Lipase Activity Research Articles

From sensing to acclimation: The role of membrane lipid remodeling in plant responses to low temperatures.

Low temperatures pose a dramatic challenge to plant viability. Chilling and freezing disrupt cellular processes, forcing metabolic adaptations reflected in alterations to membrane compositions. Understanding the mechanisms of plant cold tolerance is increasingly important due to anticipated increases in the frequency, severity, and duration of cold events. This review synthesizes current knowledge on the adaptive changes of membrane glycerolipids, sphingolipids, and phytosterols in response to cold stress. We delve into key mechanisms of low-temperature membrane remodeling, including acyl editing and headgroup exchange, lipase activity, and phytosterol abundance changes, focusing on their impact at the subcellular level. Furthermore, we tabulate and analyze current gycerolipidomic data from cold treatments of Arabidopsis, maize, and sorghum. This analysis highlights congruencies of lipid abundance changes in response to varying degrees of cold stress. Ultimately, this review aids in rationalizing observed lipid fluctuations and pinpoints key gaps in our current capacity to fully understand how plants orchestrate these membrane responses to cold stress.

Exploring the suitability of Hermetia illucens meal in Clarias magur catfish: effect on growth, physiology and flesh quality

Abstract The effect of substituting Hermetia illucens (HI) meal for fish meal (FM) on the growth performance, survival rate, feed utilization, digestive enzyme activity, immunological function, and flesh quality of Clarias magur (average weight = 3.3 ± 0.05 g) is investigated in this work. Four iso-nitrogenous diets with 35% crude protein were formulated, each with varying levels of HI substitution: HI25%, HI50%, HI75%, and HI100%, then compared to a control diet (HI0%). Following a 90-day experiment, it was observed that the growth performance and feed efficiency were significantly improved at the 50% level (). However, the control group exhibited greater levels of digestive enzymes, specifically protease and lipase activity. The fish’s health status remained unaffected by the substitution of fishmeal, while the 50% HI group showed significant improvements. The high levels of the antioxidant enzymes SOD and CAT, as well as the metabolic product MDA, suggested enhanced antioxidant activity in the groups that received HI inclusion. However, as the substitution level reached 100%, the quality of the flesh decreased, as indicated by increased lipid and adhesiveness, as well as decreased L* and WI (). The findings of the study suggest that HI larvae can replace FM in diet of C. magur. Overall, at 50% level of HI larvae meal inclusion in diet, better growth and immune function was evident, but it does lead to a decrease in flesh quality. This study enhances the existing knowledge on substituting fish meal with insect meal in catfish that are of regional importance. Additionally, it emphasizes the necessity for additional investigation to examine the underlying mechanisms employing biotechnological approaches.

Wild-Edible Allium Species from Highlands of Eastern Anatolia: Phytochemical Composition and In Vitro Biological Activities.

This study presents the phytochemical composition, antioxidant (hydrogen atom and single-atom transfer mechanisms), and digestive enzyme inhibitory (alpha-amylase, alpha-glucosidase, and pancreatic lipase) activities of ethanol-based extractions and traditional preparations (infusion) of the leaves of wild-edible Allium species (A. kharputense, A. affine, A. shirnakiense, and A. akaka) from the highlands of Eastern Anatolia. Among the eight extracts analyzed, ethanol extractions of the A. kharputense and A. akaka leaves exhibited better biotherapeutic activities and had the highest bioactive content. The dominant bioactive profile was composed of mainly allicin and phenolic compounds (chlorogenic acid, hesperidin, rutin, isoquercitrin, and quercetin) with small amounts of fatty acids. These data were similar to the biological activities and chemical composition of common Allium species and suggest the utilization of the extracts of wild-edible Allium species in the development of Allium-based biotherapeutics or nutraceuticals.

Effect of casein bioactive peptides on performance, nutrient digestibility, enzyme activity and intestinal microbial population in broiler chickens.

This experiment was carried out to investigate the effect of bioactive peptides derived from casein on performance, nutrient digestibility, enzyme activity and intestinal microbial population in broiler chickens. In this study, 350 1-day-old male Ross 308 broiler chicks were distributed among 35 pens in a completely randomized design with seven treatments, five replicates and 10 chicks in each replicate. The experimental treatments included: basal diet without any additives (control), basal diet + Avilamycin antibiotic, basal diet + 200, 400, 600, 800 and 1000 mg of peptides per kg of diet. Results showed no significant effects of the experimental treatments on weight gain and feed conversion ratio during the starter period, but there was a significant improvement in weight gain in grower, finisher and whole periods in chicks fed with diet containing 1000 mg/kg peptides (p < 0.05). Adding peptides improved intestinal morphology (in duodenum and ileum) (p < 0.05). Supplementation of casein peptides significantly reduced thiobarbituric acid reactive substances concentration in breast and thigh meat. The activity of amylase, lipase and protease enzymes improved in treatments containing 800 and 1000 mg peptides in comparison to the control treatment. The use of casein-peptides increased intestinal Lactobacillus and decreased Coliform populations.

Carp growth, body composition, lipidomics, and flesh quality in response to replacing dietary fish meal with a complex protein source

Alternatives to fish meal (FM) in fish feed are urgently required in aquaculture. We therefore examined the effect of replacing FM with a complex protein source (CPS) comprising soybean meal, peanut meal, corn protein meal, feather meal, and yeast protein, on carp (Cyprinus carpio) growth, body composition, lipidomics, and flesh quality. Lipidomics analysis was conducted to reveal the impact of dietary changes on fish lipid composition and metabolism, which is closely related to flesh quality and nutritional value. Over an eight-week growth trial, fish meal was replaced with CPS at 0 % (FM only), 20 %, 40 %, 60 %, 80 %, or 100 %. Weight gain and other growth parameters did not differ significantly among the treatments. Lipid deposition (LD) was positively correlated, and protein deposition negatively correlated, with CPS levels. LD and fillet ether extract were significantly elevated at 100 % CPS, whereas superoxidase dismutase expression, claudin-1 expression, and lipase activity were significantly reduced. The n-3 PUFA level and n-3/n-6 PUFA ratio were significantly lower following CPS feeding, reducing flesh quality. These findings indicate that CPS successfully replaced 60–80 % of dietary FM in carp diets, while the 100 % replacement group provided insights into the comprehensive effects of total substitution. Future studies will further optimize formulations based on these results to resemble practical production more closely. CPS with nutrient supplementation may therefore present a viable and safe partial replacement for dietary FM.

Hypolipidemic effect of polysaccharide from Sargassum fusiforme and its ultrasonic degraded polysaccharide on zebrafish fed high-fat diet

Sargassum fusiforme is a brown seaweed that grows abundantly along the rocky coastlines of Asian countries. The polysaccharides derived from Sargassum fusiforme (SFPS) have received much interest due to their various bioactivities, such as hypolipidemic, hypoglycemic, and antioxidant activities. In this study, we extracted and purified SFPS, and obtained the ultrasonic degradation product (SFPSUD). The lipid regulatory effects of SFPS and SFPSUD were investigated in a zebrafish model fed a high-fat diet. The results showed that SFPS significantly decreased the levels of total cholesterol (TC) and triglycerides (TG), and increased the activities of lipoprotein lipase (LPL) and hepatic lipase (HL). SFPSUD was more effective than the SFPS in reducing the TC and TG levels in zebrafish, as well as increasing the LPL and HL activities. Histopathological observations of zebrafish livers showed that SFPSUD significantly improved lipid metabolism disorder in the hepatocytes. The possible lipid-lowering mechanism in zebrafish associated with SFPS and SFPSUD may involve acceleration of the lipid metabolism rate by increasing the activities of LPL and HL. Thus, SFPSUD could be tested as a highly effective hypolipidemic drug. Our results suggest that SFPS and SFPSUD have potential uses as functional foods for the prevention and treatment of hyperlipidemia. Ultrasound can be effectively applied to degrade SFPS to improve its physicochemical properties and bioactivities.

The effect of various dietary MUFA content and n-6/n-3 ratios on rainbow trout (Oncorhynchus mykiss) fed on a whole plant protein based diet: growth performance, digestive enzymes activity, intestinal morphometry and fatty acids profile of muscle and liver.

The effect of diets with various dietary MUFA content and n-6/n-3 ratios, diets 1 (55.33, 1.00), 2 (25.30, 1.00), 3 (55.13, 2.05), 4 (24.92, 2.03), 5 (54.94, 8.06) and 6 (24.91, 8.06) and a control diet with fish oil (FO), diet 7 (33.60, 5.97), was studied on growth and digestive physiology of rainbow trout, Oncorhynchus mykiss. Juveniles, 14.65g ± 0.17, were fed the experimental diets for eight weeks. Those fish fed diet 1 (55.33, 1.00) had the lowest growth and nutritional indices, while fish fed diet 6 (24.91, 8.06) possessed the highest indices. However, fish fed D7 (33.60, 5.97) was intermediate in this regard. Proximate body composition results revealed no significant differences among various experimental groups (P > 0.05). Fish fed on diet 1 possessed the highest alkaline protease activity, while fish raised on diet 2 showed the lowest enzyme activity (P < 0.05). Fish fed on diets 1, 3 and 4 had the highest lipase activity (P > 0.05). Amylase activity and intestinal parameters did not differ among groups (P > 0.05). MUFA contents of liver and muscle reflected the MUFA contents of the diets; however, liver PUFA contents was not affected by dietary PUFA contents (P < 0.05). However, 18:3n-3 contents of liver decreased as dietary n-6/n-3 ratio increased (P < 0.05). Furthermore, the liver 20:4n-6 contents considerably increased as dietary n-6/n-3 increased to 8.06 (P < 0.05). Muscle 22:6n-3 content of groups 1 to 6 was lower than group 7 (P < 0.05). In conclusion, rainbow trout was considerably capable of de novo synthesis of 22:6n-3. Meanwhile, increasing dietary n-6/n-3 ratio to 8.06 decreased the muscle 22:6n-3 content which requires further considerations regarding fish immune competence and nutritional quality for human consumption.

Response of growth and physiological enzyme activities in Eriogyna pyretorum to various host plants.

Morphological attributes and chemical composition of host plants shape growth and development of phytophagous insects via influences on their behavior and physiological processes. This research delves into the relationship between Eriogyna pyretorum and various host plants through studuying how feeding on different host tree species affect growth, development, and physiological enzyme activities. We examined E. pyretorum response to three distinct host plants: Camphora officinarum, Liquidambar formosana and Pterocarya stenoptera. Notably, larvae feeding on C. officinarum and L. formosana displayed accelerated development, increased pupal length, and higher survival rates compared to those on P. stenoptera. This underlines the pivotal role of host plant selection in shaping the E. pyretorum's life cycle. The activities of a-amylase, lipase and protective enzymes were the highest in larvae fed on the most suitable host L.formosana which indicated that the increase of these enzyme activities was closely related to growth and development. Furthermore, our investigation revealed a relationship between enzymatic activities and host plants. Digestive enzymes, protective enzymes, and detoxifying enzymes exhibited substantial variations contingent upon the ingested host plant. Moreover, the total phenolics content in the host plant leaves manifested a noteworthy positive correlation with catalase and lipase activities. In contrast, a marked negative correlation emerged with glutathione S-transferase and α-amylase activities. The total developmental duration of larvae exhibited a significant positive correlation with the activities of GST and CarE. The survival rate of larvae showed a significant positive correlation with CYP450. These observations underscore the insect's remarkable adaptability in orchestrating metabolic processes in accordance with available nutritional resources. This study highlights the interplay between E.pyretorum and its host plants, offering novel insights into how different vegetation types influence growth, development, and physiological responses. These findings contribute to a deeper comprehension of insect-plant interactions, with potential applications in pest management and ecological conservation.

Methionine Source and Level Modulate Gut pH, Amino Acid Transporters and Metabolism Related Genes in Broiler Chickens.

This study determined the effects of two methionine (Met) sources at three total sulfur amino acids (TSAA) to lysine ratios (TSAA/Lys) on gut pH, digestive enzyme activity, amino acid transporter expression, and Met metabolism of broilers. The birds were randomly assigned to a 2 × 3 factorial arrangement with Met sources (dl-Met and dl-2-hydroxy-4-(methylthio)-butanoic acid (OH-Met)) and TSAA/Lys (0.58, 0.73, and 0.88) from 1 to 21 days. The results demonstrated that dl-Met and OH-Met supported the same growth performance, but high TSAA/Lys ratio reduced the feed intake and body weight (P < 0.05). OH-Met reduced the crop chyme pH and enhanced the jejunal lipase activity (P < 0.05). ATB0,+ expression decreased with increased dl-Met levels in the duodenum; the low TSAA/Lys ratio induced a stronger mRNA expression of basolateral Met transporters. OH-Met resulted in an increase of cystathionine β-synthase expression in the liver and a decrease in serum homocysteine levels at middle TSAA/Lys ratio compared with dl-Met treatment (P < 0.05). In conclusion, two Met sources support the same growth, but OH-Met acidified the crop chyme. The investigated transporter transcripts differed significantly along the small intestine. At the middle TSAA/Lys ratio, OH-Met showed a higher metabolic tendency of the trans-sulfuration pathway compared with dl-Met.

Feasibility evaluation of cottonseed protein concentrate to replace soybean meal in the diet of juvenile grass carp (Ctenopharyngodon idellus): Growth performance, antioxidant capacity, intestinal health and microflora composition

An investigation into the replacement of soybean meal (SBM) with cottonseed protein concentrate (CPC) in the diet of grass carp feed (Ctenopharyngodon idellus) was carried out. During a 56-day feeding trial, 750 grass carp were fed five experimental diets (isonitrogenous and isolipidic) with different levels of CPC: SBM (control group), CPC25, CPC50, CPC75, and CPC100, corresponding to dietary SBM replacements levels of 0%, 25%, 50%, 75%, and 100%. The results showed that dietary CPC inclusion significantly increased FW, WGR, and PER (P < 0.05) except CPC100 groups, which did not differ with SBM group (P > 0.05). FCR was remarkably increased when SBM replacement levels reached up to 100% (P < 0.05). Based on broken-line regression analysis of WGR against the dietary replacement of SBM with CPC, the optimal replacement level of SBM with CPC was estimated to be 75.11% for juvenile grass carp. Muscle texture parameters hardness, gumminess and chewiness were apparently elevated (P < 0.05), demonstrated an improved flesh quality followed CPC added. The CPC inclusion groups showed significantly higher serum IgM, C3 amd C4 contents, as well as ACP and AKP activities than SBM group except CPC100 groups (P < 0.05). The hepatic antioxidant capacity was enhanced followed CPC inclusion verified at enzymatic and transcriptional levels (P < 0.05). The intestinal inflammation was relieved evidenced by the down-regulated il-β, il-6 and tnf-α expressive abundance mediated through NF-κB pathway (P < 0.05). Additionally, the intestinal mucosal barrier function was enhanced by the up-regulation of tight junction proteins (occludin, claudin12, zo-1, and zo-2). The intestinal lipase and trypsin activities in CPC50 and CPC75 and intestinal folds height in CPC25, CPC50 and CPC75 were advanced (P < 0.05). The gut microbiota revealed no significant differences in the alpha diversity indices across treatments (P > 0.05). While the key bacteria of Aeromonas in the CPC100 group was increased leading intestinal dysbacteriosis. Besides, the ME1 of the microbial network has a negative correlation with pro-inflammatory gens and a positive correlation with antioxidant gens and tight linking proteins (P < 0.05). Summarily, CPC could partially replace SBM with positive influences on growth, antioxidant capacity, immunity, and intestinal microbiota in grass carp.

Optimization of Classical Lipase Activity Assays for Fish Digestive Tract Samples

Fish possess lipases from embryonic development to adulthood. Lipase activity methods vary and significantly differ in terms of the concentration of the substrate used, bile salt, Ca2+, temperature, pH, and type of lipase units, which limits comparative studies. The three most-used substrates are p-nitrophenyl (p-NP), β-naphthyl (β-N) derivates, and emulsified natural oils. These were selected to be redesigned in this study to measure lipase activity under temperature, pH, ion, and bile salt conditions closer to fish physiology, using the appropriate molar absorption coefficient to calculate the lipase units. Cynoscion parvipinnis (CP), Seriola rivoliana (SR), Centropomus viridis (CV), Elop affinis (EA), and Canthidermis maculate (CM) pyloric caeca-intestine extracts were studied. Sodium taurocholate showed the highest activity for intestinal lipases, and the fatty acid length in the substrates changed the lipase hydrolysis rate. The highest lipase activity was obtained with p-NP butyrate and p-NP caprylate in four fish species. Lipase activity was highly activated with Ca2+ (4–7 mM). The β-N absorption spectrum indicates a plateau between 534 and 554 nm for fish lipases. Salmon oil was identified as the most digestible lipid in the four fish species using the in vitro digestibility assay. The lipase zymogram showed an apparent size of 46.3 kDa for CP, 40.2 kDa for SR, 46.2 kDa for CM, 106.6 kDa for EA, and 58.3, 84.6, and 162.1 kDa for CV.

UPLC-QTOF-MS characterized, herbal medicine, pancogrit modulates NF-κB and JAK2/STAT3 signaling pathways in cell-based model of TNF-α dependent acute pancreatitis

Acute pancreatitis develops as a local inflammatory condition of the pancreas due to a wide range of factors including overdose of alcohol or drugs, gall stones, etc. At present, medications based on herbal formulations have gained importance due to their better safety profile. Current study assessed the pharmacological effects of Pancogrit, an herbal medicine, in caerulein and TNF-α-induced in vitro pancreatitis models. A comprehensive evaluation of phytometabolites present in Pancogrit was conducted and 85 phytometabolites were identified through UPLC-QTOF-MS and UPLC-UV. The bioactivity and mode of action of Pancogrit were assessed in caerulein-induced AR42J (rat pancreatic acinar) cells, TNF-α-induced PANC-1 (human pancreatic duct) cells, and NF-κB reporter cells. Pancogrit was found to decrease the elevated amylase and lipase activity in caerulein-induced AR42J cells. It ameliorated the increased ROS levels, IL-6, IL-8 release and NF-κB activity in TNF-α-induced PANC-1 and NF-κB reporter cells. Pancogrit also downregulated IL-6, IL-1β, ICAM-1, and STAT3 gene expression in PANC-1 cells. Moreover, Pancogrit inhibited the protein expression levels of phosphorylated STAT3, phosphorylated and total JAK2 in TNF-α-induced PANC-1 cells. Taken together, Pancogrit is a clinically relevant therapeutic agent for mitigation of pancreatitis.

Effects of Ultra-High-Pressure Treatment on Chemical Composition and Biological Activities of Free, Esterified and Bound Phenolics from Phyllanthus emblica L. Fruits.

Phyllanthus emblica L. fruits (PEFs) were processed by ultra-pressure (UHP) treatment and then extracted by the ultrasonic-assisted extraction method. The influence of UHP on the phenolic composition, enzyme inhibitory activity and antioxidant activity of the free, esterified, and bound phenolic fractions from PEFs were compared. UHP pretreatment of PEFs significantly increased the total phenolic and flavonoid contents (p < 0.05). A total of 24 chemical compositions were characterized in normal and UHP-treated PEFs by UHPLC-ESI-HRMS/MS. Compared with normal PEFs, these three different phenolic fractions had stronger antioxidant activities and inhibitory effects on the intracellular reactive oxygen species (ROS) production in H2O2-induced HepG2 cells (p < 0.05). The ROS inhibition might be due to an up-regulation of the expressions of superoxide dismutase (SOD) and glutathione (GSH) activities. In addition, these three different phenolic fractions also significantly inhibited the activities of metabolic enzymes, including α-glucosidase, α-amylase and pancreatic lipase. This work may provide some insights into the potential economics and applications of PEFs in food and nutraceutical industries.

Insecticidal, physiological, and biochemical effects of Schinus molle essential oil on the adults of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae)

Rhyzopertha dominica (F.) is considered as a major stored product pest. Conventional insecticides induce adverse effects on the environment. Plant derivative products constitute a promising alternative for pest control. The purpose of our research was to identify the chemical profile of essential oil (EO) extracted from Schinus molle L. (Anacardiaceae) and to evaluate the fumigant and the contact toxicity, and the repellent activity of this oil on adults of Rhyzopertha dominica F. (Coleoptera), a major pest in products that are stored around the world. The effects of this oil were examined on biochemical profile (energy reserves and Proteins), selective biomarkers like acetylcholinesterase (AChE), glutathione S-transferases (GST) and glutathione (GSH), and nucleic acids (DNA and RNA). Digestive enzymes were also investigated. The major chemical compounds identified by the GC-MS were α-phellandrene (16.613%), ß-phellandrene (12.104%), elemol (9.028%) and β-eudesmol (5.872%). Then, we evaluated the repellent activity, and also the effects in nutritional reserves and some biomarkers. This EO exhibited an insecticidal and repellent activity as a function of the exposure time and concentrations. Contact (LC50 at 24 h: 19.99 μL/mL) is the most effective mode of application compared to fumigation (LC50 at 24h: 174.30 μL/L air). S. molle EO was also investigated in digestive enzymes’ activities (α-amylase, lipase, chitinase and protease). Our results revealed a decrease in both α-amylase, lipase, protease and chitinase activities in treated adults compared to controls. In addition, we noticed a neurotoxic activity of S. molle EO traduced by a decrease of AChE. An induction of the detoxification system was observed via a decrease in GSH rate and an increase in GST activity. Moreover, the treatment induces an alteration of biochemical profile of R. dominica adults. Lastly, essential oil was examined on nucleic acids. Results showed an increase in DNA and RNA amount in treated adults when compared with control. Due to their effective source of bioactive compounds, the EO from the studied plant could be used as an alternative strategy for the management of stored product pests.

Moisture content in diets in the co-feeding phase of Pseudoplatystoma sp. influences performance and digestive process.

Live food in the initial life stages of neotropical fish is essential for their development and health; however, it can significantly increase production costs. This study uses complete diets with varying moisture contents (47%, 35%, 24%, and 8%) as a cost-effective alternative in the co-feeding phase of surubim larvae, assessing their influence on development, digestive enzymes, and liver metabolism. In a completely randomized design, 3200 three-day-old Pseudoplatystoma sp. larvae (0.001g) were distributed evenly among 16 aquariums (20L), with 200 individuals per aquarium. For the first five days, all larvae were fed Artemia exclusively, after which they were fed experimental diets with varying levels of humidity (47%, 35%, 24%, and 8%) six times a day across four treatments and four replicates. The 21-day feeding trial demonstrated that larvae fed with 24% and 8% moisture diets exhibited increased (p < 0.05) weight gain, final length, and protein efficiency rate. The remaining growth parameters (i.e., specific growth rate and condition factor) did not show significant differences (p > 0.05) among the dietary treatments. Enzymatic analysis revealed that the 47% moisture diet enhanced the amylase and alkaline phosphatase activities, whereas the 24% and 35% moisture diets elevated the lipase and protease activities. The 47% moisture diet also resulted in increased alanine aminotransferase, aspartate aminotransferase, and albumin levels, along with visible hepatic histopathologies in samples, such as visible lipid vacuoles, displacement of the nucleus of the hepatocyte, and increased sinusoid spaces. No significant liver changes were observed in fish fed with other diets. Principal component analysis showed that diets with 8-24% moisture content were the most beneficial during the co-feeding phase of surubim larviculture.

Intra-cohort cannibalism and aggressive behavior in tropical gar (Atractosteus tropicus) larvae: Effects of stocking density and starvation

Cannibalism in early fish developmental stages is a biological phenomenon affecting aquaculture, so seeding density and feeding schemes play a fundamental role in its optimal control. The objective of this research was to evaluate two initial stocking densities, 0.7 larvae/L (D7) and 1.4 larvae/L (D14), which were fed (F) and not fed (NF) in tropical gar (Atractosteus tropicus) larvae on growth, attacks, survival, and digestive enzyme activity, digestive morphology, and oxidative enzymes and aggressiveness gene expression. A total of 420 larvae (0.022 ± 0.003 g; 1.52 ± 0.10 cm) were placed in 70 L tanks connected to a recirculation system. Treatment F larvae were fed a formulated food. D14F larvae had the highest final weight, total length, and specific growth rate (SGR) (p < 0.05). The highest survival percentage was in D7F larvae (46.19 ± 2.74) (p < 0.05). The highest frequency of attacks occurred in D14F larvae (26.66 ± 0.82) (p < 0.05). The coefficient of variation (CV) and size heterogeneity (SH) were higher in D7F larvae (13.56 ± 1.80; 0.81 ± 0.10) (p < 0.05). The F larvae started attacks at 8 days after hatching (DAH), while the NF larvae showed it at 10 DAH. The difference in weight between the attacker and the attacked was 16.44 ± 9.75% and in total length 12.28 ± 4.57% (p < 0.05). Acid and alkaline protease, trypsin, and lipase activities presented differences between both factors, as well as the interaction between them. D14F larvae presented the highest Glutathione peroxidase (GPX) activity (p < 0.05), while D7-NF larvae registered the highest catalase (CAT) activity (p < 0.05). Superoxide dismutase (SOD) activities only showed differences between F and NF larvae (p < 0.05). The liver presented the highest percentage of area with melanomacrophage centers (MMC) in D7-NF larvae, and hepatocytes with the highest area were recorded in D14F larvae (p < 0.05). In gut, the highest enterocytes were recorded in D14F larvae (p < 0.05). cat, cck, and gpx expression did not show difference between feeding regimes. The expression of sod1 and sod2 in D7F and D14F treatments presented the highest expressions (p < 0.05). D7F larvae presented higher expression of avp1, crh, htr1, sstr1, th and tph1 genes (p < 0.05). Our results show that A. tropicus larvae D14F presented the highest growth and morphometric parameters and decreased CV and SH, which shows a more homogeneous growth. Regarding cannibalism, fed larvae (D7F, D14F) presented cannibalism in a greater proportion than unfed larvae regardless of density, however, it is necessary to analyze other physiological and social factors that could be related to the aggressiveness and cannibalism of the species.

Rancidity development in oat during industrial processing

To improve the shelf-life of food products rich in lipids, it is important to minimize the lipid oxidation that occurs during processing, since this oxidation not only decreases shelf-life but also induces off-flavors. To evaluate the oxidation of lipids in the production of one β-glucan-rich and one protein-rich food supplement made from oats (Avena sativa), the neutral and polar lipid profile, hexanal content, peroxide value, avenanthramides and lipase activity were measured at all production steps. The concentration of antioxidants in the form of avenanthramides was also investigated. This study shows that oat lipases were fully inactivated in the wet processing part of the processing line, and the total lipid content per dry weight increased with the progression of steps toward the oat protein product. Processing had no apparent effect on avenanthramide levels. Lipid oxidation markers increased in certain processing steps. The most significant increase in hexanal and peroxide values could be seen in the spray-drying step of the process, while a much smaller increase was seen for the drum-drying. The main conclusion is that the most important factor to prolong the shelf-life of the product is to minimize the oxidation in the drying step.

Effects of selenomethionine on the growth, oxidative potential, digestive enzyme activity, and immune status of juvenile sterlet (Acipenser ruthenus)

Abstract In a 56-day experiment, the effects of selenium-enriched yeast (SeY) on the growth, enzymatic activity of the gastrointestinal tract, oxidative stress parameters, and selected immunological parameters of sterlet, Acipenser ruthenus (L.), were analyzed. The concentration of selenomethionine (SeMet) from SeY in the feed was 0 mg kg−1 (C), 0.7 mg kg−1 feed (S1), 1.4 mg kg−1 feed (S2), and 2.1 mg kg−1 feed (S3). Statistically significant differences were found in the final fish body weight between the control and groups S1 and S3. A significant increase in lipase activity was found in the initial section of the small intestine of fish from group S3. The highest activity of the antioxidant enzymes glutathione peroxidase and superoxide dismutase was recorded in the liver of fish from group S2. Analyses of non-specific humoral response parameters showed an increase in ceruloplasmin activity in group S1. The lowest active dose of SeMet derived from yeast tested in this study that stimulated humoral immunity and fish growth was 0.7 mg kg−1 feed (S1).

Serum DGGR lipase activity in equids with gastrointestinal disease

Serum <scp>DGGR</scp> lipase activity in equids with gastrointestinal disease

Effects of dietary Pediocuccus pentosaceus and/or ferulic acid on performance, digestive enzymes, blood biochemistry, and growth-related genes expression in rainbow trout (Oncorhynchus mykiss)

This study investigated the effects of dietary Pediocuccus pentosaceus (PP) and/or ferulic acid (FA) on the performance, digestive enzymes, and growth-related genes expression in rainbow trout (Oncorhynchus mykiss). Fish (94.30 ± 1.77 g) were fed on the control diet (T0), 108 CFU/g of PP probiotic (T1), 100 mg/kg of FA (T2), and a combination of PP and FA (T3) for 8 weeks. The present results indicated that rainbow trout fed with PP and/or FA showed better final weight, weight gain, and feed conversion ratio than the control group (P < 0.05). The activities of trypsin and chymotrypsin were higher in T2 and T3 than in the control group (P < 0.05). Meanwhile activities protease and alpha-amylase were highest in T2, lipase activity was highest in T3. Compared to the control group, total protein, total antioxidant activity, and cholesterol levels were significantly (P < 0.05) higher in T2 and T3 with no significant (P > 0.05) differences between them. Supplemented diets with FA and/or PP decreased markedly (P < 0.05) triglycerides levels and its lowest levels were obtained in T2 and T3 with no significant (P > 0.05) differences between them. The relative expression levels of GHRL and GHr genes were significantly higher in the treatments fed with FA and/or PP (T1 – T3) than those in the control group (P < 0.05). Highest upregulation of IGF-1, and IGF-II gens were detected in T2 and T3 with no significant (P > 0.05) differences between them. In conclusion, it was shown that both dietary supplements have the potential role to enhance the performance, digestive enzymes, and growth related-genes expression in rainbow trout. Feeding fish on FA-enriched diets showed superior enhancements than that fed on the PP diet only.