Total Amylase Activity Research Articles

Interactive Effects of Dietary Probiotic and Succinic Acid on the Growth Performance, Digestive Enzyme Activities, Immunomodulation, Antioxidative Capacity, and Disease Resistance in Rainbow Trout (Oncorhynchus mykiss) Juveniles

Abstract The current study was carried out to explore the effects of lactofeed (LA) as a multi-strain probiotic and succinic acid (SA) on growth variables, gut lactic acid bacteria count, digestive enzymes, innate immune responses, antioxidant capacity, and resistance against yersinia ruckeri in rainbow trout juveniles (Oncorhynchus mykiss). Three hundred sixty healthy rainbow trout juveniles (13.21±0.41 g) were randomly divided into twelve tanks (300 L) as four experimental groups. They were fed with basal diet (Control; BD), FT1: BD + 1 g/kg LA, FT2: BD + 5 g/kg SA, and FT3: BD + 1 g/kg LA + 5 g/kg SA for eight weeks. According to the results, final weight (FW), weight gain (WG), protein efficiency rate (PER), and feed conversion rate (FCR) revealed a remarkable discrepancy compared to the control group. In addition, dietary inclusion of LA (FT1 and FT3) significantly increased the specific growth rate (SGR). Dietary supplementation of LA+SA (FT3) remarkably improved total bacteria count (TBC) and amylase activity compared to the unsupplemented group. Gut lactic acid bacteria (LAB) count and digestive protease activity in all supplemented fish were remarkably higher than in unsupplemented group. Blood immunological factors including white blood cell (WBC) count, total immunoglobulin content (Ig), and the activity of lysozyme (LYZ), alternative complement pathway (ACH50), and acid phosphatase (ACP) were significantly enhanced in the supplemented groups. Neutrophil (NEU) count, skin mucus Ig and hepatic glutathione peroxidase (GPX) increased in SA (FT2 and FT3) treatments. In addition, monocyte (MON) count and skin mucus LYZ activity were significantly elevated following feeding with the FT3 diet. Other immunological parameters of skin mucus including protease activity, alkaline phosphatase (ALP) activity, and ACH50 activity, as well as hepatic superoxide dismutase (SOD) and catalase (CAT) activities increased in fish fed with diets containing LA and/or SA. Malondialdehyde (MDA) value was remarkably decreased in all supplemented rainbow trout compared to the fish fed with BD. Disease resistance against Y. ruckeri in fish fed with supplemented diets significantly improved with respect to the results obtained in the control specimens. Overall, dietary LA+SA supplementation was beneficial to improve growth performance, gut LAB count, digestive enzyme activities, innate immune responses, antioxidant capacity, and disease resistance in rainbow trout. According to these findings, 1 g/kg LA + 5 g/kg SA is suggested for adding to rainbow trout diet.

Overexpression of VaBAM3 from Vitis amurensis enhances seedling cold tolerance by promoting soluble sugar accumulation and reactive oxygen scavenging.

The VaBAM3 cloned from Vitis amurensis can enhance the cold tolerance of overexpressed plants, but VaBAM3 knock out by CRISPR/Cas9 system weakened grape callus cold tolerance. In grape production, extreme cold conditions can seriously threaten plant survival and fruit quality. Regulation of starch content by β-amylase (BAM, EC: 3.2.1.2) contributes to cold tolerance in plants. In this study, we cloned the VaBAM3 gene from an extremely cold-tolerant grape, Vitis amurensis, and overexpressed it in tomato and Arabidopsis plants, as well as in grape callus for functional characterization. After exposure to cold stress, leaf wilting in the VaBAM3-overexpressing tomato plants was slightly less pronounced than that in wild-type tomato plants, and these plants were characterized by a significant accumulation of autophagosomes. Additionally, the VaBAM3-overexpressing Arabidopsis plants had a higher freezing tolerance than the wild-type counterparts. Under cold stress conditions, the activities of total amylase, BAM, peroxidase, superoxide dismutase, and catalase in VaBAM3-overexpressing plants were significantly higher than those in the corresponding wild-type plants. Furthermore, sucrose, glucose, and fructose contents in these lines were similarly significantly higher, whereas starch contents were reduced in comparison to the levels in the wild-type plants. Furthermore, we detected high CBF and COR gene expression levels in cold-stressed VaBAM3-overexpressing plants. Compared with those in VaBAM3-overexpressing grape callus, the aforementioned indicators tended to change in the opposite direction in grape callus with silenced VaBAM3. Collectively, our findings indicate that heterologous overexpression of VaBAM3 enhanced cold tolerance of plants by promoting the accumulation of soluble sugars and scavenging of excessive reactive oxygen species. These findings provide a theoretical basis for the cultivation of cold-resistant grape and support creation of germplasm resources for this purpose.

Dietary multi-strains Bacillus spp. enhanced growth performance, blood metabolites, digestive tissues histology, gene expression of Oreochromis niloticus, and resistance to Aspergillus flavus infection

The present study tested the symbiotic effects of dietary multi-strain Bacillus probiotics (MSB) (Bacillus licheniformis, B. pumilus, and B. subtilis) in Nile tilapia (Oreochromis niloticus) exposed to Aspergillus flavus infection. Furthermore, this study investigated water quality, growth performance, blood metabolites, histological morphology, immune regulatory genes, and resistance to A. flavus infection. For 70 days, fish (n = 240) were divided into four groups in triplicate: T0 (control group; MSB0), T1 (1 g/kg, MSB1), T2 (2 g/kg, MSB2), and T3 (3 g/kg, MSB3). The immune response was then assessed by challenging all fish groups with the A. flavus pathogen. The results showed that the rearing water quality, fish growth, and blood parameters, as well as total proteins, albumin, globulins, and amylase activity were significantly (P < 0.05) increased in all MSB-treated groups with the best results in MSB2 and MSB3 groups. Meanwhile, the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), cholesterol, and glucose levels were significantly (P < 0.05) modulated, particularly at higher concentrations of the probiotic mixture (MSB3 group). Fish fed with various levels of MSB showed a maintained histological structure of the hepatopancreas, intestine, and spleen tissues. The mRNA expression of growth hormone (GH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor receptor-1 (IGF-1R), and interleukin-8 (IL-8) were increased in a dose-dependent manner due to MSB dietary inclusion (P < 0.05). Conversely, the mRNA expression of interleukin-1β (IL-1β) gene was significantly decreased in MSB groups compared to untreated group (P < 0.05). Surprisingly, supplemented groups in Bacillus spp. probiotics exhibited significant modulations in all computed parameters. MSB supplementation improved the pathogenic tolerance of tilapia after change with A. flavus. The integration of growth performance, biochemical, and transcriptomic results confirms that the dietary intervention of multi-strain Bacillus spp. is symbiotic and enhances the benefits for the maintenance of O. niloticus’ health, growth, and digestion. This is achieved by supporting growth genes, reducing inflammatory genes, and enhancing immune-antioxidant resistance to combat A. flavus infection.

Mitigation of cadmium toxicity stress by magnetopriming during germination of soybean

Cadmium (Cd) is a highly toxic heavy metal that poses a significant threat to food safety and agricultural production worldwide. Its solubility enables easy entry into plants, leading to reductions in seed germination, growth and crop yield. Thus, it is crucial to discover methods to alleviate the harmful impact of Cd on plant growth. Magnetopriming (MP) is a non-invasive and cost-effective technique that has been proposed to improve plant growth under abiotic stress conditions. The current study investigated the potential of MP to improve the seed germination, early seedling growth and biochemical responses of soybean under Cd toxicity. Soybean seeds were magnetoprimed with static magnetic field (SMF) strength of 200 mT for 1 hour before germination. The unprimed and magnetoprimed seeds were grown under different concentrations of cadmium chloride (0, 25, 50, 75, 100, 200 and 300 μM CdCl2) in Petri plates for five days in the dark at 25 + 1°C. The results revealed that Cd toxicity significantly reduced the germination percentage and inhibited the seedling growth parameters and increased oxidative stress, as determined by malondialdehyde (MDA) content in soybean seedlings from unprimed seeds. The inhibitory effect was increased with increasing concentration of Cd. However, MP remarkably increased the germination percentage, seedling growth parameters, activities of total amylase and protease, and hydrogen peroxide (H2O2) content and decreased MDA and proline content in germinating soybean seedlings at all concentrations of Cd. These findings suggest that MP can alleviate the adverse effects of Cd stress in soybean seedlings and increase the tolerance index towards Cd toxicity by enhancing the activity of amylotic and proteolytic enzymes and reducing oxidative stress.

Comparative Analysis of Saccharification Characteristics of Different Type Sweetpotato Cultivars.

As an important characteristic crop in China, sweetpotato plays an important role in the intake and supplement of nutrients. The saccharification characteristics of sweetpotato determine the edible quality and processing type. Exploring the saccharification characteristics of sweetpotato is of great significance to the selection of processing materials and the formation mechanism of service quality, but there are few relevant studies. A comparison study of two high saccharification varieties (Y25 and Z13) and one low saccharification variety (X27) was conducted to analyze their storage roots physical and chemical properties. The results show that the dry matter content, starch, and amylose content of Y25 and Z13 were significantly different from those of X27. Furthermore, the total amylase activity was significantly higher than that of X27. On the other hand, the starch gelatinization temperature was significantly lower than that of X27. The starch reduction in Y25 and Z13 is four times more than that in X27, and the maltose content of Y25 and Z13 is more than two times that of X27. Finally, the scores of sensory evaluation and physiological sweetness were significantly higher than those of X27. The results provide a theoretical basis for understanding the saccharification characteristics of sweetpotato varieties and are of guiding significance for the selection of sweetpotato parents.

EFFECT OF SHORT STARVATION AND REFEEDING ON GROWTH, BODY COMPOSITION, AND DIGESTIVE ENZYMES ACTIVITIES IN YELLOW RASBORA (Rasbora lateristriata Blkr.)

Digestive enzyme activities of Yellow Rasbora (Rasbora lateristriata) had been reported, but only focused on a daily feeding strategy. The effect of starvation and refeeding on the growth, body composition, and digestive enzyme activities in Yellow Rasbora has never been reported. This study aimed to know the most efficient feeding strategy for growth, body composition, and digestive enzyme activities of Yellow Rasbora. The experiment was conducted in 20 aquariums using two months old fingerling. Four different feeding strategies were tested; twice feeding a day, one-day starvation and six days refeeding, two days starvation and five days refeeding, and four days starvation and ten days refeeding. The result showed that different feeding strategies had no significant effect on all growth parameters. The result proved that Yellow Rasbora could compensate for starvation through absolute growth, with the highest value achieved in two days of starvation and five refeeding. No significant value was also observed on crude protein, and lipid contents indicate that starvation does not affect the utilization of protein and lipid reserves. This result was consistent with fish condition factors which did not differ among treatments. The feeding strategy did not significantly affect total protease, trypsin, and amylase activities, but significantly affected chymotrypsin, lipase, and alkaline phosphatase activities. All parameter indicated that two days starvation and five days refed duration showed similar values to daily feeding. Therefore, it is concluded that two days starvation and five days refeeding method is the most efficient feeding strategy for Yellow Rasbora cultivation.

Stimulating Role of Calcium and Cyclic GMP in Mediating the Effect of Magnetopriming for Alleviation of Salt Stress in Soybean Seedlings

This current study examined the role of calcium (Ca) and Cyclic GMP (cGMP) in mitigating the adverse effect of salt stress through magnetopriming of soybean cultivar JS-335 seeds with a static magnetic field (SMF, 200 mT for 1 h). The salt stress (50 mMNaCl) extensively reduced the early seedling growth (64%), vigour Index-I (71%), vigour Index-II (39%), total amylase (59%), protease (63%), and nitrate reductase (NR, 19%) activities in un-primed soybean seedlings. However, magnetopriming and Ca treatment enhanced all of these measured parameters along with remarkable increase in reactive oxygen species (ROS) and nitric oxide (NO) content. The exogenous application of Ca2+, cGMP and ROS regulators such as nifedipine (Ca2+ channel blocker), EGTA, ethylene glycol-β-amino ethyl ether tetra acetic acid (Ca2+chelators), genistein (cGMP blocker), and dimethyl thiourea (DMTU, H2O2 inhibitor) negatively affects the SMF-induced seedling length, seedling vigour, ROS, NO, and enzyme activities such as protease, total amylase, and NR in soybean seedlings. Results presented by using specific various biochemical inhibitors of Ca, cGMP, or ROS signalling in vivo indicated that Ca and cGMP are also involved with ROS and NO in the signal transduction of magnetic field enthused soybean seed germination and seedling growth under salt stress.

Osmoregulatory Appraisal of Some Osmoprotectants on Hydrolytic Activities of Some Enzymes on Seeds of Two Water Stressed Cultivars of Sorghum bicolor (Moench)

Enzymes play significant roles in metabolic processes of seeds. Therefore, this study evaluated osmoregulatory potential of some osmoprotectants on activities of some hydrolytic enzymes in the seeds of two cultivars (SOSAT.C-88 and CV. LCIC 9702) of sorghum bicolor. Matured seeds of the two cultivars were harvested and prepared for alpha, beta, total amylase and proteinase activities assay. The osmoprotectants produced significant variations on the enzymes at 10 and 14 days (DA) of 8 weeks after treatments (WAT). Seeds of well-watered SOSAT.C-88 produced higher alpha (2.10 IU/ml), beta (1.70 IU/ml) and total amylase activities (3.30 IU/ml) at 14 days (DA). Higher alpha (2.01 IU/ml and total amylase activities (2.61 IU/ml) were recorded in the seeds of CV. LCIC 9702 well-watered at 14 days DA 8WAT. Furthermore, total amylase activities (3.87 IU/ml) were recorded in the seeds produced by CV. LCIC 9702 well-watered at 14 days DA. Significant increase was noticed in beta (1.14 IU/ml) and alpha amylase (1.58 IU/ml) in the seeds of CV. LCIC 9702 treated with mycorrhiza. CV. LCIC 9702 well watered produced highest proteinase activities (1.57 U/ml) while least of the parameters were recorded in SOSAT.C-88 and CV. LCIC 9702 droughted. In conclusion, the osmoprotectants had regulatory effects on the activities of hydrolytic enzymes therefore the use of the osmoprotectants in farming should be encouraged.

Association Between Salivary Cytokines, Chemokines and Growth Factors and Salivary Gland Function in Children with Chronic Kidney Disease.

Chronic kidney disease (CKD) is a systemic inflammatory disease that leads to multiple organ complications not only in the kidneys and the cardiovascular system, but also in the oral cavity. CKD children experience reduced saliva secretion (hyposalivation), which leads to increased incidence of dental caries and significant impairment of patients' quality of life. However, the causes of salivary gland dysfunction in children with CKD are unknown. The present study is the first to evaluate the inflammatory and anti-inflammatory profile in the saliva of children with CKD at different stages of renal failure with normal and reduced salivary gland function. Thirty children with CKD (age 9-16) and thirty age- and gender-matched healthy children were classified for the study. Salivary inflammatory and anti-inflammatory profile were assayed using the multiplex ELISA assay. We demonstrated statistically significant changes in salivary pro-inflammatory (↑TNF-α, ↓IL-7), anti-inflammatory (↑IL-10), Th1 (↑INF-γ, ↑IL-15), Th2 (↑IL-4, ↑IL-5, ↑IL-6, ↑IL-9) and Th17 (IL-17) cytokines as well as chemokines (↑MCP-1/CCL-2, ↑MIP-1α/CCL3, ↓MIP-1β/CCL4, ↓EOTAXIN/CCL11) and growth factors (↑G-CSF, ↑FGF) in unstimulated saliva of children with CKD compared to the controls. Although the evaluation of the salivary inflammatory profile does not indicate a particular dominance of any of the branches of the immune system, we observed a statistically significant increase in the concentration of all Th2 cytokines assayed. The multivariate regression analysis showed that the content of salivary cytokines, chemokines and growth factors depends on the secretory function of the salivary glands, ie, salivary flow, total protein concentration and amylase activity in the saliva. Salivary MIP-1α/CCL3 was the most effective to differentiate children with CKD and hyposalivation from patients with normal saliva secretion. Inflammation is involved in salivary gland dysfunction in children with CKD, although further studies on in vitro and in vivo models are necessary to confirm this hypothesis.

Exogenous Hemin alleviates NaCl stress by promoting photosynthesis and carbon metabolism in rice seedlings

It is widely known that salt stress restricts rice growth and productivity severely. However, little information is available regarding the stage of rice seedlings subjected to the Heme oxygenase 1 (HO-1) inducer, Hemin. This study aimed to investigate the effects of salt stress on two rice varieties (Huanghuazhan and Xiangliangyou 900) and the effect of Hemin in promoting photosynthesis, carbohydrate metabolism, and key enzymes under salt-stress conditions. At the stage of three leaves and one heart, Huanghuazhan (HHZ) and Xiangliangyou 900 (XLY900) were sprayed with 5 μmol·L−1 Hemin and then subjected to 50 mM NaCl stress. The results showed that NaCl stress decreased the contents of chlorophyll a, chlorophyll b, and carotenoids. Furthermore, the net photosynthetic rate (Pn) decreased remarkably and the starch content was also lowered. However, NaCl treatment enhanced the concentration of sucrose and soluble sugar, simultaneously enhancing the sucrose metabolism. Nevertheless, the foliar spraying of exogenous Hemin mediated the increase in fructose and starch content, along with the activities of key enzymes’ soluble acid invertase (SAInv), basic/neutral invertase (A/N-Inv), and sucrose synthase (SS) in rice leaves under NaCl stress. The sucrose phosphate synthase (SPS) in leaves decreased significantly, and the fructose accumulation in leaves increased. Hemin also mediated the increase of starch content and the α-amylase, total amylase, and starch phosphorylase (SP) activities under NaCl stress. Under stress conditions, the application of the Heme oxygenase 1 (HO-1) inhibitor, ZnPP failed to alleviate the damage to rice seedlings by NaCl stress. The ZnPP treatment showed similar tendency to the NaCl treatment on pigment content, gas exchange parameters and carbon metabolism related products and enzymes. However, ZnPP decreased carotenoids, fructose, starch content and enzyme activities related to starch metabolism. The regulation effect of Hemin on HuangHuaZhan was better than XiangLiangYou 900. These results indicate that Hemin improved the effects of salt stress on the photosynthesis and physiological characteristics of rice leaves as a result of enhanced carbohydrate metabolism. Thus, Hemin could alleviate the damage caused by salt stress to a certain extent.

Dietary Lactobacillus helveticus and Gum Arabic improves growth indices, digestive enzyme activities, intestinal microbiota, innate immunological parameters, antioxidant capacity, and disease resistance in common carp

The present study aimed at determining the effects of Lactobacillus helveticus (LH), Gum Arabic (GA; natural prebiotic), and their combination as synbiotic on growth performance, digestive enzymes activity, gut microbiota, innate immunity status, antioxidant capacity, and disease resistance against Aeromonas hydrophyla in common carp, Cyprinus carpio for 8 weeks. For this, 735 common carp juveniles (Mean ± standard deviation; 22.51 ± 0.40 g) were fed with 7 different diets including basal diet (C), LH1 (1 × 107 CFU/g), LH2 (1 × 109 CFU/g), GA1 (0.5%), GA2 (1%), LH1+GA1 (1 × 107 CFU/g + 0.5%), and LH2+GA2 (1 × 109 CFU/g + 1%) for 8 weeks. Dietary supplementation with GA and/or LH significantly increased growth performance, WBC, serum total immunoglobulin, superoxide dismutase and catalase activities, skin mucus lysozyme and total immunoglobulin and intestinal lactic acid bacteria. Whereas there were significant improvements in various parameters tested in different treatments, the highest improvement in growth performance, WBC, monocyte/neutrophil percentages, serum lysozyme, alternative complement, glutathione peroxidase and malondialdehyde, skin mucosal alkaline phosphatase, protease, and immunoglobulin, intestinal total bacterial count, protease and amylase activities were observed in the synbiotic treatments, particularly LH1+GA1. After an experimental infection with Aeromonas hydrophila, all experimental treatments exhibited significantly higher survival, compared to the control treatment. The highest survival was related to the synbiotic (particularly LH1+GA1), followed by prebiotic, and probiotic treatments. Overall, synbiotic containing 1 × 107 CFU/g LH + 0.5% GA can improve growth rate and feed efficiency in common carp. Moreover, the synbiotic can improve the antioxidant/innate immune systems and dominate lactic acid bacteria in the fish intestine that may be the reasons of the highest resistance against A. hydrophila infection.

Effects of Dietary Arginine Level on Growth Performance and Immune Response in Monopterus albus

To assess the dietary arginine requirement of Monopterus albus (21 ± 0.03 g), we compared six diets containing different arginine levels (2.03%, 2.58%, 3.16%, 3.63%, 4.24%, and 4.88%). The results revealed that dietary arginine content had a significant effect on weight gain (WG), specific growth rate (SGR), IL-1β, IL-10, lysozyme, and complement C3 activity in Monopterus albus ( p &lt; 0.05 ). The WG and SGR increased with increasing dietary arginine levels, and the regression analysis found that the optimum dietary arginine level for growth of rice field eel was 4.28–4.35% of the dry diet. However, the C3 and LZM activities peaked in the 2.58% arginine diet group ( p &lt; 0.05 ). The dietary arginine level had no significant effect on the viscerosomatic index, hepatosomatic index, condition factor, survival rate, nitric oxide, total nitric oxide synthase, insulin, growth hormone, trypsin, lipase, or amylase activities ( p &gt; 0.05 ). Arginine can significantly promote Monopterus albus growth; however, the immunity of Monopterus albus decreases as the arginine level exceeds 2.58%. A comprehensive assessment of growth and immunity recommends the optimum arginine level for Monopterus albus was 3.16–3.63% of the dry diet, corresponding to 6.58–7.70% of the dietary protein.

Postharvest H2O2 treatment affects flavor quality, texture quality and ROS metabolism of ‘Hongshi’ kiwifruit fruit kept at ambient conditions

The aim of this study was to investigate the effects of 0.5 M hydrogen peroxide (H2O2) on flavor, texture quality and reactive oxygen species (ROS) metabolism in harvested ‘Hongshi’ kiwifruit. Results demonstrated that H2O2 accelerated changes in flavor detected by electronic tongue (e-tongue) and electronic nose (e-nose). In addition, H2O2 treatment promoted fruit softening, as evidenced by an earlier increment in the activities of α-amylase, total amylase, pectin lyase, and pectin methylesterase. There were higher levels of superoxide anion (O2−) and protein carbonylation in H2O2-treated fruit, even though H2O2 prompted the activities of superoxide dismutase (SOD), and peroxidase (POD) during the initial storage but decreased the activities dramatically during later storage. These results indicate that H2O2 accelerates flavor formation and softening by regulating ROS metabolism in kiwifruit.

BIOCHEMICAL PROFILE OF EMBRYONIC AND NON-EMBRYONIC CALLUS OF CLERODENDRUM PHLOMIDIS L.

Clerodendrum phlomidis L. (Arani) is a medicinal plant used in the treatment of Diabetes mellitus. Enzymatic studies helps to differentiate between embryonic and non-embryonic callus at very early stage. In vitro experiments were conducted using leaf, stem, node, internode, apical bud as an explant. Callus cultured on MS basal medium supplemented with various combinations of 2, 4-D and Kinetin (1 : 1, 2 : 2, 3 : 3, 4 : 4, 5 : 5 mg/l 2,4-D : Kinetin). Large variations were observed in the callus cultures owing to hormonal variations. Higher hormonal concentration 5 mg/l 2, 4-D + 5 mg/l kinetin resulted in somatic embryoids while lower concentrations 1:1, 2:2, 3:3 mg/l, 2,4-D : kinetin resulted in non-embryonic cells. Enzymatic activities of peroxidase, IAA- oxidase, invertase, protease,  and  amylase, polyphenol oxidase (PPO), catalase and enzyme protein were estimated from cytoplasmic as well as wall-bound fractions of 2, 4, 6and 8 week old callus using standard methods. In two week old culture peroxidase and polyphenol oxidase (both wall bound and cytoplasmic) activity increases in non-embryonic callus and decreases in embryonic callus while IAA oxidase and Protease (both wall bound and cytoplasmic) activity decreases in non-embryonic callus and increases in embryonic callus. Total amylase and α-amylase activity of wall bound enzymes increases in non-embryonic callus and decreases in embryonic callus while cytoplasmic activity decreases in non-embryonic callus and increases in embryonic callus. On the basis of the above study enzymes could serve as a biochemical marker to determine the embryonic and non-embryonic callus at very early stage.

Effects of Dietary Supplementation of Plant Extract (Impim) on Growth Performance Immune Status, and Nutrient Digestibility of Broiler Chickens

The effects of dietary supplementation of plant extract (Impim) on growth performance, immune organ indexes, serum biochemical indicators, and nutrients digestibility of broiler chickens. Nine hundred one-day-old Cobb commercial broilers were randomly allocated into 3 treatments with 3 replicates in each treatment with 100 broilers in each replicate. The 3 dietary treatments were 1) control group (CON), basal diet; 2) CON + 0.02% Impim (Impim group); 3) CON + 0.002% Colistin sulfate premix + 0.004% Aureomycin premix. The trial period were 53 days. The results showed that, compared with antibiotic group, the serum total protein, amylase activity and lipase activity of broilers fed with Impim had been significantly improved by 9.91%, 18.25% and 14.73%, respectively (P 0.05) in broilers of Impim group than antibiotic group. It could be concluded that administration of the Impim to broilers’ diet improved chickens’ growth performance, had a potent immunomodulatory effect (potentiated immune response). Eventually, Impim could be used as a partial replacement to the antibiotics.

Digestive Enzyme Activities in Barred Loach (Nemacheilus fasciatus, Val., 1846.): Effect of pH and Temperature

This study aims to determine the total protease, lipase, and amylase activities at different pHs, as well as pepsin and trypsin-like at different temperatures. A total of 240 individuals have been used in this study. Enzyme activity was measured by the spectrophotometer method. The effect of pH was evaluated on protease, lipase, and amylase activity, while the effect of temperature was evaluated on pepsin and trypsin-like activities.The results showed that the total protease activity at pH 7.0-10.0 was significantly higher than pH 1.7-5.0 (P &lt;0.05). Furthermore, the activity of lipase was significantly higher at pH 5.0-7.0 than pH 1.7, 3.4, and 10.0. Also, the activity of amylase at pH 7.0-8.0 was significantly higher (p &lt;0.05) than pH 1.7-5.0 and pH 10.0. Moreover, the pepsin-like activity in the anterior gut was significantly higher (p &lt;0.05) than the posterior gut.Conversely, trypsin-like activity in the posterior gut was significantly higher (p &lt;.05) than the anterior gut. Additionally, the pepsin-like activity was significantly higher at 45°C compared to different temperatures (p &lt;0.05), whereas trypsin-like was significantly (p &lt;0.05) higher at 60 °C than othertemperatures. Conclusively, the total protease and amylase activity was higher under neutral to slightly alkaline conditions, while lipase was higher under acidic to neutral conditions. Furthermore, the pepsin-like activity was only found in the anterior gut, whereas trypsin-like was higher in the posterior gut. The optimal temperature for pepsin-like and trypsin-like activity was 45 °C and 60 °C, respectively.

Influence of wheat and rice bran fermentation on water quality, growth performance, and health status of Common carp (Cyprinus carpio L.) juveniles in a biofloc-based system

The present study was aimed to compare the effect of wheat and rice bran fermented with probiotics (Bacillus coagulants, Bacillus subtilis) on liver and intestine histology of Common carp. Additionally, its effect on water quality, growth performance, hemato-serological indices and oxidative stress in biofloc based system for Common carp juveniles was investigated. To compare fermented (FWB + BFT: fermented wheat bran, FRB+BFT: fermented rice bran) and non-fermented (WB + BFT: wheat bran, RB + BFT: rice bran) treatments, 375 healthy juveniles (25.1 ± 1.6 g) were randomly distributed in 12 tanks (70 L). In the fermented treatments, wheat and rice bran were pre-fermented for 24 h, and then added to the culture tanks and in control. No carbon source was added while 30% of the water was changed on a daily basis. After 60 days, the results revealed that total ammonia nitrogen, pH, biofloc floc volume, and dissolved oxygen decreased in the fermented sources compared with those of the non-fermented treatments. Moreover, the results indicated that fermentation improved growth performances, and the highest significant weight gain and protein efficiency ratio, along with the lowest feed conversion ratio and feed intake belonged to FWB + BFT, which was different with non-fermented brans (P < 0.05). The fish reared in FWB + BFT had a significantly higher total protease, amylase, and lipase activity than those in the non-fermented groups (P < 0.05). A significantly higher body protein was seen in the fermented treatments (P < 0.05), while due to high lipid content in rice bran, the highest body lipid content was observed in the rice bran treatments. In comparison with non-fermented treatments, the most sero-immunological parameters improved in FWB + BFT group and significant difference was seen (P < 0.05). The experimental treatments affected the antioxidant enzymes, and the highest superoxide dismutase and glutathione peroxidase as well as the lowest malondialdehyde were observed in the fermented groups, which was different with the non-fermented treatments (P < 0.05). Histological changes were found in the juveniles intestine, and mucosal layer quantification and qualification than the fermented groups significantly improved in comparison with those in non-fermented treatments (P < 0.05). Overall, the result of this experiment revealed that fermentation of complex carbon resources improves water quality and increases growth performance and health status in the biofloc system.

Transcriptome and phytochemical analyses reveal the roles of characteristic metabolites in the taste formation of white tea during the withering process

In the postharvest processing of tea leaves, withering is the first indispensable manufacturing process which produces the mellow, umami and sweet taste of white tea. In this study, we aimed to determine the dynamic changes of the main metabolites and clarify the key differentially expressed genes (DEGs) involved in forming the characteristic taste of white tea during withering. Phytochemical analyses revealed that the contents of total catechins and starch decreased continuously, whereas the contents of theaflavin, γ-aminobutyric acid (GABA), maltose, and soluble sugars increased significantly during withering (from 0–48 h). Meanwhile, the elevation of α-amylase (AMY), β-amylase (BAM), total amylase, and glutamate decarboxylase (GAD) activities may be correlated with the accumulation of GABA and maltose. By transcriptome sequencing, we detected 9 707, 15 921, 17 353, and 17 538 DEGs at 12, 24, 36, and 48 h of the withering process, respectively, compared with 0 h sample (fresh leaves). The transcript levels of most of the DEGs involved in catechin biosynthesis were significantly inhibited, whereas those involved in catechin oxidation were significantly up-regulated, which could be correlated to a decrease in catechin content and an increase in theaflavin content. The DEGs involved in GABA biosynthesis were considerably up-regulated, and the down-regulation of SPMS could reduce the competition for converting spermidine to GABA. The up-regulation of the AMY and BAM genes could trigger starch degradation, resulting in the increase of soluble sugar content. These results provide new insights into the importance of the withering process to the characteristic taste of white tea.

Low nitrogen level improves low-light tolerance in tall fescue by regulating carbon and nitrogen metabolism

Low-light (LL) stress is a primary factor contributing to turf deterioration. Previous studies have recommended the use of reduced nitrogen (N) fertility for maintaining turf grasses and improving their LL tolerance. However, the mechanism for turf grass susceptibility to LL-induced stress is still unclear. The present study investigated the role of low N in improving tall fescue photosynthesis under LL stress by regulating carbon and N metabolism. The LL stress significantly reduced tiller numbers, biomass, chlorophyll content, net photosynthetic rate ( Pn ), the maximum quantum yield of photosystem photochemistry ( Fv/Fm ), actual photochemical efficiency of photosystem II ( Φ PSII ), and the carbon and N contents in roots and leaves. The stress also reduced the sugars contents but increased the C/N ratio in the roots and leaves. However, low N alleviated the effects of LL stress by significantly increasing the tiller numbers, root length, root-to-shoot ratio, and sugars contents in roots. Under low light and low nitrogen (40 μmol m −2 s −1 PPFD + 1.0 mM N, LN-) conditions, the tiller number, Pn , soluble sugar content and protein content in the roots increased by 24.72%, 19.43%, 71.91%, and 16.05%, respectively, compared to the low light and normal nitrogen (40 μmol m −2 s −1 PPFD + 6.0 mM N, LN) conditions. Additionally, the activities of sucrose synthase (SS), glutamate dehydrogenase (GDH), and total amylase (AMY) in leaves and the activity of glutamate synthase (GOGAT) in roots were also remarkably enhanced by the low N level. Subsequently, a total of 514 metabolites were detected by non-targeted metabolomics analysis. There were 83 and 173 differential metabolites in the LL stress and control leaves and roots, respectively. Meanwhile, 54 and 67 differential metabolites were also detected in the leaves and roots under LN treatment and LN- treatment, respectively. The KEGG analysis showed that the LN- treatment significantly affected carbon and amino acid metabolism in tall fescue. Conversely, organic acids, amino acids, nucleic acids, and their respective derivatives were reduced in response to LL-induced stress. Furthermore, the LN- treatment enhanced the citrate cycle and increased the glucose and sucrose contents compared to the LN treatment. In addition, the asparagine level was significantly reduced in the leaves but significantly increased in the roots under LN- treatment. Thus, these results indicated that low N level increases photosynthesis by regulating the balance between carbon and N metabolism in the roots and leaves, thereby improving tolerance to LL-induced stress. • Low N improved activities of SPS, SS, GOGAT and GDH in tall fescue. • Low N up-regulated sugars, organic acids and amino acids in leaves. • Low N down-regulated sugars and amino acids in roots, but increased sucrose and Asn. • Low N increased contents of Asn in roots and Chl. • Low N regulated carbon and N metabolism, increased photosynthesis to improve LL tolerance.

Association of Serum Amylase Activity and the Copy Number Variation of AMY1/2A/2B with Metabolic Syndrome in Chinese Adults.

PurposeLow serum amylase activity and copy number (CN) variation (CNV) of the salivary amylase gene (AMY1) are reportedly associated with obesity and abnormal glucose metabolism; however, this association remains controversial. We aimed to clarify the relationship between serum amylase activity and the CNV of AMY1/2A/2B with the occurrence of metabolic syndrome (MetS) in Chinese adults.Patients and MethodsAnthropometry, metabolic risk factors, and serum amylase activity were assessed in 560 subjects (260 MetS patients; 300 healthy controls). AMY1/2A/2B CNs were evaluated using the highly sensitive droplet digital PCR.ResultsThe serum total, pancreatic, and salivary amylase activity, but not the AMY1/2A/2B CNs, was significantly lower in MetS patients than that in the control subjects. Patients <45 y had a lower AMY1 CN, compared to that in healthy controls. Low serum amylase activity was significantly associated with high MetS prevalence (p < 0.001). In the receiver operating characteristic curve analysis, serum amylase activity was a significant diagnostic indicator for MetS. The diagnostic value of total amylase was second only to that of γ-glutamyl transpeptidase; it was higher than that of alanine aminotransferase and uric acid.ConclusionLow serum amylase activity was significantly associated with increased risk of MetS in Chinese adults. Therefore, amylase could be a potential biomarker for predicting MetS.