Total Free Amino Acid Content Research Articles

Application of Pyroligneous Acid as a Plant Growth Stimulant Can Improve the Nutritional Value of Soybean Seed

Farmers today are using biochemical treatments to improve their crop yields. Commercialized organic biostimulants exist in the form of pyroligneous acid generated by burning agricultural waste products. During the 2023 growing season, we demonstrated that soil treatment with a commercial pyroligneous acid product, Coriphol™, manufactured by Corigin Solutions, Inc., stimulated plant growth and significantly improved yield with an optimal treatment dose of 2 gal. acre−1. In the present work, we examined the effect of this treatment on soybean nutritional content using seed harvested from the 2023 season. Total mean seed protein content for untreated control plants was 32.26 ± 0.49% of dry mass and increased 10.8% to 35.64 ± 0.64% with treatment. This increase resulted in a net reduction in total free amino acid content, although levels of the essential dietary amino acid, lysine, were boosted 6-fold. Total lipid content was unaffected by treatment with mean levels of 21.61 ± 0.70% of dry mass noted. Treatment, however, reduced saturated fatty acid content by roughly 40%, and reduced the polyunsaturated content of linoleic acid in favor of the monounsaturated fatty acid, oleic acid. Finally, Coriphol™ treatment did not impact seed content of eight essential micronutrients including Na, Mg, K, Ca, Fe, Ni, Cu, and Mo, but did significantly boost Zn and Mn levels. Altogether, these results demonstrate that soil treatment with the growth stimulant Coriphol™ has the potential to improve the dietary nutritional value of soybean.

Biochemical and molecular responses to long-term salinity challenges in northern quahogs Mercenaria mercenaria

Salinity is a key environmental factor for aquatic organisms for survival, development, distribution, and physiological performance. Salinity fluctuation occurs often in estuary and coastal zones due to weather, tide, and freshwater inflow and thus heavily affects coastal marine aquaculture. The northern quahog Mercenaria mercenaria is an important aquaculture species along the Atlantic coast in the US, but information on the effects of salinity stress on physiological, immunological, and molecular responses is still scarce. The goal of this study was to investigate cellular and molecular responses through challenges of long-term hypo- and hyper-salinities in northern quahogs. The objectives were to: 1) measure the survival of market-sized quahogs under a three-month salinity challenge at 15 (hyposalinity), 25 (control), and 35 ppt (hypersalinity); 2) determine cellular changes of hemocytes through analysis of immune functions; 3) determine changes of the total free amino acid concentration in gills, and 4) evaluate the molecular responses in gills using RNAseq technology with qPCR verification. After a three-month salinity challenge, no mortality was observed, and increases in body weight were identified with a significantly higher increase in the hypersalinity group. Northern quahogs equilibrated their hemolymph osmolality with the ambient seawater and were verified to be osmoconformers. Significant differences were observed in total hemocyte concentration, lysosomal presence, ROS production, and phagocytic rate, but no differences were found in cell viability. The total free amino acid concentration within gills was positively correlated to water salinity, indicating amino acids were critical organic osmolytes. The transcriptome of gills using RNAseq revealed differential expression genes (DEG) encoding amino acid transporters (SLC6A3, SLC6A6, SLC6A13, SLC25A38), ion channel proteins (T38B1, GluCl, ATP2C1), and water channel protein (AQP8) in hyposalinity or/and hypersalinity groups, indicating these genes play critical roles in intracellular isosmotic regulation. Overall, the findings in this study provided new insights into osmoregulation in northern quahogs.

Comprehensive analysis of flavor compounds and metabolites of vinasse hairtail fermentation based on GC-IMS and untargeted-based metabolomics

This study focused on investigating the degradation of proteins, metabolites, and flavors during the fermentation of vinasse hairtail, a local specialty fermented food in Zhoushan, China. The whole-protein SDS-PAGE results showed significant degradation of proteins, particularly actin and myosin. Total free amino acid content significantly increased, glutamate, leucine, alanine, and lysine were identified as the primary flavor amino acids conducive to the flavor, with umami, sweet, and bitter amino acids being predominant. The volatile constituents of the vinasse hairtail samples collected before fermentation (0 days) and after fermentation (8 days) were examined using gas chromatography-ion mobility spectrometry (GC-IMS). It revealed a total of 83 volatile flavor compounds, with the relative content of esters increasing and alcohols decreasing during fermentation. The untargeted metabolomics analysis identified 395 unique metabolites; the top 100 metabolites exhibited significant differences, including 52 oligopeptides, 18 organic acids and their derivatives, and 12 lipids and lipid molecules. The metabolic pathways involved in N-glycan biosynthesis, taurine and hypotaurine metabolism, pyrimidine metabolism, glycerophospholipid metabolism, alanine, aspartic acid, and glutamic acid metabolism, tricarboxylic acid cycle, and histidine metabolism. These pathways contribute to the generation of amino acids, sugars, organic acids, and other flavor compounds, ultimately influencing the evolution of the flavor of vinasse hairtail.

Physiological, genetical changes and cdc2 gene expression for osmotic stressed Vicia faba reveal the alleviation effect of gamma radiation and putrescine

Climate change caused increasing in soil salinity worldwide. Therefore, it is critical to enhance the capability of plant to tolerate salinity stress. For this goal, putrescine and irradiation by gamma radiation were used to improve the salt tolerance of Vicia faba (the most important human crop). The results indicated depression in mitotic division and all growth parameters associated with the induction of micronucleus (MN) when salinity increased to 100mM, while there was increase in mitotic aberrations. NaCl decreased total soluble sugar, while total N%, total free amino acid, proline and protein contents showed slight increase with increasing salinity stress. Putrescine and gamma radiation mitigated the effect of salinity on cell division and growth parameters. Salt stress decreased the expression of gene encoding cyclin-dependent kinase 2 (cdc2). Both putrescine and gamma radiation increased cdc2 expression. The genetic diversity has been detected among control and treated V. faba using ISSR and SCoT markers. Ten primers had successfully generated 129 reproducible polymorphic amplicons that were suitable for studying the genetic diversity between studied genotypes. ISSR markers provided more discriminating data and were more informative than SCoT markers. Besides, cluster analysis using UPGMA and PAC successfully explained the genetic diversity within studied genotypes. These findings emphasize the efficiency of putrescine and gamma radiation for alleviating the negative impact of salt stress. Moreover, prove the importance of assessing mitotic activity, chromosomes behavior, physiological parameters, the expression level of cdc2 and molecular diversity in V. faba under stress to improve the salt tolerance of it.

Gamma amino butyric acid (GABA) application modulated the morpho-physiological and yield traits of fragrant rice under well-watered and drought conditions

BackgroundChanging climate is causing erratic rainfall and prolonged drought periods, thus posing serious threats to crop productivity. Owing to severity of drought events, it is imperative to take proactive measures to enhance the resilience of drought sensitive crops like rice. Therefore, the present study was carried out to improve the drought stress tolerance in rice through gamma amino butyric acid (GABA) application.MethodsThe experiment was included four GABA concentrations i.e., 0 mM as control, 1 mM, 1.5 mM, and 2 mM, two water levels i.e., 100% and 50% field capacity (referred as FC100 for well-watered and FC50 for drought conditions, respectively), and two fragrant rice cultivars i.e., Super Basmati and Basmati-515.ResultsThe findings unveiled a comprehensive improvement in various parameters with GABA application in fragrant rice under both well-watered (FC100) and water-limited (FC50) conditions, compared to the control. Specifically, GABA induced enhancements were observed in plant height, root length, fresh weight, dry weight, total soluble protein content, and total free amino acid content across both cultivars. Moreover, GABA application significantly improved peroxidase (POD) and catalase (CAT) enzyme activities, alongside elevating anthocyanin levels, while concurrently reducing H2O2 contents in both FC100 and FC50 treatments. Furthermore, the positive impact of GABA extended to morphological traits, with notable increases in panicle length, total tillers and productive tillers per hill, branch and grain numbers per panicle, and 1000-grain weight for Super Basmati and Basmati 515 cultivars under both water regimes, compared to Ck. Similarly, the grain yield increased by 31.01% and 27.32% under FC100 and 36.85% and 27.71% under FC50 in Super Basmati and Basmati-515, respectively, in response to GABA application, compared to Ck. Additionally, principal component analysis (PCA) revealed significant variances attributed to Dim1 and Dim2, with 86.1% and 4.0% of the variance, respectively, across three bi-plots encompassing rice cultivars, water levels, and GABA treatments. Notably, all tested indices, except for H2O2 and non-productive tillers per hill, exhibited positive correlations amongst themselves and with rice yield, further emphasizing the beneficial effects of GABA application on fragrant rice under well-watered and drought conditions.ConclusionsGABA significantly improved fragrant rice performance under both well-watered (FC100) and water-limited (FC50) conditions. Moreover, integrating GABA application into rice cultivation practices could not only improve the crop resilience to drought stress but also potentially benefiting the future food and nutritional security globally. However, however; further research is needed to understand the cellular and molecular mechanisms of the functionality of GABA in fragrant rice, particularly under drought conditions.

Effects of different drying methods on physicochemical, textural, flavor, and sensory characteristics of yak jerky

The work aimed to study the effect of four drying methods, namely constant temperature hot air drying (HD), microwave drying (MD), hot air microwave drying (HMD), and gradient hot air drying (GHD), on quality characteristics of dried yak meat. The analyses of physicochemical, textural, flavor, and sensory characteristics were carried out based on these four drying methods. The results revealed that microwave dried yak jerky exhibited better color and received the highest sensory score. Hardness of samples were affected by the drying methods, which showed significant differences. There were 21 free amino acids (FAAs) detected in dried yak samples. The samples treated by microwave drying showed the highest total free amino acid content (73.30 mg/100 g) and the EUC value was significantly higher than other methods, indicating the sample displayed greater flavor. A total of 153 volatile compounds were identified in dried yak meat samples, primarily including aldehydes, ketones, and esters. Moreover, the sensory evaluation indicated that the drying methods could significantly affect on color, flavor, and overall acceptability of different samples. Microwave drying samples scored higher than other drying methods. Overall, considering aspects of quality, time savings, and energy efficiency, microwave drying of yak jerky emerges as a more satisfactory option. This study could provide important theoretical support for the application of drying methods to improve the quality of yak jerky and enhance production efficiency.

Unraveling the effect of drought and heat stresses on grain quality of wheat (Triticum aestivum)

Drought stress (DS) and heat stress (HS) have adverse effects on wheat (Triticum aestivum L.) growth, serving as the primary constraints that significantly limit grain yield. Present study was carried out during 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to evaluate the effects of drought and heat stress on grain quality parameters of 4 contrasting wheat genotypes. Several physiological and biochemical parameters were analyzed in wheat cv. C306 (thermotolerant), HD3271 (thermosusceptible), H11500 (drought tolerant) and HD3226 (drought susceptible) under DS and HS. Our study found that disintegration of chlorophyll pigments was higher in wheat cv. HD3226 (43%) under combined stress. Grain weight per spike was reduced by 30% in C306 and 47.3% in HD 3271 under combined drought and heat stress treatment. All cultivars showed reduction in starch, amylose, amylopectin, AGPase and Soluble starch synthase activity under DS and HS. Additionally, a significant increase in total soluble protein and free amino acid content were observed in all genotypes under combined stress. Chlorophyll content and grain weight per spike were positively correlated with the starch, amylose, amylopectin, soluble starch synthase and AGPase activity, while negatively related to the total soluble protein and free amino acid content. The tolerant genotypes maintained higher chlorophyll content, grain weight per spike, starch, amylose, amylopectin, soluble starch synthase and AGPase activity could be used for breeding, for the adaptation to drought and heat under climate change.

Multicontamination Toxicity Evaluation in the Model Plant Lactuca sativa L.

Many contaminated soils contain several toxic elements (TEs) in elevated contents, and plant-TE interactions can differ from single TE contamination. Therefore, this study investigated the impact of combined contamination (As, Cd, Pb, Zn) on the physiological and metabolic processes of lettuce. After 45 days of exposure, TE excess in soil resulted in the inhibition of root and leaf biomass by 40 and 48%, respectively. Oxidative stress by TE accumulation was indicated by markers-malondialdehyde and 5-methylcytosine-and visible symptoms of toxicity (leaf chlorosis, root browning) and morpho-anatomical changes, which were related to the change in water regime (water potential decrease). An analysis of free amino acids (AAs) indicated that TEs disturbed N and C metabolism, especially in leaves, increasing the total content of free AAs and their families. Stress-induced senescence by TEs suggested changes in gas exchange parameters (increase in transpiration rate, stomatal conductance, and intercellular CO2 concentration), photosynthetic pigments (decrease in chlorophylls and carotenoids), a decrease in water use efficiency, and the maximum quantum yield of photosystem II. These results confirmed that the toxicity of combined contamination significantly affected the processes of lettuce by damaging the antioxidant system and expressing higher leaf sensitivity to TE multicontamination.

Potential of Subcritical Water Hydrolysis to Valorize Low-Valued Ray-Finned Fish (Labeobarbus nedgia): Effects of Hydrolysis Temperature and Pressurization Agent.

Subcritical water (SCW) hydrolysis was applied to valorize the low-valued ray-finned fish (Labeobarbus nedgia) into valuable protein hydrolysates, employing N2 and CO2 as pressurization agents at varying temperatures (140, 160, 180, and 200 °C). The degree of hydrolysis (DH) and total free amino acid content increased with temperature for both pressurizing agents. The highest DH (54.5 ± 0.4%) and total free amino acid content (210 ± 1 mg/gprot) were observed at 200 °C when CO2 gas was used as the pressurizing agent. Predominantly, glycine and alanine were released for both pressurizing agents. The antioxidant activity, evaluated through three different assays, increased with temperature and was found to be the highest at 200 °C. This study illustrated the advantages of the intensified SCW technology by using CO2 as a pressurization agent in valorizing low-valued ray-finned fish (Labeobarbus nedgia), as animal residue rich in proteins, for the production of valuable protein hydrolysates with a high fraction of valuable free amino acids, which could offer potential applications as a functional ingredient in the food industry.

Study on the Digestion-Induced Changes in the Characteristics and Bioactivity of Korean Native and Overseas Cattle-Derived Peptides.

This study was conducted to compare and analyze the changes in the biochemical characteristics and biological activity of peptide extracts derived from Chickso, Hanwoo, and Wagyu beef during digestion. The results of the in vitro digestion analysis revealed that the digestion rate, total free amino acid content, and antioxidant and antihypertensive activities of Chickso loin and shank myofibrillar proteins were significantly higher (p<0.05) than those of Hanwoo and Wagyu loin and shank myofibrillar proteins. Particularly, the peptide extracts of Chickso loin and shank had a high angiotensin-converting enzyme inhibitory activity. In mice in vivo digestion experiment, the blood serum of mice fed with Chickso loin peptide extract (<10 kDa) showed the highest antioxidant enzyme activity. Thus, Chickso peptide extracts were deemed to be similar or more bioactive than Hanwoo and Wagyu peptide extracts, and can be used as bioactive materials.

Effect of ultrasound‐assisted osmotic dehydration on the drying characteristics and quality properties of goji

AbstractThe waxy layer on the surface of the goji fruit increases the dehydration time. In this study, the novel use of ultrasound pretreatment (10, 20, and 30 min) assisted with osmotic dehydration was utilized to improve drying efficiency and product quality of goji. The results showed that goji treated with ultrasound‐assisted osmotic dehydration lost more water and gained more solids during osmotic dehydration than goji treated with osmotic dehydration only. Furthermore, the ultrasound‐assisted osmotic dehydration pretreatment method shortened the drying time for freezing drying goji and lowered the water activity of the dried goji. This may be due to the destruction of the wax layer on the surface of the goji by ultrasound. The rehydration rate of the goji treated with ultrasound for 20 min was significantly higher than that of the samples dried by osmosis dehydration only. The application of ultrasound‐assisted osmotic dehydration resulted in the best color and the highest glutathione and total free amino acid content of goji, especially the taurine. Besides the above, the antioxidant capacity of ultrasound‐assisted osmotic dehydration‐treated goji was enhanced, with the highest 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging capacity and ferric reducing antioxidant power (FRAP) values for the samples in the 20‐min ultrasound‐assisted group. The results demonstrate that ultrasound‐assisted osmotic dehydration not only reduces the drying time of goji but also enhances its product quality.Practical applicationsThis study explored the effects of different ultrasound‐assisted osmotic dehydration methods on the drying efficiency and quality of freeze‐dried goji. The findings provide a scientific basis for improving goji drying engineering and offer a potential strategy for enhancing goji quality.

Characterization of Yeast Protein Hydrolysate for Potential Application as a Feed Additive.

Yeast protein can be a nutritionally suitable auxiliary protein source in livestock food. The breakdown of proteins and thereby generating high-quality peptide, typically provides nutritional benefits. Enzyme hydrolysis has been effectively uesed to generate peptides; however, studies on the potential applications of different types of enzymes to produce yeast protein hydrolysates remain limited. This study investigated the effects of endo- (alcalase and neutrase) and exotype (flavourzyme and prozyme 2000P) enzyme treatments on yeast protein. Endotype enzymes facilitate a higher hydrolysis efficiency in yeast proteins than exotype enzymes. The highest degree of hydrolysis was observed for the protein treated with neutrase, which was followed by alcalase, prozyme 2000P, and flavourzyme. Furthermore, endotype enzyme treated proteins exhibited higher solubility than their exotype counterparts. Notably, the more uniform particle size distribution was observed in endotype treated yeast protein. Moreover, compared with the original yeast protein, the enzymatic protein hydrolysates possessed a higher content of β-sheets structures, indicating their higher structural stability. Regardless of enzyme type, enzyme treated protein possessed a higher total free amino acid content including essential amino acids. Therefore, this study provides significant insights into the production of protein hydrolysates as an alternative protein material.

Changes and dynamics of the main quality components in tea leaves of 4 tea cultivars during the shading process

The purpose of this study was to analyze the relationship between different shading conditions, picking time for main quality components of tea. The main quality components of 4 tea cultivars [Camellia sinensis (L.) O. Kuntze], including the separated tea shoot tissues (leaves, buds, stems), under 4 shading rates during the traditional 20-day shading period were examined. Results showed the Chlorophyll contents after 12 days of shading treatment were significantly higher than control, but after that it ceased increasing significantly Initially, the theanine, total free amino acid, caffeine, and tea polyphenol contents showed decreased trend but then leveled off after 12 days. The increase of free amino acids, caffeine, chlorophyll and the decrease of tea polyphenols induced by shading were mainly determined by shading level and tenderness. Meanwhile, shading changed the proportion of main quality components in tea leaves and stems, long-term shading does not promote high quality matcha. All of the results indicated the quality of matcha with grade 1 could be produced by shading rate of 80 % and shading for 12 days. Appropriate shading time and shading rate are beneficial to improve the quality of Matcha.

Effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets

BackgroundPromoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization. The rational allocation of dietary starch sources and the exploration of appropriate dietary glucose release kinetics may promote the dynamic balance of dietary glucose and amino acid supplies. However, research on the effects of diets with different glucose release kinetic profiles on amino acid absorption and portal amino acid appearance in piglets is limited. This study aimed to investigate the effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets.MethodsSixty-four barrows (15.00 ± 1.12 kg) were randomly allotted to 4 groups and fed diets formulated with starch from corn, corn/barley, corn/sorghum, or corn/cassava combinations (diets were coded A, B, C, or D respectively). Protein retention, the concentrations of portal amino acid and glucose, and the relative expression of amino acid and glucose transporter mRNAs were investigated. In vitro digestion was used to compare the dietary glucose release profiles.ResultsFour piglet diets with different glucose release kinetics were constructed by adjusting starch sources. The in vivo appearance dynamics of portal glucose were consistent with those of in vitro dietary glucose release kinetics. Total nitrogen excretion was reduced in the piglets in group B, while apparent nitrogen digestibility and nitrogen retention increased (P < 0.05). Regardless of the time (2 h or 4 h after morning feeding), the portal total free amino acids content and contents of some individual amino acids (Thr, Glu, Gly, Ala, and Ile) of the piglets in group B were significantly higher than those in groups A, C, and D (P < 0.05). Cluster analysis showed that different glucose release kinetic patterns resulted in different portal amino acid patterns in piglets, which decreased gradually with the extension of feeding time. The portal His/Phe, Pro/Glu, Leu/Val, Lys/Met, Tyr/Ile and Ala/Gly appeared higher similarity among the diet treatments. In the anterior jejunum, the glucose transporter SGLT1 was significantly positively correlated with the amino acid transporters B0AT1, EAAC1, and CAT1.ConclusionsRational allocation of starch resources could regulate dietary glucose release kinetics. In the present study, group B (corn/barley) diet exhibited a better glucose release kinetic pattern than the other groups, which could affect the portal amino acid contents and patterns by regulating the expression of amino acid transporters in the small intestine, thereby promoting nitrogen deposition in the body, and improving the utilization efficiency of dietary nitrogen.

The Effects of Brassinosteroids on Nitrogen Utilization in Rice

Nitrogen and brassinosteroids (BRs) play a vital role in modulating the growth, development, and yield of rice. However, the influences of BRs on nitrogen assimilation and metabolism in rice are not fully understood. In this study, we analyzed the impact of BRs on nitrogen utilization in rice using the indica variety ‘Zhongjiazao 17’ and the japonica variety ‘Nipponbare’ in hydroponic conditions. The results showed that BR treatment could efficiently elevate nitrate and ammonium nitrogen accumulation in both shoots and roots. Furthermore, some genes involved in the uptake of nitrate and ammonium in roots were stimulated by BRs, though we noted subtle variances between the two rice cultivars. Moreover, BRs augmented the activity of nitrate reductase (NR) and glutamine synthetase (GS) in roots, along with NR in shoots. Interestingly, BRs also spiked the total free amino acid content in both the shoots and roots. Gene expression analysis uncovered a robust induction by BRs of NR genes and GS-related genes in the roots of both ‘Nipponbare’ and ‘Zhongjiazao 17’. Collectively, our data suggest that BRs significantly enhance the accumulation of both nitrate and ammonium in rice and trigger a series of reactions related to nitrogen utilization.

The impact of processing technology on microbial community composition and functional properties of Beninese maize ogi

Traditionally fermented maize starch, called ogi, is produced to prepare akpan, a yoghurt-like street food widely consumed in Benin. Current maize ogi production practices were compared to assess the impact of different processing technologies on the characteristics of the fermented product as a basis to determine best practices. Maize starch slurry samples were collected from processors in five municipalities in southern Benin and analysed before fermentation (starch samples) and after spontaneous fermentation (ogi samples). Four technological pathways for maize starch production were distinguished based on variations in the duration of steeping the grains, which ranged from 6 to 72 h, and whether or not kneading of the wet flour before filtration was practised. Six categories of maize ogi were derived from the four technology groups based on the duration of the fermentation, which lasted from 6 to 24 h. The average pH of maize starch varied from 3.2 to 5.3, with the lowest values for the two technology groups that also had the highest lactate concentrations (9–11.8 g/L). The six maize ogi categories had a pH ranging from 3.1 to 4.0. Viable plate counts of lactic acid bacteria were similar for maize starch samples and for ogi samples, whereas yeast counts showed clear differences. Members of the genera Limosilactobacillus, Lactobacillus, Weissella, Streptococcus and Ligilactobacillus, dominated the bacterial community in maize starch, and were also dominant in maize ogi. The members of the genera dominating the fungal community in maize starch were also dominant in maize ogi, except for Aspergillus and Stenocarpella spp., which decreased in relative abundance by fermentation. The highest total free essential amino acid concentration was 61.6 mg/L in maize starch and 98.7 mg/L in ogi. The main volatile organic compounds in maize starch samples were alcohols, esters, and carboxylic acids, which also prevailed in maize ogi samples. The results indicate that the characteristics of traditional maize ogi depend on the processing technologies used to produce the maize starch before the intentional fermentation into ogi, with no clear-cut connection with the production practices due to high variations between samples from the same technology groups. This revealed the importance of a standardized maize starch production process, which would benefit controlling the starch fermentation and the characteristics of maize ogi. Further research is needed to understand the hidden fermentation during maize starch production for determination of the best practices that support the production of quality maize ogi.

Effects of soybean cultivar and starter strain on biogenic amines formation during Cheonggukjang fermentation

Cheonggukjang, a traditional Korean fermented seasoning, contains biogenic amines (BAs). This research aimed to explore the effects of soybean cultivar, strain, and temperature on BAs formation during Cheonggukjang fermentation. Moisture, pH, total aerobic plate count, and protease activity were measured. Free amino acids (FAAs) and BAs were determined by high-performance liquid chromatography. Total FAA and BA contents tended to increase with fermentation time. Total BAs in the samples initially ranged from 112.65 to 153.05 mg/kg and ultimately increased to 155.72–614.28 mg/kg at 25 °C and 201.95–738.39 mg/kg at 37 °C, respectively. Bacillus licheniformis-inoculated samples had the highest total BA content (over 400 mg/kg) after 96 h of fermentation. Final histamine content in cv. ‘Somoktae’-made samples generally exceeded that in samples produced by the other two cultivars. These findings indicate that soybean cultivar, strain, and fermentation temperature all play pivotal roles in controlling the contents of BAs in Cheonggukjang.

Effects of Dietary Eucommia ulmoides Leaf Extract Supplementation on Growth Performance, Meat Quality, Antioxidant Capacity, and Lipid Metabolism of Finishing Pigs.

This study aimed to investigate the effects of dietary Eucommia ulmoides leaf extract (ELE) on meat quality, antioxidant capacity, and lipid metabolism in finishing pigs. A total of 240 "Duroc × Landrace × Yorkshire" crossbred pigs with an initial weight of 74.70 ± 0.77 kg were randomly assigned to two groups: control group and 0.2% ELE group, with each group containing 10 replicates of 12 pigs per pen (half barrows and half gilts). The data showed dietary 0.2% ELE supplementation did not affect growth performance but tended to reduce the backfat thickness of the finishing pigs (p = 0.07). ELE diets increased pH value (p < 0.05) and meat color score (p = 0.01) and decreased 45 min L* value (p < 0.05), 24 h L* value (p = 0.01), pressurization loss (p = 0.01), and 24 h drip loss (p < 0.05) in longissimus dorsi (LD) muscle, accompanied by an increased (p < 0.05) proportion of monounsaturated fatty acids (MUFA) and decreased polyunsaturated fatty acids (PUFA) (p = 0.06) and n-6/n-3 PUFA ratio (p = 0.05) compared to controls. In addition, ELE supplementation increased inosine monophosphate (IMP) (p = 0.01), sweet amino acids (AAs) (p < 0.05), and total free AA content (p = 0.05) in LD. Meanwhile, increased activity of glutathione peroxidase (p < 0.05) and superoxide dismutase (p < 0.01) in both serum and LD muscle and decreased malondialdehyde content (p < 0.01) in LD muscle were detected with ELE treatment. Moreover, pigs fed ELE had a higher total protein (p < 0.01), albumin (p < 0.05), and high-density lipoprotein cholesterol (p < 0.05) and a lower total cholesterol (p < 0.01) and triacylglycerols (p = 0.06) in serum. Consistently, significant effects of dietary ELE were observed on the relative mRNA expression of lipid metabolism in the backfat and the LD muscle, respectively. ELE attenuated lipogenic processes in backfat, decreasing the relative expression of acetyl-CoA carboxylase and upregulating the relative expression of adipose triacyl glyceride lipase, carnitine palmitoyl transferase 1B, and fatty acid-binding protein 4 (p < 0.05). ELE also decreased the relative expression of CCAAT/enhancer-binding protein α (p < 0.05), fatty acid translocase (p < 0.05), carnitine palmitoyl transferase 1B (p < 0.01), and adipose triacyl glyceride lipase (p < 0.05) in LD muscle (p < 0.05). More specifically, lipogenesis appeared to be inhibited in both LD muscle and backfat, with the difference being that lipolysis was enhanced in backfat and inhibited in LD muscle. In conclusion, dietary ELE supplementation can potentially enhance carcass traits, sensory quality, and nutritional value of pork without negatively affecting intramuscular fat content. The underlying mechanism for these positive effects may be linked to the alterations in lipid metabolism and increased antioxidant capacity induced by ELE.

The Biochemical Composition and Quality of Adult Chinese Mitten Crab Eriocheir sinensis Reared in Carbonate-Alkalinity Water

Saline–alkaline aquaculture has become an important breakthrough in expanding the space available for aquaculture in China. However, the biochemical composition and quality of Eriocheir sinensis reared in carbonate alkalinity water are still unclear. Therefore, this study investigated the edible yield, coloration, and nutritional and flavor quality of Eriocheir sinensis. A significantly lower gonadosomatic index (GSI), meat yield (MY), and total edible yield (TEY) were detected in intensive pond (IP) samples than those in semi-intensive reed wetland (SIWR) (p &lt; 0.05). Six color parameters in the hepatopancreas (p &lt; 0.05) differed between IP and SIRW. The contents of crude protein and fat in the female hepatopancreas of IP were significantly higher than those in SIRW (p &lt; 0.05). The concentrations of total monounsaturated fatty acids (∑MUFA), total essential fatty acids (∑EFA), and hypocholesterolaemic/hypercholesterolaemic ratio (h/H) in the female edible tissues checked were higher in IP than those in SIRW, with significant differences including ∑MUFA in the hepatopancreas and ovary, ∑EFA in the muscle, and h/H in the ovary (p &lt; 0.05). Higher total free amino acid (∑FAA) contents of muscle were detected in SIRW than that in IP samples. Significantly higher K, Ca, Mg, Fe, and Zn contents in the ovary were detected in SIRW samples compared to IP (p &lt; 0.05). Overall, Eriocheir sinensis reared in carbonate-alkalinity water is an important source of nutrients.

Investigation of stimulated growth effect by application of L-aspartic acid on poplar

Poplar is an important resource for the production of wood-based products. L-aspartic acid (Asp) is a proteinogenesis amino acid that plays a critical role in cell growth modulation and stress response. Also, Asp is widespread in the commonly used amino acid-based biostimulant products. However, its effects on poplars remain largely unknown. To address this issue, we applied different concentrations of Asp to poplar seedlings under N reduction conditions (simulating low N availability status), and assessed the effects of Asp on poplar growth and development. Our results showed that supplement of Asp at an appropriate concentration, that is, 0.5 mM in the present study, had the best growth-promoting effect on poplars. It significantly increased poplar biomass and height, and simultaneously elevated the photosynthetic parameters, the chlorophyll content and total free amino acid content, as well as the activity of N metabolism-related enzymes in poplars-treated with Asp in comparision with the control plants without Asp addition. Furthermore, the expression of Asp-metabolism pathway genes (AspAT1, AspAT6, AspAT10, AK1, ASS1 and ASS2), key chlorophyll synthesis gene (LHCB3) and cell division gene (CYCD3) was all dramatically upregulated in response to Asp application, suggesting that Asp-induced effect invoked photosynthesis activation and metabolism reprogramming. More interestingly, our results showed that the levels of various phytohormones, such as auxin and cytokinins were remarkably altered, and key auxin transport gene (PIN1c-2), auxin conjugation gene (GH3.6–2) were induced by Asp treatment, indicative of the possible involvement of plant hormones under the effect of Asp, especially fine-tuning auxin homeostasis by forming IAA-Asp conjugates to store auxin and catabolizing IAA-Asp to release auxin, may account for Asp-mediated growth modulation to an extent in poplars. Our study provides a novo insight into the growth promotion effect of Asp on poplars, especially, when the N source is limited, even though the underlying mechanism of Asp-induced stimulation action needs further in-depth investigation.