Effect of Extraction Temperature on the Functional and Structural Properties of Mullet Scale Gelatin

The functional property is an important factor to measure the quality of fish gelatin, which directly relates to the practical application range and value of fish gelatin. In order to explore the effect of extraction temperature on the functional properties of mullet scale gelatin, this study used a hot water extraction method. Different temperatures (60, 70, 80, 90, 100 ℃) were examined to assess their impact on the surface morphology of fish scales, fish scale gelatin yield, and functional properties (foaming capacity, emulsifying activity, gel strength, gel temperature, and melting temperature). Furthermore, the structural characteristics of fish scale gelatin were investigated using SDS-PAGE, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results showed that as the extraction temperature increased from 60 ℃ to 100 ℃, the damage to the surface of mullet scales became increasingly severe. The fish scale gelatin yield increased from 31.72% to 50.97%, foaming capacity improved from 23.33% to 73.33%, and emulsifying activity increased from 15.13 m2/g to 17.27 m2/g. However, gel strength, gel temperature, and melting temperature decreased from 677.82 g, 20.80 ℃, and 28.70 ℃ to 372.91 g, 15.80 ℃, and 23.90 ℃, respectively. Additionally, with the increase in extraction temperature, the characteristic bands of mullet scale gelatin α1, α2, and β chains on the electrophoresis pattern became increasingly blurred. The infrared spectroscopy results showed that the fish scale gelatin had characteristic absorption peaks (amide A, amide Ⅰ, amide Ⅱ, and amide Ⅲ), with the wavenumber of amide A first increasing and then decreasing. The scanning electron microscopy results showed that the tightness of the porous grid structure of the fish scale gelatin decreased. These findings provide a theoretical basis for the industrialization of mullet scale gelatin

Review of the Spatial Distribution, Source and Extent of Heavy Metal Pollution of Soil in China: Impacts and Mitigation Approaches

Background. China has undergone a rapid industrial revolution and urbanization during the past three decades. This expansion is largely responsible for the release of a large amount of heavy metals into soils and is increasingly raising concerns over the potential effects on human health and the environment. The problem is drawing increasing attention, especially after an extensive nationwide soil survey report in 2014. A number of studies have examined soil contamination by heavy metals in China. However, most of these studies have been small in scale and it is therefore challenging to get a general overview of the level of contamination across the entire country. Objectives. The present study is aimed at presenting a synthesized overview of the extent, pattern, and impact of heavy metal contamination of soils in China, including mitigation approaches. Methods. Eighty-six journal articles and other literature such as reports, internet sources, and statistical yearbooks were narratively and critically synthesized to compile a holistic summary of sources of heavy metals, the extent of pollution, spatial distribution and impact of heavy metal contamination in China. The major findings from these studies are presented, along with mitigation approaches applicable to China. Discussion. A synthesis of major findings from recent scientific journals shows that about 10.18% of farmland soils which supports 13.86% of grain production in China is affected by heavy metals. The main sources of pollution are anthropogenic activities. Even though the spatial distribution of pollution is highly variable owing to natural and human factors, provinces with intensive industrial activities such as Henan, Shandong, and Sichuan are more highly polluted than others. These regions are top grain producing areas and hence require close follow-up for development of feasible approaches to mitigating crop contamination and associated health risks emerging in parts of China. The government recently launched a program aimed at determining sound reclamation strategies. Conclusion. Mitigation of heavy metal contamination in China requires coordination of different actors and integration of all feasible reclamation approaches. Competing Interests. The authors declare no competing financial interests

Effect of Grass Carp Scale Collagen Peptide FTGML on cAMP-PI3K/Akt and MAPK Signaling Pathways in B16F10 Melanoma Cells and Correlation between Anti-Melanin and Antioxidant Properties

Peptide Phe-Thr-Gly-Met-Leu (FTGML) is a bioactive oligopeptide with tyrosinase inhibitory activity derived from gelatin hydrolysate of grass carp scales. Previous studies have shown that FTGML addition can effectively inhibit mushroom tyrosinase activity in vitro, and also has some effect on the inhibition of melanogenesis in zebrafish in vivo, but the underlying mechanism is not fully understood. In this study, we used FTGML to treat B16F10 melanoma cells, and found a significant inhibition of tyrosinase activity and melanin synthesis. Interestingly, the treatment showed a strong correlation between antioxidant activity and anti-melanin, which was associated with FTGML reducing the involvement of reactive oxygen species in melanin synthesis. Furthermore, FTGML reduced melanogenesis in B16F10 cells by downregulating the cAMP-PI3K/Akt and MAPK pathways (p38 and JNK). These results suggested that FTGML can reduce melanin production in mouse B16F10 melanoma cells through multiple pathways

Sources, Spatial Distribution and Extent of Heavy Metals in Relation to Land Use, Lithology and Landform in Fuzhou City, China

Assessing the spatial distribution of soil heavy metals in urban areas in relation to land use, lithology and landform may provide insights for soil quality monitoring. This study evaluated the spatial distribution, the sources and the extent of heavy metal(loid)s in the topsoil of Fuzhou city, China. A combination of GIS and multivariate approaches was used to determine the spatial distribution and the sources of heavy metals. Additionally, analysis of variance was used to determine the variability of selected heavy metals across land use, landform, and lithology. The result show that the mean concentrations of Cd, Zn, As and Pb were higher than background values. Most of the heavy metals had significant correlations with each other. In particular, V and Fe (0.84 at p < 0.01) and Ni and Cr (0.74 at p < 0.01) had strong correlations, while Cu and Fe (0.68 at p < 0.01), Cu and V (0.63 at p < 0.01), Cu and Co (0.52 at p < 0.01), Zn and Ni (0.51 at p < 0.01), Co and Fe (0.54 at p < 0.01), and Cu and Zn (0.55 at p < 0.01) had moderate correlations. Arsenic, Cu, and Zn had significant positive correlations with total nitrogen (TN). Similarly, arsenic, Zn and Cr had positive correlations with total carbon (TC), while Co had negative correlations with TN and TC at p < 0.01. The peak values for Cr, Ni, Pb, Mn, and Zn were observed in the intensively urbanized central and eastern parts of the study area, suggesting that the main sources might be anthropogenic activities. Agricultural land use had the highest content of Cd, which may be attributed to the historical long-term application of agrochemicals in the area. Additionally, its content was significantly higher in agricultural land use with shale lithology, implying that shale lithology was a key geogenic source for Cd of soils in the study area. Pb content was affected by urban land use, which may be attributed to intensive human activities such as emissions from vehicles, industrial effluents, mining activities, and other discharges. The results show the high spatial variability of heavy metal(loid)s, implying that the soils in the study area were highly influenced by both geogenic variability and human activities. Moreover, land use and lithology had significant impacts on the variability of Cd, As and Pb. Sustainable agricultural practices and urban management are recommended to sustain the eco-environment of coastal city

Modeling the Spatial Dynamics of Soil Organic Carbon Using Remotely-Sensed Predictors in Fuzhou City, China

Assessing the spatial dynamics of soil organic carbon (SOC) is essential for carbon monitoring. Since variability of SOC is mainly attributed to biophysical land surface variables, integrating a compressive set of such indices may support the pursuit of an optimum set of predictor variables. Therefore, this study was aimed at predicting the spatial distribution of SOC in relation to remotely sensed variables and other covariates. Hence, the land surface variables were combined from remote sensing, topographic, and soil spectral sources. Moreover, the most influential variables for prediction were selected using the random forest (RF) and classification and regression tree (CART). The results indicated that the RF model has good prediction performance with corresponding R2 and root-mean-square error (RMSE) values of 0.96 and 0.91 mg·g−1, respectively. The distribution of SOC content showed variability across landforms (CV = 78.67%), land use (CV = 93%), and lithology (CV = 64.67%). Forestland had the highest SOC (13.60 mg·g−1) followed by agriculture (10.43 mg·g−1), urban (9.74 mg·g−1), and water body (4.55 mg·g−1) land uses. Furthermore, soils developed in bauxite and laterite lithology had the highest SOC content (14.69 mg·g−1). The SOC content was remarkably lower in soils developed in sandstones; however, the values obtained in soils from the rest of the lithologies could not be significantly differentiated. The mean SOC concentration was 11.70 mg·g−1, where the majority of soils in the study area were classified as highly humus and extremely humus. The soils with the highest SOC content (extremely humus) were distributed in the mountainous regions of the study area. The biophysical land surface indices, brightness removed vegetation indices, topographic indices, and soil spectral bands were the most influential predictors of SOC in the study area. The spatial variability of SOC may be influenced by landform, land use, and lithology of the study area. Remotely sensed predictors including land moisture, land surface temperature, and built-up indices added valuable information for the prediction of SOC. Hence, the land surface indices may provide new insights into SOC modeling in complex landscapes of warm subtropical urban regions

Geraniol-Mediated Suppression of Endoplasmic Reticulum Stress Protects against Cerebral Ischemia–Reperfusion Injury via the PERK-ATF4-CHOP Pathway

Endoplasmic reticulum (ER) stress plays an important role in cerebral ischemia–reperfusion injury (CIRI). Geraniol has antioxidant, antibacterial, and anti-inflammatory activities. Studies have shown that geraniol has a protective effect against CIRI in rats, but the exact mechanism is unclear. Purpose: The aim of this study was to investigate the protective mechanism of geraniol against CIRI. We established a middle cerebral artery occlusion reperfusion model in rats and a PC12 cell oxygen–glucose deprivation/reoxygenation (OGD/R) model to observe the neuroprotective effects of geraniol. Neurological scoring, 2,3,5-triphenyltetrazolium chloride staining, and hematoxylin and eosin staining were used to evaluate the neuroprotective effects of geraniol against CIRI. ER-stress-related and apoptosis-related protein expression was detected via Western blotting and immunofluorescence. Apoptosis was also detected via TUNEL assays and flow cytometry. The fluorescent detection of intracellular calcium was achieved using fluorescent calcium-binding dyes, and transmission electron microscopy was used to assess the neuronal ultrastructure. Geraniol effectively attenuated cerebral infarction and pathological injury after CIRI, had a protective effect against CIRI, significantly reduced the expression of the ER-stress-related proteins P-PERK, ATF4, CHOP, and GRP78 and the pro-apoptotic protein BAX, increased the expression of the anti-apoptotic protein BCL-2, and reduced the occurrence of apoptosis. In the OGD/R model in PC12 cells, the protective effect of geraniol was the same as that in vivo. Our results suggest that geraniol has a protective effect against ischemic stroke by a mechanism possibly related to ER stress via the PERK-ATF4-CHOP pathway

Temporal-spatial Distribution Characteristics of Air Pollutants in Chengdu Economic Region, China

The previous characteristics researches of air pollution were almost based on data from national environmental monitoring stations in 2015. The temporal variation curves of air pollutants and the ArcGIS grid interpolation method were used to analyze the spatial-temporal variation of air pollutants in five cities of Chengdu economic region. In 2015, the monthly change trends of PM2.5, PM10, CO, NO2 and NO of air pollutants in Chengdu economic region were basically the same. The maximum monthly average concentration was in January or December, and the minimum was in May to September. The temporal variation of SO2 was characterized by little fluctuation of monthly concentration. The temporal variation characteristics of O3 were opposite to other pollutants. The spatial distribution of PM10 and PM2.5 was characterized by the largest concentration in Chengdu and the southwest of Meishan, in which they were mainly concentrated in the central area of Chengdu in winter. The average concentration of CO in Chengdu was the largest, followed by Deyang and Mianyang, and Meishan and Ziyang was the smallest. The concentrations of NO2 and NO in Chengdu were the largest, while those in Ziyang were the smallest. The spatial distribution characteristics of O3 were different from other pollutants. The areas with the largest concentration of O3 were Ziyang and a small part of west in Chengdu. The spatial distribution of SO2 was characterized by the largest concentration of SO2 in Ziyang, the lowest concentration in Mianyang and Deyang