exhaustive extraction
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2021 ◽  
Vol 7 (3) ◽  
pp. 11-23
Author(s):  
V. Platonov ◽  
B. Valentinov ◽  
G. Suhih ◽  
M. Volchaeva ◽  
V. Dunaev ◽  
...  

The purpose of the study is to show the expediency of sequentially extracting herbal medicinal raw mate-rials with solvents in order of increasing their polarity, to reveal the nature of the distribution of both different groups of compounds and individual ones in the organic matter of thyme (thyme creeping). Re-sults and their discussion. The results of comparative characterization of the chemical composition and direction of pharmacological action of n-hexane, choroform and ethanol extracts of sequential exhaustive extraction of thyme herb (creeping thyme) obtained using chromatography-mass spectrometry, mass spectra and structural formulas of individual compounds, which were identified in 162 (n-hexane), 101 (chloroform) and 150 (ethanol) extracts. The influence of the nature of the solvent on both the yield of extracts and the structural and group composition of the latter, the features of the structural organization of the extracted compounds have been established, the specificity of the direction of the pharmacologi-cal action of each of the extracts, which made it possible to justify the expediency of successive exhaustive extraction of the initial medicinal raw materials with solvents in ascending order of their polarity.


Author(s):  
Ushie OA ◽  
Iyen SI ◽  
Longbab BD ◽  
Ama SO ◽  
Azuaga TI

The aim of this work was to carry out the phytochemical screening and antimicrobial activities of Haematostaphis barteri. The method of cold maceration was used in the extraction by serial exhaustive extraction method which involves successive extraction with solvents of increasing polarity from a non-polar (hexane) to a more polar solvent (methanol) to ensure that a wide polarity range of compound could be extracted. The results showed that flavonoids, terpenes, terpenes, tannins, and saponins are present in all the leaf extracts. The result of the antimicrobial activity obtained from the extracts of the leaf of Haematostaphis barteri revealed that all the crude extracts of the leaf inhibited or exhibited antibacterial activity against Salmonella paratyphi, Staphylococcus aureus, Escherichia coli, and Penicillium spp. All the extracts did demonstrate antimicrobial activity against Aspergillus niger. The plant H. barteri is commonly used traditionally for the treatment of diarrhoea, wound, headache, malaria, dysentery and fevers. The overall results confirm the significance of the use of the plant in traditional medicinal treatment of diarrhea, wound, headache, malaria, dysentery and fevers, in line with reported claims.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Vincent Ngouana ◽  
Elisabeth Zeuko’o Menkem ◽  
Diane Yimta Youmbi ◽  
Lorette Victorine Yimgang ◽  
Rufin Marie Kouipou Toghueo ◽  
...  

Microbial infections are increasing worldwide, and the widespread emergence of antibiotic-resistant pathogens poses a severe threat to public health. Medicinal plants are well-known sources of bioactive ingredients. This study was designed to determine the antimicrobial and antioxidant activities of extracts from Platycerium stemaria. The serial exhaustive extraction method using a solvent of increasing polarity from nonpolar (hexane) to polar (water) was designed to prepare crude extracts; liquid-liquid partition was used to fractionate of active extracts. The extracts and fractions were screened for antimicrobial activity on bacteria and yeasts using the microdilution method. The antioxidant activity was done using DPPH and FRAP assays. Out of the sixteen extracts screened, four (PsHex, PsH2O(H), PsMeOH(EA), and PsMeOH) exhibited potency with minimal inhibitory concentration (MIC) values ranging from 31.25 to 500 μg/mL. Out of the four extracts, two, including PsMeOH and PsMeOH(EA), exhibited DPPH radical scavenging activity with the antiradical power of 8.94 × 10 − 5 and 47.96 × 10 − 5 , respectively, and ferric reducing antioxidant power values ranging from 0.34 to 61.53 μg equivalent Vit C/g of extract. The phytochemical screening of the promising crude extracts revealed flavonoids, glycosides, phenols, tannins, terpenoids, saponins, and anthraquinones. This study reports the antimicrobial and antioxidant activities of P. stemaria for the first time. The results showed that the serial exhaustive extraction approach used in this study allowed capturing the antimicrobial and antioxidant metabolites beyond the single extraction, indicating the need for a rigorous choice of an appropriate solvent and method for extracting P. stemaria. Further investigation is needed to characterize the active ingredients present in the promising extracts.


Author(s):  
Johant Lakey-Beitia ◽  
Velmarini Vasquez ◽  
Randy Mojica-Flores ◽  
Arelys L. Fuentes C. ◽  
Enrique Murillo ◽  
...  

Background: Red mamey fruit known as P. sapota, comes from trees found in Mesoamerica and Asia. This fruit is considered a nutraceutical food due to it’s a food and has multiple beneficial health including anti-amyloidogenic activity and potential anti-tumorigenic property. Red mamey fruit contain a variety of carotenoids including novel ketocarotenoids such as sapotexanthin and cryptocapsin. A ketocarotenoid is a chemical compound with a carbonyl group present in the β-ring or in the double bond chain of a carotenoid. In red mamey, the 3'-deoxy-k-end group in sapotexanthin has proved to be an important pro-vitamin A source, which is essential for maintaining a healthy vision and cognitive processes. Objective: Summarize the chemistry and biological activity of the studied carotenoids present in this fruit until now. Method: An exhaustive extraction is the most usual methodology to isolate and thoroughly characterize the carotenoids present in this fruit. High performance liquid chromatography is used to determine the profile of total carotenoid and its purity. Atmospheric pressure chemical ionization is used to determine the molecular weight of carotenoid. Nuclear magnetic resonance is used to determine the structure of carotenoids. Result: For each 100 g of fresh weight, 0.12 mg of total carotenoid from this fruit can be obtained. Out of the more than 47 reported carotenoids in red mamey, only 34 have a detailed characterization. Conclusion: it is important to continue studying the chemical composition and biological activity of this unique tropical fruit with commercial and nutritional value.


2021 ◽  
Vol 10 (2) ◽  
pp. e9310212312
Author(s):  
Lara Vinha Faria ◽  
Heliton Patrick Cordovil Brígido ◽  
Alexandre Augusto Bentaberry-Rosa ◽  
Juliana Correa-Barbosa ◽  
João Victor Silva-Silva ◽  
...  

This study aimed to evaluate the anti-leishmania activity of extracts and fractions from stem and leaf of Montrichardia linifera against Leishmania amazonensis. The stem (EES) and leaf (EEL) extracts were obtained by maceration of powders with 96º GL alcohol. The extracts were subjected to exhaustive extraction using a reflux system and solvents of increasing polarity, obtaining 4 fractions for each extract: hexane, dichloromethane, ethyl acetate and methanol. The extracts and fractions were submitted to a phytochemical prospecting study. The antipromastigote activity and cytotoxicity in macrophages (J774) were performed using the cell viability test (MTT). In the extract and fractions of the stem, alkaloids, steroids, terpenes, flavonic heterosides, tannins, polyphenols and saponins were detected. In the extract and fractions of the leaves, coumarins, steroids, terpenes, flavonic heterosides, tannins, polyphenols and saponins were detected. In the anti-leishmania evaluation, the hexane fraction of the leaf (HFL) showed promising activity (IC50=38.56 µg/mL), and the hexane fraction of the stem (HFS) showed moderate activity (CI50=179.3 µg/mL), the extracts and the other fractions were inactive (IC50>200 µg/mL). In the cytotoxicity test, EES and HFS were cytotoxic (CC50 54.82 µg/mL and 26.95 µg/mL, respectively). EEF and HFL showed moderate cytotoxicity (CC50 of 162.7 µg/mL and 347.1 µg/mL). As for the selectivity index, the HFL showed high selectivity (SI=90). In summary, fractionation contributed to increase anti-leishmania activity and the selectivity of HFS, such activity may be related to steroids or terpenes.


2021 ◽  
Vol 22 (1) ◽  
pp. 125-154
Author(s):  
Marieke Meelen ◽  
David Willis

This article introduces the working methods of the Parsed Historical Corpus of the Welsh Language (PARSHCWL). The corpus is designed to provide researchers with a tool for automatic exhaustive extraction of instances of grammatical structures from Middle and Modern Welsh texts in a way comparable to similar tools that already exist for various European languages. The major features of the corpus are outlined, along with the overall architecture of the workflow needed for a team of researchers to produce it. In this paper, the two first stages of the process, namely pre-processing of texts and automated part-of-speech (POS) tagging are discussed in some detail, focusing in particular on major issues involved in defining word boundaries and in defining a robust and useful tagset.


2020 ◽  
pp. 54-59
Author(s):  
A. D. Borovskaya ◽  
N. E. Mashchenko ◽  
R. A. Ivanova ◽  
A. V. Gumanyuk

Relevance. Increasing the resistance of vegetable plants to unfavorable growing conditions with the use of growth regulators that actively affect the seed quality, increase the survival rate of seedlings, stimulate the setting, formation and maturation of the crop is a significant reserve for increasing productivity with the already achieved level of intensification of their production.Material and methods. The effect of verbascosides obtained by exhaustive extraction with 60% aqueous ethyl alcohol from the aboveground part of Verbascum densiflorum Bertol. (Scrophulariaceae) was studied on the germination, growth, development and yield of tomatoes, cucumbers, onions and white cabbage. Before sowing, the seeds were soaked in an aqueous solution of verbascosides for 15-20 minutes, followed by drying to flowability at the rate of 0.5-0.8 liters of solution per 1 kg of seeds.Results. It is shown, that possessing phytoregulatory activity and influencing the metabolic and synthetic reactions of plants, these compounds, applied exogenously, stimulate the seed germination energy and total germination of vegetable crops, provide simultaneous appearance of seedlings and optimal plant density, accelerate the growth dynamics of plants assimilation surface and fruit mass. Reducing the consequences of stresses arising in the process of plant growth and development, they thereby contribute to increasing plant resistance, productivity and improving the commercial quality of the products. The ability of these compounds to improve the production process of vegetable crops, depending on the type and variety of vegetables was established. Their highest stimulating effect was determined on cabbage variants, where the yield exceeded the control by 34.3%. The performed studies and obtained results allow to recommend the pre-sowing seed treatment with a 0.01% solution of biological active substances from Verbascum densiflorum Bertol. as an element in technology of growing vegetable.


2020 ◽  
Vol 7 (3) ◽  
pp. 23-26
Author(s):  
Achimugu Dickson Musa ◽  
Sandra Tombiah Dorgu ◽  
Cyril Ogbiko ◽  
Jeremiah Ikko ◽  
Muhammad Hausa Shuaib ◽  
...  

This study was designed to explore new antibacterial agent(s) from the defatted methanol and water extracts of Ficus capensis. The extracts were obtained using various solvents, namely, cyclohexane, dichloromethane, methanol, and water by serial exhaustive extraction, after which both extracts were challenged with pure clinical isolates of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Acinetobacter baumannii, and Burkolderia cepacia viz-a-viz standard antibiotics of chloramphenicol, gentamicin, and amoxicillin at 25 μg/ml, 50 μg/ml, and 100 μg/ml concentrations using spectrophotometric method. Using the zone of inhibition as an inhibitory parameter, both extracts of F. capensis showed promising antimicrobial activity in a concentration-dependent manner comparable to the standard antibiotics for all tested microorganisms. This research holds promise for the exploration of various potentially active secondary metabolites which would help in developing pharmaceuticals, especially antibacterial drugs, for combating common microbial infections. This validates the use of the plant leaves in the treatment of broad-spectrum microbial infections in ethnomedicine.


2020 ◽  
Vol 6 (1) ◽  
pp. 53-56
Author(s):  
V. Platonov ◽  
Aleksandr Hadarcev ◽  
G. Suhih ◽  
V. Frankevich ◽  
M. Volochaeva ◽  
...  

This report presents the results of chromatography-mass spectrometry of a chloroform extract obtained after preliminary sequential exhaustive extraction of the bark of ordinary oak (petiole) n-hexane and toluene. The purpose of the study is to significantly expand the range of compounds that determine the composition of the organic matter of the bark of ordinary oak (petiole). Materials and research methods. The dried raw material is ground to a powder in a porcelain laboratory mill, which is then subjected to exhaustive sequential extraction with n-hexane and toluene at boiling points. Then, the solid residue was dried to constant weight in a vacuum oven, and then extraction was carried out with chloroform at its boiling point. Extraction with chloroform was completed when the refractive index was reached equal to its initial value, after which chloroform was distilled off in a vacuum rotary evaporator to obtain a dark brown oily residue. Thus, we can conclude that the pharmacological effect of the chloroform extract of ordinary oak bark (petiolate) will be determined by the presence of significant amounts of sterols, hydrocarbons, which are dominated by arenes, alkenes and cycloalkanes, esters formed mainly by dicarboxylic acid (Oxalic acid).


2020 ◽  
Vol 5 (1) ◽  
pp. 39-50
Author(s):  
Gashaw Nigussie

Rumex nervosus belongs to the family of Polygonaceae,which is traditionally used in Ethiopia to treat various diseases. This prompted us to isolate bioactive compounds from the root of this plant. Ground root parts of Rumex nervosus were subjected to exhaustive extraction successively with petroleum ether and methanol.The solvent from each extract was evaporated under reduced pressure using rotavapour to obtain petroleum ether and methanol extract. Chromatographic purification of the methanol extracts by Column chromatography followed by Preparative Thin layer Chromatography using Chloroform: methanol (9.5:0.5) ratio gave a compound coded as RN-6. The structure of this compound 4-ethylheptyl benzoate was characterized as by means of 1H NMR, 13C NMR, UV and IR spectral data.


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