Comprehensive review of milk fat globule membrane proteins across mammals and lactation periods in health and disease.

Milk fat globule membrane (MFGM) is a three-layer membrane-like structure encasing natural milk fat globules (MFGs). MFGM holds promise as a nutritional supplement because of the numerous physiological functions of its constituent protein. This review summarizes and compares the differences in MFGM protein composition across various species, including bovines, goats, camels, mares, and donkeys, and different lactation periods, such as colostrum and mature milk, as assessed by techniques such as proteomics and mass spectrometry. We also discuss the health benefits of MFGM proteins throughout life. MFGM proteins promote intestinal development, neurodevelopment, and glucose and lipid metabolism by upregulating tight junction protein expression, brain function-related genes, and glucose and fatty acid biosynthesis processes. We focus on the mechanisms underlying these beneficial effects of MFGM proteins. MFGM proteins activate key substances in in signaling pathways, such as the phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, and myosin light chain kinase signaling pathways. Overall, the consumption of MFGM proteins plays an essential role in conferring health benefits, some of which are important throughout the mammalian life cycle.

Types and amounts of MFGM proteins in mammals, as assessed by proteomic and mass spectrometry analysis, are summarized.Colostrum MFGM contains more acute phase proteins, whereas mature milk has higher levels of mucins (1 and 15), ADPH, XDH, and FABP.Health benefits of MFGM proteins, including intestinal development, neurodevelopment, and immune activity enhancement, are summarized.MFGM proteins have been shown to significantly activate the PI3K/Akt/mTOR signaling pathway, promoting cell proliferation and glycolipid metabolism.

Production of polyunsaturated fatty acids in pork backfat fermented by Mucor circinelloides.

Pork backfat (PB) contains excessive saturated fatty acids (SFAs), but lacks polyunsaturated fatty acids (PUFAs). Excessive SFAs can be used as a substrate for the growth of certain microorganisms that convert them into PUFAs and monounsaturated fatty acids (MUFAs), and the added value of PB can be enhanced. In this study, Mucor circinelloides CBS 277.49 and Lactiplantacillus plantarum CGMCC 24189 were co-cultured for conversion of PB into fermented pork backfat (FPB) with high level of PUFAs. Our results showed that the content of γ-linolenic acid (GLA) and linoleic acid (LA) in the surface of FPB reached 9.04 ± 0.14 mg/g and 107.31 ± 5.16 mg/g for 7-day fermentation, respectively. To convert the internal SFAs of PB, ultrasound combined with papain was used to promote the penetrative growth of M. circinelloides into the internal PB, and the GLA level in the third layer of fat reached 2.58 ± 0.31 mg/g FPB. The internal growth of M. circinelloides in PB was promoted by adjusting the oxygen rate and ventilation rate through the wind velocity sensor. When the oxygen rate is 2 m/s and the ventilation rate is 18 m3/h, the GLA level in the third layer of fat reached 4.13 ± 1.01 mg/g FPB. To further improve the level of PUFAs in PB, FPB was produced by M. circinelloides at 18 °C. The GLA content on the surface of FPB reached 15.73 ± 1.13 mg/g FPB, and the GLA yield in the second and third layers of fat reached 8.68 ± 1.77 mg/g FPB and 6.13 ± 1.28 mg/g FPB, the LA yield in the second and third layers of fat reached 105.45 ± 5.01 mg/g FPB and 98.46 ± 4.14 mg/g FPB, respectively. These results suggested that excessive SFAs in PB can be converted into PUFAs and provided a new technique for improving PUFAs in FPB. KEY POINTS: • This article achieved the conversion of PUFAs in pork backfat by Mucor circinelloides CBS 277.49 and Lactiplantacillus plantarum CGMCC 24189. • This article solved the internal growth of M. circinelloides CBS277.49 in pork backfat by ultrasound combined with papain. • This article proposed an innovative of promoting the internal growth of M. circinelloides and increasing the PUFAs production by oxygen ventilation in pork backfat.

The Role of SHP2 in Advancing COPD: Insights into Oxidative Stress, Endoplasmic Reticulum Stress, and Pyroptosis.

Background: Chronic Obstructive Pulmonary Disease (COPD) is characterized by airflow limitation and inflammation resulting from genetic and environmental factors, notably cigarette smoke. Pyroptosis, a cell death process, is implicated in COPD, but its mechanisms are unclear. SHP2, a phosphatase, modulates inflammatory pathways, suggesting a role in COPD pathogenesis and potential therapeutic avenues. Objective: This study investigates the mechanism by which SHP2 regulates cell pyroptosis in bronchial epithelial cells in COPD patients. Methods: In this prospective study, we employed in vivo and in vitro models to investigate the mechanisms underlying COPD progression. Hematoxylin and eosin (H&E) staining were utilized to assess the morphological changes characteristic of COPD. Electron microscopy enabled precise quantification of pyroptotic bodies to highlight cellular changes associated with COPD pathogenesis. Immunofluorescence analysis facilitated the measurement of protein fluorescence intensity, allowing for the assessment of inflammatory responses within bronchial epithelial cells. Additionally, Western blot analysis was conducted to evaluate the expression levels of key pathway proteins involved in COPD progression. Results: In the COPD model, lesions worsened in SHP2-KD mice compared to SHP2-NC. Western blot results showed increased p22, p47, p-IRE1α, XBP1, STING, p-TBK1, NLRP3, Caspase1, and IL-1ß expression levels in both in vivo and in vitro models. Transmission electron microscopy revealed more pyroptotic bodies in SHP2-KD+CSE than in SHP2-NC+CSE. Immunofluorescence demonstrated significantly higher NLRP3 and GSDMD fluorescence intensities in SHP2-KD+CSE versus SHP2-NC+CSE. Additionally, Western blot analysis indicated increased expression of Bax, Caspase3, Caspase8, and Caspase9 proteins in the in vitro model. No differences were observed between SHP2 NC and SHP2-KD groups without CSE stimulation in immunofluorescence, electron microscopy, and Western blot findings in the cellular model. Conclusions: SHP2 promotes COPD progression by inducing oxidative stress, endoplasmic reticulum stress, and pyroptosis.

Catalytic mechanisms underlying fungal fatty acid desaturases activities.

Polyunsaturated fatty acids (PUFAs) have beneficial roles in a variety of human pathologies and disorders. Owing to the limited source of PUFAs in animals and plants, microorganisms, especially fungi, have become a new source of PUFAs. In fungi, fatty acid desaturases (F-FADS) are the main enzymes that convert saturated fatty acids (SFAs) into PUFAs. Their catalytic activities and substrate specificities, which are directly dependent on the structure of the FADS proteins, determine their efficiency to convert SFAs to PUFAs. Catalytic mechanisms underlying F-FADS activities can be determined from the findings of the relationship between their structure and function. In this review, the advances made in the past decade in terms of catalytic activities and substrate specificities of the fungal FADS cluster are summarized. The relationship between the key domain(s) and site(s) in F-FADS proteins and their catalytic activity is highlighted, and the FADS cluster is analyzed phylogenetically. In addition, subcellular localization of F-FADS is discussed. Finally, we provide prospective crystal structures of F-FADSs. The findings may provide a reference for the resolution of the crystal structures of F-FADS proteins and facilitate the increase in fungal PUFA production for human health.

Recent developments in horizontal gene transfer with the adaptive innovation of fermented foods.

Horizontal gene transfer (HGT) has contributed significantly to the adaptability of bacteria, yeast and mold in fermented foods, whose evidence has been found in several fermented foods. Although not every HGT has biological significance, it plays an important role in improving the quality of fermented foods. In this review, how HGT facilitated microbial domestication and adaptive evolution in fermented foods was discussed. HGT can assist in the industrial innovation of fermented foods, and this adaptive evolution strategy can improve the quality of fermented foods. Additionally, the mechanism underlying HGT in fermented foods were analyzed. Furthermore, the critical bottlenecks involved in optimizing HGT during the production of fermented foods and strategies for optimizing HGT were proposed. Finally, the prospect of HGT for promoting the industrial innovation of fermented foods was highlighted. The comprehensive report on HGT in fermented foods provides a new trend for domesticating preferable starters for food fermentation, thus optimizing the quality and improving the industrial production of fermented foods.

Structural characterization and hepatoprotective activity of exopolysaccharide from Bacillus velezensis SN-1.

BACKGROUND: Exopolysaccharide biopolymers produced by microorganisms are crucial to the environment. They contribute to areas such as the health and bionanotechnology sectors, food and cosmetic industries as gelling agents, and environmental sector as flocculants owing to their biodegradability and non-toxic nature. The current study aimed to isolate the fraction of released exopolysaccharide (rEPS) by Bacillus velezensis SN-1 from Chinese Da-Jiang. RESULTS: The weighted average molecular weight of the major isolated component, rEPS-2, was 202 kDa, and its monosaccharide composition included mannose, glucose, and galactose at a molar ratio of 0.38:0.30:0.32. Further, the rEPS-2 was characterized using methylation analysis and one-dimensional/two-dimensional nuclear magnetic resonance (1D/2D NMR) spectroscopy. In vivo hepatoprotective effects indicated that rEPS-2 could alleviate carbon tetrachloride (CCl4 )-induced liver injury in mice by lowering the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and the malondialdehyde (MDA) levels. Furthermore, rEPS-2 can increase the expression of antioxidant genes HO-1, GCLC and NQO1 in the Nrf2/ARE signaling pathway, thereby increasing the activity of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and reduced catalase (CAT) in liver cells. Furthermore, the rEPS-2 can be used and modulate the gut microbiota of mice with liver injury caused by CCl4 . CONCLUSIONS: These results suggest that rEPS-2 has promising potential to serve as hepatoprotective agents. © 2022 Society of Chemical Industry.

Linoleic acid enrichment of cheese by okara flour and Geotrichum candidum overexpressing Δ12 fatty acid desaturase.

BACKGROUND: Mold-ripened cheeses have low levels of unsaturated fatty acids (UFAs). Geotrichum candidum is an adjunct culture for the development of Geotrichum-ripened cheese but has a low ability to produce high levels of UFAs. Δ12 fatty acid desaturase (FADS12) is a pivotal enzyme that converts oleic acid (OA) to linoleic acid (LA) and plays a vital role in UFA biosynthesis. By investigating FADS12 catalytic activity from various species with OA substrates, we found that FADS12 from Mucor circinelloides (McFADS12) had the highest catalytic activity for OA. RESULTS: In the current study, a plasmid harboring McFADS12 was constructed and overexpressed in G. candidum. Our results showed that LA production increased to 31.1 ± 1.4% in engineered G. candidum - three times higher than that in wild-type G. candidum. To enhance LA production, an exogenous substrate (OA) was supplemented, and the yield of LA was increased to 154 ± 6 mg L-1 in engineered G. candidum. Engineered G. candidum was used as an adjunct culture for Geotrichum-ripened cheese production. The LA level reached 74.3 ± 5.4 g kg-1 cheese, whereas the level of saturated fatty acids (SFAs) decreased by 9.9 ± 0.5%. In addition, the soybean byproduct (okara) was introduced into the engineered G. candidum growth and the level of LA increased to 126 ± 4 g kg-1 cheese and the percentage of UFAs:SFAs increased from 0.8:1 to 1.3:1. CONCLUSION: This study offers a suitable technology for converting SFAs to UFAs in Geotrichum-ripened cheeses and provides a novel trend for converting soybean waste into a value-added product. © 2022 Society of Chemical Industry.

A systematic review on the flavor of soy-based fermented foods: Core fermentation microbiome, multisensory flavor substances, key enzymes, and metabolic pathways.

The characteristic flavor of fermented foods has an important impact on the purchasing decisions of consumers, and its production mechanisms are a concern for scientists worldwide. The perception of food flavor is a complex process involving olfaction, taste, vision, and oral touch, with various senses contributing to specific properties of the flavor. Soy-based fermented products are popular because of their unique flavors, especially in Asian countries, where they occupy an important place in the dietary structure. Microorganisms, known as the souls of fermented foods, can influence the sensory properties of soy-based fermented foods through various metabolic pathways, and are closely related to the formation of multisensory properties. Therefore, this review systematically summarizes the core microbiome and its interactions that play an active role in representative soy-based fermented foods, such as fermented soymilk, soy sauce, soybean paste, sufu, and douchi. The mechanism of action of the core microbial community on multisensory flavor quality is revealed here. Revealing the fermentation core microbiome and related enzymes provides important guidance for the development of flavor-enhancement strategies and related genetically engineered bacteria.

Leaf transcriptome analysis of Medicago ruthenica revealed its response and adaptive strategy to drought and drought recovery.

BACKGROUND: Drought is one of the main causes of losses in forage crop yield and animal production. Medicago ruthenica (L.) cv. Zhilixing is a high-yielding alfalfa cultivar also known for its high tolerance to drought. We analyzed the transcriptome profile of this cultivar throughout drought stress and recovery and we were able to describe its phased response through the expression profiles of overlapping gene networks and drought-specific genes. RESULTS: The ABA and auxin signal transduction pathways are overlapping pathways in response to drought and drought recovery in forage crops. Medicago ruthenica (L.) cv. Zhilixing adopts different strategies at different degrees of drought stress. On the 9th day of drought, transcriptional regulations related to osmoregulation are enhanced mainly through increased activities of carbohydrate and amino acid metabolism, while photosynthetic activities were reduced to slow down growth. With drought prolonging, on the 12th day of drought, the synthesis of proline and other stored organic substances was suppressed in general. After recovery, Medicago ruthenica synthesizes flavonoids through the flavonoid biosynthesis pathway to remove accumulated ROS and repair the oxidative damage from water stress. In addition, the regulation of circadian rhythm seems to accelerate the drought recovery process. CONCLUSIONS: Medicago ruthenica adapts to drought by regulating the osmoregulatory system and photosynthesis, which appears to involve the ABA and auxin signaling pathways as key regulators. Furthermore, the synthesis of flavonoids and the regulation of the circadian rhythm can accelerate the recovery process. These results enriched our knowledge of molecular responses to drought and drought recovery in Medicago ruthenica and provide useful information for the development of new legume forage grass varieties with improved adaptability to drought stress.

Transcriptome profiling of flower buds of male-sterile lines provides new insights into male sterility mechanism in alfalfa.

BACKGROUND: The use of heterosis to produce hybrid seeds is a challenge to breeding for improved crop yield. In previous studies, we isolated a male sterile alfalfa hybrid and successfully obtained a genetically stable alfalfa male sterile line through backcrossing, henceforth named MS-4. In this study, we used RNA-seq technology to analyze the transcriptome profiles of the male sterile line (MS-4) and the male fertile line (MF) of alfalfa to elucidate the mechanism of male sterility. RESULTS: We screened a total of 11,812 differentially expressed genes (DEGs) from both MS-4 and MF lines at three different stages of anther development. Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that these DEGs are mainly involved in processes such as energy metabolism, lipid and amino acid metabolism, carbohydrate metabolism, in addition to cell synthesis and aging. The results from protein-protein interaction (PPI) network analysis showed that the ribosomal protein (MS.Gene25178) was the core gene in the network. We also found that transcriptional regulation was an influential factor in the development of anthers. CONCLUSIONS: Our findings provide new insights into understanding of the fertility changes in the male sterile (MS-4) of alfalfa.

A multi center real world observation to evaluate the efficacy of cryotherapy versus local hyperthermia for the treatment of plane warts.

Most plane warts are recalcitrant to treatment. Both cryotherapy and local hyperthermia have been applied to treat plane warts. However, no direct comparative study on their respective efficacy and safety has ever been performed. To assess the efficacy and safety of local hyperthermia at 43 ± 1°C versus liquid nitrogen cryotherapy for plane warts. Sequential patients with plane warts entered the study, either receiving cryotherapy or local hyperthermia therapy at the discretion of the patients and the recommendations of consultants. Cryotherapy with liquid nitrogen was delivered in two sessions 2 weeks apart, while local hyperthermia was delivered on three consecutive days, plus two similar treatments 10 ± 3 days later. The temperature over the treated skin surface was set at 43 ± 1°C for 30 min in each session. The primary outcome was the clearance rates of the lesions 6 months after treatment. Among the 194 participants enrolled, 183 were included in the analysis at 6 months. Local hyperthermia and cryotherapy achieved clearance rates of 35.56% (48/135) and 31.25% (15/48), respectively (p = 0.724); recurrence rates of 16.67% (8/48) and 53.33% (8/15) (p = 0.01); and adverse events rates of 20.74% (28/135) and 83.33% (40/48), respectively (p < 0.001). Cryotherapy had a higher pain score (p < 0.001) and a longer healing time (p < 0.001). Local hyperthermia at 43°C and cryotherapy had similar efficacy for plane warts. Local hyperthermia had a safer profile than cryotherapy but it required more treatment visits during a treatment course. More patients preferred local hyperthermia due to its treatment friendly nature.

Local Hyperthermia Versus Cryotherapy for Treatment of Plantar Warts: A Prospective Multi-centre Non-randomized Concurrent Controlled Clinical Trial.

Cryotherapy is one of the most common treatments for warts; however, pain during treatment and relatively high recurrence rates limit its use. Local hyperthermia has also been used successfully in the treatment of plantar warts. The aim of this study was to compare the clinical effectiveness of local hyperthermia vs cryotherapy for the treatment of plantar warts. This multi- centre, open, 2-arm, non-randomized concurrent controlled trial included 1,027 patients, who received either cryotherapy or local hyperthermia treatment. Three months after treatment, local hyperthermia and cryotherapy achieved complete clearance rates of 50.9% and 54.3%, respectively. Recurrence rates were 0.8% and 12%, respectively. Pain scores during local hyperthermia were significantly lower than for cryotherapy. Both local hyperthermia and cryotherapy demonstrated similar efficacy for clearance of plantar warts; while local hyperthermia had a lower recurrence rate and lower pain sensation during treatment.

Isolation of a New Polysaccharide from Dandelion Leaves and Evaluation of Its Antioxidant, Antibacterial, and Anticancer Activities.

Dandelion, in China, has a long history as a medicinal and edible plant, and possesses high nutritional and medical value. The present study aimed to isolate a new polysaccharide (DLP-3) from dandelion leaves and to evaluate its antioxidant, antibacterial, and anticancer activities. The structure of DLP-3 was analyzed using HPLC, FT-IR, SEM, GC-MS, and NMR spectroscopy. DLP-3 mainly consisted of Man, Rha, GlcA, Glc, Gal, and Ara with molar ratios of 2.32, 0.87, 1.21, 3.84, 1.00, and 1.05, respectively, with a molecular weight of 43.2 kDa. The main linkages of DLP-3 contained (1→4)-α-d-Glc, (1→4,6)-α-d-Glc, (1→6)-α-d-Gal, (1→2)-α-d-Man, (1→4)-α-d-Man, ß-l-Ara-(1→, and α-l-Rha-(1→. DLP-3 exhibited a smooth surface, purely flake-like structure, and a triple helix conformation. Moreover, DLP-3 presented obvious antioxidant and antibacterial activities in a concentration-dependent manner. DLP-3 showed significant anticancer activities by inhibiting tumor cell proliferation. These findings provide a theoretical basis for the application of DLP-3 as a natural functional active substance in functional foods.

Comparative proteomic analysis of three Lactobacillus plantarum strains under salt stress by iTRAQ.

BACKGROUND: Lactobacillus plantarum, a common species of lactic acid bacteria, is used to improve the flavor of traditional fermented food. Under salt stress, different strains of L. plantarum can respond differently. In this work, proteomics and bioinformatics analysis of L. plantarum strains (ATCC14917, FS5-5, and 208) grown under salt stress (240 g L-1 sodium chloride (NaCl)) were investigated based on the isobaric tags for relative and absolute quantitation method. RESULTS: Although 171 differentially expressed proteins (DEPs) were observed, only 44, 57, and 112 DEPs were identified in the strains ATCC14917, FS5-5, and 208 respectively. There were 33, 191, and 179 specific DEPs in ATCC14917 versus FS5-5, in 208 versus FS5-5, and in strain 208 versus ATCC14917 in 240 g L-1 NaCl. These DEPs indicate that the three strains, from pickles, fermented soybean paste, and fermented milk, may have different salt stress responses. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes analysis showed that most DEPs observed were involved in protein biosynthesis, nucleotide metabolism, and sugar metabolism. Twenty-six significantly different DEPs that were possibly associated with salt response were selected and further analyzed for gene expression level and pattern by quantitative reverse transcription polymerase chain reaction. Pyruvate kinase and cysteine desulfurase had similar expression patterns in all three strains; glutamate decarboxylase expression was upregulated in FS5-5 and significantly upregulated in strain 208; RNA polymerase subunit alpha was downregulated in FS5-5 but upregulated in strain 208. CONCLUSIONS: These results also showed that the salt stress response of strain 208 may involve higher numbers of genes than the other strains. This research provides a theoretical basis for improvement of salt tolerance of L. plantarum in industrial production. © 2020 Society of Chemical Industry.

Structural characterization and antioxidant potential of a novel exopolysaccharide produced by Bacillus velezensis SN-1 from spontaneously fermented Da-Jiang.

The aim of this study was to characterize the exopolysaccharide (EPS) produced by Bacillus velezensis SN-1 (B. velezensis SN-1) (EPS-SN-1), which was isolated from the fermented Da jiang. The microbe made crude exopolysaccharides EPS-SN-1 was produced throughout the bacterial growth period, and the highest yield (2.7 g/L) was obtained with sucrose as the carbon source. As per high performance liquid chromatography (HPLC), EPS-SN-1 is a heteropolysaccharide consisting of glucose, mannose and fructose, with a high molecular weight of 2.21 × 105 Da. FTIR spectra further indicated the presence of hydroxyl and carbonyl groups, and NMR analysis confirmed both α- and ß-glycosidic bonds. Furthermore, differential scanning calorimetry (DSC) showed that EPS-SN-1 has high thermal stability with fusion point of 270.7 °C. Finally, EPS-SN-1 demonstrated strong antioxidant capacity via its ability to scavenge hydroxyl radical (•OH), 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical, ABTS radical (ABTS•+) and oxygen radical (O2-•). Taken together, EPS-SN-1 is a promising natural antioxidant and probiotic with potential applications in the food industry.

Rapid and simple detection of Bacillus cereus in milk by real-time competitive annealing mediated isothermal amplification.

Bacillus cereus (B. cereus) is widespread in nature and considered an important foodborne pathogen, which can lead to emetic syndrome and diarrheal illness. Therefore, appropriate detection methods are needed to effectively monitor this pathogenic bacterium. Competitive annealing mediated isothermal amplification (CAMP) is a novel nucleic-acid-based detection technology that amplifies DNA with high sensitivity and specificity under isothermal conditions. The aim of this study was to develop a real-time CAMP assay for the rapid and simple detection of B. cereus in milk. In this system, a pair of primers was designed to specifically target the entFM gene of B. cereus. Compared with the conventional PCR method, the CAMP assay has higher sensitivity, the same specificity and shorter detection time. The detection limits of the CAMP assay for pure bacterial cultures and artificially contaminated milk samples were all 59 CFU mL-1. And this detection method showed a wide linear range (from 5.9 × 105 to 59 CFU mL-1) and satisfactory recovery values (from 75.76% to 106.78%). These results indicate that the developed CAMP assay is a potentially useful method for the detection of B. cereus in milk.

Effects of skim milk fermented with Lactobacillus plantarum WW on the constitutions of rats fed a high-fat diet.

This study investigated the effects of Lactobacillus plantarum WW-fermented skim milk (FSM) on the physiques of rats fed a high-fat diet and the mechanism of lipid lowering. Sprague-Dawley rats were randomly divided into a normal diet group (A), a high-fat diet group (B), a skim milk diet group (C), and an L. plantarum WW FSM diet group (D). After 12-wk feeding, we found that treatment with L. plantarum WW FSM could significantly alleviate symptoms in the pathological group. Meanwhile, high-throughput sequencing analysis showed that L. plantarum WW FSM also had a certain regulatory effect on the intestinal microorganisms in rats, which can increase the number of lactic acid bacteria and Bacteroides in the intestine. More importantly, real-time quantitative PCR and Western blot analysis showed that the probiotic was also involved in the expression of genes related to fat metabolism, especially the PPARB and CEBPB genes. Our study supports the hypothesis that the WW strain of L. plantarum could be a potential probiotic to be used in functional foods to alter lipid metabolism and reduce cholesterol levels.

Effects of different probiotic combinations on the components and bioactivity of Spirulina.

Spirulina acts as a good dietary nutritional supplement. However, few research studies have been conducted on its fermentation. Three groups of probiotic combinations, lactic acid bacteria, Bacillus strains, and their mixture, were used to investigate Spirulina fermentation. The results showed that lactic acid bacteria significantly increased the content of amino acids and the ratio of essential amino acids to total amino acids in the fermented Spirulina, compared with the unfermented Spirulina, and this trend was enhanced by the strains' mixture. However, compared to unfermented Spirulina, the amino acid levels were significantly decreased after fermentation with Bacillus strains and so was the total free amino acid and essential amino acid content. Fermentation significantly reduced the contents of the offensive components of Spirulina, with significant differences among the three mixed bacterial treatments. Moreover, Bacillus strain fermentation increased the contents of flavonoids and polyphenols compared to the unfermented Spirulina, and significantly enhanced 1,1-diphenyl-2-trinitrophenylhydrazine free-radical scavenging ability and total antioxidant ability. On the contrary, treatments with lactic acid bacteria and the mixture of lactic acid bacteria and Bacillus strains endowed the fermented supernatants with good antibacterial ability. The results showed that probiotic fermentation has a good effect on Spirulina and can serve as a new procedure for developing new Spirulina-containing food items.

The effect characteristics of temperature on stroke mortality in Inner Mongolia and globally.

The current study investigated the correlation between stroke mortality and temperature. Monthly and seasonal variations in stroke mortality were plotted and daily stroke-related deaths were calculated. The lag times were calculated using the time series analysis. The correlation between stroke incidence and the diurnal temperature range (DTR) was analyzed using case-crossover analysis. Global stroke mortality was described in five latitudes. In the eastern region of Inner Mongolia, the stroke mortality was 174.18/105, about twice of that of the midwestern regions (87.07/105), and temperature was negatively correlated with stroke mortality. Mortality peaked in the winter and troughed in the summer (χ2 = 13.634, P < 0.001). The days in which stroke-related deaths were greater than ten occurred between late October and early April. The effect of temperature on stroke incidence occurred during a lag time of 1 (P = 0.024) or 2 months (P = 0.039). A DTR over 13 °C was positively correlated (r = 0.95, P = 0.004) with stroke with a lag time of 1 day. The effect of temperature on stroke was shown to be the same for various populations. As the latitude increases, stroke mortality also increases with latitudes > 40°; the highest mortality was 188.05/105 at the highest latitude. Only in relatively cold regions as the temperature decreases does stroke mortality increase for various populations. Differences in the time lag as well as in the DTR lag and DTR critical point vary for both the temperature and region.

Immobilized enzyme on pulp fiber through layer-by-layer technique using cationic polyacrylamide for whitewater treatment from papermaking.

Anionic pectic substances in whitewater from papermaking are detrimental to machine operation and product quality. Pectinase was immobilized on pulp fiber using cationic polyacrylamide with layer-by-layer method to obtain bound enzyme with tunable activity and good performance for wastewater treatment. It was revealed that high charge density and low molecular weight for cationic polyacrylamide were advantageous for enzymatic activity. During the layer-by-layer adsorption process, the enzymatic activity of the immobilized enzyme increased nearly linearly with the layer number from 983 to 3074 U/g until the fourth layer. The stability of the four-layer immobilized enzyme was improved. The multilayer immobilized enzyme exhibited good reusability and storage stability compared with monolayer enzyme. At dosage of 10 U/mL, the cationic demand of the whitewater samples was reduced by 15% using four-layer immobilized enzyme. The results indicated a potential route to prepare immobilized enzyme with good performance for wastewater treatment in papermaking industry.