Aspartic Acid Content Research Articles

Growth performance, carcass composition, physico-chemical traits and amino acid profile of meat depending on wormwood (Artemisia absinthium L.) dietary supplementation in broilers

Abstract. The present study was conducted to determine the effect of dietary inclusion of the wormwood (Artemisia absinthium L.) meal on growth performance, carcass composition, physico-chemical traits and amino acid profile in meats of fattened broilers. In a completely randomised block design, a total of 288 female broilers that were 21 d old (Ross 308) were divided into four dietary groups and fed for 3 weeks: the control basal broiler diet (C), without any anticoccidial or wormwood herb (WH) supplementation, and the C diet plus 10 g (WW1 group), 50 g (WW5 group) or 100 g (WW10 group) of WH meal supplementation per kilogram of basal diet. At the end of the experiment (day 42), broilers were randomly selected for carcass composition and meat quality trait evaluation. In conclusion, the final live weight of chickens was not affected by diets with higher WH levels (P>0.05). For the entire experimental period, the feed conversion ratio raised with an increasing WH level in diets, showing the highest value in chickens of the WW10 group (P<0.01). Dietary supplementation with wormwood (WW) had no negative effects on the carcass composition or on the chemical and physical traits of meat quality assessed. By contrast, it can be assumed that WH dietary supplementation influenced, predominantly, proteosynthesis of chickens, resulting in alteration of amino acid profiles in meats, where especially increasing aspartic acid and valine contents (P<0.001) in the leg meat were found. Our findings indicate that the supplementation of 5 % WH to the diet showed favourable results for chicken performance. However, it is necessary to conduct further studies dealing with WH dietary effects on metabolism and heath control in chickens.

Integrated metabolomic and transcriptomic analyses reveal themolecular mechanism of amino acid transport between source and sink during tea shoot development.

The weighted gene co-expression network analysis and antisense oligonucleotide-mediated transient gene silencing revealed that CsAAP6 plays an important role in amino acid transport during tea shoot development. Nitrogen transport from source to sink is crucial for tea shoot growth and quality formation. Amino acid represents the major transport form of reduced nitrogen in the phloem between source and sink, but the molecular mechanism of amino acid transport from source leaves to new shoots is not yet clear. Therefore, the composition of metabolites in phloem exudates collected by the EDTA-facilitated method was analyzed through widely targeted metabolomics. A total of 326 metabolites were identified in the phloem exudates with the richest variety of amino acids and their derivatives (93), accounting for approximately 39.13% of the total metabolites. Moreover, through targeted metabolomics, it was found that the content of glutamine, glutamic acid, and theanine was the most abundant, and gradually increased with the development of new shoots. Meanwhile, transcriptome analysis suggested that the expression of amino acid transport genes changed significantly. The WGCNA analysis identified that the expression levels of CsAVT1, CsLHTL8, and CsAAP6 genes located in the MEterquoise module were positively correlated with the content of amino acids such as glutamine, glutamic acid, and theanine in phloem exudates. Reducing the CsAAP6 in mature leaves resulted in a significant decrease in the content of glutamic acid, aspartic acid, alanine, leucine, asparagine, glutamine, and arginine in the phloem exudates, indicating that CsAAP6 played an important role in the source to sink transport of amino acids in the phloem. The research results will provide the theoretical basis and genetic resources for the improvement of nitrogen use efficiency and tea quality.

Assessment of hydrolysis of partially defatted black soldier fly larvae meal in diets for Nile tilapia Oreochromis niloticus

The chitin content of black soldier fly (Hermetia illucens) larvae meal (BSFM) is known to negatively affect its digestibility by fish. Nile tilapia (Oreochromis niloticus) tolerates well BSFM in the diet. However, chemical hydrolysis of dietary BSFM has not previously been attempted for this species. In this study, based upon a low-fishmeal control diet (40% crude protein and 9% crude fat), three levels of dietary protein, 25%, 50%, and 75%, were replaced by partially defatted BSFM, subjected or not to a prior hydrolysis treatment with formic acid and fed to Nile tilapia juveniles (initial body weight: 0.26 ± 0.00 g). The hydrolysis treatment did not modify greatly the proximate and amino acid composition of the diets, nor did it improve their in vivo apparent digestibility coefficients of dry matter or crude protein. However, it significantly increased the contents of arginine, taurine, and tyrosine, and significantly reduced the contents of methionine, valine, aspartic acid, and glutamic acid in muscle tissue of Nile tilapia. The hydrolysis treatment also decreased fish growth significantly. In contrast, for diets not containing hydrolyzed BSFM, not only did fish fed all three levels of protein replacement grow satisfactorily, but the diets with the levels of replacement of 50% and 75%, with final weights of 23.04 and 23.11 g, respectively, elicited superior fish performance, as compared to the diet with 25% replacement (final weight of 20.09 g). In addition, all three protein replacement diets produced significantly greater growth than the control diet (final weight of 17.72 g). The actual levels of inclusion of BSFM were, respectively, 14.11%, 28.21% and 42.33% of diet, the latter being the highest inclusion level of BSFM reported to date for successful growth of Nile Tilapia.

Nutritional characteristics and antiradical activity of turmeric (Curcuma longa L.), beetroot (Beta vulgaris L.), and carrot (Daucus carota L.) grown in Bangladesh

Curcuma longa L. (turmeric), Beta vulgaris L. (beetroot), and Daucus carota L. (carrot) grown in Bangladesh were analyzed for nutritional and phytochemical contents to reveal their comparative nutritional compositions and antiradical properties. Ash, protein, and carbohydrate content were significantly preeminent in beetroot as compared to others. Whereas fat content was found to be high in turmeric, carrots contained a great percentage of crude fiber. Beetroot was shown to have much greater potassium, calcium, and iron levels than others. Regarding amino acids, glutamic acid was found to be greater in beetroot and carrot whereas turmeric had significantly high aspartic acid content. Leucine had the highest concentration among essential amino acids in these three samples. Total antioxidant activity, total flavonoids, and phenolic contents in the methanolic extract of turmeric were found to be substantially higher than in beetroot and carrot. Furthermore, the extract of turmeric (IC50 value: 13.46 μg/mL) scavenged 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) free radicals considerably to a greater extent than beetroot (IC50 value: 380.61 μg/mL) and carrot (IC50 value: 1252.85 μg/mL). A positive correlation was found between the phytochemical contents and antiradical activity. The information from this study will help to find the potential ingredients from these plants for functional food.

Influence of phosphorous treatment and aspartic acid spray on a few aspects of oat Avena sativa L. growth and production.

The experiment was carried out in the Abu Al-Fadl Forest Nursery, the Plant Production Department, Al-Diwaniyah Agriculture Directorate (3 km north-east of Al-Diwaniyah city) during the winter season 2021-2022 to determine the effect of four levels of phosphate fertilizer (0, 30, 60 and 90 kg P ha-1 ) and two concentrations of aspartic acid spray (0 and 200 mg aspartic L -1 ), on the growth and yield of oats Avena sativa L. Shifa cultivar. The experiment was applied according to a Randomized Complete Block Design (RCBD) by a split plot with three replicates. The levels of phosphate fertilizer were distributed in the main plots, while the concentrations of amino acids occupied the sub-plots. The results showed the following: the superiority of plants fertilized at the fertilizer level of 90 kg P ha-1 significantly on the number of tillers, the number of dahlias, the weight of a thousand grains g, the biological yield and grain yield were given 532 tillers m-2 , 468.58 dalia m-2 , 46.76 g, 56.39 mcg ha-1 , and 8.92 mcg ha-1 , respectively, the results also showed that the plants treated with aspartic acid (concentration 200 mg L -1 ) were significantly superior to the number of tillers and the number of dahlias, it gave 527.75 tillers m-2 and 483.58 Dalia m-2 . The interaction between the two experimental factors (fertilization at a level of 90 kg P ha-1 and spraying with aspartic acid at a concentration of 200 mg L-1 ) significantly affected the biological yield and grain yield. Keywords: phosphate fertilization, aspartic acid, growth, yield, oats Avena sativa L.

Serum metabolomic profiling unveils distinct sex-related metabolic patterns in NAFLD.

Obesity poses an increased risk for the onset of Nonalcoholic fatty liver disease (NAFLD). The influence of other factors, such as sex in the incidence and severity of this liver disease has not yet been fully elucidated. Thus, we aimed to identify the NAFLD serum metabolic signatures associated with sex in normal, overweight and obese patients and to associate the metabolite fluctuations across the increasing liver steatosis stages. Using nuclear magnetic resonance (NMR) serum samples of 210 NAFLD cases and control individuals diagnosed with liver U/S, our untargeted metabolomics enquiry provided a sex distinct metabolic bouquet. Increased levels of alanine, histidine and tyrosine are associated with severity of NAFLD in both men and women. Moreover, higher serum concentrations of valine, aspartic acid and mannose were positively associated with the progression of NAFLD among the male subjects, while a negative association was observed with the levels of creatine, phosphorylcholine and acetic acid. On the other hand, glucose was positively associated with the progression of NAFLD among the female subjects, while levels of threonine were negatively related. Fluctuations in ketone bodies acetoacetate and acetone were also observed among the female subjects probing a significant reduction in the circulatory levels of the former in NAFLD cases. A complex glycine response to hepatic steatosis of the female subjects deserves further investigation. Results of this study aspire to address the paucity of data on sex differences regarding NAFLD pathogenesis. Targeted circulatory metabolome measurements could be used as diagnostic markers for the distinct stages of NAFLD in each sex and eventually aid in the development of novel sex-related therapeutic options.

Controlling water deficiency as an abiotic stress factor to improve tomato nutritional and flavour quality.

Water deficit (WD) irrigation techniques to improve water use efficiency have been rapidly developed. However, the effect of WD irrigation on tomato quality has not been sufficiently studied. Here, we investigated the effects of varying water irrigation levels [T1-T4: 80%, 65%, 55%, and 45% of maximum field moisture capacity (FMC)] and full irrigation (CK: 90% of maximum FMC) on tomato fruits from the mature-green to red-ripening stages, to compare the nutritional and flavour qualities of the resulting tomatoes. The proline, aspartic, malic, citric, and ascorbic acid contents increased, phenylalanine and glutamic acid contents decreased, and the total amino and organic acid contents increased by 18.91% and 26.12%, respectively, in T2-treated fruits. Furthermore, the T2-treated fruits exhibited higher K and P contents alongside improved characteristic aromas. These findings provide novel insights for further improvements in tomato quality while also developing water-saving irrigation techniques.

Biochemical compositions and transcriptome analysis reveal dynamic changes of embryonic development and nutrition metabolism in Chinese sturgeon (Acipenser sinensis)

The aim of this study was to investigate the energy sources and utilization patterns during embryonic development of Chinese sturgeon through analyzing the biochemical components of embryos at different development stages, and to explore the physiological characteristics and related molecular mechanism during embryogenesis in combination with an embryonic transcriptome analysis. Chinese sturgeon embryo samples were collected at different development stages (fertilized eggs, neurula stage, and tail touching head stage). The results showed that embryonic development was a process of continuous energy consumption. The change of total protein content was consistent with total amino acid content, showing a trend of increasing first and then decreasing. However, the total lipid content decreased significantly during early embryonic development. As for amino acid profile, leucine, arginine and lysine contents showed the highest level within essential amino acids (EAA), while glutamic acid, alanine, aspartic acid and serine contents showed the highest level within non-essential amino acids (NEAA). In terms of fatty acid content, the main quantitative fatty acids were C16:0 in saturated fatty acids (SFA), C18:1 in monounsaturated fatty acids (MUFA), and C22:6n-3 (DHA), C18:2n-6 as well as C20:5n-3 (EPA) in polyunsaturated fatty acids (PUFA). The content of C20:4n-6 (ARA), EPA and DHA were increased at neurula stage compared to fertilized eggs, which indicated their important roles in the structural composition during embryogenesis. Notably, Chinese sturgeon may have the ability to elongate n-3 PUFA to partially meet its requirements for highly unsaturated fatty acids (HUFA) during embryonic development. Transcriptome analysis showed that 19,078 and 6326 differential expressed genes (DEGs) were up-regulated and down-regulated respectively from fertilized eggs to neurula stage; while 3556 and 3150 DEGs were up-regulated and down-regulated respectively from neurula stage to tail touching head stage. KEGG enrichment analysis showed that the protein processing pathway was significantly enriched in early embryonic development through the up-regulated genes of imp4, pwp2, utp21, nop10, rpl10_17_35 and rps25; while the down-regulated genes of ccne1, ccna2, ccnb1, cdk1_2 and plk1 were associated with cell proliferation and differentiation pathway. In late embryonic development, the pathways related to aerobic metabolism, amino acid metabolism and lipid metabolism were significantly enriched through the up-regulated genes of mdh1, fumc, idh2, elovl6 and dgat2; and the neuroactive ligand-receptor interaction pathway was significantly down-regulated. In general, this study revealed the continuous energy consumption during embryonic development of Chinese sturgeon with specific energy substrates at different stages, and highlighted the DEGs and related pathway involved in the ontogeny and nutrient metabolism, which emphasizes the essentiality of high quality egg production for the success of captive breeding of Chinese sturgeon and would guide the broodstock nutrition for high quality egg production.

Fermented milk by Lactobacillus delbrueckii, Lacticaseibacillus paracasei, and Kluyveromyces marxianus shows special physicochemical and aroma formation during the storage

In this study, the microbial interactions among co-culture of Lactobacillus delbrueckii DPUL-F36, Lacticaseibacillus paracasei DPUL-F115, and Kluyveromyces marxianus 39 in fermented milk were evaluated during 13 days of refrigerated storage (4 ± 0.5 °C), in terms of titratable acidity, viable cell counts and metabolites. The fermented milk involving K.marxianus 39 showed a maximum lactobacilli count (4.8 × 109 CFU/mL) and titratable acidity (151.0 ± 1.7 °T). K. marxianus 39 could enrich the flavor of the fermented milk and improve the sensory quality of the fermented milk on the 5th and 9th day of storage. The contents of aspartic acid, glycine, alanine, valine, methionine, leucine, lysine, and tyrosine increased significantly, while the contents of valine, methionine, leucine, phenylalanine, and lysine in milk fermented by Lactobacillus delbrueckii DPUL-F36, Lacticaseibacillus paracasei DPUL-F115, and Kluyveromyces marxianus 39 were significantly lower than those in milk fermented by Lactobacillus delbrueckii DPUL-F36, Lacticaseibacillus paracasei DPUL-F115 during storage. The higher concentrations of acetic acid, nonanoic acid, acetoin, 2-nonanone, and 2-undecanol were observed in the fermented milk involved with K. marxianus 39. Our results showed K. marxianus 39 has the potential to be a starter culture for fermented dairy products.

Effect of "Tiaoshen Tongluo" acupuncture on nerve function injury, muscle tension and neurotransmitters through Nrf2/ROS pathway in spastic rats after stroke

To observe the effect of "Tiaoshen Tongluo" acupuncture (TTA) at "Dingzhongxian" (MS5) and right "Dingpangxian" (MS8) on neurological injury, muscle tension and neurotransmitters through nuclear transcription factor E2 related factor 2 (Nrf2)/reactive oxygen species (ROS) signaling pathway in spastic rats after stroke, so as to explore its mechanisms underlying relief of post-stroke spasm (PSS). A total of 90 male SD rats were randomly divided into 6 groups, i.e. sham operation, PSS model, medication, non-acupoint acupuncture, TTA, TTA+ML385 groups, with 15 rats in each group. The PSS model was established by middle cerebral artery occlusion. After modeling, rats of the medication group were treated by gavage of baclofen (0.4 mg/kg), once daily for 7 days. For rats of the non-acupoint acupuncture group, the spot about 10 mm above the iliac crest and below the armpit of the affected side was needled, and for those of the TTA group and TTA+ML385 group, EA stimulation (1 mA, 2 Hz/15 Hz) was applied to MS5 and right MS8 for 10 min, once daily for 7 consecutive days. Intraperitoneal injection of ML385 ［ a specific nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor, 30 mg/kg］ was given to rats of the TTA+ML385 group before TTA was performed. The rats' neurological deficit score (0-4 points) was evaluated by referring to Zea Longa's methods and the muscular spasm degree of the quadriceps femoris of the left hindlimb (0-4 points) assessed by using Ashworth scale (MAS). The muscular tension of the left quadriceps femoris was measured by using a tension sensor, and Hoffman (H)-reflex response and M and H waves of electromyogram of the muscle between the metatarsals of the left foot were measured using an electrophysiological recorder. The cerebral infarction volume was measured after 2,3,5-triphenyltetrazolium chloride (TTC) staining. The contents of γ-aminobutyric acid (GABA), glycine (Gly), glutamic acid (Glu) and aspartic acid (Asp) of the right cortical infarct area were detected by using high performance capillary electrophoresis, and the contents of 5-hydroxytryptamine (5-HT), dopamine (DA) and norepinephrine (NE) were detected by fluorescence spectrophoto-metry, as well as the level of ROS in the right cerebral cortical infarction tissues was detected by dihydroethidium staining. The expression levels of Nrf2 and heme oxygenase-1 (HO-1) proteins in the infarcted cerebral area were detected using Western blot. Compared with the sham operation group, the neurological deficit score, MAS score, percentage of cerebral infarction volume, Hmax/Mmax ratio, contents of Glu and Asp and ROS level were significantly increased (P<0.001), whereas the muscle tone, stimulation threshold for inducing H-reflex, GABA, Gly, 5-HT, DA and NE contents, cerebral Nrf2 and HO-1 protein expression levels were apparently decreased (P<0.001) in the model group. In comparison with the model group, the neurological deficit score, MAS score, percentage of cerebral infarction volume, Hmax/Mmax ratio, contents of Glu, Asp and ROS levels were decreased (P<0.001), and the muscle tone, stimulation threshold for inducing H-reflex, GABA, Gly, 5-HT, DA and NE contents, Nrf2 and HO-1 protein expressions were increased (P<0.001, P<0.01) in both the medication and TTA groups. No significant differences were found between the non-acupoint group and model group, and between the medication and TTA groups in all the indexes mentioned above (P>0.05). After administration of ML385, the effects of TTA in reducing neurological deficit score, MAS score, Hmax/Mmax, percentage of cerebral infarct volume, Glu, Asp, ROS, and up-regulating H-reflex threshold, GABA, Gly, 5-HT, DA, NE, Nrf2 and HO-1 levels were eliminated (P<0.001，P<0.05,P<0.01). TTA can improve neurological behavior and muscle spasm in rats with PSS, which may be associated with its functions in regulating the levels of neurotransmitters in the cortical infarcted area by activating the Nrf2/ROS signaling pathway.

Effects of supplemental root-zone pipe heating systems on the growth and development of strawberry plants in a greenhouse during the winter season

ABSTRACT The effects of two types of supplemental root-zone pipe heating systems for strawberry (Fragaria × ananassa) cultivation in a conventionally heated greenhouse during the winter were compared. ‘Seolhyang’ strawberry transplants transplanted on coir grow bags were treated for crown-based heating (CBH) and root-based heating (RBH). The medium temperatures in the RBH system resulted in the longest daily retention time for the optimum root-zone temperature in February, March, and April. The RBH system resulted in the thickest crown diameter, heaviest fresh leaf and root weights, and greatest dry weight distribution in roots. The fruit yield had no significant difference according to the heating systems, except for slightly delayed flower development in the second flower clusters in the RBH system. Aspartic and glutamic acid contents in leaves decreased in the CBH and RBH systems, compared to control. The results indicate that the RBH system may promote the vegetative shoot and root growth of strawberry plants with stable root-zone temperatures, without negatively affecting fruit yield, which can support continuous fruit production in the long-term off-season winter cultivation.

Content of Amino Acids in Plants at Different Levels of Lead in the Soil

The effect of lead on the amino acid composition of annual fodder grasses was studied. It was found that in response to soil pollution in plants, the content of nitrogen and amino acids in the composition of proteins increased. Significant changes in the content of nitrogen and most amino acids in the legume plant occurred at a content of mobile lead from 2.2 to 10.0 mg/kg. The contamination caused an increase in the relative content of proline and aspartic acid and a decrease in the proportion of glutamic acid in pea proteins. In the biomass of oats, the relative content of aspartic and glutamic acids has increased, the proportion of proline has decreased. Starting from the concentration of lead in the soil of 5.5 mg/kg, the proportion of essential amino acids in the proteins of the legume plant decreased.

Chemical and physical characterization of microencapsulated Spirulina fermented with Lactobacillus plantarum

Spirulina fermented by lactic acid bacteria (LAB) stands out among innovative fermented products with bioactive properties. In addition, the fermentation of algae with LAB has a significant effect on protein, essential amino acid content, essential fatty acid, etc. Changes in nutritional components, colour and morphological appearances of unfermented and fermented Spirulina as a result of microencapsulation with different ratios of coating material were investigated. The fermentation of wet Spirulina was carried out with Lactobacillus plantarum FI 8595 at 37 °C for 72 h under anaerobic condition. Microencapsulation of unfermented (USp) and fermented Spirulina (FSp) was performed by spray drying using 170 °C air inlet temperature, 20 mL/min feed flow rate and different ratios of maltodextrin. After fermentation, there was an increase in dry matter and crude ash contents unlike the protein content. Aspartic acid, histidine and lysine concentrations were found to be significantly higher in FSp compared to USp. The main fatty acids in USp and FSp were palmitic (27.39–31.11 %), gamma linolenic (17.41–18.93 %), linoleic (8.11–10.45 %) and palmitoleic acids (4.36–5.05 %). A significant decrease was observed in the phycocyanin content of Spirulina after fermentation. However, the highest total organic acid content was observed in spray dried fermented Spirulina groups (9–22 g/100 g). Increasing maltodextrin (MD) concentrations caused a significant reduction in moisture content of USp and FSp and provided more effective drying. In addition, with the increase of MD addition, the essential/nonessential amino acid ratio raised from 0.83 to 1.26 and from 0.72 to 0.76 in USp and FSp, respectively. According to the SEM results, it was observed that the fermented Spirulina were coated more effectively with the coating material. In addition, fermentation and microencapsulation revealed positive effects on colour properties of Spirulina. Therefore, it can be concluded that microencapsulation of fermented Spirulina has significant potential for the production of new functional foods.

FaGAPC2/FaPKc2.2 and FaPEPCK reveal differential citric acid metabolism regulation in late development of strawberry fruit.

Citric acid is the primary organic acid that affects the taste of strawberry fruit. Glycolysis supplies key substrates for the tricarboxylic acid cycle (TCA cycle). However, little is known about the regulatory mechanisms of glycolytic genes on citric acid metabolism in strawberry fruits. In this study, the citric acid content of strawberry fruit displayed a trend of rising and decreasing from the initial red stage to the full red stage and then dark red stage. Thus, a difference in citric acid metabolic regulation was suspected during strawberry fruit development. In addition, overexpression of either cytoplasm glyceraldehyde-3-phosphate dehydrogenase (FxaC_14g13400, namely FaGAPC2) or pyruvate kinase (FxaC_15g00080, namely FaPKc2.2) inhibited strawberry fruit ripening and the accumulation of citric acid, leading to a range of maturity stages from partial red to full red stage. The combined transcriptome and metabolome analysis revealed that overexpression of FaGAPC2 and FaPKc2.2 significantly suppressed the expression of phosphoenolpyruvate carboxykinase (FxaC_1g21491, namely FaPEPCK) but enhanced the content of glutamine and aspartic acid. Meanwhile, the activities of PEPCK and glutamate decarboxylase (GAD) were inhibited, but the activities of glutamine synthase (GS) were increased in FaGAPC2/FaPKc2.2-overexpressed fruit. Further, functional verification demonstrated that overexpression of FaPEPCK can promote strawberry fruit ripening, resulting in a range of maturity stage from full red to dark red stage, while the citric acid synthase (CS) activities and citric acid content were significantly decreased. Overall, this study revealed that FaGAPC2/FaPKc2.2 and FaPEPCK perform an important role in reducing citric acid content in strawberry fruit, and FaGAPC2/FaPKc2.2 mainly by promoting the GS degradation pathway and FaPEPCK mainly by inhibiting the CS synthesis pathway.

Solid-State Fermentation of Soybean Meal with Edible Mushroom Mycelium to Improve Its Nutritional, Antioxidant Capacities and Physicochemical Properties

Soybean meal is a class of by-products obtained from the processing of soybean products. Despite its high nutritional value, the presence of glycoside isoflavones limits human use of soybean meal. This study evaluated the effect of solid-state fermentation (SSF) with different edible mushroom mycelia (Pleurotus ostreatus, Hericium erinaceus, and Flammulina velutipes) on the proximate composition, antioxidant properties, and physicochemical properties of fermented soybean meal powder (SP). The results revealed that fermented SP had a higher nutritional value when compared to SP. P. ostreatus was the most pronounced among the three species. Crude protein content was found to have increased by 9.49%, while the concentration of glutamate and aspartic acid increased by 23.39% and 23.16%, respectively. SSF process significantly increased the total polyphenol content (TPC) and aglycone isoflavone content by 235.9% and 324.12%, respectively, resulting in increased antioxidant activity (evaluated by the DPPH, •OH, ABTS+ assays). Microstructural changes in fermented SP and nutrient degradation and utilization were observed. Thus, fermented SP can be used as a raw material with enhanced nutritional properties to develop new functional foods, such as plant-based foods represented by plant meat. It provides a promising approach for increasing the added value of soybean meal.

Isolation and functional verification of an aspartate aminotransferase gene from Neoporphyra haitanensis

BackgroundNeoporphyra haitanensis is a commercial laver species in China. Aspartic acid is an important flavor amino acid, and aspartate aminotransferase (AAT) is a crucial enzyme in its biosynthesis. In this study, we cloned one AAT gene (NhAAT) from the red alga N. haitanensis and investigated its sequence structure, transcriptional expression and enzymatic characteristics. The purpose of our research is to obtain a functional AAT responsible for the biosynthesis of aspartic acid from red seaweeds, which has the potential to influence the flavor of N. haitanensis.ResultsSequence analysis showed that NhAAT contains a conserved domain of Aminotran_1_2, which belongs to the transaminase superfamily. The secondary structure of NhAAT is dominated by α-helix. The results of enzymatic characterization illustrated that the NhAAT has highest catalytic activity at 45 °C and pH 7.5 in both forward and reverse reactions. The calculated Km values of NhAAT was 5.67 and 6.16 mM for L-glutamic acid and L-aspartic acid, respectively. Quantitative analysis showed that the NhAAT expression of N. haitanensis collected in late harvest (Dec) was 4.5 times that of N. haitanensis collected in early harvest (Oct), while the aspartic acid content of N. haitanensis collected in late harvest (Dec) was 1.2 times that of N. haitanensis collected in early harvest (Oct).ConclusionThe results of enzyme kinetics indicated that NhAAT prefers to catalyze the reaction in the direction of aspartic acid production. Moreover, the trend of NhAAT expression level was consistent with that of aspartic acid content in N. haitanensis in different harvest periods. Our research is helpful to understand the accumulation and regulation of amino acids in N. haitanensis in different habitats and the taste difference of N. haitanensis in different harvest periods.

Improving acid resistance of Escherichia coli base on the CfaS-mediated membrane engineering strategy derived from extreme acidophile.

Industrial microorganisms used for the production of organic acids often face challenges such as inhibited cell growth and reduced production efficiency due to the accumulation of acidic metabolites. One promising way for improving the acid resistance of microbial cells is to reconstruct their membranes. Herein, the overexpression of cfa2 from extreme acidophile endowed E. coli with high-performance on resistance to the acid stress. The engineered strain M1-93-Accfa2, constructed by CRISPR/Cas9-mediated chromosome integration, also exhibited a significantly higher resistance to severe acid stress. The analysis of fatty acid profiles indicated that the proportion of Cy-19:0 in the cell membrane of M1-93-Accfa2 increased by 5.26 times compared with the control, while the proportion of C18:1w9c decreased by 5.81 times. Correspondingly, the permeability and fluidity of the membrane decreased significantly. HPLC analysis demonstrated that the contents of intracellular glutamic acid, arginine, methionine and aspartic acid of M1-93-Accfa2 were 2.59, 2.04, 22.07 and 2.65 times that of the control after environmental acidification, respectively. Meanwhile, transmission electron microscopy observation indicated that M1-93-Accfa2 could maintain a plumper cell morphology after acid stimulation. M1-93-Accfa2 also exhibited higher-performance on the resistance to organic acids, especially succinic acid stress. These results together demonstrated the great potential of M1-93-Accfa2 constructed here in the production of organic acids.

THE AMINO ACIDS CONTENT IN GRAPE BY-PRODUCTS FROM SLOVAKIA AND AUSTRIA

The aim of the experiment was to determine the amino acid content in 3 grape varieties by-products (bunch, pomace, stem) from Austria (AT) and Slovakia (SK). In total, 54 samples from 3 varieties Zweigelt (ZG), Pinot Blanc (PB) and Green Veltliner (GV) white skinned from 6 different locations (Nitra and Vienna wine region) of Vitis vinifera sp. were analysed. In each variety the amino acids composition was determined for the whole grape (bunch) and by-products of wine industry (pomace, stems). Samples of grape by-products were freeze dried, homogenized and analysed for amino acids concentration using amino acid analyzer AAA 400 (Ingos, Prague). Descriptive statistics (means, standard error of mean, minimum maximum), differences between varieties (Tukey test, p &lt; 0.05) using One-way ANOVA and differences between the countries with independent samples T-test (p &lt; 0.05) by IBM SPSS v. 20.0 were generated. After the amino acid analysis in grape bunch, pomace and stem in general the highest content of glutamic and aspartic acid was found. However, the grape pomace amino acid content is highly variable and statistically different between the varieties and countries. In contrary, lower variability in amino acids content between the varieties was found in grape stem. However, similar pattern in amino acids with the lowest content between the countries and varieties in grape by-products was observed. Finally, low content of Cysteine, Methionine, Histidine and Proline was found.

Evolutionary analysis of KED-rich proteins in plants.

During the course of evolution, organisms have developed genetic mechanisms in response to various environmental stresses including wounding from mechanical damage or herbivory-caused injury. A previous study of wounding response in the plant tobacco identified a unique wound-induced gene, aptly named KED due to its coding for a protein that has an unusually high content of amino acids lysine (K), glutamic acid (E) and aspartic acid (D). However, by far little is known about this intriguing gene. In this study, we investigated the evolutionary aspects of the KED-rich coding genes. We found that a consistent pattern of wound-induced KED gene expression is maintained across representative species of angiosperm and gymnosperm. KED genes can be identified in species from all groups of land plants (Embryophyta). All the KED proteins from vascular plants (Tracheophyta) including angiosperm, gymnosperm, fern and lycophyte share a conserved 19-amino acid domain near the C-terminus, whereas bryophytes (moss, liverwort and hornwort) possess KED-rich, multi-direct-repeat sequences that are distinct from the vascular plant KEDs. We detected KED-rich sequences in Charophyta species but not in Chlorophyta wherever genome sequences are available. Our studies suggest diverse and complex evolution pathways for land plant KED genes. Vascular plant KEDs exhibit high evolutionary conservation, implicating their shared function in response to wounding stress. The extraordinary enrichment of amino acids K, E and D in these groups of distinct and widely distributed proteins may reflect the structural and functional requirement for these three residues during some 600 million years of land plant evolution.

The effect of additional shading utilizing agriphotovoltaic structures on the visual qualities and metabolites of broccoli.

Agriphotovoltaic (APV) systems allow the simultaneous production of crops and electricity in the same land area. Since the reduction of yield caused by APV systems is important for food security, studies to improve the yield have been conducted steadily. However, there have been limited data on the appearance, quality, and metabolomic changes of crops. Therefore, in this study, we evaluated the visual qualities and metabolites as well as the yield of broccoli grown using an APV system during the fall season. In addition, additional shading treatment was performed, and the same qualities were evaluated. In the spring season, an additional cultivar that does not express anthocyanins was cultivated. Glucosinolate content was more sensitive to the seasonal environment and the type of cultivar than it was to treatment type. The additional shading treatment had a positive effect on the visual qualities of anthocyanin-expressing broccoli cultivar regardless of the season, and we observed that even a cultivar that does not express anthocyanins can be greener. Regardless of cultivar, higher chlorophyll content was detected in broccoli florets with additional shading treatment under the APV system. In addition, reduced anthocyanin content was observed (6.1 mg g-1 DW; about 20% of that obtained on open-field). Aspartic acid content was enhanced upon additional shading treatment. Pathway analysis revealed changes in anthocyanin, alanine, aspartic acid, and glutamic acid metabolism. Overall, our findings suggests that it is possible to produce crops with better visual qualities by utilizing APV systems.