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Effects of dietary supplementation of comfrey polysaccharides (CPs) on production performance, egg quality, and microbial composition of cecum in laying hens were evaluated. A total of 240 laying hens were allocated into 4 groups with 6 replicates per group. The laying hens were fed diets containing CPs at levels of 0, 0.5, 1.0, and 1.5 %, respectively. The results showed that the egg production rate increased by 5.97 %, the egg mass improved by 6.71 %, and the feed conversion rate reduced by 5.43 % in the 1.0 % supplementation group of CPs compared with those in the control group. The digestibility of ash, crude fat, and phosphorus was notably improved by the addition of CPs at 1.0 % (P 0.05). The relative abundances of Bacteroidetes at the phylum level, Bacteroidaceae, Rikenellaceae, and Prevotellaceae at the family level were increased by CPs (P 0.05). The relative abundances of Bacteroides, Megamonas, Rikenellaceae_RC9_gut_group, [Ruminococcus]_torques_group, Methanobrevibacter, Desulfovibrio, Romboutsia, Alistipes, and Intestinimonas at the genus level were increased by CPs (P 0.05). Dietary supplementation of CPs could enhance the production performance of laying hens, which might be related to the improvement of nutrient digestibility and microbial community modulations in the cecum. Therefore, CPs have potential application value as prebiotics in laying hens.

This study aimed to explore the optimum conditions for the ultrasonic-enzyme-assisted extraction of comfrey (Symphytum officinale L.) polysaccharides (SOP) by the response surface methodology (RSM). The optimum extraction conditions included an extraction time of 62 min, an enzyme complex dose of 1.1 %, a liquid-to-solid ratio of 21 mL/g, and a pH value of 6. A SOP yield of 20.32 % was achieved. The digestion and fermentation behaviors of SOP in vitro were determined. A digestion test was performed in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). A fermentation model was prepared with the cecal contents of chickens. The results showed that SGF (2.15 ± 0.09 %) and SIF (1.08 ± 0.06 %) were ineffective in the digestion of SOP. During fermentation, the pH values of the culture medium were lower than the initial pH (7.75 ± 0.03). SOP (47.06 ± 1.79 %) was used by the chicken cecal microbiota, which produced 34.12 ± 0.79 mg/mL short-chain fatty acids at 48 h. Moreover, the composition of the chicken cecal microbiota could be regulated by SOP during fermentation. The relative abundance of Lactobacillus at the genus level was improved. Therefore, SOP might have the potential to serve as a prebiotic in chicken production.

The continuous ovulation of laying hens during the peak period is likely to cause oxidative stress, resulting in a reduction in the laying cycle over time. The aim of this study was to evaluate the antioxidant effects of

Alfalfa (Medicago sativa L.) polysaccharides (MSPs) were subjected to three drying methods, namely, hot-air drying (HD), freeze drying (FD), and vacuum drying (VD). Three corresponding polysaccharides were obtained and named HD-MSPs, FD-MSPs, and VD-MSPs. The physicochemical characteristics and activities of the three MSPs were compared. The results showed that the three MSPs all consisted of five monosaccharides: glucuronic acid, rhamnose, glucose, galactose, and xylose. However, the glucuronic acid contents of HD-MSPs (7.90 %) and VD-MSPs (9.94 %) were lower than that of FD-MSPs (11.65 %). HD-MSPs and VD-MSPs had higher molecular weights than that of FD-MSPs. HD-MSPs possessed higher inhibition activities against α-amylase and α-glucosidase than VD-MSPs and FD-MSPs, which might be due to their relatively higher viscosities and molecular weights. The scavenging activities of FD-MSPs for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and 2,2-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radicals were the highest among those of the three MSPs, which might be related to their lower molecular weight and higher content of uronic acid. These results suggested that MSPs obtained by different drying methods possessed different specific characteristics and had the potential to be used for different purposes, where HD-MSPs and FD-MSPs had the potential to be used as a hypoglycemic agent and an antioxidant, respectively.

The optimum extraction conditions of polysaccharides from roxburgh rose (Rosa roxburghii Tratt.) leaves (RLP) were obtained by response surface methodology (RSM), which were a liquid to solid ratio of 21.16 mL/g, an extraction temperature of 81.32 °C, and an extraction time of 90.49 min. An RLP yield of 11.04% was obtained under these conditions. DEAE-52 cellulose and Sepharose CL-6B columns were used to purify the RLP, and the purified polysaccharide components RLP-1.2 and RLP-2.1 were obtained. Both RLP-1.2 and RLP-2.1 were composed of galacturonic acid (GalA), glucose (Glc), galactose (Gal), and arabinose (Ara). However, the molar ratios of GalA, Glc, Gal, and Ara in RLP-1.2 and RLP-2.1 were different. At a concentration of 10 mg/mL, the α-amylase inhibitory activities of RLP-1.2 and RLP-2.1 reached 80.74% and 89.85% that of acarbose, respectively, and the α-glucosidase inhibitory activity of RLP-1.2 reached 87.91% that of acarbose. In addition, both RLP-1.2 and RLP-2.1 showed good antioxidant activity. These results suggested that RLP-1.2 and RLP-2.1 possess potential as natural hypoglycemic agents or natural antioxidants.

Egg production performance, egg quality, nutrient digestibility, and microbial composition as affected by dietary inulin supplementation were evaluated in laying hens. A total of 300 laying hens were divided into 5 groups and fed diets containing inulin at levels of 0 (control), 5, 10, 15 and 20 g/kg, respectively. The results showed that the 15 g/kg inulin supplementation level improved average egg weight by 2.54%, egg mass by 5.76%, and laying rate by 3.09%, and decreased the feed conversion ratio by 3.61% compared to those of the control during feeding weeks 1 to 8. Dietary inulin supplementation improved eggshell thickness, nutrient digestibility and cecum Bacteroidales_S24-7_ group abundance in the laying hens. In conclusion, dietary inulin supplementation, particularly at the level of 15 g/kg, improved the egg production performance and eggshell thickness of laying hens, mainly due to increased nutrient digestibility and selective modulations of the cecum microbial communities.

The effects of inulin supplementation in the diet of laying hens on the antioxidant capacity of refrigerated (0, 2, 4, 6 and 8 weeks) eggs were evaluated. Three hundred commercial laying hens were divided into five treatment groups and fed diets with supplements of 0 (control), 5, 10, 15 or 20 g/kg inulin. The experimental results showed that the use of inulin (15 or 20 g/kg) in the diet for laying hens increased the DPPH and ABTS radical-scavenging activities, total phenolic content and ferric reducing power in the yolks of fresh (stored 0 weeks) and stored eggs (P

The optimum enzyme-assisted extraction conditions of cup plant (Silphium perfoliatum L.) polysaccharides (CPP) were obtained by response surface methodology (RSM), and were found to be an enzymatic hydrolysis time of 66 min, a liquid-solid ratio of 22 mL/g, pH 5.1, and an enzyme-complex dosage of 1.59 %, allowing a CPP yield of 13.69 %. DEAE-52 cellulose and Sepharose CL-6B columns were used to purify the CPP. A purified polysaccharide component, CPP-1.2, was obtained and further analyzed for its characteristics, antioxidant properties, and hypoglycemic activity. The monosaccharide composition of CPP-1.2 was mannose, galacturonic acid, glucose, galactose, and arabinose with a molar percentage ratio of 2.24:16.34:44.17:24.28:12.97. The 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2-Azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities of CPP-1.2 (1.0 mg/mL) reached 95.20 % and 93.69 % that of ascorbic acid (1.0 mg/mL), respectively. Moreover, CPP-1.2 presented significantly higher inhibitory properties on the activities of α-amylase and α-glucosidase than acarbose at each concentration tested. These results suggest that CPP-1.2 possesses the potential to be used as an antioxidant and hypoglycemic agent.

Hot water extraction was applied to extract red clover (Trifolium pratense L.) polysaccharides (RCP) and the extraction conditions were optimized using the response surface methodology (RSM). An RCP yield of 12.72 ± 0.14% was achieved under the optimum extraction conditions: extracting time of 95 min, extracting temperature of 93 °C, and solvent-material ratio of 21 mL/g. A component named RCP-1.1 with the molecular weight of 7528.81 kDa was purified from RCP. RCP-1.1 was composed of glucose, galacturonic acid, arabinose, and galactose, with molar percentages of 52.54, 1.04, 16.31, and 30.11%, respectively. At the determination concentration of 10 mg/mL, the α-glucosidase inhibition ability of RCP-1.1 reached 86.72% of that of acarbose. The scavenging rates of RCP-1.1 (3.0 mg/mL) for DPPH and ABTS radicals reached 91.82% and 98.95% of that of ascorbic acid (3.0 mg/mL), respectively. Based on these results, RCP-1.1 possesses the potential to be used as a natural hypoglycemic agent or an antioxidant.

The purpose of the present research was to compare the effects of four extraction methods on the extraction yields, physicochemical characteristics, and antioxidant activities of polysaccharides from the cup plant (Silphium perfoliatum L.) (CPPs). The extraction methods included the hot water extraction method (HEM), ultrasonic-assisted extraction method (UEM), enzyme-assisted extraction method (EEM), and the ultrasonic-enzyme-assisted extraction method (UEEM). Four corresponding CPP extracts, HEM-CPPs, UEM-CPPs, EEM-CPPs, and UEEM-CPPs, were obtained. The results indicated that there were notable differences between the extraction methods regarding the yield, average molecular weight, uronic acid content, monosaccharide proportions, and the antioxidant activities of the CPPs. HEM-CPPs were extracted with the lowest yield (6.44%). EEM-CPPs had the largest extraction yield (9.87%) and the most notable antioxidant abilities of ferric reducing power and free radical scavenging activity. According to correlation analysis, the higher antioxidant abilities of EEM-CPPs might be due to their smaller average molecular weight and a higher content of uronic acid than those of the other extracted CPPs. Therefore, EEM could serve as a promising technique for extracting CPPs.

Polysaccharides from alfalfa (Medicago sativa L., MSPs) were extracted by four different methods: hot-water extraction (HWE), ultrasonic-assisted extraction (UAE), enzyme-assisted extraction (EAE) and ultrasonic-enzyme-assisted extraction (UEAE). The experimental results showed that the monosaccharide compositions of the four MSPs extracted by the different extraction methods were the same, but the monosaccharide proportions were different. MSPs extracted by the UEAE method possessed the largest extraction yield, the highest uronic acid content and the best antioxidant activities among the four MSPs analysed. Additionally, the Plackett-Burman design (PBD) and response surface methodology (RSM) were used to determine the optimum UEAE conditions for extracting MSPs, revealing optimal conditions at a pH of 5.7, a 58 min enzymolysis time, a 40 °C enzymolysis temperature and a 41 °C ultrasonic temperature; an MSPs yield of 12.95% was obtained under these extraction conditions.

Tsunamis are catastrophic ocean waves that could cause devastating damage to human lives, properties, and coastal infrastructures. This article presents the design and sea test results of a deep-sea tsunami warning buoy system. The system consists of a seafloor tsunami detection subsystem and a surface buoy. The tsunami detection subsystem monitors the tsunami waves through seafloor water pressure measurement. Detection of tsunami waves is achieved by separating the influence of astronomical tidal waves from the seafloor measurements via a cubic polynomial extrapolation method. The deep seafloor measurements and the tsunami detection results are transmitted in real time from the seafloor subsystem to the surface buoy via underwater acoustic communications; the buoy then relays the data to an onshore tsunami warning center via satellite links. The tsunami warning buoy system was evaluated in four deep-sea tests at different locations. In the last sea test, the system achieved an effective working duration of 108 consecutive days. This article analyzes the causes of false alarms and data transmission failures in the sea tests and puts forward effective solutions for system improvement. The system design and the sea test results could serve as references for future development of deep-sea infrastructures.

The aim of this study was to assess the influences of extraction methods on the physicochemical characteristics and antioxidant activities of polysaccharides from Astragalus cicer L. (ACPs). Four methods were applied to ACPs extraction: hot water extraction (HW), ultrasonic-assisted extraction (UA), enzyme-assisted extraction (EA) and enzyme-ultrasonic-assisted extraction (EUA). The ACPs extracted by different techniques were correspondingly named HW-ACPs, UA-ACPs, EA-ACPs and EUA-ACPs. The results indicated that EA-ACPs had higher extraction yields (13.91%). The HPLC results showed that the monosaccharide contents of the four ACPs were significantly different. The ACPs presented antioxidant abilities in a concentration-dependent manner. The higher uronic acid content and smaller molecular weight of the EA-ACPs might contribute to the higher antioxidant activities of EA-ACPs among the four ACPs. These results indicated that enzyme-assisted technology can improve ACPs yields and obtain ACPs with higher antioxidant activities.

Comfrey (Symphytum officinale L.) has long been used in folk medicine due to its effects of anti-inflammatory and acesodyne. The present study was designed to evaluate the effects of extraction techniques on the physicochemical properties and activities of polysaccharides from comfrey root (CRPs). CRPs were extracted by using four methods including hot water extraction (HW), ultrasonic assistance extraction (UA), enzyme assistance extraction (EA) and enzyme-ultrasonic assistance extraction (EUA). The results showed that CRPs extracted by EUA method (EUA-CRPs) had the highest extraction yield of 24.51%. HPLC analysis presented that the monosaccharide compositions of the four CRPs were indentical, but the monosaccharide content was significantly different. EUA-CRPs had better antioxidant activity, which might be related to its smaller molecular weight and higher content of uronic acid. EUA-CRPs exhibited notable α-glucosidase inhibition activity. The results suggested that enzyme-ultrasonic assistance technology was a good way to extract polysaccharides from comfrey root.

The effects of extraction techniques on the physicochemical properties, antioxidant activity and antihyperglycemic activity of comfrey polysaccharides (CPs) were evaluated. Four techniques were used to extract CPs: hot water extraction (HW), ultrasonic-assisted extraction (UA), enzyme-assisted extraction (EA) and enzyme-ultrasonic-assisted extraction (EUA). Experimental results indicated that CPs extracted by the UA (UA-CPs) and EUA methods (EUA-CPs) had higher extraction yields. The four CPs showed the same monosaccharide composition but a significant difference in monosaccharide content. CPs showed antioxidant activities and antihyperglycemic activities in a concentration-dependent manner. UA-CPs exhibited better antioxidant capacity, which might have been related to its smaller molecular weight and higher uronic acid content. In addition, UA-CPs showed notable α-glucosidase inhibition activity. These results suggested that ultrasonic-assisted extraction technology was more beneficial to enhance the extraction yields of the polysaccharides, and obtain higher bioactive polysaccharides from comfrey.

Four different extraction methods, including hot water extraction (HWE), ultrasonic-assisted extraction (UAE), enzyme-assisted extraction (EAE) and ultrasonic-enzyme-assisted extraction (UEAE), were applied to extract polysaccharides from Trifolium repens L. (TRPs). In addition, response surface methodology (RSM) was performed to optimize the extraction conditions of TRPs. The results showed that different extraction methods had significant effects on the extraction yields and antioxidant activities of TRPs. TRPs extracted by the EAE method (10.57%) and UEAE method (10.62%) had significantly higher extraction yields than TRPs extracted by the HWE method (8.35%) and UAE method (9.43%) (P P > 0.05). TRPs extracted by the EAE method had a higher content of uronic acid and exhibited better antioxidant capacities. Therefore, EAE was selected as the optimal extraction method to extract TRPs. The optimal extraction conditions of EAE to extract TPRs were liquid–solid ratio 30 mL/g, enzymolysis time 87 min, enzyme-complex dosage 1.6% and pH 6, leading to a TRPs yield of 13.15%.

Performing the researches on extraction conditions, purification and activities of polysaccharides are of great significance to the development of comfrey (Symphytum officinale L.) resources. In this study, the optimum extraction conditions of polysaccharides from comfrey (CPs) were obtained by response surface methodology (RSM), which were liquid to solid ratio 25 mL/g, extraction temperature 89 °C, and extraction time 155 min. A CPs yield of 19.20 % was obtained under these conditions. DEAE-52 cellulose and Sepharose CL-6B columns were used to purify CPs, and the purified polysaccharide component CPs-1.2 was obtained. The characteristics, emulsifying property, and hypoglycemic activity of CPs-1.2 were analyzed. The monosaccharide compositions of CPs-1.2 were galacturonic acid, arabinose, glucose, and galactose with the molar ratio of 1.00:0.88:2.28:1.13. CPs-1.2 showed notable DPPH and ABTS radical scavenging abilities, which could reach 95.00 % and 96.71 % of those of ascorbic acid at the determination concentrations of 0.4 mg/mL and 1.5 mg/mL, respectively. The α-glucosidase inhibitory activity of CPs-1.2 (10 mg/mL) could reach 80.00 % of that of acarbose. In addition, CPs-1.2 showed good emulsifying properties for olive oil, benzene, xylene and methylbenzene. These results suggested that CPs possessed potential as a hypoglycemic agent, an antioxidant or a polysaccharide-based emulsifier.

The thermal inactivation kinetics of enzymes, including polyphenol oxidase (PPO) and peroxidase (POD), in chicory (Cichorium intybus L.) leaves were evaluated. In addition, the influences of different drying techniques (shade drying, hot air drying and freeze drying) on the phenolic profiles and antioxidant activities of chicory leaves were determined. The antioxidant activities of chicory leaves were evaluated on the basis of their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity. The results showed that the activation energy for PPO and POD inactivation were 123.00 kJ/mol and 78.99 kJ/mol, respectively. Preliminary treatment with hot water for 3 min at 90 °C was beneficial for preserving the phenolics present in fresh leaves. Hot air drying was better for the phenolics preservation. The hot air-dried and freeze-dried leaves possessed good antioxidant activities. The leaves with higher phenolics contents had better antioxidant activities, which indicated that the preservation of the phenolics was important for maintaining the antioxidant activity of chicory leaves.

This study was designed to investigate the extraction conditions of polysaccharides from comfrey (Symphytum officinale L.) root (CRPs) using response surface methodology (RSM). The effects of three variables including liquid-solid ratio, extraction time and extraction temperature on the extraction yield of CRPs were taken into consideration. Moreover, the effects of drying methods including hot air drying (HD), vacuum drying (VD) and freeze drying (FD) on the physicochemical properties and antioxidant activities of CRPs were evaluated. The optimal conditions to extract the polysaccharides were as follows: liquid-solid ratio (15mL/g), extraction time (74min), and extraction temperature (95°C), allowed a maximum polysaccharides yield of 22.87%. Different drying methods had significant effects on the physicochemical properties of CRPs such as the chemical composition (contents of total polysaccharides and uronic acid), relative viscosity, solubility and molecular weight. CRPs drying with FD method showed stronger reducing power and radical scavenging capacities against DPPH and ABTS radicals compared with CRPs drying with HD and VD methods. Therefore, freeze drying served as a good method for keeping the antioxidant activities of polysaccharides from comfrey root.