ATP-related Compounds Research Articles

Coating Effects of ε-Polylysine and Rosmarinic Acid Combined with Chitosan on the Storage Quality of Fresh Half-Smooth Tongue Sole (Cynoglossus semilaevis Günther) Fillets

The study was to evaluate the effects of chitosan-based coating combined with rosmarinic acid (RA) with different concentrations of ε-polylysine (ε-PL) on flavor retention and sensorial properties of half-smooth tongue sole fillets during storage at 4 °C. Results showed that chitosan-based coatings combined with ε-PL and RA contributed to the reduction of off-flavor compounds, such as total volatile base nitrogen (TVB-N), trimethylamine (TMA), and ATP-related compounds, and accumulation of free amino acids (FAAs). Nineteen volatile organic compounds were analyzed by gas chromatography-mass spectrometer (GC/MS) during storage, including seven alcohols, six aldehydes, and six ketones. The coating treated fresh half-smooth tongue sole (HTS) fillets significantly reduced the relative content of off-odor volatiles, such as 1-octen-3-ol, propanal, hexanal, and octanal. According to sensory evaluation results, chitosan-based coating combined with ε-PL and RA was an effective way to maintain quality of HTS fillets during refrigerated storage.

Effects of pomegranate peel extract on quality and microbiota composition of bighead carp (Aristichthys nobilis) fillets during chilled storage

This study aimed to investigate effects of aqueous pomegranate peel extract (APPE) and ethanolic pomegranate peel extract (EPPE) on microbiota and changes in quality of bighead carp (Aristichthys nobilis) fillets stored at 4 °C. The results showed that pomegranate peel extract (PPE, which includes both APPE and EPPE) retarded the deterioration of sensory quality and flesh color, inhibited the growth of spoilage bacteria, and attenuated the production of biogenic amines, total volatile basic nitrogen (TVB-N), and the degradation of ATP-related compounds. Moreover, EPPE performed better in color attributes and biogenic amines, but APPE was more effective in retarding the increase of TVB-N and K-value. High-throughput sequencing results showed that microbial composition of all samples became less diverse as storage time increased. For the control group, Acinetobacter was predominant in the middle-period of storage, while Pseudomonas, Aeromonas, and Shewanella became predominant at the end of storage. Additionally, PPE decreased the relative abundance of Acinetobacter in the middle-period of storage, and thus changed the microbial composition. Based on our assessments of quality and microbial analysis, PPE prolonged the shelf-life of bighead carp fillets for about 2 days, and it has the potential to become a promising preservative in aquatic products.

Evaluation of freshness in freshwater fish based on near infrared reflectance spectroscopy and chemometrics

Freshness is the primary quality attribute of bighead carp (Aristichthys nobilis). Determining freshness in bighead carp with near infrared reflectance spectroscopy (NIRS) combined with an appropriate multivariate regression method has potential and is relevant to the fish food industry, but it has been insufficiently exploited. In this study, a total of 150 samples were scanned in a reflectance mode covering the spectral range of 1000–1799 nm to determine freshness, which included measurement of pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and ATP-related compounds (K value). Prediction models of freshness parameters were developed and then validated using partial least-squares regression (PLSR) associated with a competitive adaptive reweighted sampling (CARS) algorithm and optimal pre-processing methods. This resulted in satisfactory coefficients of prediction (Rp) of 0.945, 0.932, 0.954, 0.807 and root mean square error of prediction (RMSEP) of 0.081, 2.099, 0.107, and 6.509 for pH, TVB-N, TBA, and K value, respectively. The overall results demonstrated the feasibility of using NIRS to determine freshness in fish flesh.

Study on changes in the quality of grass carp in the process of postmortem

Grass carp is an important freshwater fish but little is known about its quality postmortem. We tracked changes in the pH, texture, lactic acid, ATP-related compounds, K value, free amino acids (FAA) contents in grass carp stored at 4°C for 192 hr. Sensory and electronic tongue assessment were also performed. The results showed a consistent trend in the hardness and chewiness. pH were closely correlated with the lactic acid content and hardness. The fresh sweet amino acids gradually decreased with time while the opposite occurred with the bitter amino acids. The content of Hx and HxR increased gradually. The K value remained increased throughout the storage. Sensory assessment followed the opposite trend. The electronic tongue indicated that the differences were distributed in various areas between the first 2 days and the last 6 days. Overall, we recommend that grass carp should be consumed within 6 days when stored at 4°C. Practical applications In fish, the process of quality change after death can normally be divided into four stages: the early biochemical change, rigidity and dissolving, self-dissolution and finally, corruption. Rigidity can delay the process of corruption somewhat as fish in the rigid period are almost as fresh as newly caught fish. Preservation may thus be described as an extension of the period of rigor mortis. Postmortem changes in grass carp meat were studied over a period of 192 hr by measuring its pH, texture properties, lactic acid, ATP-related compounds, K values, and FAA content. Sensory assessment and electronic tongue measurements were also conducted. In addition to establishing a theoretical basis for the quality control and processing of grass carp, these results provide useful information for manufacturers and product developers seeking to improve the quality of their grass carp products and will also provide farmers with valuable insights into quality retention.

Effects of a freeze-thaw-pressing muscle separation on the biochemical quality and self-stability of leg meat from red snow crab (Chionoecetes japonicus)

To evaluate the product quality of leg meat from red snow crab (Chionoecetes japonicus) prepared with a novel freeze-thaw-pressing muscle separation (FTPS), the biochemical properties were compared with those of two thermal muscle separations (boiling; BS or steaming; SS). Among the muscle separations, the yield from merus part was the highest with the FTPS (22.0 ± 2.1 g), followed by SS (20.3 ± 1.4 g) and BS (17.5 ± 1.8 g). The proximate compositions in the three leg meats were similar, but the quantitative analyses for the water extractive components (free amino acids, minerals, organic acids and ATP-related compounds) revealed that all the contents were notably higher in the leg meat with FTPS (LM-FTPS) than that with BS or SS. The sensorial acceptability test demonstrated the storable day limits of the LM-FTPS at −20 °C, 0 °C or 10 °C, but it was suggested only in storage either at 0 °C (3 days) or 10 °C (1 day), the day limits corresponded to 30 mg% of the VBN value and 5 log CFU g−1 of the total viable cell count. In the case of −20 °C storage, the storable day limit suggested within 5 days, based on the VBN value.

A convenient and nondestructive method using bio-impedance analysis to determine fish freshness during ice storage

Fish freshness can be assessed through K values, but this method has a number of limitations, including a complex procedure and destructive sampling. With the aim to develop a convenient method of assessing fish freshness, we measured the changes in K values (up to 40%) and bio-impedance (Z value; frequency 2, 5, 20, 50, 100 kHz) of ordinary muscle in fish of eight marine species, all caught in the East China Sea, during ice storage and examined their relationships. The results indicated that the K value in all fishes increased linearly with storage time, while their Z value decreased only after 24 h of storage. Moreover, after 24 h of storage and at K values of < 40%, impedance ratios at 2–100 kHz (C value, C = Z2 kHz/Z100 kHz) were significantly correlated (p < 0.05) with both storage time and K values in all fishes. These findings suggest that the bio-impedance ratio effectively reflects the change in ATP-related compounds of fish and that a convenient, nondestructive method using the C value can be used instead of the complicated K value measurement to assess the freshness of marine fishes after 24 h of ice storage.

Smart technique for accurate monitoring of ATP content in frozen fish fillets using fluorescence fingerprint

The aim of the present study was to develop a fast and nondestructive method based on fluorescence fingerprints (FFs) to predict the ATP content in frozen fish meat frozen at early stages after death using fillets of horse mackerel (Trachurus japonicus) as a model. Fifty-six fish were sacrificed instantly, stored in ice for different periods (0–48 h), and then filleted and frozen. The fluorescence fingerprints of the frozen fillet samples were acquired using fluorescence spectrophotometer with fiber probe installed inside a freezer. Subsequently, the ATP-related compounds of the same samples were determined using HPLC. Finally, four different models based on partial least squares (PLS) were developed to predict ATP contents from HPLC and the FFs data. The best PLS model with a correlation coefficient (R2) of 0.88 and root mean square error estimated by cross validation (RMSECV) of 0.97 μmol/g was obtained when the most important combinations of excitation-emission wavelengths were used for prediction. This methodology offers a simple and rapid approach to detect the ATP contents in frozen fish nondestructively without thawing the sample during the assessment that could be applied during any stage of fish marketing, facilitating quality control activities and the determination of fishery market price.

Protective Effect of an Edible Tomato Plant Extract/Chitosan Coating on the Quality and Shelf Life of Sierra Fish Fillets

The products of fishing are highly perishable foods. Thus, it is necessary to seek viable alternatives that help to preserve product freshness and quality and to increase its shelf life. One of these alternatives is the use of extracts with antimicrobial activity obtained from plants, such as tomato, which has been observed to present compounds with antimicrobial activity. The objective of this work was to determine the effect of an extract obtained from the tomato plant and incorporated into an edible chitosan coating on the quality and shelf life of the sierra fish fillet stored on ice for 15 days. For the latter, an extract was prepared with dehydrated tomato plants, which was incorporated by immersion alone or in combination with an edible chitosan-based coating in sierra fish fillets. The following treatments were applied: C (Chitosan), TPE (Tomato Plant Extract), TPE-C (TPE-Chitosan), and control (without chitosan and extract). Color, pH, WHC, ATP-related compounds, and K value were monitored during 15 days of storage on ice. Likewise, the total count of mesophiles was determined. The results indicated that treatments C, TPE, and TPE-C were significantly different (p&lt;0.05) from lot control in terms of the concentration of ATP-related compounds, K value, pH, and total mesophilic count. We concluded that application of the extract alone or in combination with chitosan allows for the improvement of the quality and shelf life of the sierra fish fillet.

Quality changes and microbiological spoilage analysis of air-packed and vacuum-packed silver carp (Hypophthalmichthys molitrix ) fillets during chilled storage

The effects of air-packed (AP) and vacuum-packed (VP) on quality and microbial characteristics of silver carp (Hypophthalmichthys molitrix) fillets during chilled storage (4 ± 1 °C) were investigated. The fillets were analyzed for sensory scores, total volatile basic nitrogen (TVB-N), ATP-related compounds (ATP, IMP, HxR, and Hx), K value, and biogenic amines (BAs). The results proved that VP inhibited the increase of microorganisms, TVB-N, Hx, and putrescine in silver carp, and slowed the reduction in sensory score. Therefore, VP can be applied for preservation of the silver carp fillets to improve its quality. For identification, 16S rRNA genes of the isolated pure strains were sequenced and analyzed. On the initial day of storage, Chryseobacterium was the dominant bacterial genus. At the end of shelf life, Pseudomonas was the most common group in AP fillets and Aeromonas followed by Yersinia were found mainly in VP samples. Practical applications Silver carp (Hypophthalmichthys molitrix) are distributed widely in fresh water systems. The world aquaculture production of silver carp was 4,354,638 tons, and it ranked second highest among freshwater fish species in 2015, but they are perishable during storage because of microbial spoilage and biochemical reactions. Vacuum packaging (VP) has proved to be effective for extending the shelf-life of aquatic products by excluding oxygen that prevents the growth of spoilage bacterial. However, little information is available on the microbial succession of VP silver carp. Therefore, this work was to determine the differences of microbiological succession on chilled silver carp fillets under air-packed (AP) and VP conditions using a combination of culture-based and 16S rRNA gene analysis methods. Furthermore, this study will give valuable information about development and spoilage of VP silver carp fillets.

Changes in volatile compounds, ATP-related compounds and antioxidative properties of Kapi, produced from Acetes vulgaris, during processing and fermentation

Abstracts During salting, drying and fermentation for making Kapi (salted shrimp paste of Thailand), from Acetes vulgaris , Maillard reaction products (MRPs), adenosine triphosphate (ATP)-related compounds, antioxidative activities and volatile compounds were monitored. Varying colors were observed during processing. The results of the study showed that L* and b*- value decreased, while a*- value increased as fermentation time increased (p 420 ) (p Kapi contained hypoxanthine (Hx) (112.49 mg/ 100 g dry sample) as the most abundant ATP-related compound. Aldehydes, ketones as well as N-containing compounds increased as fermentation time increased (p Kapi . Moreover, antioxidative activities increased, particularly when fermentation proceeded, as evidenced by the increases in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, and ferric reducing antioxidant power (FRAP) (p Kapi took place throughout all processes. However, odorous compounds and flavorants were mainly formed during fermentation process. Those compounds were plausibly involved in the unique flavor/taste of Kapi .

Changes in quality of rainbow trout (Oncorhynchus mykiss) fillets preserved with salt and sugar at low concentrations and stored at 4°C

ABSTRACTThe effects of dry-curing with low concentrations of salt and sugar on the quality of rainbow trout (Oncorhynchus mykiss) fillets were studied over a 16-day storage period at 4°C. Physicochemical characteristics (total volatile base nitrogen (TVB-N), biogenic amines (BAs), ATP-related compounds and K value), microbial populations (total aerobic counts (TAC), H2S-producing bacteria, Pseudomonas, Aeromonas, and lactic acid bacteria) and sensory (SA) indicators were analyzed. Fish samples were subjected to the following treatments: untreated (control), dry-cured with 1.3% salt (T1), and dry-cured with 1.3% salt that also contained 0.9% sugar (T2). SA indicated that the sensory quality of the control, T1, and T2 was unacceptable after 8, 12, and 12 days of storage, respectively. Moreover, the cadaverine concentration of treated samples was significantly lower (P < 0.05) than the control after storing for 8 days. T1 and T2 were significantly higher (P < 0.05) than the control in inosine 5-monophosphate (IMP) content from the 2th to 10th day. Cadaverine, putrescine, hypoxanthine, and TAC were correlated significantly (P < 0.01) with SA, and these seemed to be reliable indicators of fish quality. The results indicated that curing treatments extended the shelf life of rainbow trout fillets, which could be exploited by processors.

Comparison of postmortem changes in ATP-related compounds, protein degradation and endogenous enzyme activity of white muscle and dark muscle from common carp (Cyprinus carpio) stored at 4 °C

Postmortem changes in white muscle and dark muscle of common carp (Cyprinus carpio) during 72 h at 4 °C were evaluated by determining ATP-related compounds, AMP-deaminase (ADA) activity, acid phosphatase (ACP) activity, pH, texture properties, contents and SDS-PAGE patterns of myofibrillar and sarcoplasmic proteins, as well as activity of cathepsins B and B + L. The results showed that white muscle had a significantly (P < 0.05) higher pH and inosine monophosphate (IMP) concentration but a lower hardness after slaughter. Higher activity of ADA and ACP in dark muscle coincided with its higher K value. The SDS-PAGE patterns showed that white muscle contained more protein bands for myofibrillar and sarcoplasmic proteins, while dark muscle had more bands with low molecular weights for sarcoplasmic protein. Cathepsins B and B + L showed higher activity in dark muscle than in white muscle, especially at the later period of storage. Higher activity of endogenous enzymes in dark muscle might contribute to its faster quality loss.

Effect of ginger extract and vinegar on ATP metabolites, IMP‐related enzyme activity, reducing sugars and phosphorylated sugars in silver carp during postslaughter storage

SummaryThis study aimed to investigate the utilisation of ginger extract and vinegar for retarding decomposition of inosine monophosphate (IMP), and IMP‐related enzyme activity (the activity of acid phosphatase (ACP) and alkaline phosphatase (ALP)) in salted silver carp (Hypophthalmichthys molitrix) during early postslaughter and chilled storage. We also quantified the decomposition pathway of ATP‐related compounds, the reducing and phosphorylated sugar, and free amino acids (FAAs) in samples. Rapid glycolysis in control occurred during postmortem storage. Vinegar and ginger extract inhibited the activity of ACP and ALP, thereby inhibiting the decomposition of IMP and the increase in hypoxanthine (Hx). IMP concentrations in treated sample were significantly higher than those of the control. Moreover, vinegar and ginger extract promoted the increase in FAAs. Therefore, vinegar and ginger extract could inhibit ACP and ALP activities and contributed to the accumulation of IMP and FAAs in silver carp during chilled storage.

Search for an index for the taste of Japanese Black cattle beef by panel testing and chemical composition analysis.

To search for an index for chemical composition related to superior taste in Japanese Black beef, we conducted panel tests and analyzed the chemical composition of seven beef brands. Thirty-five sirloin beefs from five heifers were used in this study, sold under seven beef brands graded as more than A4 on the Japanese Meat Grade scale. The chemical composition analyses assessed both raw and roasted meat, the latter of which was roasted under the same conditions as those used for the panel test. Results of the panel test and chemical composition analyses revealed that fatty acid composition, sugar content, adenosine triphosphage (ATP)-related compounds, amino acid composition and odor composition in the sirloin meat differed among beef brands. Furthermore, the correlations of chemical compositions between roasted and raw meat were significantly high. Sugar content and ATP-related compounds in roasted meat were significantly correlated with the item 'overall evaluation' of the panel test. ATP-related compounds, such as inosinic acid, carnosine and taurine, in roasted and raw meat were correlated significantly with the item 'umami intensity' of the panel test. These results suggest that the composition of these components is important for an index related to the overall evaluation of beef.

Effects of Adding Salt and Sugar on the Quality and IMP-Related Enzyme Activity of Grass Carp (Ctebopharyngodon idellus ) Fillets During 0C Storage

The effects of adding small amounts of salt and sugar on the quality and IMP (inosine mono-phosphate)-related enzyme activity of grass carp (Ctenopharyngodon idellus) fillets were evaluated by quantifying pH, total volatile base nitrogen (TVB-N), color, sensory scores, ATP-related compounds, AMP deaminase and acid phosphatase (ACP) activity. Fish samples were left untreated (CK), or were dry-cured with 1.0% salt (T1) or 1.0% salt and 1.0% sugar (T2). Curing treatments decreased TVB-N accumulation, accelerated the conversion of ATP to IMP, and improved the level of IMP in grass carp. No significant differences (P > 0.05) were observed among CK, T1, and T2 for color. Among the nucleotide ratios (K, Ki, H, P, Fr, and G values), the K and H values were superior to the Ki, P, G, and Fr values as freshness indicators. IMP content showed a significant (P < 0.01) correlation with the sum of its precursor substance. Practical Applications Grass carp is one of the most important farmed species of freshwater fish worldwide. However, grass carp fillets are usually more perishable than most other foodstuffs because of their high levels of moisture and nutrients. Salting can prolong fish shelf life and enhance the flavor of fish. Moreover, ready-to-use, high-quality, safe food products have become popular. Therefore, it is an attractive tendency to process salted and prepared products to meet human consumption. Inosine monophosphate (IMP) contributes to the umami taste of fish products and umami taste is generally the most important sensory property affecting consumer acceptance. Thus, the present study investigates how low concentration of salt and sugar affects quality and IMP-related enzyme activity of grass carp. Salt and sugar can be used as not only safe ingredients for preservation, but flavor enhancer of fish. Additionally, using K or H value to monitor freshness changes of grass carp is feasible.

Physico-chemical and microbiological changes in commercial tilapia (Oreochromis niloticus) during cold storage

Background: The microbiological and chemical processes are the main responsible for deterioration of fresh fish. Therefore, it is essential to avoid these processes by applying good manufacturing practices during fish handling, distribution and storage. Objective: The aim of this paper was to evaluate the physico-chemical and microbial changes in commercial tilapia (Oreochromis niloticus) during cold storage in order to establish the shelf life since its arrival at the supermarket. Methods: 27 aquacultured tilapia specimens were analyzed at 0, 2, 4, and 7 days of storage at 4oC. Measurements of texture, color, water holding capacity, total volatile basic nitrogen (TVB-N), thiobarbituric acid index, ATP-related compounds, as well as microbial analyses were carried out. Results: The TVB-N content was high at the beginning of the study, remaining stable during the storage. Lipid oxidation of samples was minimum, so this process did not contribute to the fish spoilage. It was observed the breakdown of inosine-5’- monophosphate (IMP) into Ino (inosine), and Ino into Hx (hypoxantine). The texture parameters and colour underwent changes as a consequence of the fish spoilage. Low microbial counts were observed at day 0, but Enterobacteriaceae and mesophilic counts gradually increased throughout storage. Conclusions: The K1-value showed the progressive spoilage of the fish during the cold storage. The decrease of hardness and firmness confirmed the loss of quality throughout the time of study. The low microbial counts at the beginning of the study demonstrated the good quality of the tilapia; however, the increase of the mesophilic counts at the end of the studied period showed that tilapia was not fit for human consumption at day 7.

Changes in Biogenic Amines and ATP-Related Compounds and Their Relation to Other Quality Changes in Common Carp (Cyprinus carpio var. Jian) Stored at 20 and 0°C

Biogenic amines, ATP-related compounds, sensory attributes, total volatile basic nitrogen, microbial flora (total viable bacteria, Pseudomonas, Aeromonas, and H2S-producing bacteria), and free amino acids were determined in common carp (Cyprinus carpio var. Jian) stored at 20 and 0°C. Pseudomonas and H2S-producing bacteria became the dominant bacteria in carp stored at 20 and 0°C, whereas Aeromonas rapidly increased only in carp stored at 0°C. Inosine monophosphate, which is responsible for flavor and freshness, increased to a maximum of 2.37 μmol/g after 12 h at 20°C and to 4.72 μmol/g after 3 days at 0°C. Putrescine and cadaverine were the dominant amines in carp and their concentrations were significantly correlated (P < 0.05) with total volatile basic nitrogen and sensory scores in all samples during the storage. Significant correlations also were observed between histamine and total volatile basic nitrogen and sensory scores only in samples stored at 20°C. Arginine decreased while putrescine increased in all samples. A significant decrease (P < 0.05) in histidine was observed after 24 h of storage, which coincided with an increase in histamine after 36 h in samples stored at 20°C. Hypoxanthine concentrations were significantly correlated with the microbial species (P < 0.01) and sensory scores (P < 0.05) and seems to be a reliable marker for quality of carp fillets stored at 20 and 0°C.

The importance of ATP-related compounds for the freshness and flavor of post-mortem fish and shellfish muscle: A review

abstractATP degradation is one of the most important biochemical changes in the post-mortem muscle of fish and shellfish. This process has long been recognized as an accurate way to evaluate freshness of fish and shellfish product. This review updates and condenses the overall history and recent advances in understanding the role of ATP-related compounds in post-mortem fish and shellfish muscle including a discussion of key analytical methods, their use as a freshness indicator, their roles in flavor enhancement, the factors affecting their transitions, and the possible mechanisms responsible for their impact on flavor and freshness. Moreover, some challenges and future directions for research regarding ATP-related compounds in fish and shellfish flavor and freshness are presented. With increasing consumer demands for fresh products with extended shelf life, understanding the relationships between ATP-related compounds and their involvement in the freshness and umami taste is a prerequisite for assuring the high quality of fish and shellfish.

New kid on the block: does histamine get along with inflammation in amyotrophic lateral sclerosis?

Results from amyotrophic lateral sclerosis (ALS) patients and pre-clinical studies strongly suggest that systemic and CNS-intrinsic immune activation plays a central role in ALS pathogenesis. Microglial cells are emerging in this context as master regulators with a bi-functional role in the progression of the pathological response. They foster a pro-inflammatory setting through the production of cytotoxic cytokines and chemokines (M1 phenotype), after an aborted effort to sustain an anti-inflammatory environment for motor neurons through the release of beneficial cytokines and growth factors (M2 phenotype). In this review, we gather information meant to propose that histamine and ATP, which are released from mast cells, microglia and damaged neurons at sites of injury where they function as transmitters, have to be considered as new players in the ALS neuroinflammatory arena. After all, abnormal histamine and ATP signalling in the brain are already documented in neurodegenerative/neuroinflammatory conditions such as multiple sclerosis, Alzheimer and Parkinson's disease and, at present, histamine- as well as ATP-related compounds are in clinical trial for these same pathologies. Concerning ALS, while emerging data are now available about purinergic mechanisms, the involvement of histamine is basically unexplored. The circumstantial evidence that we present here thus constitutes a solid background for formulating novel hypotheses, stimulating a scientific debate and, most of all, inspiring future research. We deem that a new potential role of histamine in the setting of ALS neuroinflammation might find a fertile ground where to thrive. ALS is still a disease without a cure: why not to play with a new kid on the block?

Content Variations of ATP-Related Compounds and Quality Assessment of Tilapia Fillets during Iced Storage

To explore the biochemical changes of tilapia fillets during iced storage, contents of adenosine triphosphate (ATP) and its degradation products were monitored by high performance liquid chromatography (HPLC), along with ATPase and the freshness indicators such as the values ofK,Ki,H,Fr, total volatile base nitrogen (TVB-N) and thiobarbituric acid (TBA) were determined to evaluate the quality of iced tilapia fillets. The results showed that ATP, adenosine diphosphate (ADP) and adenosine monophosphate (AMP) in iced tilapia fillets degraded sharply into inosine monophosphate (IMP) at the first day of storage, then almost kept stable in a low level over the rest of iced storage time. Meanwhile, IMP degraded into hypoxantjine (Hx) and inosine (HxR) with the extending storage time, and Hx as well as HxR accumulated. The changes of values ofK,Ki,H,Frwith iced storage time presented a significant linear correlation (P&lt;0.01, r=0.945, 0.943, 0.924, -0.943, respectively). ATPase activities were associated with the degradation of ATP. The contents of IMP, Hx, HxR, values ofK,Ki,H,Frand ATPase activities can be used as practical and effective indicators for quality assessment of tilapia fillets during iced storage instead of TVB-N and TBA.