Meta-analysis of citrus-derived additives on chicken meat quality and safety: a comprehensive evaluation of acceptability, physicochemical properties, and microbial contamination

Citrus represents a valuable repository of antioxidant substances that possess the potential for the preservation of meat quality. This meta-analysis aimed to comprehensively assess the impact of citrus additives on the quality and safety of chicken meat. Adhering to the PRISMA protocol, we initially identified 103 relevant studies, from which 20 articles meeting specific criteria were selected for database construction. Through the amalgamation of diverse individual studies, this research provides a comprehensive overview of chicken meat quality and safety, with a specific focus on the influence of citrus-derived additives. Minimal alterations were observed in the nutritional quality of chicken meat concerning storage temperature and duration. The findings demonstrated a significant reduction in aerobic bacterial levels, with Citrus aurantiifolia exhibiting the highest efficacy (P < 0.01). Both extracted and nonextracted citrus components, applied through coating, curing, and marinating, effectively mitigated bacterial contamination. Notably, thiobarbituric acid reactive substances (TBARS) concentrations were significantly reduced, particularly with Citrus hystrix (P < 0.01). Total volatile base nitrogen (TVBN), an indicator of protein degradation, exhibited a decrease, with citrus extract displaying enhanced efficacy (P < 0.01). Chemical composition changes were marginal, except for a protein increase after storage (P < 0.01). Hedonic testing revealed varied preferences, indicating improvements in flavor, juiciness, and overall acceptability after storage (P < 0.01). The study underscores the effectiveness of citrus additives in preserving chicken meat quality, highlighting their antibacterial and antioxidant properties, despite some observed alterations in texture and chemical composition. Citrus additives have been proven successful in 1) mitigating adverse effects on chicken meat during storage, especially with Citrus hystrix exhibiting potent antimicrobial properties, and 2) enhancing the hedonic quality of chicken meat. This research strongly advocates for the application of citrus additives to uphold the quality and safety of chicken meat.

Impact of storage technologies and duration on insect pest population, post-harvest losses, and seed quality of stored chickpea in Ethiopia

Chickpea (Cicer arietinum L.) is the most important winter season food legume in Ethiopia. Despite being a major producer and consumer of chickpeas, Ethiopia experiences lower yields due to biotic and abiotic stresses, particularly insect pest infestations during storage. This study aimed to evaluate the impact of different storage technologies and durations on the losses of stored chickpea seeds in terms of both quantity and quality. The experiment involved five storage technologies and three durations, spanning a period of 6 months, with data collected at 2-month intervals. The results showed that the Purdue Improved Crop Storage (PICS) and Super GrainPro (SGP) bags effectively maintained intergranular temperature, seed moisture content, and relative humidity throughout the storage period, followed by the modified hermetic metal silo. In contrast, traditional bags exhibited a significant increase in these parameters. The PICS and SGP bags also exhibited the lowest numbers of total insect pests after 6 months, while the jute bags had the highest infestation. Common insect species found in the stored chickpea seeds were Callosobruchus chinensis (L.), Sitophilus oryzae (L.), and Tribolium confusum (duVal). Furthermore, hermetic bags (PICS and SGP) demonstrated the least grain damage and weight loss, while jute bags had relatively higher values. Seed viability was well maintained in hermetic bags but significantly decreased in traditional bags. Overall, hermetic storage technologies, such as the PICS and SGP bags, effectively suppressed insect development, reduced losses, and preserved seed viability without the need for insecticides. It is recommended that farmers use these hermetic storage bags after proper drying to enhance food security and income generation. By implementing these recommendations, Ethiopia can enhance its chickpea storage practices, reduce post-harvest losses, and contribute to improved food security and economic sustainability in the chickpea sector. © 2023 Society of Chemical Industry.

Extraction of Bioactive Compounds from Spent Coffee Grounds Using Ethanol and Acetone Aqueous Solutions

Given global coffee consumption, substantial quantities of spent coffee grounds (SCGs) are generated annually as a by-product of brewing coffee. SCG, although rich in bioactive compounds, is nowadays disposed of. The objective of this study is to compare, for the first time and from the same SCG, the efficiency of ethanol-water mixtures and acetone-water mixtures for the recovery of total polyphenols, chlorogenic acid, and caffeine. Acetone at 20% (m/m) was the most convenient solvent to extract all three bioactive compounds simultaneously, yielding 4.37 mg of GAE/g SCG for total polyphenols, chlorogenic acid (0.832 mg 5-CQA/g SCG), and caffeine (1.47 mg/g SCG). Additionally, this study aims to address some challenges associated with the industrial-scale utilization of SCG as a raw material, encompassing factors such as pre-treatment conditions (natural drying and oven drying), storage duration, and the kinetics of the extraction process. No significant difference was observed between the natural drying and oven drying of SCG. In terms of storage duration, it is advisable to process the SCG within less than 3-4 months of storage time. A significant decline of 82% and 70% in chlorogenic acid (5-CQA) and caffeine contents, respectively, was observed after eight months of storage. Furthermore, the kinetic study for the recovery of total polyphenols revealed that the optimal extraction times were 10 min for acetone at 20% and 40 min for water, with a yield increase of 28% and 34%, respectively. What is remarkable from the present study is the approach considered, using the simplest operating conditions (minimal time and solvent-to-solid ratio, and ambient temperature); hence, at an industrial scale, energy and resource consumption and equipment dimensions can be together reduced, leading to a more industrially sustainable extraction process.

Microbial Profiles of Meat at Different Stages of the Distribution Chain from the Abattoir to Retail Outlets

Meat has been found to be a prime vehicle for the dissemination of foodborne pathogens to humans worldwide. Microbial meat contaminants can cause food-borne diseases in humans. The threat to consumers by microbial meat contaminants necessitates the studying of meat microbial loads to prevent potential illnesses in consumers. Studies investigating the meat microbial loads in South Africa are limited. The objective of this study was to compare microbial contamination of different meat types from low-throughput (LTA) and high-throughput abattoirs (HTA) at three stages of the distribution chain from abattoir to retail outlets. Beef, pork, and mutton (n = 216) carcasses were sampled: during the loading process at the abattoirs, when off-loading at the supply points and during marketing. All samples were subjected to total bacterial count (TBC), coliform count (CC), presumptive Escherichia coli (E. coli) (PEC) and Staphylococcus aureus (S. aureus) detection. In mutton, TBC dominated at loading, CC was similar across distribution chain stages, PEC was the predominant microbial contaminant at the offloading stage at the HTA, but TBC was affected at loading, CC was similar across distribution chain stages, PEC was affected at loading, and S. aureus was affected at the display stage at the LTAs. In beef, TBC had similar levels at loading; CC and PEC dominated at the display stage for the HTAs. However, TBC was affected at the display stage; CC was similar across stages; PEC was affected at the offloading stage at the LTAs. In pork, higher contamination levels were discovered at the display stage, CC dominated at the loading stage, with PEC detected at offloading at the HTAs but TBC, CC, PEC and S. aureus were similar across stages at the LTAs. TBC, CC and PEC were affected by the storage period and meat supplier to meat shop distance whereas distance affected the TBC, CC and PEC. Meat supplier to meat shop distance negatively correlated with meat distribution chain stage but positively correlated with TBC, CC and PEC such as temperature. Temperature positively correlated with meat distribution chain stage and shop class. Meat distribution chain stage was negatively correlated with storage period, TBC, CC and PEC but positively correlated with shop class. Shop class negatively correlated with storage period, TBC, CC and PEC. Storage period positively correlated with TB, CC and PEC. TBC and meat type positively correlated with CC and PEC. CC positively correlated with PEC but negatively correlated with S. aureus such as PEC. In conclusion, mutton, pork and beef meat are susceptible to microbial contamination at distribution chain stages in abattoirs.

Egg quality, hatchability, gosling quality, and amino acid profile in albumen and newly-hatched goslings' serum as affected by egg storage

In modern poultry husbandry, storing fertilized eggs is a common measure to cope with the variable demands of the market and the maximum hatching capacity of the hatchery. However, this measure is harmful to the hatchability of eggs and the quality of newly hatched birds. Knowledge about the effects of storing fertilized eggs on the performance of goslings is still limited. The objective of this study was to investigate the effects of storing fertilized eggs on egg quality, hatchability, gosling quality, hatching weight, post-hatching growth performance, and amino acid profile in albumen and newly hatched goslings' serum. A total of 1,080 fertilized goose eggs (Jilin White goose) with a similar egg weight (126.56 ± 0.66 g) were used in this study. All eggs were distributed into 3 groups with 24 replicates per group and 15 eggs per replicate. The differences between groups were the storage duration of eggs (0, 7, or 14 d). We found that the Haugh unit, yolk weight, and eggshell weight decreased linearly, whereas the albumen pH increased linearly, with storage duration. Prolonging storage duration had negative effects on hatchability, hatching weight, post-hatching growth performance parameters, and gosling quality in a time-dependent manner. The analysis of the amino acid profile in albumen and newly-hatched goslings' serum showed that the amino acid content increased linearly with storage duration. Additionally, eggs stored for 14 d had the worst performance for all measured parameters. Therefore, we concluded that the storage of fertilized eggs negatively affects egg quality and post-hatching gosling quality. To produce high-quality goslings, it is necessary to shorten the storage duration for fertilized eggs.

Postharvest factors affect under-skin browning in 'Honey Gold' mango fruit

BACKGROUND

Under-Skin Browning (USB) is a physiological skin disorder that significantly reduces quality of 'Honey Gold' mango (HG) fruit. Relationships between potential causative factors (vibration, holding temperature, sap) and expression factors (enzymes activities, phenolic concentration, anatomy) were investigated.

RESULTS

USB incidence was 2.6-3.6-fold higher in ripe HG fruit vibrated for 3-18 h at 12 °C to simulate transport damage and held then at 12 °C for 8 days compared to control fruit held under the same conditions. USB severity of fruit lightly abraded with sand paper to simulate physical damage and artificially induce USB was higher in fruit held at 10 °C than at 6-8 °C or 12-13 °C for 6-8 days. Compared to non-affected skin, USB-affected tissue had a 7.4% increase in total phenolics concentration. However, polyphenol oxidase (PPO) and peroxidase (POD) activities decreased by 19%. Anatomical similarities were observed between USB symptoms and sapburn caused by spurt sap or terpinolene (a major sap component) to abraded skin areas. Incidence of sapburn was higher in abraded fruit held at 12 °C than at 20 °C.

CONCLUSION

Holding HG mango fruit at 10 °C can intensify USB. Activities of PPO and POD appear not to be regulatory factors in USB expression in HG. Sap components may be involved in USB expression under conducive postharvest conditions. © 2021 Society of Chemical Industry.

Relation between Exercise Performance and Blood Storage Condition and Storage Time in Autologous Blood Doping

Professional athletes are expected to continuously improve their performance, and some might also use illegal methods-e.g., autologous blood doping (ABD)-to achieve improvements. This article applies a systematic literature review to investigate differences in the ABD methods and the related performance and blood parameters owing to different storage conditions-cryopreservation (CP) and cold storage (CS)-and different storage durations. The literature research resulted in 34 original articles. The majority of currently published studies employed CS during ABD. This contrasts to the applied storage technique in professional sports, which was mainly reported to be CP. The second outcome of the literature research revealed large differences in the storage durations applied, which were in the range of one day to 17 weeks between blood sampling and re-infusion, which might affect recovery of the red blood cell mass and thus performance outcome related to ABD. Data revealed that performance parameters were positively affected by ABD when a minimal storage duration of four weeks was adhered. This article identified a need for further research that reflect common ABD practice and its real effects on performance parameters, but also on related blood parameters in order to develop valid and reliable ABD detection methods.

Effects of processing, moisture, and storage length on the fermentation profile, particle size, and ruminal disappearance of reconstituted corn grain

Our objective was to examine the effects of processing, moisture, and anaerobic storage length of reconstituted corn grain (RCG) on the fermentation profile, geometric mean particle size (GMPS), and ruminal dry matter disappearance (DMD). Dry corn kernels were ground (hammer mill, 5-mm screen) or rolled, then rehydrated to 30%, 35%, or 40% moisture, and stored for 0, 14, 30, 60, 90, 120, or 180 d in laboratory silos. Rolled corn had an increased GMPS compared with ground corn (2.24 and 1.13 mm, respectively, at ensiling). However, there was a trend for an interaction between processing and moisture concentration to affect particle size, with GMPS increasing with increased moisture concentration, especially in ground corn. Longer storage periods also slightly increased GMPS. Processing, moisture, and storage length interacted to affect the fermentation pattern (two- or three-way interactions). Overall, pH decreased, whereas lactic acid, acetic acid, ethanol, and NH3-N increased with storage length. RCG with 30% moisture had less lactic acid than corn with 35% and 40% moisture, indicating that fermentation might have been curtailed and also due to the clostridial fermentation that converts lactic acid to butyric acid. Ensiling reconstituted ground corn with 30% of moisture led to greater concentrations of ethanol and butyric acid, resulting in greater DM loss than grain rehydrated to 35% or 40% of moisture. Ammonia-N and in situ ruminal DMD were highest for reconstituted ground corn with 35% or 40% of moisture, mainly after 60 d of storage. Therefore, longer storage periods and greater moisture contents did not offset the negative effect of greater particle size on the in situ ruminal DMD of rolled RCG. Nonetheless, RCG should be ensiled with more than 30% moisture and stored for at least 2 mo to improve the ruminal DMD and reduce the formation of ethanol and butyric acid.

Interactions between Egg Storage Duration and Breeder Age on Selected Egg Quality, Hatching Results, and Chicken Quality

Simple Summary

Egg storage duration and breeder age are two important factors influencing productivity and profitability of hatcheries. These factors probably interact with each other to influence egg quality, apparent fertility, hatchability, and hatchling quality. The aim of this study was to investigate interactions between egg storage duration and broiler breeder age on these parameters. It was demonstrated that eggs from young breeders were the most resistant to storage duration increase in relationship to early and middle embryonic mortality than eggs from older breeders. However, the opposite was found for hatchling quality, where yolk free body mass, which increased from young to old breeders after five days of storage, increased only from middle to old breeders after prolonged storage (19 days). The intestine percentage decreased also after long storage in younger breeders, but in older breeders no significant effect of egg storage duration was found.

Abstract

Egg storage duration and breeder age are probably interacting to influence egg quality, hatchability, and hatchling quality. To evaluate this interaction, the impact of breeder age (31, 42, 66 weeks) and storage duration (2, 5, 12, 19 days) was investigated on broiler breeder eggs (Arbor Acres). Thick albumen diameter and pH increased, and yolk dry matter decreased between 2 and 19 days of storage. With the increase of breeder age from 31 to 66 weeks, albumen height, percentage and dry matter and shell percentage decreased and the egg weight and yolk percentage, dry matter and diameter increased. Prolonged egg storage increased the yolk pH in all breeder ages, but earlier and steeper in the oldest breeders. Prolonged egg storage resulted in a lower hatchability of set and fertile eggs due to a higher percentage of embryonic mortality. Early mortality increased earlier and steeper with prolonged egg storage in the oldest compared to younger breeders. Between 5 and 19 days of storage, yolk free body mass, liver and proventriculus + gizzard percentages decreased, as well as hatchling length and yolk efficiency (yolk absorption per initial yolk weight). The latter effects were most pronounced in the younger than in the older breeders. Therefore, eggs are preferably stored shorter than 7 d, but if long storage (≥12 days) cannot be avoided, we recommend to store eggs of older breeders when egg quality and hatchability are most important. In case hatchling quality is most important, it would be better to store eggs of younger breeders (31 weeks) for a prolonged period.

Effect of drying methods and storage with agro-ecological conditions on phytochemicals and antioxidant activity of fruits: a review

Choice of drying methods significantly impacts the nutritive and non-nutritive compounds in fruits and vegetables. Phytochemicals such as total phenolics and total flavonoids are non-nutritive bioactive compounds and are found in plants which are of important value due to their antioxidant properties in minimizing the oxidation reaction. However, drying and storage conditions and duration significantly affect these important quality attributes. There is currently no review article on the impact of the drying and storage conditions on these quality attributes. Therefore, the aim of this review paper is to investigate the impact of drying methods on these important phytochemicals and their antioxidant activity on dried products during the storage period. Different drying methods cause desirable and undesirable changes to dried products both physically and chemically. It is found that during the drying process at various temperature ranges from 40 to 80 °C, chemical changes occurs which affects the phenolic and the flavonoid content of dried products to increase or decrease. The increase in antioxidant activity after drying is also due to oxidized polyphenols and Maillard reaction products. This results to changes in the antioxidant potential of the dried food product and its impact on the shelf life.

Analysing tropical elasmobranch blood samples in the field: blood stability during storage and validation of the HemoCue® haemoglobin analyser

Blood samples collected from wild-caught fishes can provide important information regarding the effects of capture (and thus post-release survival) as well as other stressors. Unfortunately, blood samples often cannot be analysed immediately upon sampling, and blood parameters (e.g. blood oxygen levels and acid-base parameters) are known to change with storage duration due to the metabolic activity of the red blood cells. We obtained blood samples from both untreated and stressed individuals of both blacktip reef shark (Carcharhinus melanopterus) and sicklefin lemon shark (Negaprion acutidens) to determine the effects of storage duration on blood pH, haematocrit and haemoglobin concentration ([Hb]). We found no significant effects after storage on ice for up to 180 minutes. Moreover, to validate the usability of a HemoCue haemoglobin analyser (a point-of-care device), we compared data from this device to [Hb] determined using the cyanomethaemoglobin method with blood samples from 10 individuals from each of the aforementioned species as well as epaulette shark (Hemiscyllium ocellatum). Values from the HemoCue consistently overestimated [Hb], and we therefore developed the necessary correction equations. The correction equations were not statistically different among the three elasmobranch species within the biologically relevant range but did differ from published corrections developed using blood from temperate teleost fishes. Although the HemoCue is useful in field situations, development of species-specific calibration equations may be necessary to ensure the reliability of inter-species comparisons of blood [Hb]. Together, these data should increase confidence in haematological stress indicators in elasmobranch fishes, measurements of which are critical for understanding the impact of anthropogenic stressors on these ecologically important species.

Quality and oxidative stability of eggs laid by hens fed marigold extract supplemented diet

The research objective was to determine the influence of marigold extract and storage duration on the indicators of egg quality and on the oxidative stability of eggs. The 5-wk long research was carried out on 300 laying hens. Laying hens were divided into control group (C-without marigold extract supplementation) and 2 experimental groups (E1-supplemented 1 g/kg of marigold extract and E2-supplemented 2 g/kg of marigold extract to diet). The eggs were analyzed on 2 occasions, as fresh eggs (1 D after collecting in the facility) and after 28 D of storage in a refrigerator on +4°C. On both occasions, there were 30 eggs analyzed per each group. Statistical analysis of the research results proved influence of marigold extract supplementation and storage duration on the weight of eggs (P < 0.05) and on the eggshell thickness (P < 0.001), but they did not have any influence on other indicators of external egg quality. Storage duration affected (P < 0.001) all indicators of internal egg quality, whereas supplementation of marigold extract influenced (P < 0.001) only the pH value of yolk. Supplementation of marigold extract influenced (P < 0.001) the yolk color intensity. There was a significant increase in the value of yolk color, starting with 9.63 in the C group and raising to 12.77 (E1) and 13.50 (E2) in fresh eggs. Yolk color of stored eggs was more intensive than the yolk color of fresh eggs in all 3 groups (P < 0.001). Supplemented marigold extract did not influence the obtained results of lipid oxidation in yolks, whereas storage duration had influence (P < 0.05) on oxidation intensity. The most favorable value of oxidation in fresh eggs was determined in the E2 group (0.545 μg MDA/g), and in stored eggs in the E1 group (0.615 μg MDA/g). Based on the research results, it was concluded that the supplementation of marigold extract had favorable influence on the yolk color intensity and on the oxidative stability of eggs without having negative influence on other egg quality indicators.

Stability of plasma proteins and factors in Chinese universal pooled plasma

Objective

This study aimed to determine the precision dose of Chinese universal pooled plasma (CUPP) developed by our laboratory, and the stability of plasma proteins and factors.

Methods

A total of 100 single fresh-frozen plasma (FFP) units were selected to test plasma proteins, including total protein, albumin, fibrinogen, factor V, factor VIII, antithrombin-III, and protein C. Different pooling protocols with 20, 40, 60, 80, and 100 units were used to optimize the number of pooled units. The pooled plasma was then used to further evaluate the optimal storage conditions and duration at 22°C, 4°C, and −20°C.

Results

There were considerable differences in plasma protein levels among single units of FFP. After different pooling protocols, the mean value of plasma proteins did not significantly change. However, with a larger number of pooled samples, plasma proteins were more stable with a smaller standard deviation. Acceptable storage for CUPP was achieved with storage for 1 day at 22°C, 4 days at 4°C, and 3 months at −20°C.

Conclusion

A uniform level of plasma proteins and factors in CUPP appears to support establishment of a precise dose of plasma.

[Storage and Reactivation of Anaerobic Ammonium Oxidation (ANAMMOX) Sludge at Room Temperature]

Slow growth rates limit the widespread application of anaerobic ammonia oxidation (ANAMMOX) reactions, which presents a need for the study of long-term storage and rapid reactivation of ANAMMOX sludge. Under room temperature conditions (14~30℃), this study investigated the effects of storage duration on the residual activity and the activity after reactivation of ANAMMOX sludge without the addition of external substances. The chosen storage durations were 15, 30, 45, 60, 75 and 100 days, respectively. The results show that the residual specific ANAMMOX activities (SAAs) of the stored ANAMMOX sludge were 90.9%, 64.3%, 61.7%, 43.2%, 25.8% and 19.3% of the initial activity (activity before sludge storage) after 15, 30, 45, 60, 75 and 100 days, respectively. Therefore, the residual SAA decreases linearly with an increase in the storage duration of ANAMMOX sludge (R² was 0.978). The SAAs after reactivation with a storage duration of 15, 30, 45, 60 and 75 days were all higher than the initial SAA and reached 103.4%, 129.3%, 124.8%, 111.7% and 116.9% of the initial SAA before its storage, respectively. However, the SAA after reactivation after storage for 100 days was just 98.9% of the initial SAA. In conclusion, after as long as 100 days of storage duration under room temperature, the residual SAA of ANAMMOX sludge decreases to 0.0513 g·(g·d)^-1, and its ANAMMOX activity can still be recovered after 9.5 days of reactivation culture.

Red blood cell storage duration and long-term mortality in patients undergoing cardiac intervention: a Danish register study

OBJECTIVES

To study the effect of red blood cell (RBC) storage duration on long-term mortality in patients undergoing cardiac intervention.

BACKGROUND

RBCs undergo numerous structural and functional changes during storage. Observational studies have assessed the association between RBC storage duration and patient outcomes with conflicting results.

METHODS

Between January 2006 and December 2014, 82 408 patients underwent coronary angiography. Of these, 1856 patients received one to four RBC units within 30 days after this procedure. Patients were allocated according to length of RBC storage duration: short-term (≤11 days), intermediate (IM)-term (12-23 days) and long-term (≥24 days). The study endpoints were 30-day and long-term all-cause mortality.

RESULTS

A total of 4168 RBC units were given to 1856 patients. The mean RBC storage duration was 8.5 ± 2.1, 17.7 ± 3.4 and 29.9 ± 3.4 days in the short-term, IM-term and long-term storage groups, respectively. There was no difference in baseline characteristics between the groups. The long-term storage group received significantly more units (2.4 ± 1.0 units) as compared to the short-term (2.0 ± 1.0 units; P < 0.001) and IM-term storage group (2.2 ± 1.0 units; P < 0.01). In the survival analysis, there was no significant difference in all-cause mortality between the groups (log-rank: 0.509 for 30-days mortality; 0.493 for 5-year mortality). Additional stratified analysis demonstrated no association between RBC storage duration and long-term mortality.

CONCLUSION

This study did not find an association between RBC storage duration and 30-days or long-term mortality in patients undergoing cardiac intervention.

Antioxidant response and related gene expression in aged oat seed

To evaluate deterioration of oat seeds during storage, we analyzed oxygen radicals, antioxidant enzyme activity, proline content, and gene transcript levels in oat seeds with different moisture contents (MCs; 4, 16, and 28% w/w) during storage for 0, 6, and 12 months (CK, LT-6, and LT-12 treatments, respectively) at 4°C. The germination percentage decreased significantly with higher seed MCs and longer storage duration. The concentrations of superoxide radical and hydrogen peroxide increased with seed MC increasing. The activities of catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) may have had a complementary or interacting role to scavenge reactive oxygen species. As the storage duration extended, the proline content decreased in seeds with 4 and 16% MC and increased in 28%. These findings suggest that proline played the main role in adaptation to oxidative stress in seeds with higher MC (28%), while antioxidant enzymes played the main role in seeds with lower MCs (4%, 16%). In the gene transcript analyses, SOD1 transcript levels were not consistent with total SOD activity. The transcript levels of APX1 and CAT1 showed similar trends to those of APX and CAT activity. The transcript levels of P5CS1, which encodes a proline biosynthetic enzyme, increased with seed MC increasing in CK. Compared with changing of proline content in seeds stored 12 months, PDH1 transcript levels showed the opposite trend and maintained the lower levels in seeds of 16 and 28% MCs. The transcript level of P5CS1 was significantly affected by MC, and PDH1 could improve stress resistance for seed aging and maintain seed vigor during long-term storage.