Continuous Extraction Method Research Articles

Continuous Extraction and Continuous Backfill Mining Method Using Carbon Dioxide Mineralized Filling Body to Preserve Shallow Water in Northwest China

The exploitation and utilization of coal resources are not only prone to causing water table lowering, but also produce a large amount of CO2 and coal-based solid waste. A scientific concept that employs the CO2 and solid wastes to develop filling bodies and inject them into the mined-out area, to sequestrate CO2 and mitigate the overburden migration and thus preserve the overlying aquifer, is proposed. Continuous extraction and continuous backfill (CECB) mining was selected as the mining method to meet the aforementioned objectives. Additionally, carbon dioxide mineralized filling body (CMFB) under ambient temperature and pressure was developed, with fly ash as aggregate, and CO2 gas, silicate additives and cement as accessories. The uniaxial compressive strength (UCS) and tensile strength of CMFB with various curing times and fly ash contents were tested indoors. A physical analogue simulation and FLAC3D numerical calculation were then successively implemented on the premise of determining a similar material ratio of CMFB in analogue simulation and calibrating the parameters of the CMFB in numerical simulation. The deformation of aquifuge and water level lowering while using CECB and CMFB with various proportion of fly ash were obtained. When using the CMFB with 75% fly ash content and 28 d curing time, the maximum values of vertical displacement, horizontal displacement, inclination, horizontal deformation and curvature of aquiclude were 26 mm, 6.5 mm, 0.12 mm/m, 0.08 mm/m and 0.0015 mm/m2, respectively, and the water table decreased 0.47 m. The results show that the CMFB with 75% fly ash is the most appropriate ratio to realize water preservation mining, CO2 sequestration and harmless treatment of solid wastes, contributing to the green and sustainable development of coal areas.

The Variation of Soil Phosphorus Fractions and Microbial Community Composition under Consecutive Cucumber Cropping in a Greenhouse

The distribution of phosphorus (P) fractions in soil plays a decisive role in soil P bioavailability; however, the characteristics of soil P fractions under consecutive cropping in a solar greenhouse remain unclear. To evaluate the effects of the long-term successive vegetable cropping on soil P fractions and the microbial community composition in greenhouse soil, a continuous long-term cropping experiment was conducted using cucumber (Cucumis sativus L.) in a solar greenhouse starting from 2006 to 2018. Soil P fractions and the microbial community composition were determined using the Hedley continuous extraction method and the phospholipid fatty acid (PLFA) method, respectively, in the 1st, 9th, 13th, and 21st rounds of cultivation. The soil total phosphorus (TP) content increased from 0.90 g·kg−1 in the 1st round to 3.07 g·kg−1 in the 21st round of cucumber cultivation. With an increase in continuous cropping rounds, soil available phosphorus (AP) increased and the phosphorus activation coefficient (PAC) decreased, with no significant difference between the 13th and 21st rounds. After 21 rounds of continuous cropping, the soil organic matter (SOM) content was 16.34 g·kg−1, 1.42 times that of the 1st round. The abundance of soil bacteria, actinomycetes, Gram-negative bacteria (G−), Gram-positive bacteria (G+), and total PLFAs initially increased with continuous cropping rounds, but then decreased significantly, and the ratios of fungi:bacteria (F/B) and G+/G− bacteria also increased significantly with continuous cropping rounds. The contents of soil labile P, moderately labile P, and non-labile P increased significantly over 21 continuous cropping rounds. Together, these results demonstrate that long-term continuous cropping can directly lead to the accumulation of P fractions, but it can also affect the abundance of actinomycetes through SOM enrichment, which indirectly leads to the accumulation of non-labile P. This study provides a theoretical basis for future soil P fertilizer management and vegetable production sustainability.

Antibacterial Activity of Shwetavarshabuvadi Formulation Extracts on Various Pathogens Causing Skin and Soft Tissue Infections – An In Vitro Study

Introduction: The present study was carried out with an objective to investigate the antimicrobial potentials of various extracts of Shwetavarshabuvadi formulation on common pathogens causing skin and soft tissue infections. Methods: Aqueous and ethanolic extracts of study formulation with three concentrations 10%, 20%, 30% were prepared using Continuous extraction method by Soxhlet Apparatus. All extracts were tested against Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), and Pseudomonas aeruginosa (ATCC 27853). The susceptibility tests were performed using Agar ditch method. The antibacterial activity was assessed on the basis of Zone of inhibition and activity index. Results : As compared with standard drug (doxycycline), the results revealed that all extracts possesses anti-bacterial activity in dose dependent manner but aqueous extract was found to have maximum activity against all pathogens taken in this study. Maximum antibacterial activity was reported against S.aureus followed by P.aeruginosa by all extracts. E.Coli was resistant at 10 % conc. of both extracts of the study formulation. Conclusion: In vitro findings of this study confirmed antibacterial activity of Shwetavarshabuvadi formulation on common pathogens causing skin and soft tissue infections.

Study on Speciation Chemical Analysis of Rare Earth Elements in Soil Based on Green Environmental Technology

The impact of rare earth elements on the soil environment is not only related to its total amount, but also more closely related to its chemical form. The green and environmentally friendly acid digestion and morphological continuous extraction methods were used to extract and analyze the total amount of rare earth elements and the forms of rare earth elements in the soil samples. Inductively coupled plasma mass spectrometry was used to determine the content of rare earth elements and the content of rare earth elements in the soil samples. Form content. The results show that the content of rare earth elements in the collected soil samples is 200-1418mg/kg, and the content of light rare earth elements is much higher than that of heavy rare earth elements; the recovery rate of the sum of the combined forms of rare earth elements relative to the total amount is 88.2% to 110%, indicating that the continuous extraction method is suitable for the analysis of rare earth elements in soil samples. The rare earth elements in soil samples mainly exist in the residue state, which is 33%-80%; the co-precipitation state of crystalline iron and manganese hydroxide is 10%-31%; the adsorption state of humus and amorphous oxide is 5.0%-18%; The exchange state and the carbonate combined state are 4.0% to 23%; the amorphous iron-manganese oxide co-precipitation state is less than 3%. The influence of the location of the sampling point and the nature of rare earth elements on the content of rare earth elements was analysed, and the influence of soil properties on the distribution of morphology was discussed.

In-vitro hypoglycemic activity of lawsonia inermis Linn. Leaf extracts

in-vitro hypoglycemic activity of lawsonia inermis Linn. Leaf extracts

Effects of exogenous addition of cadmium on cadmium speciation in hyperaccumulator of Sedum alfredii Hance

Continuous chemical extraction is considered to be one of the most common methods for the extraction of heavy metals speciations in plants. However, the basis for the extraction order of this method is not explained and has been rarely studied. In this paper, we analyzed the speciations of cadmium in plants by a four-step continuous extraction method. The extraction sequence of ethanol and water was studied to study the effect of extraction sequence on the extraction rate of extraction agent. The results showed that cadmium exists mostly in NaCl extraction state and the extraction rate of the two kinds of extraction agents decreased when the order of ethanol and water was changed.

A Catalyst-Free, Temperature-Driven One-Pot Synthesis of 1-Adamantylhydrazine Hydrochloride

1-Adamantylhydrazine can be a versatile intermediate for many biologically active compounds as adamantyl possesses a wide spectrum of medicinal properties. Described here is a detailed one-pot synthesis of 1-adamantylhydrazine, carried out on a milligram to gram scale, that steadily delivers a highly stable product used to carry out the synthesis of 1-(adamantan-1-yl)-1H-pyrazol-3-amine for bacterial studies. The reaction employs inexpensive, catalyst free, readily available starting materials. In the synthesis of 1-(adamantan-1-yl)-1H-pyrazol-3-amine, the use of a continuous extraction method allows for complete extraction of the target product into the organic layer and increases the overall percentage yield.

Kaempferol separated from Camellia oleifera meal by high-speed countercurrent chromatography for antibacterial application.

Natural biologically active substances have received continuous attention for the potentially beneficial health properties against chronic diseases. In this study, bacteriostatic active substance from Camellia oleifera meal, which is a major by-product of the Camellia oil processing industry, were extracted with continuous phase change extraction (CPCE) method and separated by HSCCC. Compared with traditional extraction methods, CPCE possessed higher extraction efficiency. Two main substances were separated and purified (above 90.0%). The structure of them were further identified by UV, LC–ESI–MS–MS, 1H-NMR, and 13C-NMR as flavonoids F2 kaempferol 3-O-[β-d-glucopyranosyl-(1 → 2)-α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside and J2 kaempferol 3-O-[β-d-xylopyranosyl-(1 → 2)-α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside for the first time in C. Oleifera meal. The results of antibacterial activity measurement showed that both compounds have excellent antibacterial activity. And the antibacterial stability of F2 were finally confirmed: F2 showed broad spectrum antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella enteriditis, Bacillus thuringiensis, Aspergillus niger and Rhizopus nigricans. Besides, F2 exhibited relatively high stable property even at high temperature, acid and metal ion solutions. The findings of this work suggest the possibility of employing C. oleifera meal as an attractive source of health-promoting compounds, and at the same time facilitate its high-value reuse and reduction of environmental burden.

Biotransformation of poly(cis-1,4-isoprene) in a multiphase enzymatic reactor for continuous extraction of oligo-isoprenoid molecules

Biotechnological processes for the partial degradation or transformation of poly(cis-1,4-isoprene) rubber have been investigated during recent decades with promising results. The use of the enzyme ‘latex clearing protein’ (Lcp) to transform the polymer into more hydrophilic oligo-isoprenoids results in modifications of the rubber structure and the synthesis of new material. In order to find an alternative process to recover the degradation products, a continuous extraction method using a biphasic system is described. The enzymatic activity of Lcp1VH2 was studied in the presence of ethyl acetate and pentane as extraction solvents. Oligo(cis-1,4-isoprene) molecular species were isolated from the organic phase and analyzed by Electrospray Ionization Mass Spectrometry. The enzymatic reaction process was evaluated in terms of the biotransformation yield of poly(cis-1,4-isoprene) rubber into the corresponding degradation products. Biotransformation yields of between 42–52 % were achieved depending on the enzymatic reactor design and the extraction solvent. The results also showed that the mass distribution of the oligo(cis-1,4-isoprene) depended on the organic solvent applied. A novel, simple and effective process is demonstrated for biotransformation of poly(cis-1,4-isoprene) rubber with high oligo-isoprenoid molecules recovery yields.

Evaluation of Comparative Anti-arthritic Activity of Traditionally Well Documented Medicinal Plants in Rats

The aim of our study is to evaluate comparative assessment of well documented medicinal plants. Ethanolic extract of Pongamia pinnata, Salvadora persica, Asparagus racemosus and methanolic extract of Punica granatum were prepared by continuous hot extraction method and their preliminary phytochemical screening was performed. Animals were separated into different groups and each group contains six animals. The ethanolic and methanolic extracts were administered in a dose of 200 and 400 mg/kg. Arthritis was induced by FCA in Wistar albino rats and various parameters related to arthritis i.e. paw volume, arthritic score, body weight, joint diameter were recorded. A significant increase in paw volume, arthritic score, joint diameter and decrease in body weight was observed in arthritic control rats compared to normal control. Methanolic extract of Punica granatum significantly decreased the paw volume, arthritic score, and joint diameter and increased the body weight when compared to arthritic control. All the selected medicinal plants showed significant activity in arthritic rats however, methanolic extract of Punica granatum showed highly significant activity as compared to other plants. Methanolic extract showed the presence of flavonoids, alkaloids, terpanoids, glycosides, and phenolic compounds. The anti-arthritic activity of plant may be due to presence of aforementioned phytocompoundse.

Antimicrobial activity and histopathological safety evidence of Ochradenus baccatus Delile: A medicinally important plant growing in Saudi Arabia

Background: The growing climatic condition affects plant constituents and biological activities. Ochradenus baccatus (Taily Weed) from Resedaceae family is a perennial shrub that is widely used in folk medicine in the Middle East. Aim: From the viewpoint that O. baccatus is regularly used in folk medicine, this study was designed to evaluate the antimicrobial activity and investigate the effect of O. baccatus on the biochemical and histopathological parameters of liver and kidney in experimental animals. Methods: The O. baccatus extracts were obtained by hot continuous extraction method. Agar diffusion and minimal inhibitory concentration assays were used for the antimicrobial activity. O. baccatus total extracts at doses of 100 mg/kg and 50 mg/kg were given to the first and second groups of rates, respectively, whereas the third and fourth groups received the vehicle olive oil and saline, respectively. The liver and kidney functions, as well as lipid profile and glucose levels, were measured by spectrophotometric technique on obtained blood samples. The liver and kidney tissues were evaluated for histopathological effect. Results: Ethanol and ethyl acetate extracts have similarly and potentially inhibited the bacterial micro-organisms, whereas Candida albicans was inhibited by n-hexane extract. O. baccatus total extract showed no significant effects on the kidney and liver functions (P > 0.05). However, it significantly reduced triglyceride level (P = 0.04). The histopathological investigation of liver and kidney tissues revealed no significant differences compared to control animals. Conclusion: The medicinally important plant, O. baccatus, growing in Saudi Arabia showed no significant toxic effects on the livers and kidneys. Moreover, it demonstrated a potential antimicrobial activity besides a significant reduction in serum triglycerides in rats. These findings are in consistent with other reported results suggesting no environmental effects on the safety of this plant.

Study on speciation and Distribution characteristics of Heavy Metals in soil around typical Coal Gangue in Fengfeng Mining Area

Taking the coal gangue mountain in Hebei Fengfeng mining area as the research object, 30 soil samples were collected in the east, southeast and southwest directions within 300m of the coal gangue mountain boundary, and the coal gangue stacking were used to study the heavy metal pollution of the surrounding soil. The heavy metal form of soil around coal gangue was extracted by Tessier five-step continuous extraction method, and analyzed its morphological characteristics and biological activities. The results showed that: (1) Hg and Cr were mainly retained in the soil as residual, which did little harm to the environment; Pb and Cd are mainly exist in the soil in residual and bound to iron-manganese oxide; Cu is mainly exists in the soil in residual and bound to organic matter. (2) According to the analysis of the available coefficient and migration coefficient of soil heavy metals in soil, Cd belongs to medium risk. Cu and Pb are low risk, and Cr and Hg are considered as risk-free because their available state content is lower than the detection limit.

Study on Leaching Mechanism and Safety Evaluation of Lead and Zinc Contaminated Soil

Taking the tailing pond of the Qiaokou lead-zinc mine in Hunan province as the research object, the lead-zinc-contaminated soil was leached by citric acid, and the phase characteristics of the contaminated soil before and after leaching were analyzed by SEM-EDS, combined with BCR. The continuous extraction method was used to study the occurrence of four kinds of heavy metals in contaminated soil, and then analyze the potential migration and transformation ability and migration law to evaluate the potential hazards of heavy metals to the surrounding environment, and to repair the lead and zinc tailings pond. Provide theoretical basis and technical support with governance.

Assessment of Garcinia pedunculata Roxb. Role on Biological Markers in Carbon Tetra Chloride Induced Rat Model.

Garcinia pedunculata Roxb. is an important medicinal plant of North Eastern (NE) region of India, having number of medicinal properties and used against various diseases in folk medicine. An empirical research was designed to carry out evaluation of hepatoprotective activity of the leaves of G. pedunculata with special reference to its putative protective role. Methanolic extract from the dried leaf powder of G. pedunculata Roxb. was prepared by hot continuous extraction method. The prepared extract was investigated at different dose levels for its hepatoprotective nature and further histopathological study was carried out to ascertain the degree of reversing the hepatotoxic manifestation induced by CCl4 (Carbon tetrachloride). LD50 values of the G. pedunculata Roxb. extract was found to be safe up to 2000mg. The in vivo biological studies on serum and tissues of male Wister rats at the doses of 100mg, 300mg and 600mg/kg body weight respectively was carried out taking Silymarin as standard. The methanolic extract of G. pedunculata Roxb, improved the cholesterol level along with significant improvement of SGPT (Serum Glutamate Pyruvate Transaminase), SGOT (Serum Glutamate Oxaloacetate Transaminase), ALP (Alkaline Phosphatase) and total protein in respect to Silymarin group. The test extract at the dose 600mg/kg body weight was found to significantly reverse the elevated marker enzymes i.e. SGOT, SGPT, ALP indicating its hepatoprotective role. The higher dose extracts were also found to have pronounced effect on oxidative stress parameters such as GSH and catalase on CCl4 induced rats. The histopathological studies further augmented the protective activity of G. pedunculata leaf extract thereby endorsing the traditional usage of the plant.

Distribution and Bioavability of Phosphorus in Surface Sediments in Megalopolis: A Case Study of Chengdu

A total of 33 surface sediments were collected from rivers in Chengdu. The content of phosphorus species was measured with the chemical continuous extraction method (SMT) and in situ monitoring techniques (DGT). Multivariate statistical analysis was used to analyze the spatial distribution of phosphorus species in sediments. The release flux of DGT-P in sediments and their pore water was calculated in this study. It is helpful to understand the influence of sediment endogenous pollution and human activities on the environment. The results show that the phosphorus species have a spatial variability. The average content of TP in the surface sediments is 1132.41 mg·kg-1, which is higher than the background value of 365.00 mg·kg-1 in Chengdu. The Ca-P is the most dominant species, accounting for 70.58% of the TP on average. The study area is divided into three groups based on spatial clustering. Groups 1 and 3 show large differences of phosphorus morphological structures, while Group 2 is small. The contents of phosphorus in the surface sediment of Groups 1 and 3 are generally higher than those of Group 2. The DGT-P concentration has a good correlation with the soluble DTP concentration, bioavailable Fe/Al-P, and OP concentration, respectively. The DGT technology can be used as a fast, in situ, reliable method for measurements of the bioavailable content of sediments. The higher release fluxes of bioavailable phosphorus are N8, W11, and N2, which are 20.05, 17.13, and 14.79 mg·(m2·d)-1 respectively. The available phosphorus release capacity is closely related to human activities.

Heartrate-Dependent Heartwave Biometric Identification With Thresholding-Based GMM–HMM Methodology

This paper presents an adaptive heartrate-dependent heartwave-signal-based biometric identification. A reliable and continuous heartwave extraction method featuring the hybridized discrete waveform transform method with heartrate adaptive QT and PR intervals to perform comprehensive heartwave features extractions on more than 35 000 heartwave signal. The size of training data was determined and the hybridized Gaussian-mixture-model-hidden-Markov-model classification method was used in the classification. Dynamic thresholding criterial incorporating user-specific scores and heartrate were adopted. The identification process using dynamic thresholding criterial achieved a remarkable receiver operating characteristic of 0.89 in true positive rate and an equal error rate of 0.11.

Antibacterial property of Azadirachta indica, Ocimum sanctum, and Vitex negundo against oral microbes.

Context:Plant extracts are used in folklore medicine from time immemorial to treat different oral diseases. Chemical constituents extracted from these natural resources are gifted with huge opportunities.Aim:The aim of this study is to assess the antibacterial property of Azadirachta indica (Neem), Ocimum sanctum (Tulsi), and Vitex negundo (Pochotia) against oral microorganisms.Materials and Methods:Plant extract was prepared with hot continuous extraction method by the Soxhlet Apparatus. Microorganisms isolated from the oral cavity and identified by Vitek-2. Bacterial inoculums poured and spread into Mueller Hinton plates. Plant extract was poured into prepared wells taking ciprofloxacillin as the positive control and dimethyl sulfoxide as the negative control. The experiment was performed in duplicates with two different concentrations of the extract and mean value of inhibition zone was calculated.Statistical Analysis:Paired t-test, analysis of variance, and regression analysis.Results:Isolated microorganisms were Klebsiella oxytoca, Kochuria kristinae, Acinetobacter boumani, Sphingomonas paucimobilis, Pseudomonas fluorescens, Streptococcus gordonii, Enterococcus faecalis, and Bacillus subtilis. Higher zone of inhibition was observed against E. faecalis by V. negundo followed by A. indica. Among the aqueous and acetone group, in the aqueous group, the regression models of K. kristinae and B. subtilis have been found to be statistically significant (P= < 0.05), whereas, in the acetone group, the regression model of B. subtilis has been found to be statistically significant (P = < 0.05).Conclusion:All the three plants showed antibacterial potency against the isolated organisms. Acetone group showed better efficacy than the aqueous extract group.

WOUND HEALING POTENTIAL OF METHANOLIC EXTRACT OF FLOWERS OF BUTEA MONOSPERMA LINN. IN DIABETIC ANIMALS

The main of our study is to evaluate the Wound Healing Potential of Methanolic Extract of Flowers of Butea monosperma Linn. in Diabetic Animals. Methanolic extract was prepared by continuous hot extraction method by soxhlet apparatus. Preliminary phytochemical screening showed the presence of flavonoids, phenolic compounds and some glycosides. Diabetes was induced by single injection of Alloxan monohydrate in Wistar albino rats and their blood glucose levels were measured. Excision wound model was used for creation of wound in diabetic animals and methanolic extract was administered in diabetic animals to observe its effect. Methanolic extract significantly lowered the blood glucose level and highly significantly showed wound contraction in diabetic animals. The preliminary phytochemical analysis of the Butea monosperma flower extract showed the presence of tannins, flavonoids and triterpenoids. As per previous literature survey, flavonoids are responsible for anti-diabetic and wound healing activity. So this wound healing effect of Butea monosperma may be due to presence of flavonoids in plant. Hence present research supports traditional claims of the plant in wound healing.&#x0D; Keywords: Butea monosperma, Diabetic animals, Alloxan monohydrate, Methanolic Extract, Wound Area

Chemical state analysis of lead and zinc in soil of xitieshan mining area in the northern margin of qaidam basin

The chemical state of Pb, Zn can explain the migration law, and evaluate the threat of heavy metal pollution. The three-step continuous extraction method of BCR was adopted to divide the chemical forms of Pb and Zn in the soil into the acid-exchanged, oxidizable, reducible, and residual states. It was found that the coefficient of variation and the degree of dispersion of exchangeable, oxidizable, and reducible states were large, the results showed that all the chemical forms of Pb, Zn in soil were greatly affected by external sources except the residual state. Most of the Pb chemical forms in the mining area exist in the reducible and residual state, Zn is mainly in the oxidizable state and the reducible state; Pb is mainly in the oxidizable state, and most of the Zn is in the residual state in reference area. The oxidizable state and the reducible state are easily released when the redox potential changes, and the residual Zn may be released under severe environmental conditions, it is shown that the migration of silicate, primary and secondary minerals is difficult after natural geological weathering, etc. The contents of Pb, Zn in all forms were positively correlated with Ph of soil, positively correlated with sand content, and negatively correlated with clay content. The reasons were related to the enrichment of Pb, Zn mineralization elements in the mining area. These chemical states can indicate the chemical effects and accumulation patterns of Pb, Zn in soil.

Migration and transformation of different phosphorus forms in rainfall runoff in bioretention system.

Artificial bioretention system consisting of Ophiopogon japonicus infiltration medium was used to simulate an infiltration experiment of rainfall runoff. Continuous extraction method was used to detect contents of inorganic phosphorus (P) under exchangeable state (Ex-P) and aluminium phosphate (Al-P) and iron phosphate (Fe-P) at different depths (0, 5, 15 and 35cm) of soil infiltration medium in bioretention system. Effluent total P (TP) concentration of the system was also monitored. Results indicated that the adsorption of inorganic P, Al-P and Fe-P by soil infiltration medium was implemented layer by layer from top to bottom and gradually weakened. Moreover, Ex-P was gradually transformed into Al-P and Fe-P, whereas Al-P was gradually transformed into Fe-P; thus, Ex-P content reduced layer by layer, whereas Al-P and Fe-P gradually accumulated. The TP removal rate in runoff rainwater by the system was more than 90%, where the TP that was not used by plants was under dynamic equilibrium in water-soil-root system/biological system.