An Efficient Two-Step Synthesis of Jensenone Isolated from Eucalyptus jensenii. Synthesis of Analogues and Evaluation as Antioxidants

2005 ◽  
Vol 58 (7) ◽  
pp. 551 ◽  
Author(s):  
Sandip B. Bharate ◽  
Siddheshwar K. Chauthe ◽  
Kamlesh K. Bhutani ◽  
Inder P. Singh

A phloroglucinol derivative, jensenone (1) isolated from leaves of Eucalyptus jensenii has been synthesized for the first time through a short and efficient two-step procedure starting from commercially available phloroglucinol. The methodology provides a simplified route to introduce diformyl moiety for synthesis of biologically active formylated phloroglucinol compounds such as antimalarial robustadials, cancer chemopreventive euglobals, and antifouling sideroxylonals. Several analogues of jensenone have also been synthesized and evaluated for antioxidant capacity.

2018 ◽  
Vol 1 (1) ◽  
pp. 11 ◽  
Author(s):  
Kostadinka B. Karneva ◽  
Ivelina N. Vasileva ◽  
Petko N. Denev ◽  
Rositsa S. Denkova ◽  
Vasil T. Shikov ◽  
...  

Bulgaria became the leading producer of lavender oil in the last years. Due to the lower quantity of essential oil large amounts of waste were generated which distilleries usually discard, although the residues are rich source of biologically active substances. The objective of this study was to obtain polyphenol-rich extracts from lavender waste and to investigate their chemical composition and antioxidant capacity. Two wastes (Mirkovo, Bulgaria, 2016) were investigated – steam distilled (SD-L) and CO2-extracted lavender (CO2-L). The major aroma constituents found were linalool and linalyl acetate – 30.68% and 25.82%, respectively, and the highest concentrations were found in the SD-L. The total flavonoids in CO2-L and SD-L were 2.91±0.11 and 3.72±0.20 mg/g dry matter residue, respectively. The higher amount of phenolic acids was observed in the SD-L waste – 2.62±0.19 mg/g, compared to 1.39±0.14 mg/g dry matter residue for CO2 extracted lavender. The antioxidant activity of the extracts was investigated by DPPH (SD-L – 355.48±23.12 µmol TE/g DW waste; CO2-L – 283.21±17.04 µmol TE/g DW waste) and FRAP (SD-L – 427.36±26.54 µmol TE/g DW waste; CO2-L – 311.29±18.17 µmol TE/g DW waste). Both methods suggested that SD-L residue had higher antioxidant capacity and polyphenol content.The lavender wastes (SD-L and CO2-L) showed strong antioxidant capacity with potential beneficial effect on addition in foodstuffs. For the first time lavender residues from CO2-extraction was investigated for its antioxidant activity, polyphenol composition and aroma metabolites, and comparison with SD-L was performed. In general, the results suggested that the lavender waste were promising source of antioxidants.


Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 783
Author(s):  
Ying Duan ◽  
Chen Wang ◽  
Jian Hao ◽  
Yang Jiao ◽  
Yanchao Xu ◽  
...  

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 681
Author(s):  
Paulo Gomes ◽  
Luis Quirós-Guerrero ◽  
Abraão Muribeca ◽  
José Reis ◽  
Sônia Pamplona ◽  
...  

Chamaecrista diphylla (L.) Greene (Fabaceae/Caesalpiniaceae) is a herbaceous plant that is widely distributed throughout the Americas. Plants from this genus have been used in traditional medicine as a laxative, to heal wounds, and to treat ulcers, snake and scorpion bites. In the present study, we investigated the chemical composition of Chamaecrista diphylla leaves through a mass spectrometry molecular network approach. The oxygen radical absorbance capacity (ORAC) for the ethanolic extract, enriched fractions and isolated compounds was assessed. Overall, thirty-five compounds were annotated for the first time in C. diphylla. Thirty-two of them were reported for the first time in the genus. The isolated compounds 9, 12, 24 and 33 showed an excellent antioxidant capacity, superior to the extract and enriched fractions. Bond dissociation energy calculations were performed to explain and sustain the antioxidant capacity found. According to our results, the leaves of C. diphylla represent a promising source of potent antioxidant compounds.


Author(s):  
Maltseva E.M. ◽  
Egorova I.N. ◽  
Pinchuk L.G.

Pale-flowered licorice (Glycyrrhiza pallidiflora Maxim.) is the pea family (Fabaceae) perennial herb. It is a Russian Far East endemic. Pale-flowered licorice refers to the false (not sweet) licorice section (Pseudoglycyrrhiza Krug.), which do not accumulate glycyrrhizin derivatives. The G. pallidiflora successful introduction has been carried out over the past 5 years in the “Apothecary garden” territory, FRC UUH SB RAS, Kemerovo. Phytochemical studies screening biologically active compounds main classes of the plant aerial part confirmed the presence of a complex of phenolic compounds. The content of catechin derivatives and condensed-type tannins - proanthocyanidins (PAC) data in G. pallidiflora herb were obtained for the first time. In different years of cultivation, licorice herb accumulates phenolic compounds - up to 2.83 ± 0.22% in terms of gallic acid, flavonoids - up to 2.44 ± 0.03% in terms of rutin and PAC in terms of cyanidine chloride - up to 2.61 ± 0.11%. It was found that the maximum content of the phenolic compounds and PAC sum was observed in the herb for 4 years development. The greatest number of flavonoids accumulates in the herb harvested in the 3rd year of cultivation. A positive significant linear relation was found between antioxidant activity (AOA) and the total phenolic compounds and PAC content (r≥0.98). Considering that BAC with IC values ≤ 50 μg / ml in the DPPH assay refer to active antioxidant’s licorice herb can be classified as a plant with high antioxidant potential. It was found that the iron chelating activity of the G. pallidiflora herb is in direct dependence (r≥0.94) on the content of flavonoids. The obtained results demonstrate the importance of further study of this plant as a source of BAC, including plant antioxidants.


eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Albert Lu ◽  
Paulina Wawro ◽  
David W Morgens ◽  
Fernando Portela ◽  
Michael C Bassik ◽  
...  

Extracellular vesicles mediate transfer of biologically active molecules between neighboring or distant cells, and these vesicles may play important roles in normal physiology and the pathogenesis of multiple disease states including cancer. However, the underlying molecular mechanisms of their biogenesis and release remain unknown. We designed artificially barcoded, exosomal microRNAs (bEXOmiRs) to monitor extracellular vesicle release quantitatively using deep sequencing. We then expressed distinct pairs of CRISPR guide RNAs and bEXOmiRs, enabling identification of genes influencing bEXOmiR secretion from Cas9-edited cells. This approach uncovered genes with unrecognized roles in multivesicular endosome exocytosis, including critical roles for Wnt signaling in extracellular vesicle release regulation. Coupling bEXOmiR reporter analysis with CRISPR-Cas9 screening provides a powerful and unbiased means to study extracellular vesicle biology and for the first time, to associate a nucleic acid tag with individual membrane vesicles.


Author(s):  
С. В. Шершова

Проведено експериментальне обґрунтування біо-конверсії відходів вирощування (полови) ехінацеїпурпурової (Echinacea purpurea (L.) Moench.) таехінацеї блідої (Echinacea pallida (Nutt) Nutt.).Доведена висока активність екстрактів полови зехінацеї пурпурової, що проявлялася у стимуляціїросту тест-культури. Встановлено, що найвищустимулюючу активність мають екстракти поло-ви ехінацеї пурпурової: водні за концентрації0,01 %, спиртові – 0,01–0,001 %; до того ж іззбільшенням концентрації спирту в екстрактахзнижувалась їх активність. Вперше встановлено,що полова ехінацеї містить специфічні білки –лектини, активність яких у відходах ехінацеї блі-дої значно перевищувала ехінацею пурпурову. Роз-роблено технологічні схеми отримання лектинівта екстрактів біологічно активних речовин із від-ходів вирощування (полови) для їх ефективноговикористовування. The experimental foundation bioconversion of waste product of growing (chaff), purple coneflower(Echinacea purpurea (L.) Moench.) and pale coneflower (Echinacea pallida (Nutt.) Nutt.) was to carriedout. The high activity of extracts of coneflower chaff, which had growth-stimulating effect to the testculture, was proved. Found that the highest stimulating activity has the extract of chaff purpleconeflowers: aqueous solution at concentrations of 0.01 %, alcohol-0.01 %-0.001 % and with increasingconcentration of alcohol in the extracts decreased their activity. For the first time it has been shown thatchaff of Echinacea contains specific proteins - lectins, and their activity in the waste product of paleconeflower significantly exceeded then activity in the waste product of purple coneflower. Technologicalschemes to get of lectins and extracts of biologically active substances from waste growing product(chaff), was worked out for their effective use.


2017 ◽  
Vol 75 (1) ◽  
pp. 17-22
Author(s):  
Dorota Sołtys-Kalina

Abstract In the laboratory studies on allelopathy, phytotoxicity is defined as a negative impact of plant’s extracts or natural compounds derived from plants, on germination and/or growth of the tested (acceptor) plant. Glycoalkaloids are the main biologically active compounds of the potato and are involved in potato phytotoxicity (the correlation coefficient of the length of the test plant with the concentration of total glycoalkaloids present in the leaf extracts of forty potato genotypes was r = -0.41). The assessment of phytotoxic abilities of the potato is a two-step procedure which consists of determining glycoalkaloids in potato leaf extracts and analyzing the root and hypocotyl lengths of the test plant growing in potato leaf extracts.


2021 ◽  
Vol 38 ◽  
pp. 00033
Author(s):  
Tatiana Fomina ◽  
Tatiana Kukushkina

The content of the major groups of biologically active substances in flowers of 7 Campanula species, cultivated in the forest-steppe of Western Siberia, were investigated for the first time. Freshly collected flowers were found to contain 0.06-0.15 % of catechins, 0.31-3.17 % of flavonols, 3.31-6.47 % of tannins, 3.10-15.57 % of pectic substances, and 0.66-16.4 mg% of carotenoids calculated per absolute dre weight of raw material. The amount of ascorbic acid was 36.9-114.0 mg% per wet weight. The data indicate that Campanula flowers are promising for the production of phenolic compounds, the development of food additives and fresh consumptions a seasoning.


2017 ◽  
Vol 112 (3) ◽  
pp. 121-128
Author(s):  
Dorota Martysiak-Żurowska ◽  
Małgorzata Puta ◽  
Anna Rodzik ◽  
Edyta Malinowska-Pańczyk

Human milk is rich in polyunsaturated fatty acids, as well as lysozyme, vitamin C and other bioactive compounds. The effect of lyophilization on the content of antioxidants (vitamin C and catalase CAT), bactericidal compounds (lysozyme), total antioxidant capacity (TAC) and lipid peroxidation in human milk was investigated in this study. Samples of mature human milk were collected from five healthy women who gave birth on the scheduled date and without complications. Freeze drying resulted in the removal of 88.2 % of the initial water content from milk. The human milk lyophilizate was readily soluble in water. Lyophilization had no effect on the content of primary (lipid peroxides LP) and secondary (thiobarbituric acid reactive substances TBARS) products of lipid oxidation. Freeze-drying led to a significant decrease in the vitamin C content and TAC values of milk (by 31 % and 16.5 %, respectively). Catalase and lysozyme were resistant to freeze-drying. Lyophilization induced a decrease in lysozyme content (9 %) and catalase activity (11 %) but these changes were not statistically significant. Low-temperature dehydration and rehydration of human milk lyophilizates promote satisfactory retention of biologically active ingredients and prevent the oxidation of human milk lipids. The results of this study indicate that lyophilization can be considered as an effective method for prolonging the shelf life of human milk.


2014 ◽  
Vol 13 (1) ◽  
pp. 27
Author(s):  
WaillA Elkhateeb ◽  
MohamedB Mazen ◽  
Mohamed Hashem ◽  
GhosonM Daba ◽  
Abdel-NasserA Zohri

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