissolved in water, and 2 fatty acids (oleic and linoleic acid) dissolved in mineral oil were prepared. Triangle discrimination tests were performed (n = 41 in duplicate) to assess whether the tastant solutions can be distinguished from blanks (solvents) through ortho- and retronasal olfaction. Participants were able to distinguish all tastant solutions from blank through orthonasal olfaction. Only sucrose, sodium chloride, oleic acid, and linoleic acid were distinguished from blank by retronasal olfaction. Ethyl dichloroacetate, methylene chloride, and/or acetone were identified in the headspace of sucrose, MSG, and quinine solutions but not in the headspace of water, sodium chloride, and citric acid solutions. Fat oxidation compounds such as alcohols and aldehydes were detected in the headspace of the oleic and linoleic acid solutions but not the mineral oil. We conclude that prototypical tastant solutions can be discriminated from water and fatty acid solutions from mineral oil through orthonasal olfaction. Differences in the volatile headspace composition between blanks and tastant solutions may have facilitated the olfactory discrimination. These findings can have methodological implications for future studies assessing gustatory perception using these prototypical taste compounds.

Combination of Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53 attenuates fat accumulation and alters the metabolome and gut microbiota in mice with high-fat diet-induced obesity.

This study evaluated the effects of formulations with Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53 on adiposity, the alteration of microbiota, and the metabolome in high-fat diet-fed mice. The strains were selected based on their fat and glucose absorption inhibitory activities and potential metabolic interactions. The optimal ratio of the two strains in the probiotic formulation was determined based on their adipocyte differentiation inhibitory activities. Treatment of formulations with BEPC22 and BELP53 for 10 weeks decreased body weight gain at 6 weeks; it also decreased the food efficiency ratio, white adipose tissue volume, and adipocyte size. Moreover, it decreased the expression of the lipogenic gene Ppar-γ in the liver, while significantly increasing the expression of the fat oxidation gene Ppar-α in the white adipose tissue. Notably, treatment with a combination of the two strains significantly reduced the plasma levels of the obesity hormone leptin and altered the microbiota and metabolome. The omics data also indicated the alteration of anti-obesity microbes and metabolites such as Akkermansia and indolelactic acid, respectively. These findings suggest that treatment with a combination of BEPC22 and BELP53 exerts synergistic beneficial effects against obesity.

The influence of protein from black soldier fly larvae (Hermetia illucens) on the reproductive functions of roosters

Our research is devoted to studying the possibility of using food from the larvae of black soldier flies (Hermetia illucens) (low-fat flour) in the diets of breeding roosters of the Hisex Brown cross. The inclusion of 7.5% low-fat flour in the diet structure of the roosters of the experimental group led to an increase in the quality indicators of the sperm of breeding roosters, activated metabolic processes and antioxidant protection. By the time of full physiological maturation (25 weeks), the roosters of the experimental group had a superiority (P<0.05) over the control in live weight and testes weight by 2.80 and 4.25%. An increase in ejaculate volume was found by 7.55% (P<0.05), sperm concentration by 24.36% (P<0.05), sperm survival time of up to 139 hours, while reducing the number of morphologically abnormal germ cells. A connection has been established between the amino acid and mineral compositions of the experimental feed and rooster sperm. Bioactive substances of insect larvae are able to activate enzymes of the antioxidant defense of birds. In the blood of experimental roosters, the level of glutathione peroxidase increased by 2.51% (P<0.05), superoxide dismutase - by 8.37 (P<0.01), and the amount of reduced glutathione by 12.62% (P<0.01). A decrease in oxidized glutathione by 29.67% (P<0.01) was found. The end product of fat oxidation (malondialdehyde) decreased, relative to the control, by 16.51% (P<0.01). The conducted studies have proven the effectiveness of the experimental feed in the nutrition of breeding roosters.

Maximal fat oxidation rate across the adult lifespan of trained women

AbstractThe fat oxidation capacity is higher in young compared to elderly subjects and higher in premenopausal compared to postmenopausal women, but the influence of age on maximal fat oxidation (MFO) is not clear. Therefore, this study aimed to evaluate MFO (g/min) across the lifespan of trained adult women. In total, 36 healthy trained women were recruited into three groups: (n = 12), young (27 ± 3 years, mean ± SD) premenopausal, middle‐aged (57 ± 3 years), and older (71 ± 2 years) postmenopausal women and all had a body mass index <25 kg/m2. After an overnight fast, body composition was determined by dual‐energy X‐ray absorptiometry, and blood samples were obtained. A FATmax‐test was performed on a cycle ergometer, and MFO was calculated from the pulmonary V̇O2 and V̇CO2 measured by indirect calorimetry. The absolute MFO was significantly higher in young (0.40 ± 0.07 g/min) compared to both middle‐aged (0.33 ± 0.07 g/min) (p = 0.035) and old (0.25 ± 0.05 g/min) women (p < 0.001). Absolute MFO was higher in middle‐aged compared to old women (p = 0.018). Relative MFO (MFO/LBM, mg/min/LBM) was higher in young (8.39 ± 1.62 mg/min/LBM) compared to old (6.16 ± 1.14 mg/min/LBM) women (p = 0.004). A significant linear relationship was observed between absolute MFO and age (R2 = 0.41; p < 0.001), V̇O2max (R2 = 0.40; p < 0.001), and LBM (R2 = 0.13; p = 0.033), respectively, and between relative MFO and fat mass (R2 = 0.12; p = 0.04). In conclusion, the maximal capacity to oxidize fat is attenuated with age in trained women. Furthermore, postmenopausal middle‐aged women have higher absolute MFO compared to older women, and this implies that it is age per se and not a change in estrogen availability that leads to lower absolute MFO.

Study on simulation effect of physical and chemical characteristics of sausage by sausage model system.

The incorporation of Staphylococcus xylosus in sausage production is hypothesized to affect various physicochemical properties and flavor profiles of sausages. This study aimed to evaluate the simulation of these features in a sausage model and establish its applicability for in vitro studies. Both a control and an experimental model, inclusive of Staphylococcus xylosus, were assessed for changes in physicochemical indexes (pH and water activity, Aw) and the concentration of flavoring components (esters and aldehydes). Thiobarbituric acid reactive substances (TBARS) values were also measured to evaluate lipid oxidation. The introduction of Staphylococcus xylosus resulted in no significant changes in pH and Aw between the sausage and the model. However, there was a considerable increase in the content of volatile flavor compounds, specifically esters and aldehydes, in the experimental groups compared to the control. Additionally, the TBARS values in experimental groups were significantly lower than those in the control group at the end of the testing period. The findings indicate that Staphylococcus xylosus plays a critical role in enhancing the flavor profile of sausages through the increased synthesis of volatile compounds and inhibiting fat oxidation. The sausage model effectively simulated the physicochemical and flavor index responses, demonstrating its potential utility for further in vitro research on sausage fermentation and preservation techniques.

Effects of different thawing methods on the physicochemical properties and myofibrillar protein characteristics of Litopenaeus vannamei

Litopenaeus vannamei is a highly sought-after seafood, but its short shelf life makes it highly perishable due to microbial and chemical reactions. Freezing is a common technology used for extending the shelf life of shrimp. However, it is essential to undergo a thawing process before consuming or further processing frozen shrimp. In this study, the effects of different thawing methods, including immersion (IT), ultrasonic (UT), microwave (MT), refrigerator (RT), and air thawing (AT) on the qualitative parameters and protein denaturation of shrimp were investigated. The results showed that UT reduced fat oxidation and color degradation and was more effective than other thawing treatments like AT, IT, MT, and RT at retaining water. Based on the results of surface hydrophobicity, turbidity, particle size, and Zeta potential, UT reduced the aggregation and oxidation of myofibrillar proteins (MP) during the thawing process compared to other thawing methods. Utilizing UT also minimized the amount of harm that was done to MP secondary and tertiary structures during the thawing process. In conclusion, UT is a novel thawing technique to maintain the quality of shrimp meat quickly and effectively compared with other thawing methods, which is important for the quality of subsequent processing of frozen shrimp.

A Multifunctional Liposome for Synergistic Chemotherapy with Ferroptosis Activation of Triple-Negative Breast Cancer.

There is an urgent need to develop efficient treatments for highly invasive triple-negative breast cancer (TNBC) with a high rate of postoperative. Baicalin (BA) has shown inhibitory effects on several tumor cells and could activate ferroptosis in some tumor cells by producing reactive oxygen species (ROS). For overcoming the shortcomings of BA in clinical applications and enhancing the effect of ferroptosis in TNBC, herein, a multifunctional liposome (BA-Fe(III) coordination-polymer-loaded liposome, BA-Fe(III) Lipo) was developed for synergistic chemotherapy of TNBC with ferroptosis activation. Fe(III) released from BA-Fe(III) Lipo could be efficiently reduced to Fe(II) in the presence of high glutathione in tumor microenvironment, which in turn catalyzed the oxidation of unsaturated fats through lipid peroxidation for more ROS production. In addition, BA-Fe(III) Lipo activated tumor cell ferroptosis by down-regulating the enzymatic activity of ferritin heavy chain 1 protein and glutathione peroxidase. This study provided a novel therapeutic strategy for the treatment of TNBC by ingeniously combining chemotherapy with the activation of ferroptosis, which presented potential clinical applications.

A Novel Acetone Sensor for Body Fluids.

Ketones are well-known biomarkers of fat oxidation produced in the liver as a result of lipolysis. These biomarkers include acetoacetic acid and β-hydroxybutyric acid in the blood/urine and acetone in our breath and skin. Monitoring ketone production in the body is essential for people who use caloric intake deficit to reduce body weight or use ketogenic diets for wellness or therapeutic treatments. Current methods to monitor ketones include urine dipsticks, capillary blood monitors, and breath analyzers. However, these existing methods have certain disadvantages that preclude them from being used more widely. In this work, we introduce a novel acetone sensor device that can detect acetone levels in breath and overcome the drawbacks of existing sensing approaches. The critical element of the device is a robust sensor with the capability to measure acetone using a complementary metal oxide semiconductor (CMOS) chip and convenient data analysis from a red, green, and blue deconvolution imaging approach. The acetone sensor device demonstrated sensitivity of detection in the micromolar-concentration range, selectivity for detection of acetone in breath, and a lifetime stability of at least one month. The sensor device utility was probed with real tests on breath samples using an established blood ketone reference method.

Immediate Effects of Aerobic Exercise and Whole-Body Vibration on Fat Oxidation, Lipid Mobilization, and Cardiovascular Response in Individuals with Obesity.

Among obesity, cumulative fat and poor physical activity are risk factors for cardiovascular disease. Due to the limit in performing aerobic exercise (AER), whole-body vibration (WBV) as a passive form of exercise is an alternative therapeutic strategy. Herein, this study aimed to compare the immediate effects of AER and WBV on metabolic and cardiovascular responses, and dyspnea level in obesity. Forty-nine eligible obesities performed both AER and WBV, with a random order assignment (age = 28.94 ± 11.39 years). Fat oxidation, cardiovascular parameters (i.e., heart rate (HR) and blood pressure (BP)), and dyspnea level (i.e., rating perceived exertion (RPE)) were measured during exercise, while lipid mobilization (i.e., triglycerides) was collected pre- and post-exercise. Fat oxidation rate in AER was significantly higher than in WBV. Significantly increased fat oxidation rates were shown in both groups (within-group analyses) (also shown in females aged 20-45). Triglyceride levels between AER and WBV were similar. A significant decrease in triglyceride levels was only observed in WBV (within-group change). HR and RPE in AER were significantly higher than in WBV (p < 0.05). HR and RPE were significantly increased throughout both AER and WBV, while systolic blood pressure was only significantly elevated in AER (whining-group analyses). WBV may facilitate fat oxidation (particularly in females aged below 45), induce lipid mobilization, and reduce interference on cardiovascular parameters in obesity.

Low Carbohydrate, High Fat Diet Alters the Oral Microbiome without Negating the Nitrite Response to Beetroot Juice Supplementation.

A low carbohydrate, high fat (LCHF) diet in athletes increases fat oxidation but impairs sports performance, potentially due to impaired exercise economy. Dietary nitrate supplementation can improve exercise economy via an increase in nitric oxide production, which is initiated by the reduction of nitrate to nitrite within the oral cavity. This reaction is dependent on the presence of nitrate-reducing oral bacteria, which can potentially be altered by dietary changes, including a LCHF diet. This study explored the effect of a LCHF diet on the oral microbiome and subsequent changes to plasma nitrite concentration following nitrate supplementation. Following five days of LCHF or high carbohydrate (HCHO) control dietary intervention, highly trained male race walkers consumed 140 mL beetroot juice containing 8.4 mmol nitrate; they then provided (a) blood samples for plasma nitrate and nitrite analysis and (b) saliva samples for 16S rRNA sequencing of the oral microbiome. The LCHF diet (n = 13) reduced oral bacterial diversity and changed the relative abundance of the genera Neisseria (+10%), Fusobacteria (+3%), Prevotella (-9%), and Veillonella (-4%), with no significant changes observed following the HCHO diet (n = 11). Following beetroot juice ingestion, plasma nitrite concentrations were higher for the LCHF diet compared to the HCHO diet (p = 0.04). However, the absence of an interaction with the trial (pre-post) (p = 0.71) suggests that this difference was not due to the dietary intervention. In summary, we found an increase in plasma nitrate and nitrite concentrations in response to nitrate supplementation independent of diet. This suggests the oral microbiome is adaptive to dietary changes and can maintain a nitrate reduction capacity despite a decrease in bacterial diversity following the LCHF diet.

Assessing the Validity of Bulletproof Coffee’s Claims

‘Bulletproof Coffee’, a popular beverage composed of coffee, grass-fed butter, and medium-chain triglyceride oil, has gained significant attention for its purported benefits including cognitive enhancement, increased alertness and energy, appetite suppression, and improved metabolic outcomes. However, the scientific evidence supporting these claims remains limited. This review aims to evaluate the evidence and determine the validity of claims regarding Bulletproof Coffee. Studies published between 2010–2023 were retrieved and evidence pertaining to cognition, alertness and energy, hunger and satiety, serum cholesterol, and gastrointestinal tolerance and Bulletproof Coffee were evaluated. The findings suggest that the current evidence base is small, and overall, there is weak or insufficient evidence to support the claimed benefits of Bulletproof Coffee. In particular, there were no significant improvements in cognition, alertness, or energy levels from Bulletproof Coffee compared to regular coffee. The impact on hunger, satiety, resting energy expenditure, and fat oxidation appeared equivocal, with effects offset by the additional calorie intake of Bulletproof Coffee. Further research with more rigorous study designs, larger sample sizes, diverse populations, and standardized methodologies are required in addition to an examination of potential health risks associated with regular Bulletproof Coffee consumption.

Fat oxidation rates and cardiorespiratory responses during exercise in different subject populations with post-acute sequelae of SARS-CoV-2 infection: a comparison with normative percentile values.

Introduction: Post-acute sequelae of SARS-CoV-2 infection (PASC) presents a spectrum of symptoms following acute COVID-19, with exercise intolerance being a prevalent manifestation likely linked to disrupted oxygen metabolism and mitochondrial function. This study aims to assess maximal fat oxidation (MFO) and exercise intensity at MFO (FATmax) in distinct PASC subject groups and compare these findings with normative data. Methods: Eight male subjects with PASC were involved in this study. The participants were divided into two groups: "endurance-trained" subjects ( > 55mL/min/kg) and "recreationally active" subjects ( < 55mL/min/kg). Each subject performed a graded exercise test until maximal oxygen consumption () to measure fat oxidation. Subsequently, MFO was assessed, and FATmax was calculated as the ratio between at MFO and max. Results: The MFO and FATmax of "endurance-trained" subjects were 0.85, 0.89, 0.71, and 0.42 and 68%, 69%, 64%, and 53%, respectively. Three out of four subjects showed both MFO and FATmax values placed over the 80th percentile of normative data. The MFO and FATmax of "recreationally active" subjects were 0.34, 0.27, 0.35, and 0.38 and 47%, 39%, 43%, and 41%, respectively. All MFO and FATmax values of those subjects placed below the 20th percentile or between the 20th and 40th percentile. Discussion: Significant differences in MFO and FATmax values between 'endurance-trained' and "recreationally active" subjects suggest that specific endurance training, rather than simply an active lifestyle, may provide protective effects against alterations in mitochondrial function during exercise in subjects with PASC.

Exploring the potential of chewing gums containing plant extracts (clove, saffron, and clove-mint) as a natural solution for controlling obesity and associated health issues

Background:Obesity is a global health concern resulting from an excessive accumulation of fat in the body, affecting individuals of all ages, including children. Modern lifestyles and the consumption of high-calorie foods have resulted in an increase in obesity prevalence. Cardiovascular disease, diabetes, blood pressure, and certain cancers are all serious health problems that obesity can lead to.Objectives: Medicinal properties in functional foods are gaining popularity in the food industry for controlling or inhibiting diseases. Given the growing concerns about obesity and its associated health risks, the need for natural compounds with controlling or inhibiting properties is paramount. This study aimed to explore natural plant extracts for their functional properties, particularly their ability to control obesity by inhibiting lipase enzyme. To transport these biological compounds, chewing gums containing extracts of cloves (at concentrations of 0.1%, 1%, and 3%), saffron, and mint were developed. Chewing gums containing extracts can become a popular natural remedy for a variety of health problems, including obesity. Using an effective delivery system, this solution is widely available to those looking for natural alternatives to address their health concerns.Methods: The research centered on exploring the properties of natural plant extracts, which included their potential to inhibit enzymes linked to obesity and related diseases, their antioxidant properties to counteract the harmful effects of body fat oxidation, and their antibacterial properties. In addition, the research involved a sensory evaluation of chewing gum that contained these extracts.Results: Clove extract had the highest amounts of total phenolic compounds. Also, clove extract exhibited the highest antioxidant properties and Helicobacter pylori inhibition (88.05% and 25.69% at ratio of 0.7% respectively), which is thought to be associated with its high content of eugenol and other phenolic compounds. Furthermore, the extracts were evaluated for other functional properties, including their ability to inhibit pancreatic lipase, angiotensin converting enzyme (ACE), and microbial activities against Streptococcus faecalis and Candida albicans. Among extracts, saffron extract showed the highest lipase inhibitory properties (40.07, and 36.06% at concentrations of 0.7% and 0.5% respectively). Also, clove and mint showed pancreatic lipase inhibition about 31.50% and 29.24 % at concentration of 0.7 and 0.5% respectively, revealing that all extracts can be a good candidate to be used as effective additives in preventing and controlling obesity. Also, clove, mint, and saffron extracts could inhibit blood pressure enzymes (25.54, 20.70, and 19.61 respectively), which can help maintain healthy blood pressure levels. Furthermore, release kinetics of extracts from chewing gums were obtained, and shown that after 20 min the release of extracts were 73.24, 64.34, and 63.2 for saffron, mint, and clove (1%) respectively.Conclusions: Extracts were found in our research to have a beneficial effect on controlling obesity. These compounds may be effective in preventing obesity, based on their observed inhibition of pancreatic lipase enzyme. However, further research is necessary to fully comprehend the efficacy of these substances for this purpose. The significant antioxidant properties of clove may have a promising impact on reducing free radicals, which can help prevent fat oxidation in the bodies of individuals with obesity. The inhibition of ACE enzyme by extracts could potentially have a positive impact on controlling blood pressure. The extracts showed potent antimicrobial properties that can potentially alleviate mouth and throat issues associated with Streptococcus bacteria. Moreover, extracts demonstrated efficacy in reducing the presence of H. pylori, which is the causative agent of stomach infections. Also, it was shown that chewing gum can be a convenient and easily accessible means of delivering natural compounds and may be a desirable option for individuals seeking natural alternatives for managing their health concerns.Keywords: Chewing gum, Plant extracts, Obesity, Blood pressure, H. pylori infections

Exploring the potential of chewing gums containing plant extracts (clove, saffron, and clove-mint) as a natural solution for controlling obesity and associated health issues

Background:Obesity is a global health concern resulting from an excessive accumulation of fat in the body, affecting individuals of all ages, including children. Modern lifestyles and the consumption of high-calorie foods have resulted in an increase in obesity prevalence. Cardiovascular disease, diabetes, blood pressure, and certain cancers are all serious health problems that obesity can lead to.Objectives: Medicinal properties in functional foods are gaining popularity in the food industry for controlling or inhibiting diseases. Given the growing concerns about obesity and its associated health risks, the need for natural compounds with controlling or inhibiting properties is paramount. This study aimed to explore natural plant extracts for their functional properties, particularly their ability to control obesity by inhibiting lipase enzyme. To transport these biological compounds, chewing gums containing extracts of cloves (at concentrations of 0.1%, 1%, and 3%), saffron, and mint were developed. Chewing gums containing extracts can become a popular natural remedy for a variety of health problems, including obesity. Using an effective delivery system, this solution is widely available to those looking for natural alternatives to address their health concerns.Methods: The research centered on exploring the properties of natural plant extracts, which included their potential to inhibit enzymes linked to obesity and related diseases, their antioxidant properties to counteract the harmful effects of body fat oxidation, and their antibacterial properties. In addition, the research involved a sensory evaluation of chewing gum that contained these extracts.Results: Clove extract had the highest amounts of total phenolic compounds. Also, clove extract exhibited the highest antioxidant properties and Helicobacter pylori inhibition (88.05% and 25.69% at ratio of 0.7% respectively), which is thought to be associated with its high content of eugenol and other phenolic compounds. Furthermore, the extracts were evaluated for other functional properties, including their ability to inhibit pancreatic lipase, angiotensin converting enzyme (ACE), and microbial activities against Streptococcus faecalis and Candida albicans. Among extracts, saffron extract showed the highest lipase inhibitory properties (40.07, and 36.06% at concentrations of 0.7% and 0.5% respectively). Also, clove and mint showed pancreatic lipase inhibition about 31.50% and 29.24 % at concentration of 0.7 and 0.5% respectively, revealing that all extracts can be a good candidate to be used as effective additives in preventing and controlling obesity. Also, clove, mint, and saffron extracts could inhibit blood pressure enzymes (25.54, 20.70, and 19.61 respectively), which can help maintain healthy blood pressure levels. Furthermore, release kinetics of extracts from chewing gums were obtained, and shown that after 20 min the release of extracts were 73.24, 64.34, and 63.2 for saffron, mint, and clove (1%) respectively.Conclusions: Extracts were found in our research to have a beneficial effect on controlling obesity. These compounds may be effective in preventing obesity, based on their observed inhibition of pancreatic lipase enzyme. However, further research is necessary to fully comprehend the efficacy of these substances for this purpose. The significant antioxidant properties of clove may have a promising impact on reducing free radicals, which can help prevent fat oxidation in the bodies of individuals with obesity. The inhibition of ACE enzyme by extracts could potentially have a positive impact on controlling blood pressure. The extracts showed potent antimicrobial properties that can potentially alleviate mouth and throat issues associated with Streptococcus bacteria. Moreover, extracts demonstrated efficacy in reducing the presence of H. pylori, which is the causative agent of stomach infections. Also, it was shown that chewing gum can be a convenient and easily accessible means of delivering natural compounds and may be a desirable option for individuals seeking natural alternatives for managing their health concerns.Keywords: Chewing gum, Plant extracts, Obesity, Blood pressure, H. pylori infections

Preparation and characterization of zein/gelatin electrospun film loaded with ε-polylysine and gallic acid as tuna packaging system.

Composite nanofiber films loaded with ε-polylysine (PL) and gallic acid (GA) were prepared using a zein/gelatin (ZG) electrospinning method to develop effective active packaging films for tuna preservation. The morphology, structure, thermal stability, hydrophobicity, antibacterial, and antioxidant properties of the films, and their application for tuna during a period of storage of 4 °C were investigated. PL reduced the average diameter of ZG fibers, whereas GA increased it. The PL/GA/ZG film possessed a well distributed fiber morphology with an average diameter of 810 ± 150 nm. Fourier-transform infrared spectroscopy and X-ray diffraction results showed the physical loading of PL and GA in ZG film with the main chemical bonds and crystal structure unchanged. The addition of both PL and GA reduced hydrophobicity of the ZG film while the PL/GA/ZG film was still hydrophobic. GA enhanced its thermal stability and contributed to its antioxidant activity. PLand GA synergetically enhanced the antibacterial activity of ZG film against Shewanella putrefaciens. PL combined with GA is more suitable for modifying ZG film than GA alone. The PL/GA/ZG film effectively inhibited total viable counts, total volatile base nitrogen, fat oxidation, and texture deterioration of tuna fillets at 4 °C storage, and could extend the shelf life by 3 days. The PL/GA/ZG nanofiber film demonstrated promising potential for application in the preservation of aquatic products as a new antibacterial and antioxidant food packaging. © 2023 Society of Chemical Industry.

Effects of hydroxyl radicals oxidation on digestion properties of silver carp myofibrillar protein gel

The generation of hydroxyl radicals from fat oxidation during frozen storage of surimi has been confirmed to induce oxidative cross-linking of proteins, but the further effect on their digestive properties and nutritional qualities is still unclear. In this work, a simulated system composed of the silver carp myofibrillar protein (MP) and Fenton system was used to study their digestive process and activities. Affected by oxidative cross-linking, oxidized MP gels were slowly and incompletely hydrolyzed by gastrointestinal process according to free amino content, particle size and peptide amount. However, the essential amino acid proportion, reduced power and hydroxyl radical chelation of digestion products from slight oxidation group (0.1–0.5 mM H2O2) were found to be generally stronger than over-oxidation group (5.0–10.0 mM H2O2). Furthermore, the in vitro biological evaluations confirmed that there were certain antioxidant activities of digestion products without potential cytotoxicity on HepG2 cells. Oxidation treatment on MP was found to negatively maintain SOD activity and generating GSH. Nevertheless, the slight oxidation group showed great protection effects to keep HepG2 cells from cell membrane damage and release LDH. In conclusion, the slight oxidation of MP is beneficial to improve the nutritional quality and in vitro antioxidant activity of its digested products.

Improved walking energy efficiency might persist in presence of simulated full weight regain after multidisciplinary weight loss in adolescents with obesity: the POWELL study.

Weight loss leads to a reduction of the energy cost of walking but the respective implications of the metabolic and mechanic changes remain unknown. The present study compares the post-weight loss energy cost of walking (Cw) with and without a total reload of the induced weight reduction in adolescents with obesity. Energy cost of walking and substrate use were evaluated during a graded walking exercise (4×6-min at 0.75, 1, 1.25, 1.5 m.s-1) before (V1) and after a 12-week intervention in 21 adolescents with obesity (11 girls; 13.8 ± 1.4 y). After weight loss, the walking exercise was randomly repeated once without weight reload (V2) and once with a loading corresponding to the total induced weight loss during the program (V2L). Body composition was assessed before and after the intervention. Body weight and fat mass decreased in response to the 12-week intervention (p < 0.001), while FFM did not change. The absolute gross Cw (ml.m-1) was higher on V1 compared with V2 at every speed. The absolute net Cw (ml.m-1) was higher on V1 compared to V2L at 0.75 m.s-1 (p = 0.04) and 1 m.s-1 (p = 0.02) and higher on V2L compared with V2 at 1.5 m.s-1 (p = 0.03). Net Cw (ml.m-1.kg-1) on V1 being higher than V2 (p < 0.001), and V2L higher than V2 (p = 0.006). The absolute CHO oxidation (mg.min-1) did not show any condition effect (p = 0.12) while fat utilization was higher on V1 compared to V2 and V2L (p < 0.001). Relative to body weight CHO oxidation was lower on V1 compared to V2 (p = 0.04) and V2L (p = 0.004) while relative to body weight fat oxidation was higher on V1 than V2 (p = 0.002). Adolescents with obesity might not show an entire rise back to pre-weight loss values of their metabolic cost of walking when weight gain is simulated. These new findings suggest metabolic and physiological adaptations to weight loss of the energy metabolism that remain to be clarified.

Intermittent normobaric hypoxia alters substrate partitioning and muscle oxygenation in individuals with obesity: implications for fat burning.

This single-blind, crossover study aimed to measure and evaluate the short-term metabolic responses to continuous and intermittent hypoxic patterns in individuals with obesity. Indirect calorimetry was used to quantify changes in resting metabolic rate (RMR), carbohydrate (CHOox, %CHO), and fat oxidation (FATox, %FAT) in nine individuals with obesity pre and post: 1) breathing normoxic air [normoxic sham control (NS-control)], 2) breathing continuous hypoxia (CH), or 3) breathing intermittent hypoxia (IH). A mean peripheral oxygen saturation ([Formula: see text]) of 80-85% was achieved over a total of 45 min of hypoxia. Throughout each intervention, pulmonary gas exchanges, oxygen consumption (V̇o2) carbon dioxide production (V̇co2), and deoxyhemoglobin concentration (Δ[HHb]) in the vastus lateralis were measured. Both RMR and CHOox measured pre- and postinterventions were unchanged following each treatment: NS-control, CH, or IH (all P > 0.05). Conversely, a significant increase in FATox was evident between pre- and post-IH (+44%, P = 0.048). Although the mean Δ[HHb] values significantly increased during both IH and CH (P < 0.05), the greatest zenith of Δ[HHb] was achieved in IH compared with CH (P = 0.002). Furthermore, there was a positive correlation between Δ[HHb] and the shift in FATox measured pre- and postintervention. It is suggested that during IH, the increased bouts of muscle hypoxia, revealed by elevated Δ[HHb], coupled with cyclic periods of excess posthypoxia oxygen consumption (EPHOC, inherent to the intermittent pattern) played a significant role in driving the increase in FATox post-IH.

Use of Aqueous Extract of Matcha Tea as an Antioxidant in Poultry Meat Storage

This study aimed to evaluate the effect of aqueous extract of matcha tea on the oxidation of fats, and some traits of poultry breast meat kept in cool storage. The study included six treatments: T1 control, T2 distilled water, T3 matcha tea 0.5%, T4 macha tea 1.0%, T5 macha tea 1.5% and T6 industrial antioxidant BHA. Pieces (2 × 3 cm) of the breasts were fleshed with the aforementioned solutions and stored by refrigeration, and some physiochemical, and chemical tests were conducted every 3 days. The results of GC-MS examination of the aqueous extract of matcha tea showed the presence of some active compounds in large amounts, and caffeine represented 81.78% of them. The results of pH values and water holding capacity showed a significant decrease (P ≤ 0.05) in submerged breast meat cuttings in aqueous extract of matcha tea at concentrations (0.5, 1.0, 1.5%) with a clear superiority for treatment T4 (1%) in the pH values and water holding capacity, as compared with the control sample. Treatments with aqueous extract of macha tea (T3, T4, T5) showed significant decreases (P ≤ 0.05) in the oxidation indicators, and a superiority in TBA and peroxide values were observed for treatment T4 upon all treatments except the industrial antioxidant (T6), as well as the values of free fatty acids which were decreased. Values of volatile nitrogen in the cold stored chicken breast meat showed that the values of T4 treatment were the closest to the results of the industrial antioxidant treatment.

The Effect of Adding Lemongrass Leaf Powder (Cymbopogon Citratus) to the Diet as a Natural Supplement on Some Productive Traits and Oxidation Indicators in Broiler (Ross 308)

The experiment aimed to demonstrate the effect of feeding vitamin E and lemongrass (Cymbopogon citratus) to broiler chickens on production performance and physiology. 144 chicks were obtained and randomly assigned to four treatments, each with three replications and 12 birds in each replication. First and foremost, there is no addition to the control group. The second treatment T2 included 300 mg of vitamin E per kilogram of feed; the third treatment T3 included 5 g of lemongrass powder per kilogram of feed; and the fourth treatment T4 included 10 g of lemongrass powder per kilogram of feed. The following characteristics were investigated in the experiment: broiler weight gain rate; dressing percentage without edible giblets; dressing percentage with edible giblets; relative weights of edible giblets; estimation of fat oxidation in tissues by measuring the amount of Malondialdehyde in the liver; percentage of free fatty acids (FFA); and peroxide values (P.V) found in liver tissue. When compared to the control treatment, the fourth and third treatments were significantly superior (P≤0.05) in the rate of weight gain, while the second, third, and fourth treatments excelled in dressing percentage with edible giblets and without edible giblets, and there was no significant difference in the relative weights of edible giblets.