Journal of Natural Product Research and Applications

Antioxidant and cytotoxic activities of extracts from Haloxylon scoparium Pomel

2024-02-13T15:00:27+00:00

Haloxylon scoparium Pomel is a plant known to possess anti-cancer properties as well as anti-plasmodial and larvicidal activities. The aerial parts are used in traditional medicine to treat disorders and problems of the eye and vision, digestion problems, dermatoses, scorpion pitting. The antioxidant and anticancer activities of different extracts (dichloromethane, ethyl acetate and butanol) from flowers and stems were studied. The flowers exhibited strong antioxidant activity using the oxygen radical absorbance capacity method and a cell-based assay. The most interesting results are obtained with the ethyl acetate extracts of the flowers active with an ORAC value of 6.6 μmol TE / mg, followed by the butanol extract of the same organ (ORAC value of 6.22 μmol TE/ mg). The experiments carried out using the cellular antioxidant protocol reveal a very strong antioxidant activity, particularly for the ethyl acetate and butanol extract of the flowers with an IC₅₀ value of 0.029 ± 0.004 µg/ mL and 0.3 ± 0.1 µg/ mL respectively . The cytotoxic activity (Resazurin tests) was found to be moderate against A-549 (lung carcinoma) and DLD-1(colon carcinoma) cells, with IC₅₀ values of 110 ± 13 and 117 ± 14 μg/ mL, respectively. All the results obtained constitute a scientific justification for the use traditional of the plants studied and once again confirms the relevance of the remedies traditional in the treatment of many diseases.

Phytochemical study and evaluation of α-Amylase inhibitory effect of extracts from Cistanche violacea Desf.

2024-02-13T15:42:58+00:00

Cistanche violacea Desf. is a species of the family Orobanchaceae. It is an angiosperm dicotyledonous holoparasitic plant, which lacks chlorophyll. This work focuses on the search for an inhibitory effect of the enzymatic activity of α-amylase, in the presence of the crude water-methanol extract, of the underground part of C. violacea, prepared by maceration or decoction and its ethyl acetate fractions. Qualitative phytochemical tests and quantitative assays of phenolic compounds of the prepared extracts were performed. The effect of each extract on the activity of the α-amylase enzyme was evaluated under optimal conditions (pH 6.9 and T° 37°C). The results of phytochemical tests revealed the presence of tannins, flavonoids, free quinones, terpenoids and reducing compounds. The determination of phenolic compounds showed that the ethyl acetate extract prepared by maceration was the richest in total polyphenols and flavonoids with contents of the order of 82.937±6.750μg EqGA/mg D.W and 112.345±25.719μg EqC/mg D.W respectively. While the crude hydromethanolic extract prepared by maceration presented the highest content of condensed tannins (525.5±77.5μg EqC/mg D.W). On the other hand, the ethyl acetate extract prepared by decoction of the underground part of C. violacea showed a better inhibitory activity of the α-amylase enzyme, with IC₅₀ value of 1.88 mg/ml, compared to the other extracts tested. This activity remains low compared to acarbose (IC₅₀ = 0.132 mg/ml). We concluded that the roots of C. violacea exerts an inhibitory effect on α-amylase activity and thus on the regulation of hyperglycemia through a decrease in intestinal glucose absorption

Maceration, microwave assisted and ultrasound assisted extraction of phenolic compounds from Tunisian Limoniastrum monopetalum: kinetic modeling and chemical analysis

2024-02-13T16:06:21+00:00

Maceration, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) were investigated in this study, focusing on the selectivity towards phenolic compounds in ethanol extracts from Limoniastrum monopetalum leaves using the Folin-Ciocalteu method and kinetic models of extractions. Moreover, several phenolic compounds were identified by RP-HPLC. Results showed that total polyphenol compounds (TPC) under the MAE conditions (ethanol, 700 W microwave power, 60 s extraction time, and 1 mL/g solvent-to-solid ratio) were 75.707 mg GAE/100 g dried sample in only one minute of extraction. We conclude that MAE is a promising extraction method for polyphenols. Model results were correlated with mathematical models of the extraction process. Six phenolic acids and three flavonoids were identified by HPLC–DAD. MAE is a valuable and green analytical methodology for the investigation of phenolic components in natural plants.

In vitro antioxidant and antidiabetic activities of the hydro-acetone extracts of Ricinus communis and Teucrium polium from Tlemcen area

2024-02-13T16:20:54+00:00

The aim of the present study was to determine total phenolic and total flavonoid contents in hydro-acetone extracts from the roots of Ricinus communis and the aerial part of Teucrium polium, and to determine in vitro their antioxidant and antidiabetic activities using DPPH, FRAP, and α-amylase activity assay, respectively. The obtained results reveled that R. communis roots hydro-acetone extract contains high contents of polyphenols (499.55 ± 0.02 µg GAE/mg DE) and flavonoids (28.21 ± 0.01 µg Cat eq/mg DE) than T. polium aerial part extracts. Both plant extracts showed in vitro antioxidant and antidiabetic activities, where R. communis showed a potent free radical scavenging activity (DPPH IC₅₀=2.01 ± 0.01 µg/mL) and high iron reduction capacity (FRAP EC₅₀=41.32 ± 0.01 µg/mL) more than T. polium extract (DPPH IC₅₀= 7.40 ± 0.01 µg/mL; FRAP EC₅₀=74.63 ± 0.01 µg/mL). In addition, in α-amylase activity assay T. polium was more efficient in inhibiting this enzyme (EC₅₀= 924 ± 0.19 µg/mL) compared to R. communis extract (EC₅₀= 1300 ± 0.03 µg/mL).

Phycochemistry study and antimicrobial activity of Spirogyra freshwater green microalgae from Algeria

2024-02-13T16:41:04+00:00

In Algeria, algae have not been adequately explored for their potential as a source of bioactive substances. In this context the blooms of green alga Spirogyra sp. were collected from freshwater habitats in Oued El Mellah near M’sila province of Algeria. Hexane, acetone and ethanol crude extracts were screened for antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi and Candida albicans. The contents of total soluble sugars, soluble proteins, total lipids and phenolic acids were also determined. The present findings revealed that the highest extraction yield was obtained from ethanol (4.93%) compared to acetone (3.67%) and hexane (2.33%). The contents of phycochemical compounds were 32.5% of soluble carbohydrates, 15.84% of lipids, 15.6% of phenolic acids and 5.16% of proteins. All extracts exhibited better and stronger antibacterial activities against the five pathogenic bacteria with inhibition zones diameter ranged from 13.5-29 mm for acetone extract, from 13-25 mm for ethanol extract and from 12.5-20.5 mm for hexane extract at 7.5 µL. The minimal inhibitory concentration (MIC) was in the range of 15-40 mg mL^-1. The acetone extract was more effective than others extracts with MIC value of 15 mg mL^-1 for all bacteria. These findings indicate the presence of promising antibacterial compounds originating from microalgae, which can be exploited for the production of new antimicrobial agents.