Inosine Monophosphate Content Research Articles

Effects of Vine Tea Extract on Meat Quality, Gut Microbiota and Metabolome of Wenchang Broiler.

Simple SummaryThe current work was to assess the effect of vine tea (Ampelopsis grossedentata) extract (AGE) addition on the meat quality, gut microbiota and metabolome of Wenchang broilers. It was found that diet addition with AGE could enhance the quality and flavor of Wenchang broiler.This study investigates the effects of vine tea (Ampelopsis grossedentata) extract (AGE) on meat quality, gut microbiota and cecal content metabolites of Wenchang broilers. A total of 240 female Wenchang broilers aged 70 days were randomly allocated into four groups with five replicates of twelve broilers each. Broilers were fed a corn-soybean basal diet supplemented with AGE at 0 (T1), 0.2% (T2), 0.4% (T3) and 0.6% (T4) until 124 days of age. The whole feeding trial lasted 54 days. Results suggest that the content of total triglycerides and low-density lipoprotein cholesterol in serum of broilers are linearly reduced with dietary AGE supplementation (p < 0.05). The T3 and T4 groups had higher (p < 0.05) a* value in thigh and breast muscles than the T1 group. Additionally, the dietary supplementation of AGE decreased the shear force and drip loss of both thigh and breast muscles linearly (p < 0.05). Compared with the T1 group, AGE supplementation increased the levels of inosine monophosphate (IMP) significantly (p < 0.05) in both the thigh and breast muscles. Furthermore, an increase (p < 0.05) in the total unsaturated fatty acid (USFA), polyunsaturated fatty acids (PUFA) and the ratio of unsaturated fatty acids to saturated fatty acid (USFA: SFA) in both the thigh and breast muscles in the T3 group was observed. Higher abundance of Bacteroidota (p < 0.05) and lower abundance of Firmicutes (p < 0.05) were observed in the T3 group. The abundance of Faecalibacterium was significantly decreased (p < 0.05) in the T3 group compared with the T1 group. Cholesterol sulfate and p-cresol sulfate were identified as differential metabolites between the T1 and T3 groups. It suggested that 0.4% of AGE supplementation significantly downregulated the levels of p-cresol sulfate and cholesterol sulfate (p < 0.05) and the hepatic 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) activity compared with the control. Our present study demonstrates that dietary supplementation with AGE can improve the quality and flavor by increasing the IMP and PUFA content in the muscle of Wenchang broilers. Furthermore, dietary AGE supplementation with 0.4% can regulate the cholesterol metabolism of Wenchang broilers.

Enhancing processed quality of roasted eel with ultrasound treatment: Effect on texture, taste, and flavor

To enhance processed quality, ultrasound treatment was used in eel products processing. This study aimed to investigate the effects of ultrasonic power on the processed quality of roasted eel. Prior to toasting, eel muscle was treated with ultrasonic power from 0 W to 1000 W. Results showed that the highest water content (80.0%) was produced with 600 W ultrasound. Ultrasound above 400 W increases the hardness and chewiness of (p < .05). The SEM results illustrated the application of ultrasound promoted a more porous and homogeneous network. 600 W ultrasound can increase the umami amino acids, and enhance the content of adenosine monophosphate (p > .05) and inosine monophosphate (p < .05). Thiobarbituric acid was increased by ultrasound, especially over 600 W (p < .05). Polyunsaturated fatty acids changed greatly due to the ultrasound treatment (42.50% ~ 38.91%). Samples treated with 400 ~ 600 W had the most abundant volatile organic compounds. In conclusion, ultrasound treatment especially within 600 W enhanced the processed quality of roasted eel. Novelty impact statement This work further investigates effect of ultrasonic power on processed quality of roasted eel in ultrasonic assisted processing, including the influences on texture, taste and flavor. The application of ultrasound helped to obtain a more porous and homogeneous network. Meanwhile, ultrasound treatment can increase protein degradation and lipid oxidation, and finally promote the formation of umami contents and volatile organic compounds.

A comparative study of meat quality and vibrational spectroscopic properties of different chicken breeds

Chicken breed is one of the key factors that influence meat quality. The quality attributes of breast meat from commercial broiler (CB), Thai native chicken (NC, Leung Hang Khao), and the crossbred Korat chicken (KC) were investigated via synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy, Fourier transform Raman (FT-Raman) spectroscopy, and physicochemical analysis. The protein and carbonyl contents of KC and NC meats were higher than that of CB meat, but the lipid content was lower (P < 0.05). CB meat was characterized by high moisture, lightness (L*), and presence of taste-active nucleotides, namely, inosine 5′-monophosphate (IMP) and guanosine 5′-monophosphate (GMP). Moreover, NC meat had the highest insoluble collagen and inosine contents (P < 0.05). The predominant protein secondary structures of KC and NC meats were β-turns and random coils, whereas α-helices were mainly found in CB meat. Based on principal component analysis, the meat quality and spectra were clearly separated by breeds. The high moisture and lipid content of meat corresponded to O–H stretching (3,203 cm−1) and C–H stretching (2,854 cm−1) in the FT-Raman spectra, whereas PO2− stretching (1,240 cm−1), measured via SR-FTIR, was well correlated with the IMP content. In addition, the FT-Raman wavenumber of 934 cm−1, indicating C–C stretching, was correlated with high water-holding capacity (WHC) in KC meat. The quality of meat from slow- and fast-growing chickens significantly varies. Vibrational spectroscopy is a powerful technique that provides insightful molecular information correlated with various meat attributes.

Effects of dietary supplementation of a mixture of ferulic acid and probiotics on the fillet quality of Megalobrama amblycephala fed with oxidized oil

To investigate the effects of feed composition on the quality of fillets, Megalobrama amblycephala were fed three diets containing either soybean oil (S group) or oxidized soybean oil (OS group), and oxidized soybean oil supplemented a mixture of ferulic acid and probiotics (BS group) for 8 weeks. After the feeding trial, fish fillets were collected for determining flavor nucleotides and free amino acids (FAAs). In addition, gas chromatography-ion migration spectrometry (GC-IMS) was used to analyze the volatile components and flavor profile in the fillets. The results showed that oxidized soybean oil contributed to the accumulation of off-flavor nucleotides such as hypoxanthine (Hx), hypoxanthin riboside (HxR), and umami-related FAAs. Mixtures of ferulic acid and probiotics promoted the accumulation of umami nucleotides, such as guanosine monophosphate (GMP) and inosine monophosphate (IMP), and off-flavor FAAs. The content of GMP and IMP in BS group was significantly (P < 0.05) higher than that in S group, while Hx and HxR showed the minimum value in S group and were significantly (P < 0.05) lower than that in OS and BS group. The content of glutamic acid in OS group was significantly (P < 0.05) higher than that in the other two groups, but phenylalanine, isoleucine and leucine, three off-flavor FAAs, had the highest values in BS group and were significantly (P < 0.05) higher than that in S and BS groups. The fingerprints of GC-IMS presented that the volatile substances, such as aldehydes, ketones, and esters, were significantly different in responding to the dietary compositions. The peak expression of 2-octanol in OS group was the highest and significantly (P < 0.05) higher than that in the other two groups, while the peak expression of ethanol in S group was significantly (P < 0.05) higher than that in OS group but significantly (P < 0.05) lower than that in BS group. Both nonanal and pentanal had the highest peak expression in OS group, which was significantly (P < 0.05) higher than that in S group. 2-heptanone-D and acetone are ketones. The peak expression level of 2-heptanone-D in OS group was significantly (P < 0.05) lower than that in BS group but significantly (P < 0.05) higher than that in S group, while acetone expression level in OS group was significantly (P < 0.05) lower than that in the other two groups. The peak expression of ethyl formate as an ester in BS group was significantly lower than that in S and OS groups. In general, the fish fillet quality of M. amblycephala is affected by dietary lipids. Dietary mixture feed additive of ferulic acid and probiotics (Aspergillus oryzae and Lactobacillus plantarum) increased the contents of the flavor substances in fish meat, especially flavored nucleotides, ketones, and esters.

동물복지 사육환경이 두 육계 품종의 가슴육 및 다리육의 대사체학적 특성에 미치는 효과

This study investigates the metabolomic changes in breast and thigh meat from Cobb and Ross 308 chickens regarding the rearing environment. One-day-old Cobb and Ross broilers were raised for 35 days in conventional and animal welfare farms with, amongst others, different floor sizes, stock densities, and ammonia concentrations. One-dimensional ¹H nuclear magnetic resonance, orthogonal partial least squares-discriminant analysis (OPLS-DA), and pathway analyses were performed to analyze the metabolomic properties of broiler meat. For breast meat, only those from the Ross strain could be separated according to the environment in the OPLS-DA plot. Ross breast meat from animal welfare farms showed significantly higher acetate, anserine, creatine, and inosine monophosphate content than those from conventional farms (<i>P</i>&lt;0.05). In contrast, for thigh meat, the Cobb strain was differentiated using OPLS-DA. The contents of five metabolites, such as glucose and lactate, were higher in thigh meat from animal welfare farms; however, nine metabolites, including seven free amino acids, were lower compared to those from conventional farms (<i>P</i>&lt;0.05). Pathway analysis was performed to interpret the biological changes in chicken meat based on environmental factors. The results indicated that the animal welfare environment led to significant changes in four metabolic pathways in Ross breast meat and in 20 metabolic pathways in Cobb thigh meat (<i>P</i>&lt;0.05). In conclusion, the animal welfare environment could influence the metabolomic properties of Ross breast meat and Cobb thigh meat, which may affect the sensory quality of meat.

The Effects of Using Pineapple Stem Starch as an Alternative Starch Source and Ageing Period on Meat Quality, Texture Profile, Ribonucleotide Content, and Fatty Acid Composition of Longissimus Thoracis of Fattening Dairy Steers.

The effects of different starch sources (ground corn (CO), ground cassava (CA) and pineapple stem starch (PI)) and ageing period (14 and 21 days) on meat characteristics of Holstein steers were investigated. Starch sources had no effect on meat characteristics, while meat aged for 14 days had less thawing loss than that aged for 21 days. Meat from steers fed PI had higher levels of inosine monophosphate (IMP) than the others (p < 0.05). With increasing duration of ageing, the content of IMP and guanosine monophosphate in the meat decreased, while the content of hypoxanthine increased (p < 0.05). Meat from steers fed CO had the highest oleic acid but the lowest erucic acid (p < 0.05) in contrast to meat from steers fed PI, which had the lowest oleic acid but the highest erucic acid. Steers fed CO appeared to produce healthier meat as this was positively associated with monounsaturated fatty acid content. Meat from steers fed PI had higher levels of IMP, which may be associated with good taste.

Underlying mechanisms of phosphodiesterase 10A and glutamate-ammonia ligase genes that regulate inosine monophosphate deposition and thereby affect muscle tenderness in Jingyuan chickens.

Inosine monophosphate (IMP) is a key factor that imparts of meat flavor. Differences in the IMP content in the muscles were evaluated to improve chicken meat quality. For this study, the IMP content was detected by high performance liquid chromatography. The gene expression profiles of Jingyuan chickens with different feeding patterns and different sexes were analyzed by RNA-sequencing (RNA-seq). Breast muscle IMP content in free-range chickens was extremely significantly higher than that of caged chickens (p<0.01). Breast muscle IMP content in hens was also higher than that of cocks, but the difference was not significant. Correlation analysis showed that the breast muscle IMP content in caged hens and cocks was negatively correlated with the shear force, and the breast muscle IMP content in free-range hens was significantly negatively correlated with the shear force (p<0.05). The two key genes associated with IMP synthesis in chickens with different feeding patterns were glutamate-ammonia ligase (GLUL) and phosphodiesterase 10A (PDE10A). Bioinformatics analysis revealed that the GLUL and PDE10A genes are involved in glutamine biosynthesis and purine salvage pathways respectively. In addition, GLUL expression was positively correlated with the IMP content in caged and free-range chickens, and PDE10A expression was significantly positively correlated with the IMP content in caged and free-range chickens (p<0.05). These findings will facilitate the comprehension of the deposition of IMP in the muscles and thereby aid the process of selection and breeding of good quality local chickens.

Effect of hypoxia on purine metabolism of human skeletal muscle cells

Mammals experience some degree of hypoxia during their lifetime. In response to hypoxic challenge, mammalian cells orchestrate specific responses at transcriptional and posttranslational level which lead to changes in the purine metabolites in order to cope with threatening conditions. The aim of this study was to evaluate the response of the enzymes involved in the purine metabolism of human muscle cells to hypoxic conditions. Muscle cells in culture were exposed to hypoxia and the enzymatic activity of inosine monophosphate dehydrogenase (IMPDH), xanthine oxidase (XO), purine nucleoside phosphorylase (PNP) and hypoxanthine guanine phosphoribosyl transferase (HGPRT) as well as their transcript expression were quantified under normoxic and hypoxic conditions. Purine metabolite (hypoxanthine (HX), xanthine (X), uric acid (UA), inosine monophosphate (IMP), inosine, nicotinamide adenine dinucleotide (NAD+), adenosine, adenosine monophosphate (AMP), adenosine diphosphate (ADP), adenosine triphosphate (ATP), guanosine diphosphate (GDP) and guanosine triphosphate (GTP)) concentrations were also quantified. Significant reduction of IMPDH activity and HX and IMP concentrations (p &lt; 0.05) were observed after hypoxia, suggesting a decrease of de novo synthesis of purines. After hypoxia a global reduction of transcripts was observed, suggesting a reduction of the metabolic machinery of purine metabolism to new steady states that balance ATP demand and ATP supply pathways.

The significant influence of residual feed intake on flavor precursors and biomolecules in slow-growing Korat chicken meat.

ObjectiveThis study investigated the association between feed efficiency, physicochemical properties, flavor precursors and biomolecules in the thigh meat of Korat (KR) chickens.MethodsThe feed intake and body weight of individual male KR chickens were recorded from 1 to 10 weeks old to calculate the individual residual feed intake (RFI) of 75 birds. At 10 weeks of age, chickens with the 10 highest (HRFI) and lowest RFI (LRFI) were slaughtered to provide thigh meat samples. The physicochemical properties (ultimate pH, water holding capacity [WHC], drip loss) and flavor precursors (guanosine monophosphate, inosine monophosphate (IMP), adenosine monophosphate and inosine) were analyzed conventionally, and Fourier transform infrared spectroscopy was used to identify the composition of biomolecules (lipids, ester lipids, amide I, amide II, amide III, and carbohydrates) and the secondary structure of the proteins. A group t-test was used to determine significant differences between mean values and principal component analysis to classify thigh meat samples into LRFI and HRFI KR chickens.ResultsThe physicochemical properties of thigh meat samples from LRFI and HRFI KR chickens were not significantly different but the IMP content, ratios of lipid, lipid ester, protein (amide I, amide II) were significantly different (p<0.05). The correlation loading results showed that the LRFI group was correlated with high ratios of lipids, lipid esters, collagen content (amide III) and beta sheet protein (rg loading >0.5) while the HRFI group was positively correlated with protein (amide I, amide II), alpha helix protein, IMP content, carbohydrate, ultimate pH and WHC (rg loading >0.5).ConclusionThe thigh meat from chickens with different RFI differed in physiochemical properties affecting meat texture, and in the contents of flavor precursors and biomolecules affecting the nutritional value of meat. This information can help animal breeders to make genetic improvements by taking more account of traits related to RFI.

Changes of the flavor substances and protein degradation of black carp (Mylopharyngodon piceus) pickled products during steaming

Among various cooking methods, steaming is favored by many because it can cause less damage to nutrient components in muscle, retain the inherent food flavor, and reduce the generation of harmful substances. Steaming conditions are closely related to fish flavor, fat and protein oxidation, and digestibility. The black carp steamed for 4 to 14 min was studied in this article based on sensory assessment, electronic tongue, free amino acids, adenosine triphosphate (ATP)-related compounds, total nitrogen and non-protein nitrogen to explore the effect of steaming time on the taste substances and protein degradation of pickled black carp. The experimental result showed that the meat steamed within 8min tasted better, showing high tastiness. The sensory assessment score increased significantly to the maximum value of 82.33 at 6min. The content of umami and sweet amino acids increased significantly to the maximum value of 1.6801 g kg-1 at 6min. In the meantime, the IMP (inosine monophosphate) content was 1.9128 g kg-1 , with its taste activity value (TAV) reaching 7.65, which proved that IMP affected the taste most. Furthermore, the total nitrogen content was 30.77 g kg-1 , which meant protein degraded a great deal. Based on equivalent umami concentration (EUC) and its TAV, the meat tasted best at 6-8min. The longer the steaming time, the faster the protein degradation and the more the flavor precursors. The black carp pickled products (with a weight of 20 g, with the size of 3cm × 3 cm × 2cm) is suggested to be steamed for 6 to 8min. This conclusion provides a theoretical basis for its better taste quality. © 2020 Society of Chemical Industry.

Nucleotide degradation, biogenic amine level and microbial contamination as quality indicators of cold-stored rainbow trout (Oncorhynchus mykiss) gravad

The extent to which the transformation of nucleotides, biogenic amines, and microbiological changes affect the quality and shelf life of vacuum packaged low processed rainbow trout (Oncorhynchus mykiss) gravad during storage at 7 ± 1 °C for 42 days was investigated. Although total viable counts increased slowly up to 6 log CFU g−1 at the end of storage, coliform bacteria disappeared. The histamine concentration and the biogenic amine index increased up to 45.2 ± 1.62 mg kg−1 and 100 mg kg−1 respectively. The highest concentration of inosine monophosphate was achieved in freshly prepared gravad, whereas the hypoxanthine level increased with storage time up to 28 days. Among nucleotide ratios, the G value is more suitable for the determination of gravad quality than K, Ki and H values. Once the gravad obtained the limit of acceptability by the panelists (35 days) the G value rose to 470%.

Different dietary starch sources alter the carcass traits, meat quality, and the profile of muscle amino acid and fatty acid in finishing pigs

BackgroundWith increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis (L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen. Tapioca starch (TS), corn starch (CS), and pea starch (PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44, respectively, were used as their dietary starch sources for 40 days.ResultsResults showed that the PS diet significantly increased (P < 0.05) the final body weight, average daily gain, loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased (P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased (P < 0.05) the pH45 min, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased (P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased (P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid (PUFA) in the L. thoracis compared with TS diet, but decreased (P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated (P < 0.05) the lipogenic genes (FAS, LPL, SCD, ACCα) and myosin heavy-chain (MyHC)-IIa mRNA expression levels compared with the TS diet, but downregulated (P < 0.05) the CPT1B and MyHC-IIb mRNA levels.ConclusionsIn conclusion, these results provided compelling evidence that the different dietary starch source altered the carcass traits, meat flavor and quality in finishing pigs, and consumption of a diet with higher amylose/amylopectin ratio results in the production of a healthy, higher quality, and nutritional value pork.

Below-zero storage of fish to suppress loss of freshness

The decomposition of ATP in flounder and greenling muscle were compared at 0 and − 2 °C. The decomposition of inosine-5-monophosphate (IMP) and subsequent increase in the K-value were suppressed at − 2 °C for both species, although the K-value increased much more slowly for flounder than for greenling. When flounder was stored at 0 °C, a high IMP content was maintained for more than 10 days, and then dropped quickly. This quick reduction in the IMP content was not observed at − 2 °C. The fast reduction in the IMP content at 0 °C was explained by the activity of an IMP-decomposing enzyme produced by spoilage microorganisms; it no longer occurred when the meat was stored in the presence of 150 p.p.m. of the antibiotic chloramphenicol. 5′-Nucleotidase produced by the bacteria was less stable than that produced endogenously. Spoilage bacteria also produced a strong protease that degraded muscle protein. It was concluded that lowering the storage temperature of flounder and greenling from 0 to − 2 °C suppressed the growth of spoilage bacteria and slowed the increase in the K-value.

Condition‐dependent adenosine monophosphate decomposition pathways in striated adductor muscle from Japanese scallop (Patinopecten yessoensis)

The purpose of this study was to confirm inosine monophosphate (IMP) generation and to clarify the decomposition pathway of adenosine monophosphate (AMP) by investigating the properties of AMP, IMP, and adenosine (AdR) decomposition enzymes in Japanese scallop (Patinopecten yessoensis). The results showed that IMP accumulated due to AMP decomposition via endogenous enzymes in scallops stored at both 4 °C and 20 °C. The AMP decomposition rate was highest in the supernatant of homogenized scallop adductor muscle, followed by the suspended solution and precipitate, while IMP could not be decomposed in scallop. The results indicated that the activity of AdR deaminase was very high, and this enzyme was involved in an intracellular process in scallop. Moreover, 1 min of heating exerted little influence on the AMP and AdR decomposition rates, while 5min of heating induced enzyme denaturation. The IMP generation rate increased dramatically in scallop crude enzyme solution containing 5mM ethylenediaminetetraacetic acid (EDTA). This suggests that the major pathway of AMP decomposition might change with variations in metal ion concentrations in Japanese scallop. PRACTICAL APPLICATION: IMP generation in Japanese scallop (Patinopecten yessoensis) caused by endogenous enzymes was confirmed. IMP is very important for the umami taste (a pleasant savory taste) of aquatic products. As IMP accumulation might be achieved by changing the concentration of divalent metal ions and no IMP 5'-nucleotidase activity was detected in scallop, a suitable process to produce good flavor scallops with high IMP contents might be developed.

Naringin supplementation affects performance, carcass traits, meat quality and oxidative stability of finishing pigs

Naringin is a major flavanone derivate that has many important biological functions in animals. However, its effect on pigs is unknown. The aim of this study was to investigate the effect of naringin supplementation on performance, carcass traits, meat quality and oxidative stability in finishing pigs. Ninety-six pigs, with an average initial body weight of 66.2 ± 0.63 kg, were randomly divided into four groups. One group was fed a basal diet without supplementation (control), and the three others were fed diets supplemented with 0.5, 1.0 or 1.5 g naringin /kg DM of feed for 50 days. Each treatment was replicated six times with four pigs per replicate. Feed and water were available ad libitum. The 0.5 g/kg naringin treatment group had an improved loin eye muscle area, reduced serum triglycerides and were leaner compared with the other groups. Pigs in the 1.5 g/kg naringin treatment had higher pH45min values and inosine monophosphate concentrations, and lower MyHC IIb mRNA expression in muscle than the other groups. MyHC IIa mRNA expression was significantly up-regulated in all naringin-supplemented diet groups. Naringin significantly increased superoxide dismutase (SOD) activity and total anti-oxidative capacity in meat, as well as SOD and glutathione peroxidase activity in the liver. These results indicate that the dietary addition of naringin at 0.5 g/kg improved carcass characteristics, while 1.5 g/kg improved the oxidative stability and pork quality in finishing pigs.&#x0D; Keywords: antioxidant capacity; carcass characteristics; naringin-supplemented diets; pork quality

Correlation Analysis between AK1 mRNA Expression and Inosine Monophosphate Deposition in Jingyuan Chickens.

Simple SummaryChina is rich in livestock and poultry resources, but the development of animal husbandry in different regions is uneven, and excellent livestock and poultry resources have to be developed. Jingyuan chicken is a national-level protected breed of livestock and poultry and a genetically protected breed in the Ningxia Hui Autonomous Region. It is rich in amino acids and fatty acids, with a high nutritional value. It is the first choice of “green nutrition and health care” in chicken food. Meat flavor is the main factor affecting meat quality. Meat flavor is characterized by umami and aroma properties. Inosine acid (inosincacid, inosinemonphosphate, IMP) has the greatest influence on meat flavor and is an important indicator of the freshness of meat. The purpose of this study was to screen out differentially expressed genes related to IMP content in different parts of the Ningxia local breed of Jingyuan chicken on the basis of transcriptome sequencing, and select adenylate kinase 1 (AK1) for quantitative fluorescence verification and Pearson correlation analysis. These findings provide a theoretical basis for further discovery and screening of IMP-specific deposition regulation mechanisms, as well as scientific basis for the development and utilization of local varieties and the development of new approaches to molecular breeding.In this study, we examined correlations between the deposition of inosine monophosphate (IMP) and mRNA expression of the adenylate kinase 1 (AK1) gene in Jingyuan chicken. The IMP content was determined by high-performance liquid chromatography. Transcriptome sequencing was used to screen the differentially expressed gene AK1 and real-time quantitative polymerase chain reaction (PCR) to determine the expression level of AK1 mRNA associated with IMP synthesis. IMP and inosine content in the breast muscles of both Jingyuan cocks and hens was found to be significantly higher than that in the leg muscles. Similarly, the expression of AK1 mRNA in the breast muscles of cocks and hens was significantly higher than that in the leg muscles. Moreover, AK1 mRNA expression in cock breast muscles was negatively correlated with IMP content, whereas its expression in cock leg muscles was positively correlated with IMP content. In contrast, the expression of AK1 mRNA in hen breast and leg muscles was significantly positively correlated with IMP content. These findings provide a scientific basis for enhancing the meat flavor of Jingyuan chicken and promoting the development and utilization of local variety resources, as well as constituting a basis for screening IMP-regulated genes. Our study will advance our current understanding of AK1 function.

Comparison of carcass and meat quality traits between lean and fat Pekin ducks.

ObjectiveAccording to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement.MethodsA total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively.ResultsThe results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05).ConclusionLong-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

276 Effects of Hermetia illucens larvae meal on growth performance, carcass traits, and meat quality in finishing pigs

Abstract Object: This study aimed to investigate the effects of Hermetia illucens larvae meal on growth performance, carcass traits, and meat quality of finishing pigs. Methods: Seventy-two crossbred (Duroc × Landrace × Large White) pigs (76.0 ± 0.52 kg) were randomly allocated to three experimental treatments, and fed the diet with supplementation of 0%, 4%, or 8% Hermetia illucens larvae meal (HILM), respectively. The experiment lasted 42 days. Results: The average daily gain (ADG) of pigs in 4% HILM group was higher, and the feed gain ratio (F/G) was lower than the control and 8% HILM group (P &amp;lt; 0.05). The loin-eye area, marbling scores, and inosine monophosphate (IMP) content of Longissimus thoracis muscle (LM) in 4% and 8% HILM group were higher than the control group (P &amp;lt; 0.05). There were no diffenences on backfat thickness, pH value, meat color, drip loss among three groups. Compared with the control, 4% HILM significantly increased the content of intramuscular fat (IMF) (P &amp;lt; 0.05). Meanwhile, the mRNA expression level of fatty acid synthase (FAS), acetyl CoA carboxylase α (ACCα), lipoprotein lipase (LPL), and MyHC-IIa in the LM was higher in 4% HILM group than that in 8% Hermetia illucens larvae meal and the control group (P &amp;lt; 0.05). The abundance of Lactobacillus, Pseudobutyrivibrio, Roseburia, Oribacterium, and Faecalibacterium was higher in 4% Hermetia illucens larvae meal group than the control group (P &amp;lt; 0.05); The abundance of Streptococcus was lower and Peptococcus was higher in 4% HILM group than 8% HILM group. Conclusion: HILM can be used as an effective feed ingredient in finishing pig’ diet up to 4% level, which was beneficial for the growth performance, carcass trait, and meat quality of pigs, and the underlying mechanism maybe due to the altered lipogenic potential, myofiber characteristics and the microbial composition regulated by HILM.

Detection of Inosine Monophosphate (IMP) in Meat Using Double-Enzyme Sensor

Inosine monophosphate (IMP) was considered to be an important component of meat flavor and an important indicator for evaluating the quality of meat products. This paper developed a novel dual-enzyme biosensor for the quantitative detection of inosinic acid to assess meat quality. Using the conductivity of MXene materials and the ability of Au@Pt nanoflowers to catalyze the oxidation of H2O2, a dual-enzyme biosensor was assembled and prepared for sensitive and rapid detection of IMP. The MXene-Ti3C2Tx material had 2D nanostructure similar to that of graphene, as well as metal conductivity and good biocompatibility. MXene was used as a carrier for 5′-nucleotidase and xanthine oxidase, with good biological environment and stable microenvironment. Bimetallic nanoflowers with a core-shell structure had better ability to catalyze H2O2 than the single metal. The double-enzyme hydrolyzed IMP to produce the H2O2. The Au@Pt nanoflowers of the sensor can catalyze the decomposition of H2O2, which causes electron transfer to produce current change. Therefore, the content of IMP is indirectly obtained by monitoring the current change. The results showed that the linear range of the double-enzyme biosensor was 0.04~17 g L−1, the correlation coefficient was 0.9964, and the detection limit was 2.73 ng mL−1. The biosensor had great reproducibility and stability. Compared with high-performance liquid chromatography, biosensors could quickly and accurately detect the content of inosine monophosphate in meat, and provided a better method to detect the quality index of meat products.

Use of Hermetia illucens larvae as a dietary protein source: Effects on growth performance, carcass traits, and meat quality in finishing pigs

This study investigated the effects of feeding Hermetia illucens larvae (0, 4, and 8%; HI0, HI4, and HI8 groups, respectively) on growth performance, carcass traits, and meat quality of finishing pigs. Results showed that the HI4 diet increased (P < .05) final body weight and average daily gain and decreased (P < .05) feed to gain ratio compared with HI0 and HI8 group. HI4 and HI8 diets increased (P < .05) loin-eye area, marbling scores, and inosine monophosphate content of longissimus thoracis (LT) compared with HI0 diet. The intramuscular fat content was greater (P < .05) in HI4 group than in the HI0 group. Furthermore, HI4 diet up-regulated (P < .05) lipogenic genes and MyHC-IIa mRNA levels in LT compared with HI0 diet. Our results indicated that dietary inclusion of H. illucens larvae has a beneficial impact on growth performance and meat quality, and the underlying mechanism may be due to the altered lipogenic potential induced by H. illucens larvae.