Physicochemical Characteristics of Orange Juice Samples From Seven Cultivars

Some physicochemical parameters of orange juice from seven orange varieties （Pineapple orange, Hamlin, Trovita, Jincheng, 1232 Tangor, Olinda Valencia, and Delta Valencia） were analyzed, special attention was paid to the level of sugars, organic acids, free amino acids, mineral composition, and color parameters. The results showed that total soluble solids （TSS）, TSS/titratable acidity （TA） ratios, sugars, and organic acids were kept within a proper range for juice processing except that Jincheng had lower TSS than the others. Sucrose was the most dominant sugar in the orange cultivars, followed by fructose and glucose, while citric acid was the principal organic acid. Serine and proline were the principal amino acids. Potassium was the most abundant mineral in all of the juice samples, followed by magnesium and calcium. The sodium content of most varieties was under 10 mg kg^-1. Though all of the samples had orange colour, Olinda Valencia and Delta Valencia had deeper red colour than the others. Statistically significant differences （P〈 0.05） were found between the samples in most of the characteristics. The results provided important information on the physicochemical characteristics of the varieties and on how to make the best use of orange cultivars for different purposes, which is of significance for both technological research and processing practice.

Extraction and physicochemical characteristics of a red pigment produced by marine bacterium strain S - 9801

A red pigment that has better biological properties is produced by marine bacterium strainS- 9801. The extraction methods, physicochemical and toxicity of the pigment have been studied. Dissolubility of pigment in the five organic solvent has been tested, and ethanol is optimally chosen for extraction. Physicochemical characteristics of this pigment was stable. The absorbance of the pigment solution was no losing when put under natural light for 10 days or treated by UV for 30 minutes, color of the pigment unchanged after 100℃ hythere for 1 h or 80 ℃ xerother for 2 h. The median lethal dose (LD_50) of the rat by celiac injection was 670.04 mg/kg and minimum lethal dose of oral was greater than 2 000 mg/kg.

Review on the Analysis and Research of Fog Physicochemical Characteristic Observation

[Objective] The research aimed to review the analysis and research on the physicochemical characteristic observation aspect of fog. [Method] To understand the roles of fog microphysical characteristic and chemical reaction on the formation, dissipation, development of fog, the interaction between the microphysical structure, chemical characteristic of fog and the aerosol in the environment, the analysis and research on the micro-physicochemical observation aspect of fog were mainly introduced here. We also put forward that the field still needed the deep research content. [Result] The observation and research on the micro-physicochemical characteristics of fog could reveal the mechanisms of fog formation, dissipation, development from the microphysical components and the reaction of chemical composition. The previous researches focused on the concentration of micro-fog droplet, the particle size of fog droplet, the liquid water content in the fog, the particle concentration, size, chemical component and reaction of aerosol. It included the evolution and interaction between the microscopic quantities in the fog, the relationship between the microscopic quantity and the visibility. As the improvements of observation experiment instruments and sampling method, it recognized that the fog in the polluted environment condition and the clean air had the obvious difference whether in the microphysical characteristic or the chemical component. The particle concentration, chemical component and liquid water content of fog were all depended on the fog particle size. The interaction between the radiation, turbulent flux and the micro-physical characteristics of fog, the vertical structure of microphysics in the fog, the interaction between the chemical components, the relationship between the microphysical quantity and the macro-physical quantity (such as the visibility), the precision of experimental instrument, etc. needed the further research. [Conclusion] The research provided the comprehensive knowledge for the characteristic analysis and forecast of fog.

Physicochemical properties and biological activities of polysaccharides from the peel of Dioscorea opposita Thunb.extracted by four different methods

Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP.

Comparison of Physicochemical,Organoleptic and Nutritional Abilities of Eight Sweet Potato(Ipomoea batatas)Varieties

In Martinique (F.W.I.), biodiversity of vegetable varieties remain unexploited due to public unawareness or supply problems. To further enhance the sweet potato, physicochemical, sensory and nutritional characteristics of eight varieties of sweet potato were established. The eight sweet potatoes cultivars were noticeably diverse with phenotypic, sensory, physicochemical and nutritional characteristics which were very varied. The eight cultivars grown in Martinique were advantageously positioned in relation to the globally identified sweet potato, regarding fibre, starch, potassium, copper, vitamin B1, B3 and B9 contents. Compared to the ordinary potato, Martiniquan sweet potatoes have a much better nutritional potential. Energy value and vitamin C levels were twice as much as in normal potatoes. Martiniquan sweet potatoes cultivars were also richer in minerals and vitamins, with 2.7 times more vitamin B9 and 63 times more beta-carotene than the ordinary potato.

Significant changes in arbuscular mycorrhizal community and soil physicochemical properties during the saline-alkali grassland vegetation succession

Arbuscular mycorrhizal(AM)fungi are widely distributed in various habitats,and the community composition varies in response to the changing environmental conditions.To explore the response of community composition to the succession of saline-alkali land,soil samples were collected from three succession stages of Songnen saline-alkali grassland.Subsequently,the soil characteristics were determined and the AM fungi in soil samples were analyzed by high-throughput sequencing.Then,the response relationship between community composition and soil characteristics was studied by Canonical correlation and Pearson analyses.The soil properties improved with the succession of saline-alkali grassland.There was no significant difference in alpha diversity between the first and second succession stage(Suaeda glauca and Puccinellia tenuiflora,respectively),and the microbial community had a dense association network at the third stage(Leymus chinensis);in addition,each succession stage had significantly enriched amplicon sequence variants(ASVs)and functional pathways.All the soil properties except cellulase activity had significant effects on community composition.Furthermore,the pH,organic carbon,organic matter,and sucrase activity significantly correlated with alpha diversity indices.These results provide a theoretical basis for realizing the significant changes in AM fungal community and soil properties during the saline-alkali grassland vegetation succession.

Impact of Single Wavelength (532 nm) Irradiation on the Physicochemical Properties of Sesame Oil

This paper investigates the influence of green laser (532 nm) radiation on some physicochemical properties of sesame oil before and after storage period of 15 consecutive days. The samples of sesame oil were irradiated with diode laser beam with wavelength 532 nm and 1 W output power, to duration times of 10, 20, 30, 40, 50 and 60 minutes, and kept for a storage period of 15 consecutive days along with an untreated control at ambient conditions. Physicochemical properties like acid value, ester value, free fatty acids, peroxide value, density, refractive index, viscosity, and moisture of sesame oil were studied. Fourier transform infrared spectroscopy was used to evaluate the degree of oxidation after irradiation processes. Their properties were compared at the 1st and 15th day of storage. Study reveals that green laser irradiation increases ester value, saponification, acid value, free fatty acids, peroxide value, viscosity and moisture content of sesame oil;while, it slightly changes refractive index and density. Study also indicates that the storage period of 15 days decreases the ester value, saponification value, and moisture content;while, it accelerates acid value, free fatty acid, peroxide value, density viscosity, and slightly increases the refractive index. Meanwhile, FTIR spectra of the stored samples revealed a notable difference due to the green laser irradiation and storage. These results suggest that exposing sesame oil to the green laser irradiation influences their oxidation stability and quality.

Comparative Study on the Structural and Physicochemical Properties of Flour and Starch from Dioscorea opposita Thunb

The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total starch and amylose content as compared to DF. Starch granules of DF were oval shape with rough surface while DS and PDS were relatively smooth by SEM. According to XRD measurements, FT-IR spectroscopy and 13 C CP/MAS NMR spectroscopy, all samples displayed C-type crystalline pattern, and PDS displayed the highest relative crystallinity and short-range order structure. However, DF contained the greatest content of the amorphous-phase. DF displayed the absorption peaks at 1730 and 1560 cm^-1 related to the characteristic groups of lipid and protein using FT-IR spectroscopy. Furthermore, DF exhibited significantly higher pasting temperature while DS displayed the great peak and breakdown viscosity, as well as PDS had the highest setback and final viscosity, presumably due to the chemical composition and structural differences. DF exhibited the highest gelatinization temperature whereas PDS displayed the greatest gelatinization enthalpy. The pasting and gelatinization properties of flour and starch might be related to the relative crystallinity, short-range order structure or the interactions between starch and its associated compounds. The results allow the improvement in the manufacture of Dioscorea opposita Thunb. flour and starch with desirable pasting and gelatinization properties.

Fog Research in China:An Overview

Fog can adversely affect human activity directly and indirectly, resulting in large losses both in terms of the local economy and lives. Much effort has been devoted to studies of fog across many areas of China, and in that context this paper aims to summarize climatic characteristics and review fog field experiments and their major results relating to fog mechanisms, physical properties and chemical characteristics. Progress in the application of remote sensing techniques and numerical simulation in fog research are also discussed. In particular, the effects of urbanization and industrialization on fog are highlighted. To end, perspectives on future fog research are outlined. The goal of this review paper is to introduce fog research in China to the global academic community and thus promote international collaboration on fog research. This is important because most papers on fog in China are published in Chinese, which are unreadable for the vast majority of non-Chinese researchers.

Comparison of soil bacterial diversity and community composition between clear-cut logging and control sites in a temperate deciduous broad-leaved forest in Mt. Sambong, South Korea

Deforestation or clear-cut logging affects forest ecosystems,including soil microbial communities.The purpose of this study was to investigate the effects of clearcut logging on the soil bacterial community in a temperate deciduous broad-leaved forest on Mt.Sambong,South Korea.We investigated the physicochemical characteristics and bacterial diversity of the soil in clear-cut logging and control sites.The available phosphorus(AP)level in soil was significantly lower in the clear-cut sites than in the control;however,the other physicochemical properties of soil were similar at the two sites.By examining the bacterial 16S rRNA gene using next-generation sequencing,we found that the number of bacterial taxa at the species and phylum level were similar at the control and clear-cut sites.Consistent with the high resilience of bacterial communities and absence of change in the soil physicochemical properties—with the exception of AP—we found similar levels of bacterial diversity at the two sites.Although most taxa showed similar composition ratios at the control and the clear-cut sites,some taxa such as Deltaproteobacteria,Ktedonobacteriales,Myxocccales,Polyangiaceae,Pedosphaera_f,and Solibacter showed differences after clear-cut logging.We conclude that AP was significantly associated with those bacterial taxa that showed differences in their composition ratios following clear-cut logging.

Red cabbage washing with acidic electrolysed water:effects on microbial quality and physicochemical properties

The effects of acidic electrolysed water(AEW)as‘green’technology on the microbiological and physicochemical properties of fresh-cut red cabbages were studied.Fresh-cut red cabbages and artificially inoculated red cabbages with Salmonella typhimurium DT104 were washed with distilled water(DW)and different available chlorine concentrations(ACC)of AEW for different times.AEW treatments significantly reduced the populations of native aerobic bacteria,molds,and yeasts,and artificially inoculated S.typhimurium DT104 compared with the DW-treated and untreated red cabbage samples.The effectiveness of AEW treatments was greatly enhanced with increasing ACC and treatment times.S.typhimurium DT104 were not detected in the washing water that were collected after the red cabbages treated by AEW.The surface colour,pH,and total phenolic contents did not significantly change when the red cabbages were washed with DW and AEW containing 100 mg/L available chlorine for 3 min.The anthocyanin contents and antioxidant activities of red cabbage were significantly reduced by 18.5 per cent for cyanidin,22.1 per cent for pelargonidin,and 11.2 per cent for 2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging activity,however,the impacts on the nutritional benefits of red cabbage were considered as limited and acceptable.The optimal process condition of AEW for washing red cabbage was 100 mg/L ACC for 3 min.In these conditions,most of the native microflora were inactivated,and artificially inoculated S.typhimurium DT104 on the red cabbage were reduced by 40.2 per cent[3.67 log CFU/g(log10 colony-forming units per gram)]and with minimal losses of nutrients and antioxidant activity,as well as no requirement of decontamination treatment on the washing water after AEW treatment.

Preparation,physicochemical and structural characterizations,and bioactivities of polysaccharides from Corbicula fluminea industrial distillate

Corbicula fluminea distillate(CFD),as an industrial sub-product of the steaming process of C.fluminea,is rich in polysaccharides,proteins,and amino acids and has important developmental value.In this study,therefore,three water-soluble polysaccharides(CFDPs:CFDP-D,CFDP-U,and CFDP-T)were extracted and separated from CFD through direct ethanol precipitation,ultrasound-assisted extraction,and three-phase partitioning(TPP),respectively.Results demonstrated that the three extraction methods had important influences on extraction yields,chemical compositions,molecular weights,monosaccharide and amino acid constituents,structural characteristics,and microstructures as well as biological activities of CFDPs.Specifically,CFDP-T had higher yield(60.92%±3.58%),carbohydrate content(91.05%±1.22%),and uronic acid content(8.55%±0.18%)and lower protein content(7.15%±0.15%)than CFDP-D and CFDP-U.The three CFDPs were acidic proteoheteroglycans combined through O-glycosidic bonds and had high molecular weights of 1.93–2.41×10^(7) Da and the same monosaccharide and amino acid compositions but different contents.Compared with CFDP-D and CFDP-U,CFDP-T exhibited more excellent free radical scavenging and stimulating(1.57±0.03μM,500μg/mL)activities on RAW264.7 macrophages in vitro.Therefore,our findings suggested that CFDP-T obtained from CFD by TPP had the potential to be a functional food ingredient in food industry.

中国北方沙漠河岸沙丘地球化学特征及其物源指示意义

Rivers in deserts present unique geographical features owing to aeolian-fluvial interactions.In this study,510 surface sediment samples were gathered from eight watersheds to systematically examine the major element characteristics of riparian sand dunes in northern China deserts.The findings revealed that these dunes could be categorized into three primary zones:Type I,comprising Keriya,Tora,Heihe,and Langqu rivers in the west;TypeⅡ,featuring the Maquan River in the Tibetan Plateau;and TypeⅢ,including Mu Bulag,Kuye,and Xar Moron rivers in the east.Specifically,the TypeⅢregion is characterized by a limited fresh material supply,a relatively high Chemical Index of Alteration(CIA),and the influence of nearby rivers on the provenance of riparian dunes,leading to a higher degree of chemical weathering than that of TypeⅠin the west.Notably,TypeⅡis marked by weak-moderate chemical weathering degree and a comparatively higher CIA value.These classifications and their difference of degree of chemical weathering are possibly governed by the type of parent rock and the availability of material.This research offers new insights into the classification of riparian dunes impacted by aeolian-fluvial interactions in arid regions of the northern China deserts.Furthermore,it provides valuable implications for studies focusing on the provenance of sediments.

Integrated analysis reveals an association between the rhizosphere microbiome and root rot of arecanut palm

The rhizosphere microbial community is crucial to plant health.Many studies have explored the association between the rhizosphere microbiome and plant disease.However,few studies have focused on root rot in arecanut palm,a disease causing devastating effects and thus resulting in economic losses that considerably affect the development of the arecanut industry.Here,rhizosphere samples were collected from both healthy arecanut palm plants and root-rotted arecanut palm plants,and the microbial communities were analyzed using high-throughput sequencing.The root-rotted samples exhibited distinct microbial community richness,diversity,and composition compared with the healthy samples,which was associated with p H according to the Mantel test.Identified potential plant pathogens,including Proteobacteria,Bacteroidetes,Chytridiomycota,and Mortierellomycota,were significantly enriched in the root-rotted samples.In contrast,potentially beneficial plant microbes,such as Acidobacteria and Gemmatimonadetes,were significantly depleted in the root-rotted samples.Co-occurrence networks were constructed to further identify microbial relationships in the root-rotted samples.These findings revealed ecological imbalance among beneficial bacteria in the root-rotted samples.The present study therefore provides an integrated view of the association between the microbial community and root rot in arecanut palm.