Phytochemical profiling and biological activity of Plectranthus amboinicus (Lour.) mediated by various solvent extracts against Aedes aegypti larvae and toxicity evaluation

Objective: To analyze the phytochemical compounds and to investigate the bio-toxic efficacy of various solvent extracts of Plectranthus amboinicus against mosquito larvae activity and lethality on non-targeting organisms. Methods: The methanol, ethyl acetate, hexane, and aqueous extracts of Plectranthus amboinicus were subjected to analyze the mosquitocidal activity against the dengue vector, Aedes aegypti and toxicity assays on zebra fish and brine shrimp. Three replications were performed, and negative control was also maintained. Amongst, ethyl acetate extract of Plectranthus amboinicus was chosen for the determination of bio-active compounds. Results: The mosquitocidal assays of methanol and ethyl acetate extracts of Plectranthus amboinicus showed the maximal activity with minimal concentration against the 4th instar mosquito-larvae of Aedes aegypti through the following lethal concentration (LC50 and LC90) values: 53.36 & 92.51 μg/mL and 13.64 & 86.09 μg/mL, respectively. In addition, the plant extracts showed no toxicity on zebra fish embryo and brine shrimp assays. The gas-chromatography analysis of the ethyl acetate extract of Plectranthus amboinicus revealed the presence of seven different compounds. Among them, PAEA-fraction 60 contained a major active bioactive compound, hexadecanoic acid, methyl ester (270.0). Conclusions: Plectranthus amboinicus possesses mosquitocidal properties and could be used as a potential alternative source for preparing the mosquitocidal agents.

Research progress on percolation extraction process of traditional Chinese medicines / 中国中药杂志

Percolation extraction is a conventional extraction method used in the processing of traditional Chinese medicines. After medicinal material powder is placed in a percolation tank, the extraction solvent is continuously added, and percolation extract is collected simultaneously. The percolation equipment is simple. The percolation operation is easy. It is applicable to a wide range of medicinal materials. Components that are unstable under thermal conditions can be effectively extracted. However, there are also disadvantages, such as high solvent consumption, long extraction time, and high energy consumption in subsequent concentration processes. This article mainly reviews the research progress on the common equipment types, affecting factors, parameter optimization methods, and process monitoring. According to analysis on literatures, solvent composition, impregnation time, percolation speed, and solvent consumption are considered as the important factors of percolation processes. At present, near-infrared spectroscopy is widely used in the monitoring of percolation process, and partial least square is a commonly used quantitative modeling method. According to the concept of "Quality by Design", in-depth investigation of the percolation process mechanism and development of process control methods are future development trends. Therefore, process modeling, process optimization and process monitoring shall be improved. The mechanism models and the empirical models of column chromatography can be used as references to construct the percolation process models. The effect of the quality changes of medicinal materials shall be taken into account when optimizing the percolation process parameters. More simple and easy methods shall be developed to monitor the percolation process status and key properties of percolation extracts.

Phytochemical profiling and biological activity of Plectranthus amboinicus (Lour.) mediated by various solvent extracts against Aedes aegypti larvae and toxicity evaluation

Objective: To analyze the phytochemical compounds and to investigate the bio-toxic efficacy of various solvent extracts of Plectranthus amboinicus against mosquito larvae activity and lethality on non-targeting organisms. Methods: The methanol, ethyl acetate, hexane, and aqueous extracts of Plectranthus amboinicus were subjected to analyze the mosquitocidal activity against the dengue vector, Aedes aegypti and toxicity assays on zebra fish and brine shrimp. Three replications were performed, and negative control was also maintained. Amongst, ethyl acetate extract of Plectranthus amboinicus was chosen for the determination of bio-active compounds. Results: The mosquitocidal assays of methanol and ethyl acetate extracts of Plectranthus amboinicus showed the maximal activity with minimal concentration against the 4th instar mosquito-larvae of Aedes aegypti through the following lethal concentration (LC50 and LC90) values: 53.36 & 92.51 μg/mL and 13.64 & 86.09 μg/mL, respectively. In addition, the plant extracts showed no toxicity on zebra fish embryo and brine shrimp assays. The gas-chromatography analysis of the ethyl acetate extract of Plectranthus amboinicus revealed the presence of seven different compounds. Among them, PAEA-fraction 60 contained a major active bioactive compound, hexadecanoic acid, methyl ester (270.0). Conclusions: Plectranthus amboinicus possesses mosquitocidal properties and could be used as a potential alternative source for preparing the mosquitocidal agents.

GC–MS analysis of bioactive compounds present in different extracts of an endemic plant Broussonetia luzonica (Blanco) (Moraceae) leaves

Objective To investigate and characterize the chemical composition of the different crude extracts from the leaves of Broussonetia luzonica (Blanco) (Moraceae) (B. luzonica), an endemic plant in the Philippines. Methods The air dried leaves were powdered and subjected to selective sequential extraction using solvents of increasing polarity through percolation, namely, n-hexane, ethyl acetate and methanol to obtain three different extracts. Then, each of the extracts was further subjected to gas chromatography–mass spectrometry. Results Qualitative determination of the different biologically active compounds from crude extracts of B. luzonica using gas chromatography–mass spectrometry revealed different types of high and low molecular weight chemical entities with varying quantities present in each of the extracts. These chemical compounds are considered biologically and pharmacologically important. Furthermore, the three different extracts possess unique physicochemical characteristics which may be attributed to the compounds naturally present in significant quantities in the leaves of B. luzonica. Conclusions The three extracts possess major bioactive compounds that were identified and characterized spectroscopically. Thus, identification of different biologically active compounds in the extracts of B. luzonica leaves warrants further biological and pharmacological studies.

GC-MS analysis of bioactive compounds present in different extracts of an endemic plant Broussonetia luzonica (Blanco) (Moraceae) leaves

Objective: To investigate and characterize the chemical composition of the different crude extracts from the leaves of Broussonetia luzonica (Blanco) (Moraceae) (B. luzonica), an endemic plant in the Philippines. Methods: The air dried leaves were powdered and subjected to selective sequential extraction using solvents of increasing polarity through percolation, namely, n-hexane, ethyl acetate and methanol to obtain three different extracts. Then, each of the extracts was further subjected to gas chromatography–mass spectrometry. Results: Qualitative determination of the different biologically active compounds from crude extracts of B. luzonica using gas chromatography–mass spectrometry revealed different types of high and low molecular weight chemical entities with varying quantities present in each of the extracts. These chemical compounds are considered biologically and pharmacologically important. Furthermore, the three different extracts possess unique physicochemical characteristics which may be attributed to the compounds naturally present in significant quantities in the leaves of B. luzonica. Conclusions: The three extracts possess major bioactive compounds that were identified and characterized spectroscopically. Thus, identification of different biologically active compounds in the extracts of B. luzonica leaves warrants further biological and phar-macological studies.

Optimization of percolation extraction technology for Qixue Shuangbu Tinctura by Box-Behnken response surface methodology / 中草药

Objective: To optimize the percolation extraction technology for Qixue Shuangbu Tinctura by response surface methodology (RSM). Methods: The single factor experiment combined with Box-Behnken design was used to optimize the extracting technology, with six major characteristic components (ginsenoside Rb1, calycosin 7-O-β-D-glucopyranoside, ferulic acid, stilbene glucoside, paeoniflorin, hesperidin) and extract of Qixue Shuangbu Tinctura as indexes, in order to detect three factors, including the alcohol volume fraction, the dosage of ethanol, and the percolate speed, and optimize the extraction process of Qixue Shuangbu Tinctura. Results: Optimum percolation process was added 10 times of the amount of 48% ethanol with percolation speed of 1.4 mL/min. Conclusion: This optimized extraction technology of Qixue Shuangbu Tinctura is reasonable, stable, and feasible, and with high accuracy, which could be extended to the applications of large-scale production.

Efeito da calagem na lixiviação de imazethapyr e imazapyr em solo de cultivo de arroz irrigado / Effect of liming on imazethapyr and imazapyr leaching in rice paddy soil

Os herbicidas do grupo das imidazolinonas são amplamente utilizados no cultivo de arroz irrigado para o controle das principais plantas daninhas. Esses herbicidas comportam-se como ácidos ou bases fracas, dependendo do pH, podendo, dessa forma, influenciar na sua lixiviação. O objetivo deste estudo foi avaliar o efeito da elevação do pH, através da calagem, na lixiviação de imazethapyr e imazapyr em solo de cultivo de arroz irrigado. Foram coletadas amostras indeformadas de solo com pH natural próximo a 4,8 em uma lavoura de arroz irrigado sem histórico de aplicação de imidazolinonas. As colunas de solo foram coletadas utilizando-se um extrator e constituíram-se nas unidades experimentais da primeira fase do experimento. O experimento foi conduzido em casa de vegetação, arranjado em esquema fatorial, sendo o fator A constituído por solo com pH natural e solo com calagem. O fator B foi constituído pelos herbicidas imazethapyr e imazapyr (todos a 100g i.a. ha-1), aplicados sobre a superfície das colunas de solo. O fator C foi constituído das profundidades de amostragem (5 em 5cm). Os resultados mostram que a alteração do pH influencia na lixiviação dos herbicidas testados, quando aplicados em solo de cultivo de arroz irrigado. O solo calcareado apresenta maior lixiviação dos herbicidas imazapyr e imazethapyr.

Imidazolinone herbicides are widely used in rice for the control of major weeds. These herbicides behave as weak acids or bases, depending on the pH which may affect leaching. The objective of this study was to evaluate the effect of liming on imazethapyr and imazapyr leaching. Undisturbed soil samples (pH 4.8) were collected in a rice paddy field without history imidazolinone application. The soil columns, that constituted the experiment units, were collected using a soil extractor constituting. The experiment was conducted in a greenhouse, arranged in a factorial design, begin the factor A included of soil with natural pH and limed soil. Factor B was included the herbicides imazethapyr and imazapyr (all at 100g a.i. ha-1) applied to the surface of the soil columns. Factor C included of sampling depths at the end of the experiment to evaluate leaching (5 by 5cm). The results showed that enhanced pH cause by liming affect herbicide leaching in rice paddy soil. Soil liming enhance imazethapyr and imazapic leaching.

Group behaviour in physical, chemical and biological systems.

Groups exhibit properties that either are not perceived to exist, or perhaps cannot exist, at the individual level. Such ‘emergent’ properties depend on how individuals interact, both among themselves and with their surroundings. The world of everyday objects consists of material entities. These are, ultimately, groups of elementary particles that organize themselves into atoms and molecules, occupy space, and so on. It turns out that an explanation of even the most commonplace features of this world requires relativistic quantum field theory and the fact that Planck’s constant is discrete, not zero. Groups of molecules in solution, in particular polymers (‘sols’), can form viscous clusters that behave like elastic solids (‘gels’). Sol-gel transitions are examples of cooperative phenomena. Their occurrence is explained by modelling the statistics of inter-unit interactions: the likelihood of either state varies sharply as a critical parameter crosses a threshold value. Group behaviour among cells or organisms is often heritable and therefore can evolve. This permits an additional, typically biological, explanation for it in terms of reproductive advantage, whether of the individual or of the group. There is no general agreement on the appropriate explanatory framework for understanding group-level phenomena in biology.

An on-line near-infrared spectroscopy approach for content determination in the percolation process of compound Kushen injection / 中国药学杂志

OBJECTIVE: To develop an on-line analysis method based on near infrared spectroscopy (NIRS) for monitoring the percolation process of compound Kushen injection traditional Chinese medicines. METHODS: Samples and correlative spectra were collected with online equipment in percolation process. The contents of total alkaloids and total solids measured with standard methods were used as reference values. Multivariate calibration models based on partial least squares (PLS) algorithm were developed to correlate the spectra and the reference values. RESULTS: The correlation coefficients of the calibration models for total alkaloids and total solids were 0.9979 and 0.9960 with root mean square errors (RMSECs) of 0.0721 g · L-1 and 0.0811%, respectively. External validation samples collected on-line were used to evaluate the quantitative models. The correlation coefficients between the predicted value and the reference value were 0.9915 and 0.9990 with root mean square errors of prediction (RMSEPs) of 0.1950 g· L-1 and 0.0681%, respectively. CONCLUSION: The presented method is rapid, accurate and reliable, which can be used for monitoring the percolation process of compound Kushen injection.

Relação da granulometria do solo e morfologia do saprolito com a infiltração de água em Neossolos Regolíticos do rebordo do Planalto do Rio Grande do Sul / Relationship between soil size particle distribution and saprolite morphology with water infiltration in Neossolos Regolíticos (Regossols) in the Rio Grande do Sul Plateau edge

Os Neossolos Regolíticos apresentam baixo potencial de uso devido a sua pequena profundidade efetiva, à presença de pedregosidade/rochosidade, ao contato lítico próximo à superfície e à ocorrência frequente em terrenos declivosos. Análises mais detalhadas são necessárias para a melhor interpretação desses solos, visto que a filtragem da água de percolação, retenção de solutos e fluídos e sua possível transformação são de interesse ambiental. Nesse sentido, este estudo gerou informações sobre a infiltração de água em cinco áreas de Neossolos Regolíticos, na região do Rebordo do Planalto do Rio Grande do Sul. Para cada área foram descritos e analisados três perfis, sendo a infiltração de água determinada pelo método dos duplos anéis concêntricos. Mesmo com idêntica classificação taxonômica até o quarto nível categórico, os Neossolos apresentaram variações no seu comportamento hídrico, inclusive quando comparados entre os perfis do mesmo ponto de coleta. Os dados sugerem que a infiltração, nesses Neossolos, é influenciada pela configuração de fraturas do saprolito, granulometria, condições de relevo e uso do solo.

Neossolos Regolíticos (Regosols) are fragile from a natural resource perspective because of their small depth, stones and/or rocks presence, near surface lithic contact, fractures in saprolite and frequent occurrence in steep slopes. These soils requires more specific analysis for a better interpretation of their capacity to filtrate water, retain and transform solute and fluids, contributing to the maintenance of the water quality that reaches the groundwater. In that sense, this study generates information on water infiltration in five areas from the the Rio Grande do Sul plateau edge. Three profiles were described and analyzed for each Regosol and the water infiltration was performed whit the double rings method. Even showing the same taxonomic classification, the Regosols showed hydraulic variation behavior, even though when compared among the profiles from the same location. The data suggest that the water infiltration in the Regosols is affected by the saprolite fracture configurations, granulometry, relief conditions and soil use.

Lixiviação do imazethapyr em solo de várzea sob dois sistemas de manejo / Imazethapyr leaching in rice paddy soil under two tillage systems

O imazethapyr está sendo amplamente utilizado no Rio Grande do Sul desde o desenvolvimento da Tecnologia Clearfield® (CL) em arroz, em uma mistura formulada de imazethapyr + imazapic (75 + 25g L-1). No entanto, com o uso dessa tecnologia, surgiu o problema da persistência do herbicida no solo, afetando cultivos não tolerantes em sucessão com diferentes intensidades. A fitointoxicação está relacionada, dentre vários fatores, à localização do herbicida no perfil do solo. O presente trabalho teve por objetivo determinar o posicionamento do imazethapyr em profundidade, no perfil de um solo de várzea cultivado com arroz, frente a dois tipos de manejo. Foram coletadas amostras de solos, em diferentes profundidades (0-5, 5-10, 10-15 e 15-20cm), do solo de várzea sob dois sistemas de manejo: plantio convencional (PC) e plantio direto (PD), em uma área onde havia sido utilizado arroz CL por dois anos e no terceiro ano, arroz não tolerante. A concentração do herbicida no solo foi analisada por HPLC-DAD. Há maior concentração de imazethapyr na superfície do solo (0-5cm), no sistema convencional, quando comparado com o sistema de plantio direto, e o herbicida lixiviou até 20cm nos dois sistemas. No PC, ocorreu uma distribuição uniforme do imazethapyr nos primeiros 15cm de solo, enquanto que, no PD, constatou-se acúmulo de imazethapyr nas camadas de 5-10 e 10-15cm.

Imazethapyr has been widely used in Rio Grande do Sul since the development of Clearfield TechnologyTM(CL) on rice, in a formulated mixture of imazethapyr + imazapic (75 + 25g L-1). However, the use of such technology raised the problem of herbicide carryover, which might affect non-tolerant crops in rotation with different intensities. The plant injury is related, among other factors, with the herbicide position in the soil profile. The present work had the objective of determining the depth positioning of imazethapyr on a lowland soil cultivated with rice in two soil tillage system: conventional system (CS) and no till system (NT), in an area where CL rice had been cultivated for two years followed by non tolerant rice in the third year. Herbicide concentration in soil samples was analyzed by HPLC-DAD. There is a higher concentration of imazethapyr in the topsoil (0-5cm) on the CS, when compared to the NT, while it leached until 20cm in both systems. In the CS, imazethapyr were uniformly distributed in the first 15 cm of soil, whereas in NT, imazethapyr were accumulated in 5-10 and 10-15cm layers.

Study on Percolation Extract Process of Quyou Tincture / 中国中医药信息杂志

Objective To optimize the extract technology of Quyou Tincture with orthogonal design.Methods With the determination of peoniflorin and paeonol and the extraction rates as indexes,the extract conditions of Quyou Tincture was optimized by orthogonal design.Results The optimal preparation process of alcohol was as follows:adding 6 times alcohol(75%),immerse 24 hours and percolate with 1 mL/min.Conclusion The optimum extracting condition was simple,with a high extraction rate and low cost.

Study on Percolation Processes of Rhizoma Pinelliae(Processed with Ginger) / 中成药

Objective: To study the optimum extraction conditions of alkaloid of Rhizoma pinelliae processecd with ginger.Methods:The alkaloid content was used as a marker.The percolation process of Rhizoma Pinellia(processed with ginger) was studied by orthogonal design with 3 factors and 3 levels(L 9(3 4)) .Results:The alcohol concentration was remarkable factor in the test.Conclusion:Considering the demand of manufacture,the best extraction condition is A 3B 1C 1。

Study on Selection of Preparation Procedure of Buqiyangxuecuiru Oral Liquid / 中成药

Objective: To select the optimum extraction procedure for Buqiyangxuecuiru Oral Liquid. Methods: The water extraction, water extraction and alcohol precipitation, and alcohol percolation procedures were designed. Taking contents of ferulic acid and astragalus saponins I, and the lactation quantity of normal lactation mice as markers, the rational preparation procedure was selected. Results: The oral liquid prepared by the procedure of alcohol percolation. Both ferulic acid and astragalus saponins I contents in this preparation were the highest, and it could remarkably increase the lactation quantity of normal mice. Conclusion: The alcohol percolation procedure was the optimum extraction procedure for Buqiyangxuecuira Oral Liquid.