Metabolomics reveals the response of hydroprimed maize to mitigate the impact of soil salinization

Soil salinization is a major environmental stressor hindering global crop production. Hydropriming has emerged as a promising approach to reduce salt stress and enhance crop yields on salinized land. However, a better mechanisitic understanding is required to improve salt stress tolerance. We used a biochemical and metabolomics approach to study the effect of salt stress of hydroprimed maize to identify the types and variation of differentially accumulated metabolites. Here we show that hydropriming significantly increased catalase (CAT) activity, soluble sugar and proline content, decreased superoxide dismutase (SOD) activity and peroxide (H2O2) content. Conversely, hydropriming had no significant effect on POD activity, soluble protein and MDA content under salt stress. The Metabolite analysis indicated that salt stress significantly increased the content of 1278 metabolites and decreased the content of 1044 metabolites. Ethisterone (progesterone) was the most important metabolite produced in the roots of unprimed samples in response to salt s tress. Pathway enrichment analysis indicated that flavone and flavonol biosynthesis, which relate to scavenging reactive oxygen species (ROS), was the most significant metabolic pathway related to salt stress. Hydropriming significantly increased the content of 873 metabolites and significantly decreased the content of 1313 metabolites. 5-Methyltetrahydrofolate, a methyl donor for methionine, was the most important metabolite produced in the roots of hydroprimed samples in response to salt stress. Plant growth regulator, such as melatonin, gibberellin A8, estrone, abscisic acid and brassinolide involved in both treatment. Our results not only verify the roles of key metabolites in resisting salt stress, but also further evidence that flavone and flavonol biosynthesis and plant growth regulator relate to salt tolerance

Beef, Chicken, and Soy Proteins in Diets Induce Different Gut Microbiota and Metabolites in Rats

Previous studies have paid much attention to the associations between high intake of meat and host health. Our previous study showed that the intake of meat proteins can maintain a more balanced composition of gut bacteria as compared to soy protein diet. However, the associations between dietary protein source, gut bacteria, and host health were still unclear. In this study, we collected colonic contents from the growing rats fed with casein, beef, chicken or soy proteins for 90 days, and analyzed the compositions of gut microbiota and metabolites. Compared to the casein group (control), the chicken protein group showed the highest relative abundance of Lactobacillus and the highest levels of organic acids, including lactate, which can in turn promote the growth of Lactobacillus. The soy protein group had the highest relative abundance of Ruminococcus but the lowest relative abundance of Lactobacillus. Long-term intake of soy protein led to the up-regulation of transcription factor CD14 receptor and lipopolysaccharide-binding protein (LBP) in liver, an indicator for elevated bacterial endotoxins. In addition, the intake of soy protein also increased the levels of glutathione S-transferases in liver, which implicates elevated defense and stress responses. These results confirmed that meat protein intake may maintain a more balanced composition of gut bacteria and reduce the antigen load and inflammatory response from gut bacteria to the host

Analysis of the Umami and Aroma of Chicken Soup Made from Different Raw Materials and Comparison with Commercial Chicken Soups

With the aim of exploring the correlation between instrumental analysis and sensory evaluation of chicken soup umami-aroma characteristics, 110-day-old Xue Shan hens and 60-day-old 817 broilers were used as raw materials to prepare chicken soup, and four commercially available chicken soup products (C, G, T and W) were also selected to make analysis. The above six samples were tested with free amino acids, nucleotides, electronic tongue, electronic nose, free fatty acids, volatile substances, fuzzy sensory evaluation. Then partial least squares regression was used to explore the correlation between sensory evaluation and instrument analysis indexes. The results showed that the chicken soup of 817 broilers (S60) and Xue Shan hens (S110) was significantly lower in fresh amino acids, umami, and saltiness response values than the other four chicken soups (P<0.05). The S110 chicken soup was significantly higher in essential amino acids, total fatty acids content (72.600 mg/mL), and unsaturated fatty acids than the other five chicken soups (P<0.05). So, S110 chicken soup had the excellent aroma grade during sensory evaluation. However, the lack of umami and strong greasiness lowered the total sensory score of S110 sample. Wu Tai Po product (W) chicken soup had significantly higher levels of glutamic acid, fresh amino acid, umami, and saltiness response values than the other five chicken soups (P<0.05) and moderate total fatty acids content (52.200 mg/mL). Satisfied umami and aroma contributed to the highest overall sensory score of W chicken soup among all samples. As to Shen soup product (C), Tang Xiao Guan product (G) and Tang Xiao Tiao product (T) chicken soups, lower total fat and less umami resulted in their lower sensory scores among all samples. The partial least squares regression (PLSR) and Pearson correlation analysis showed highly significant positive correlation (P<0.01) among three types of indicators, including liking and taste of sensory evaluation, saltiness and umami response values of electronic tongue testing, glutamic acid and total fresh amino acids of free amino acids testing. There were highly significant positive correlation (P<0.01) between the indicators of aroma as well as floating oil and total fatty acids, unsaturated fatty acids as well as saturated fatty acids. In summary, ensuring moderate fat content can improve the overall sensory score by balancing umami and aroma. This study provides a reference for the research and regulation of chicken soup flavor, raw and auxiliary ingredients selecting and the personalized customization of chicken soup products

Trace element chemostratigraphy of two Ediacaran–Cambrian successions in South China: Implications for organosedimentary metal enrichment and silicification in the Early Cambrian

A trace element study is presented of two Ediacaran–Early Cambrian sedimentary successions in South China: the Shatan section, Sichuan Province, which represents a shallow platform setting, and the Songtao section, Guizhou Province, which corresponds to a more basinal, depositional environment. Across South China, sedimentary strata of this age exhibit characteristic trace metal enrichments in generally organic-rich, stratigraphically correlative, transgressive units. Trace element (including REE) data are used here to determine the palaeoenvironmental and diagenetic conditions during this Early Cambrian interval of metal scavenging that resulted in enrichments over grey shale of Mo > Cd > V > U >Ni > Ag > Zn > Cu > Pb. At Shatan, high organic carbon contents (up to 5% TOC) correlate with Mo enrichment, which indicates that metal scavenging was linked to organic productivity and decay. Low Th/U ratios are consistent with highly reducing conditions during metal scavenging, while extremely high V contents imply that bottom waters were possibly euxinic at times of extreme anoxia. At Songtao, very low Th/U ratios are strongly associated with high V/Sc and low δ13Corg, implying that anoxia, organic decomposition and metal sequestration were associated in the deepwater facies, too. There is no unambiguous trace element evidence that hydrothermal activity contributed to metal enrichment in South China during the Early Cambrian. The systematic relationship with ocean transgression suggests that enrichment was caused largely by oceanographic changes to organic productivity and burial rather than post-depositional fluid flow. Negative Ce anomalies and seawater-like REE distribution patterns are a feature of the Liuchapo chert and lower black shales of the Jiumenchong Formation at Songtao. Ce depletion indicates that authigenic components of these sedimentary units formed under oxic conditions, which contradicts the other geochemical redox proxies. We argue that this chert derived primarily from biogenic silica from siliceous plankton, which formed above a redox boundary within the water column. Neither silicification nor hydrothermal fluids, contrary to some published models, played a significant role in metal transport

Additional file 1: of The gut microbiota in young and middle-aged rats showed different responses to chicken protein in their diet

Table S1. Richness and diversity indexes relative to each sample. Table S2. The differentially fecal bacterial communities between Young-0d and Middle aged-0d using LEfSe at the OTU level. Table S3. The differentially fecal bacterial communities between Young-14d and Middle aged-14d using LEfSe at the OTU level. Table S4. The differentially fecal bacterial communities between Young-0d and Young-14d using LEfSe at the OTU level. Table S5. The differentially fecal bacterial communities between Middle aged-0d and Middle aged-14d using LEfSe at the OTU level. (DOC 254 kb

Intake of Meat Proteins Substantially Increased the Relative Abundance of Genus Lactobacillus in Rat Feces.

Diet has been shown to have a critical influence on gut bacteria and host health, and high levels of red meat in diet have been shown to increase colonic DNA damage and thus be harmful to gut health. However, previous studies focused more on the effects of meat than of meat proteins. In order to investigate whether intake of meat proteins affects the composition and metabolic activities of gut microbiota, feces were collected from growing rats that were fed with either meat proteins (from beef, pork or fish) or non-meat proteins (casein or soy) for 14 days. The resulting composition of gut microbiota was profiled by sequencing the V4-V5 region of the 16S ribosomal RNA genes and the short chain fatty acids (SCFAs) were analyzed using gas chromatography. The composition of gut microbiota and SCFA levels were significantly different between the five diet groups. At a recommended dose of 20% protein in the diet, meat protein-fed rats had a higher relative abundance of the beneficial genus Lactobacillus, but lower levels of SCFAs and SCFA-producing bacteria including Fusobacterium, Bacteroides and Prevotella, compared with the soy protein-fed group. Further work is needed on the regulatory pathways linking dietary protein intake to gut microbiota

Carbon isotopic evolution of the terminal Neoproterozoic and early Cambrian: Evidence from the Yangtze Platform, South China

Profound geotectonic, climatic and biological changes occurred during the terminal Neoproterozoic and its transition into the Early Cambrian. These changes are reflected in temporal variations of the carbon isotopic composition of seawater, recorded in a sedimentary succession on China's Yangtze Platform. However, in addition to secular changes in carbon isotopes, the studied succession reflects additional variations in accordance with the deposition in different sedimentary facies, ranging from shallow water platformal to deeper water basinal settings. Likely a consequence of incorporation of variable amounts of 13C depleted bacterial biomass, this regional signal is superimposed on the secular variations of the global carbon cycle

Comparative Proteomics Provides Insights into Metabolic Responses in Rat Liver to Isolated Soy and Meat Proteins

It has been reported that isolated dietary soy and meat proteins have distinct effects on physiology and liver gene expression, but the impact on protein expression responses are unknown. Because these may differ from gene expression responses, we investigated dietary protein-induced changes in liver proteome. Rats were fed for 1 week semisynthetic diets that differed only regarding protein source; casein (reference) was fully replaced by isolated soy, chicken, fish, or pork protein. Changes in liver proteome were measured by iTRAQ labeling and LC–ESI–MS/MS. A robust set totaling 1437 unique proteins was identified and subjected to differential protein analysis and biological interpretation. Compared with casein, all other protein sources reduced the abundance of proteins involved in fatty acid metabolism and Pparα signaling pathway. All dietary proteins, except chicken, increased oxidoreductive transformation reactions but reduced energy and essential amino acid metabolic pathways. Only soy protein increased the metabolism of sulfur-containing and nonessential amino acids. Soy and fish proteins increased translation and mRNA processing, whereas only chicken protein increased TCA cycle but reduced immune responses. These findings were partially in line with previously reported transcriptome results. This study further shows the distinct effects of soy and meat proteins on liver metabolism in rats

Effects of Dietary Protein from Different Sources on Biotransformation, Antioxidation, and Inflammation in the Rat Liver

In this work, the effects of different sources of meat protein on liver metabolic enzymes were investigated. Rats were fed for 90 days with semisynthetic diets in which casein was fully replaced by isolated soybean, fish, chicken, pork, or beef proteins. Then, liver proteomics was performed using iTRAQ and LC–ESI–MS/MS. The results indicated that intake of meat protein diets significantly reduced the protein levels of CYP450s, GSTs, UGTs, and SULTs compared to those of the casein and soybean protein diet groups. The total antioxidant capacity and lipid peroxidation values did not differ between four meat protein diet groups and the casein diet group. However, GSH activity in the fish, chicken, and beef protein groups was significantly higher than those of the casein and soybean protein groups. The beef protein diet significantly upregulated the expression of immune-related proteins. The Keap1-Nrf2-ARE signaling pathway was suggested to involve the diet-mediated regulation of biotransformation, inflammation, and redox status