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Rapid advancements of genome sequencing (GS) technologies have enhanced our understanding of the relationship between genes and human disease. To incorporate genomic information into the practice of medicine, new processes for the analysis, reporting, and communication of GS data are needed. Blood samples were collected from adults with a PCR-confirmed SARS-CoV-2 (COVID-19) diagnosis (target N = 1500). GS was performed. Data were filtered and analyzed using custom pipelines and gene panels. We developed unique patient-facing materials, including an online intake survey, group counseling presentation, and consultation letters in addition to a comprehensive GS report. The final report includes results generated from GS data: (1) monogenic disease risks; (2) carrier status; (3) pharmacogenomic variants; (4) polygenic risk scores for common conditions; (5) HLA genotype; (6) genetic ancestry; (7) blood group; and, (8) COVID-19 viral lineage. Participants complete pre-test genetic counseling and confirm preferences for secondary findings before receiving results. Counseling and referrals are initiated for clinically significant findings. We developed a genetic counseling, reporting, and return of results framework that integrates GS information across multiple areas of human health, presenting possibilities for the clinical application of comprehensive GS data in healthy individuals.

Implementation of polygenic risk scores (PRS) may improve disease prevention and management but poses several challenges: the construction of clinically valid assays, interpretation for individual patients, and the development of clinical workflows and resources to support their use in patient care. For the ongoing Veterans Affairs Genomic Medicine at Veterans Affairs (GenoVA) Study we developed a clinical genotype array-based assay for six published PRS. We used data from 36,423 Mass General Brigham Biobank participants and adjustment for population structure to replicate known PRS–disease associations and published PRS thresholds for a disease odds ratio (OR) of 2 (ranging from 1.75 (95% CI: 1.57–1.95) for type 2 diabetes to 2.38 (95% CI: 2.07–2.73) for breast cancer). After confirming the high performance and robustness of the pipeline for use as a clinical assay for individual patients, we analyzed the first 227 prospective samples from the GenoVA Study and found that the frequency of PRS corresponding to published OR > 2 ranged from 13/227 (5.7%) for colorectal cancer to 23/150 (15.3%) for prostate cancer. In addition to the PRS laboratory report, we developed physician- and patient-oriented informational materials to support decision-making about PRS results. Our work illustrates the generalizable development of a clinical PRS assay for multiple conditions and the technical, reporting and clinical workflow challenges for implementing PRS information in the clinic.

With the accelerated pace of modern life, people are facing more and more health pressure. The study of polysaccharides seemed a good choice as a potential treasure trove. Polysaccharides, one of the four basic substances (proteins, nucleic acids, lipids and carbohydrates) that constitute life activities, are obviously an underrated macromolecular substance with great potential. Compared with protein and nucleic acid, the research of polysaccharides is still in the primary stage. The relationship between structure and function of polysaccharides is not clear. In this review, we highlighted the main methods of extraction, purification and structure identification of polysaccharides; summarized their biological activities including immunoregulation, hypoglycemic, anti-tumor, anti-virus, anti-coagulation, and so on. Particularly, the relationship between their structures and activities was described. In addition, the applications of polysaccharides in health food, medicine and cosmetics were also reviewed. This review can help polysaccharide researchers quickly understand the whole process of polysaccharides research, and also provide a reference for the comprehensive utilization of polysaccharides. We need to standardize the research of polysaccharides to make the experimental data more universal, and take it as important references in the review process. Glycomic may appear as the next "omic" after genomic and proteomic in the future. This review provides support for the advancement of glycomics.

Genome sequencing holds the promise for great public health benefits. It is currently being used in the context of rare disease diagnosis and novel gene identification, but also has the potential to identify genetic disease risk factors in healthy individuals. Genome sequencing technologies are currently being used to identify genetic factors that may influence variability in symptom severity and immune response among patients infected by SARS-CoV-2. The GENCOV study aims to look at the relationship between genetic, serological, and biochemical factors and variability of SARS-CoV-2 symptom severity, and to evaluate the utility of returning genome screening results to study participants. Study participants select which results they wish to receive with a decision aid. Medically actionable information for diagnosis, disease risk estimation, disease prevention, and patient management are provided in a comprehensive genome report. Using a combination of bioinformatics software and custom tools, this article describes a pipeline for the analysis and reporting of genetic results to individuals with COVID-19, including HLA genotyping, large-scale continental ancestry estimation, and pharmacogenomic analysis to determine metabolizer status and drug response. In addition, this pipeline includes reporting of medically actionable conditions from comprehensive gene panels for Cardiology, Neurology, Metabolism, Hereditary Cancer, and Hereditary Kidney, and carrier screening for reproductive planning. Incorporated into the genome report are polygenic risk scores for six diseases-coronary artery disease; atrial fibrillation; type-2 diabetes; and breast, prostate, and colon cancer-as well as blood group genotyping analysis for ABO and Rh blood types and genotyping for other antigens of clinical relevance. The genome report summarizes the findings of these analyses in a way that extensively communicates clinically relevant results to patients and their physicians. © 2022 Wiley Periodicals LLC. Basic Protocol 1: HLA genotyping and disease association Basic Protocol 2: Large-scale continental ancestry estimation Basic Protocol 3: Dosage recommendations for pharmacogenomic gene variants associated with drug response Support Protocol: System setup.

This paper proposes two new radiant floor heating structures based on micro heat pipe array (MHPA), namely cement-tile floor and keel-wood floor. The numerical models for these different floor structures are established and verified by experiments. The temperature distribution and heat transfer process of each part are comprehensively obtained, and the structure is optimized. The results show that the cement-tile floor has the better heat transfer performance of the two. When under the same inlet water temperature and flow rate, the keel-wood floor’s surface temperature distribution is about 2 °C lower than that of the cement-tile floor. The inlet water temperature of cement-tile floor is about 10 °C lower than that of keel-wood structure when the floor surface temperature is the same. During a longitudinal heat transfer above MHPA, the floor surface temperature decreases by 0.5 °C for every 10 mm filling layer increase. In order to reduce the non-uniformity of the floor’s surface temperature and improve the thermal comfort of the heated room, the optimal structure for a floor is given, with the maximum surface temperature difference reduced by 3.35 °C. We used research focusing on new radiant floor heating, with advantages including high efficiency heat transfer, low water supply temperature, simple waterway structure, low resistance and leakage risk, to provide theory and data to support the application of an effective radiant floor heating based on MHPA.

Ionizing radiation (IR) is widely used in the diagnosis and treatment of various cancers. However, IR can cause damage to human health by producing reactive oxygen species. Lactococcus lactis is a type of microorganism that is beneficial to human health and has a strong antioxidant capacity. In this study, the protective effect of normal and IR-induced L. lactis IL1403 cell-free extracts (CFE and IR-CFE, respectively) against oxidative damage in vitro and the radioprotective effect of IR-CFE in vivo was evaluated using 60Coγ-induced oxidative damage model in mice. Results showed that IR-CFE exhibited a stronger oxidative damage-protective effect than CFE for L. lactis IL1403 under H2O2 in vitro. Moreover, IR-CFE also showed strong radioprotective effect on hepatocyte cells (AML-12) under radiation condition, and the effect was better than that of CFE. Animal experiment indicated that IR-CFE could reduce the IR-induced damage to the hematopoietic system by increasing the number of white blood cells and red blood cells in peripheral blood of irradiated mice. It was also observed that IR-CFE could markedly alleviate the 60Coγ-induced oxidative stress via increasing the activities of superoxide dismutase and glutathione peroxidase, enhancing the levels of glutathione, and decreasing the contents of malondialdehyde in serum, liver, and spleen. In addition, IR-CFE also could reduce the activities of alanine transaminase and aspartate aminotransferase in serum, thereby reducing radiation damage to the liver. These results suggested that IR-CFE could be considered as potential candidates for natural radioprotective agents. This study provides a theoretical basis for improving the application of lactic acid bacteria.

Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) extracted from wheat bran were modified by snail enzyme and their physicochemical properties (water retention capacity and oil retention capacity), functional properties (cholesterol adsorption capacity, glucose adsorption capacity and antioxidant activity) and structural characterizations were evaluated. The results showed that snail enzyme modification led to the significant increase in oil retention capacity of IDF, glucose adsorption capacity and cholesterol adsorption capacity of IDF and SDF. Enzymatic modification also markedly improved the DPPH radical scavenging capacity and reducing power of IDF and SDF. Meanwhile, scanning electron microscopy (SEM) analysis indicated the microstructures of IDF and SDF powders were significantly changed. Fourier transfer-infrared spectrometry (FT-IR) showed that snail enzyme modification could degrade the part of cellulose and hemicellulose of IDF and SDF. All these improved physicochemical and functional properties of IDF and SDF might depend on their structural changes. It suggested that snail enzyme modification could effectively improve physicochemical and functional properties of IDF and SDF from wheat bran.

Introduction: Rapid advancements of genome sequencing (GS) technologies have enhanced our understanding of the relationship between genes and human disease. In order to incorporate genomic information into the practice of medicine, new processes for the analysis, reporting and communication of GS data are needed. Methods: blood samples were collected from adults with a PCR-confirmed SARS-CoV-2 (COVID-19) diagnosis (target N=1500). GS was performed. Data was filtered and analyzed using custom pipelines and gene panels. We developed unique patient-facing materials, including an online intake survey, group counseling presentation, and consultation letters in addition to a comprehensive GS report. Results: The final report includes results generated from GS data: 1) Monogenic disease risks; 2) Carrier status; 3) Pharmacogenomic variants; 4) Polygenic risk scores for common conditions; 5) HLA genotype; 6) Genetic ancestry; 7) Blood group; and, 8) COVID-19 viral lineage. Participants complete pre-test genetic counseling and confirm preferences for secondary findings before receiving results. Counseling and referrals are initiated for clinically significant findings. Conclusion: We developed a genetic counseling, reporting, and return of results framework that integrates GS information across multiple areas of human health, presenting possibilities for the clinical application of comprehensive GS data in healthy individuals.

Nisin, a natural peptide produced by Lactococcus lactis cultivation in milk whey, is widely used as a preservative in industrial production. However, nisin can be degraded by endogenous enzymes in foods. In this study, we investigated the antibacterial activity of nisin-soybean protein and nisin-egg white protein and compared them with that of free nisin in cantaloupe juice, which was used as a model of endogenous protease environment. Results showed that endogenous proteases in the model resulted in a loss of nisin activity, but combining nisin with protein (soybean or egg white) resulted in greater protection of its antimicrobial activity by inhibiting endogenous proteases. The microbial addition experiment (Staphylococcus aureus and Micrococcus luteus) and preservation experiment in the food model showed that the antibacterial activity of nisin combined with either of the 2 proteins was higher than that of nisin alone in an endogenous protease environment. In summary, soybean protein and egg white protein improved the protease tolerance of nisin, expanding the application scope of nisin in food.

There are numerous factors restricting wide application of lactic acid bacteria (LAB) in dairy industry, causing urgent demands for novel bioprotectants. Protective effects and metabolites of Lactococcus lactis subsp. lactis (L. lactis) from ultraviolet (UV)-induced supernatant were investigated and the protective mechanism was explored. The strain viability of the group treated with the supernatant of continuous UV irradiation (V1) and the group with intermittent UV irradiation (V2) was 8.45 and 14.13 times of the control group, respectively. Further exploration on the protective of L. lactis supernatant, under different dose of UV treatment, showed it was dose-dependent. The condition for the supernatant with best protective effect was vertical distance 50.00 cm, horizontal distance 25.00 cm, intermittent UV irradiation (30 s interval 30 s) for 4.5 min (V2), which was chose for untargeted metabolite analysis. And that in V1 was for comparative study. There were 181 up-regulated metabolites in V1 and 161 up-regulated metabolites in V2, respectively. Most of the up-regulated metabolites were related to secondary metabolite synthesis, environmental microbial metabolism, antibiotic synthesis and amino acid biosynthesis. Notably, production of dithiothreitol (DTT) in V2 was 65.2-fold higher than that in the control group. Trehalose in ABC transporter pathway was also up-regulated in the metabolites induced by UV. Results indicated that L. lactis could adapt to the UV stress by adjusting metabolic pathways and producing special metabolites to protect itself. This research offers the basis for robust strain development and contributes to initial study on potential bioprotectant.

Caffeic acid phenethyl ester (CAPE) is an efficient bioactive polyphenol ester derived from propolis. However, its poor water solubility, bioavailability, and stability significantly limit its application. Based on the assembly properties of some natural small molecules (NSMs), asiatic acid-caffeic acid phenethyl ester nanoparticles (ASA-CAPE NPs) were prepared to overcome the above defects. After proportion optimization, the encapsulation and loading efficiencies of ASA-CAPE NPs reached 47.72 ± 0.17 % and 11.62 ± 0.42 %, respectively. Characterization results showed that ASA-CAPE NPs, mainly assembled by hydrogen bonds and hydrophobic forces, possessed regular spherical morphology with a diameter size of less than 300 nm. Additionally, ASA-CAPE NPs presented improved water solubility, stability, and bioactivities than free CAPE. Besides, ASA-CAPE NPs also exhibited good sustained release of CAPE during the gastrointestinal digestion in vitro. Above all, ASA-CAPE NPs provide a new idea for efficiently utilizing hydrophobic active compounds in the functional food field.

As a common medicinal and edible plant, Zingiber officinale Roscoe (ginger) is often used for the prevention of motion sickness. However, the mechanism of its anti-motion sickness remains to be elucidated.To explore novel treatment for motion sickness with less side effects, anti-motion sickness effect of ginger (Zingiber officinale) extract (GE) and the possible molecular mechanisms were investigated.The anti-motion sickness effect of ginger was evaluated through mice animal experimental models. Components of ginger that might contribute to the anti-motion sickness effect were analyzed by LC-MS/MS. Subsequently, biochemical analysis integrated with serum metabolomic profiling were performed to reveal the systematic response of motion sickness mice to ginger extract's amelioration effect.Exhaustive swimming time of mice in the GE group reached 8.9 min, which was 52.2% longer than that in the model group. Motion sickness index scores and time taken traversing balance beam of mice in the GE group were decreased by 53.2% and 38.5%, respectively. LC-MS/MS analysis suggested that various active ingredients in GE, such as gingerol, ginger oil and terpenoids, might contribute to its appealing anti-motion sickness activity. Biochemical analysis revealed that GE can relieve motion sickness through reducing histamine and acetylcholine release in vestibular system, regulating fatty acid oxidation, sugar metabolism and bile acid metabolism in mice.Gavage of mice with GE can effectively relieve the symptoms of autonomic nervous system dysfunction, improve the balance and coordination ability and ameliorate the ability to complete complex work after rotation stimulation. GE has attractive potential for development and utilization as novel anti-motion sickness food or drugs.

Hypoxia inducible factor (HIF) is a hypoxia-associated transcription factor that has a protective role against hypoxia-induced damage. Prolyl hydroxylase-2 (PHD2) is a dioxygenase enzyme that specifically hydroxylates HIF targeting it for degradation, therefore, inhibition of the PHD2 enzyme activity acts to upregulate HIF function. This study was to identify novel PHD2 inhibitors.An established fluorescence-based PHD2 activity assay was used for inhibitors screening. Western blot and quantitative real-time PCR was used to detect the protein and mRNA levels respectively. Further animal experiment was carried out.Caffeic acid was screened and identified as a novel PHD2 inhibitor. Caffeic acid treated PC12 and SH-SY5Y neuronal cell lines stabilized endogenous HIF-1α protein levels and consequently increased mRNA levels of its downstream regulated genes VEGF and EPO. Caffeic acid treatment reduced hypoxia-induced cell apoptosis and promoted HIF/BNIP3-mediated mitophagy. Moreover, animal studies indicated that caffeic acid increased the level of HIF-1α protein and mRNA levels of VEGF and EPO in the brain of mice exposed to hypoxia. Conventional brain injury markers including malondialdehyde, lactic acid and lactate dehydrogenase in the caffeic acid treated mice were shown to be reduced to the levels of the control group.This study suggests that caffeic acid inhibits PHD2 enzyme activity which then activates the hypoxia-associated transcription factor HIF leading to a neuroprotective effect against hypoxia.

Implementation of polygenic risk scores (PRS) may improve disease prevention and management but requires the construction and validation of clinical assays, interpretation, and reporting pipelines. We developed a clinical genotype array-based assay for published PRS for 6 common diseases. First, we calculated PRS for 36,423 Mass General Brigham Biobank (MGBB) participants. Finding significant variation in the PRS distributions by race, we implemented adjustment for population structure with ancestry-informative principal components. We replicated published thresholds for odds ratio (OR)>2 in MGBB overall [ranging from 1.75 (1.57, 1.95) for Type 2 diabetes to 2.38 (2.07, 2.73) for breast cancer]. After confirming the high performance and robustness of the pipeline for use as a clinical assay, we analyzed the first 141 prospective samples from the Genomic Medicine at VA Study; frequency of PRS corresponding to published OR>2 ranged from 5/141 (3.6%) for colorectal cancer to 8/48 (16.7%) for breast cancer. Our development of a clinical PRS assay for multiple conditions illustrates the generalizability of this process and necessary technical and reporting decisions for meaningful clinical PRS implementation.

Implementation of polygenic risk scores (PRS) may improve disease prevention and management but poses several challenges: the construction of clinically valid assays, interpretation for individual patients, and the development of clinical workflows and resources to support their use in patient care. For the ongoing Veterans Affairs Genomic Medicine at Veterans Affairs (GenoVA) Study we developed a clinical genotype array-based assay for six published PRS. We used data from 36,423 Mass General Brigham Biobank participants and adjustment for population structure to replicate known PRS-disease associations and published PRS thresholds for a disease odds ratio (OR) of 2 (ranging from 1.75 (95% CI: 1.57-1.95) for type 2 diabetes to 2.38 (95% CI: 2.07-2.73) for breast cancer). After confirming the high performance and robustness of the pipeline for use as a clinical assay for individual patients, we analyzed the first 227 prospective samples from the GenoVA Study and found that the frequency of PRS corresponding to published OR 2 ranged from 13/227 (5.7%) for colorectal cancer to 23/150 (15.3%) for prostate cancer. In addition to the PRS laboratory report, we developed physician- and patient-oriented informational materials to support decision-making about PRS results. Our work illustrates the generalizable development of a clinical PRS assay for multiple conditions and the technical, reporting and clinical workflow challenges for implementing PRS information in the clinic.

Native potato starch (NPS) with tea polyphenols (TPs) was treated in a planetary ball mill, and the effects of co-grinding on properties and digestibility of starch were studied. The X-ray diffraction (XRD) results showed that the crystal structure of starch granules was destroyed after 7 h of ball grinding, and their crystallinity degree reduced from 38.1% to 8.3%. The scanning electron microscopy (SEM) analyses indicated that the damaged starch granules and TPs displayed agglomerates after 7 h of milling. The Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) results demonstrated the existence of an interaction between starch chains and TPs, which improved the thermal stability and gelatinization temperatures of starch. The ball-milled starches with different amount of TPs showed significant variability to in vitro digestion (the contents of slowly digestible starch and resistant starch). Therefore, the produced ball-milled mixtures may be a desired dietary product for postprandial glycemic control.

To enhance the stability of lipases, the additive method is attractive because of its high efficiency and simplicity, of which β-cyclodextrin (β-CD), as an additive has attracted attention. In the present study, the effects of β-CD on enzymatic hydrolysis of hemp seed oil by lipases were investigated. The stability, spectroscopy, and reusability of Candida sp.99–125 were compared by the addition of β-CD, respectively. The results showed that Candida sp.99–125 could produce the highest yield of α-linolenic acid (ALA, 18.27%, w/w) in the presence of β-CD after 24h, and the thermal stability of lipase was also improved. The UV spectroscopy showed that the absorbance of lipase decreased with increasing concentrations of β-CD and the fluorescence result was similar. Moreover, the reusability of lipase with β-CD was better than free lipase. This study revealed that β-CD could increase hydrolysis activity and stability of the lipase, thereby improving the hydrolytic process of hemp seed oil by Candida sp.99–125.

Natural products can be used as natural radiosensitizers and radioprotectors, showing promising effects in cancer treatments in combination with radiotherapy, while reducing ionizing radiation (IR) damage to normal cells/tissues. The different effects of natural products on irradiated normal and tumor cells/tissues have attracted more and more researchers’ interest. Nonetheless, the clinical applications of natural products in radiotherapy are few, which may be related to their low bioavailability in the human body. Here, we displayed the radiation protection and radiation sensitization of major natural products, highlighted the related molecular mechanisms of these bioactive substances combined with radiotherapy to treat cancer, and critically reviewed their deficiency and improved measures. Lastly, several clinical trials were presented to verify the clinical application of natural products as radiosensitizers and radioprotectors. Further clinical evaluation is still needed. This review provides a reference for the utilization of natural products as radiosensitizers and radioprotectors.

Prolyl hydroxylase-2 (PHD2) is a dioxygenase enzyme that specifically hydroxylates the hypoxia inducible factor (HIF) which then targets it for degradation in oxygenated cells. Inhibition of the activity of the PHD2 enzyme under hypoxic environmental conditions acts to upregulate HIF. Thus, PHD2 inhibitors may serve as a promising treatment for HIF-dependent diseases. In this study, recombinant PHD2 protein was successfully expressed using a baculovirus-insect cell expression secretory system. PHD2 was purified and in combination with bacterially expressed functional von Hippel Lindau protein-elongin B-elongin C (VBC) protein complex was used to successfully develop a fluorescence-based PHD2 activity assay. Myricetin was identified as a novel potent PHD2 inhibitor by high-throughput screening of a natural compound library. Further studies showed that treatment of human neuroblastoma SH-SY5Y cells with Myricetin increased HIF-1α protein levels. These results indicate that the insect cell expression system is capable of producing highly active recombinant PHD2 protein from which a fluorescence-based activity assay can be developed for high-throughput screening applications.

Burns are a global public health problem and the treatment of burn wounds is a major medical and economic issue. White jade snails (Achatina fulica) are now widely distributed in Asia, and they have been used to treat burns in folk medicine of China. In this study, the glycoproteins from white jade snails were investigated and their effect on burn healing was evaluated by a mouse burn model. The results showed that the snail mucus was mainly composed of proteins and polysaccharides, and it had good adhesion. The main component of snail mucus was glycoprotein from the results of DEAE Sepharose FF ion exchange chromatography. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging effect of 1 mg/mL snail mucus reached 13.77%. The wound healing rate of the snail mucus group was higher than that of the control group (p 0.0001). Histopathological results showed that mice in the snail mucus group had a faster healing than that of the control group. The biochemical analysis was in agreement with the histopathological findings. These results suggested that glycoproteins from snail mucus showed effective wound healing activities in the skin of experimentally burned mice.

L. lactis is known as industrial starter in the fermentation of dairy and meat products, and it plays an important role in human health as an edible probiotic. During industrial production, L. lactis often experiences different stresses that delay the growth and decrease the survival in some serious conditions. In this study, the protective effects of hydroxypropyl β-cyclodextrin (HP β-CD) on L. lactis under multiple stresses were investigated. The microbial cells were treated with different stresses including heat, NaCl, cold, and H2 O2 stresses, and the results were showed by measuring the OD600 or spot plating method. The growth and tolerance were improved when HP β-CD was added during different stress conditions, better than that of trehalose. Besides, the scanning electron microscopic and fluorescence spectrum studies showed that HP β-CD could combine with L. lactis to protect the cell structure, suggesting that HP β-CD may act as a protective agent of L. lactis. Therefore, HP β-CD could be considered as a potential protective agent to be applied in food industry, and its protective mechanism on L. lactis still needs further investigation.

A kind of novel polysaccharides from Chinese yam (Dioscorea opposita Thunb.) was prepared by fermentation with a fungal probiotic Saccharomyces boulardii. The preparation methods and parameters of fermented Chinese yam polysaccharides (FCYP) were optimized. Molecular weight and FT-IR spectrum of the optimized FCYP were also evaluated, along with its biological activities and digestion behaviors. Results showed that FCYP distributed in fermentation supernatant possessed the best total reducing power. On this basis, the highly active FCYP was obtained under the optimal fermentation conditions: fermentation time of 36 h, inoculation volume of 6% and solid-liquid ratio of 1:25 g/mL. Compared with unfermented Chinese yam polysaccharides (UCYP), the molecular weight of FCYP decreased prominently, accompanied with a significant increase of in vitro antioxidant activity. Meanwhile, FCYP also exhibited a favorable radioprotective effect at the cellular level. After in vitro simulated gastrointestinal digestion, FCYP remained relatively well bioactive stability, with lower molecular weight and the occurrence of lamellar morphological structure. Overall, Chinese yam polysaccharides fermented by S. boulardii were obtained with easier digestion and better functionality properties including antioxidant activity and radioprotection effect, which could be considered as one of health food components.

Based on the analysis of the influence of the surface quality of metal materials on the use of machinery, this paper discusses the influence of raw material quality, technical level, residual stress, cold work hardening, machine tool machining error, cutting tool machining error, mechanical positioning error and mechanical adjustment error on the surface quality and machining accuracy of metal materials. By studying the measures such as strengthening the quality control of raw materials, reasonably selecting processing technology, controlling the processing process, reducing the original error and making error compensation, the aim is to optimize the machining environment and improve the processing quality of finished products.

Dictyopteris divaricata is a kind of important brown algae with many biological activities. It has been receiving more and more attention, yet there are rarely studies done on its polysaccharides. In this study, the optimum extraction and biological activity of seaweed polysaccharides from Dictyopteris divaricata (DDSP) were investigated. Response surface methodology (RSM), based on a three-level, three-variable Box-Behnken design (BBD), was employed to obtain the best possible combinations for maximum polysaccharides yield. The optimum extraction conditions were as follows: liquid-solid ratio of 110 mL/g, extraction time of 6 h and extraction temperature of 100 °C. Under these conditions, the experimental yield was 3.05%, which was in close agreement with the predicted value of 3.15%. The average molecular weight of DDSP was 58.05 kDa. Gas chromatograph (GC) results showed that DDSP was composed of fucose, xylose, mannose, glucose and galactose with the corresponding molar ratio of 4.45:2.74:1.00:2.94:1.35. Biological activity showed that DDSP exhibited strong antioxidant activity in vitro and possessed the potential on stimulating immune response of RAW264.7 cells. So DDSP can be used as a natural ingredient in functional foods.