Phytochemical profile, in vitro antioxidant and antibacterial activities of different extracts of an Algerian endemic: Teucrium atratum.

Teucrium atratum Pomel. is a species belonging to the Lamiaceae family used in Algerian folk medicine. The present work essentially aimed to assess the phenolic composition and to evaluate some of the biological effects of different extracts, never previously studied, of T. atratum growing in Algeria. High levels of total phenolic and flavonoids were recorded in the hydromethanolic extract. Chlorogenic acid, isoquercetin, coumarin, cinnamic acid, quercetin dihydrate, and catechin were identified in the methanolic extract by mean of HPLC. The antioxidant activity assessed showed that the methanolic extract was the most active, while, the hydromethanolic extract showed a great power to reduce iron. In addition, all extracts had a significant antibacterial effect against the four tested bacterial strains, with Staphylococcus aureus as the most sensitive one. These findings can be a starting point to evaluate the plant as a source of natural bioactive compounds with antioxidant and antibacterial effects.

Biopolymer- and Lipid-Based Carriers for the Delivery of Plant-Based Ingredients.

Natural ingredients are gaining increasing attention from manufacturers following consumers' concerns about the excessive use of synthetic ingredients. However, the use of natural extracts or molecules to achieve desirable qualities throughout the shelf life of foodstuff and, upon consumption, in the relevant biological environment is severely limited by their poor performance, especially with respect to solubility, stability against environmental conditions during product manufacturing, storage, and bioavailability upon consumption. Nanoencapsulation can be seen as an attractive approach with which to overcome these challenges. Among the different nanoencapsulation systems, lipids and biopolymer-based nanocarriers have emerged as the most effective ones because of their intrinsic low toxicity following their formulation with biocompatible and biodegradable materials. The present review aims to provide a survey of the recent advances in nanoscale carriers, formulated with biopolymers or lipids, for the encapsulation of natural compounds and plant extracts.

In vitro and in vivo bioactivities of Ambrosia maritima and Bituminaria bituminosa organic extracts from Algeria.

INTRODUCTION: Two medicinal plants, Ambrosia maritima and Bituminaria bituminosa, growing in Algeria were investigated for their flavonoids content and their biological activities. METHODOLOGY: Different organic extracts were prepared from the aerial parts of each plant using maceration method followed by liquid/liquid type extractions. The anti-antioxidant activity was tested using the ß-carotene bleaching method. The anti-inflammatory activity was tested by performing the protein anti-denaturation assay. Acute toxicity and immunostimulatory effect were tested in mice, while the antimicrobial activity was tested according to the minimal inhibition concentration technique. RESULTS: In term of flavonoids content, ethyl acetate extract of B. bituminosa was the highest (193.39 ± 24.1 µg QE/mg). Ethyl acetate extract of A. maritima showed antioxidant activity with IC50 value of 11.72 ± 0.79 µg/mL. The hydroethanolic extract of A. maritima showed the best anti-denaturation effect in a dose-dependent manner with the IC50 value of 131.07 ± 0.027 µg/mL. The studied plants showed no toxicity or mortality in vivo. Both plants showed a significant immunostimulatory effect; while the Butanolic extract of B. bituminosa demonstrated the best antimicrobial activity against Staphylococcus aureus and Candida albicans strains. CONCLUSIONS: We recommend A. maritima and B. bituminosa as potent sources of antioxidants and as antimicrobial agents for further assays to better elucidate their actions on the immune system.

HPLC-DAD-ESI/MS profiles of bioactive compounds, antioxidant and anticholinesterase activities of Ephedra alata subsp. alenda growing in Algeria.

Ephedra (Ephedraceae) is used in medicine for various purposes as having, antioxidant, anticarcinogen, antibacterial, anti-inflammatory hepatoprotective, anti-obesity, antiviral and diuretic activities. In this study the aim was to investigate chemical constituents of Ephedra alata and understand the possible effects of those constituents in antioxidant activity and alzheimer's disease essay. For this purpose, natural compounds from E.alata were characterized by LC-DAD-ESI-MS/MS using negative and positive ionization modes, while the bioactivity was assessed by acetylcholinesterase (AChE) inhibition study and determining of antioxidant activity; DPPH radical scavenging and ß-carotene bleaching assays were used to assess the antioxidant potential. The proposed method of spectrometry provided tentative identification of 27 compounds including alkaloids and phenolic compounds as flavonoids. The methanolic extract showed high contents of total phenolic and exhibited an important antioxidant potential and demonstrated a potent inhibitory effect against acetylcholinesterase (IC50: 11,25 ± 0,25 µg/mL). The results showed that the plant possesses a therapeutic effect.

Formulation and characterization of zein/gum arabic nanoparticles for the encapsulation of a rutin-rich extract from Ruta chalepensis L.

Rutin, a plant flavonol characterized by a wide range of biological effects, has limited application in foods because of its low water solubility and scarce bioavailability. This work aimed to investigate the encapsulation of a rutin-rich extract (200.6 ±â€¯1.5 mg/g of rutin) from Ruta chalepensis L. in zein nanoparticles (hydrodynamic diameter of 80-170 nm) prepared by antisolvent precipitation and stabilized by gum arabic (GA). The addition of GA (1:1 mass ratio with zein) significantly reduced the instability phenomena of zein nanoparticles through the deposition of a negatively charged layer as evidenced by the zeta potential and the UV-visible measurement, suggesting an electrostatic interaction between zein and GA. It also contributed to enhancing the encapsulation efficiency of rutin and inducing a rapid release during simulated digestion. These findings show that zein/GA nanoparticles represent a promising delivery system for natural extracts, fabricated through a facile and versatile process.

Fiaud's Acid, a novel organocatalyst for diastereoselective bis α-aminophosphonates synthesis with in-vitro biological evaluation of antifungal, antioxidant and enzymes inhibition potential.

(S, S)-1-hydroxy-1-oxo-2-c,5-t-diphenylphospholane or Fiaud's acid is used as a novel and effective chiral organocatalyst for bis α-aminophosphonates synthesis with excellent diastereoselectivity and yields within short reaction time. All synthesized bis α-aminophosphonates revealed a good to excellent antifungal capacity, where the six compounds 4a, 4b, 4e, 4h, 4k and 4l are the best fungicide inhibiting the growth of Fusarium oxysporumandBotrytis cinereaby 65% to 84% with IC50 values <0.02 mg/mL. Similarly, these six products exhibited a strong antioxidant effect, whereas a low inhibition activity was obtained with both AChE and BChE. Furthermore, they displayed a very weak inhibitory activity against tyrosinase except for the compound4l.These findings suggest a possible use of these compounds as synthetic pesticides with less hazardous effects with antioxidant, and anti-tyrosinase properties.

Evaluation of antidiabetic effect of total calystegines extracted from Hyoscyamus albus.

BACKGROUND: Hyoscyamus albus L. (Solanaceae) an old medicinal plant is a rich source of tropane and nortropane alkaloids which confers to this plant a number of very interesting and beneficial therapeutic effects. PURPOSE: Calystegines that are polyhydroxylated alkaloids and imino-sugars poccess significant glycosidases inhibitory activities and are therefore good candidats for the treatment of diabetes mellitus. STUDY DESIGN: Calystegines extracted from Hyoscyamys albus seeds were tested for teir acute oral toxicity and investigated for their in-vivo antidiabetic effect on Streptozotocine induced diabetes in mice. METHODES: Calystegines were extracted from the seeds plant using an Ion exchange column; the remaining extract was then administrated orally to mice at several single doses for acute toxicity assay. A dose of 130mg/kg streptozotocine was injected to mice to induce diabetes mellitus, and diabetic mice were treated orally during 20days with 10mg/kg and 20mg/kg calystegines and 20mg/kg glibenclamide as the reference drug. RESULTS: Acute oral toxicity showed that calystegines are not toxic up to a dose of 2000mg/kg with absence of any signs of intoxication and damages in Liver and kidney tissues. The nortropane alkaloids markedly reduced blood glucose levels and lipid parameters of diabetic mice to normal concentrations after 20days of treatment at 10mg/kg and 20mg/kg (p<0.05). Histopathological study of diabetic mice pancreas indicated that calystegines of Hyoscyamus albus have minimized streptozotocine damages on ß-cells of islets of langerhans, stimulated ß-cells regeneration and improved with this insulin secretion. CONCLUSION: The findings of this study suggest that calystegines are potent antidiabetic agents with antihyperglicemic and hypolipidemic effects, and a protective fonction on pancreas in streptozotocin induced diabetes in mice.