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Saffron is widely used for its medicinal and culinary properties. Its stigmas are the most expensive part comparing with the flowers that are discarded during production. For that, the objective of this work was to determine the phytocomplex of stigma and flower material (except stigma) of saffron from Algeria. Crocin, picrocrocin and safranal contents were quantified to classify its quality according to ISO/TS 3632 standards. The antioxidant and antimicrobial properties of extracts were also investigated. Crocins, total phenolic content, flavonoids, phenolic acids, and anthocyanins were detected and quantified by HPLC-DAD and spectrophotometric analyses. The antioxidant potential was evaluated by 4 in vitro assays. The antimicrobial activity against seven bacteria and two strains of Candida albicans was also evaluated. The results revealed that the chromatographic analysis showed the presence of 20 phenolic acids and flavonoids in the plant samples, with the highest concentrations in stigmas. Crocin derivatives were found only in stigmas, except that trans-crocetin (β-D-gentiobiosyl) which was present also in flower material. The highest total phenolic, total flavonoid and total flavonol contents were observed in stigmas and the highest level of anthocyanins and hydrolysable and condensed tannins in flowers. This extract showed a stronger protection effect from β-carotene bleaching and a higher TAC. The both extracts had some antimicrobial effect. These results point out that flower material could be considered as natural bioresource of polyphenolic compounds, with higher biological activities which remain to be exploited.

Effects of extraction solvent and harvest period on phytochemical analysis and antioxidant and antimicrobial activities of extracts obtained from the freshwater macroalga, Spirogyra sp. were evaluated. The experiment lasted five months, where five crude extracts were obtained by maceration using different solvents: hexane, chloroform, dichloromethane, acetone and methanol. Higher values of yields were recorded in methanolic extracts on February (7.304%) and March (4.812%). All extracts were rich in proanthocyanidins compared to total phenolics and flavonoids. The total amounts of carotenoids were very low (0.060 ± 0001 to 0.171 ± 0.005 mg/g) compared to chlorophylls which were higher in February (6.365 ± 0.075 mg/g) and in March (5.501 ± 0.118 mg/g). The antioxidant activities indicated that the chloroformic and dichloromethanic extracts of February and March exhibited a good activity. The correlation using the Pearson test of phenolic compounds and antioxidant activity tests have confirmed the strong contribution of flavonoids and proanthocyanidins. The greatest antimicrobial activity was found in hexanic extracts at 0.1 to 1 mg/disk. The present findings suggest that Spirogyra sp. can be exploited not only for human health, but also for screening new economic natural antioxidants that could be used in foods, cosmetics and pharmaceutical industries.

Background The constant development of microbial resistance to the traditional antimicrobial agents and the emergence of new infectious diseases justify the urgent need for new effective antimicrobial molecules. However, the irrational use of antibiotics increases microbial resistance dramatically and along with that the frequency of mortality associated with infections is higher. Therefore, to combat the antimicrobial resistance, the screening of compounds with novel chemical structures is essential. This study intended to determine the antimicrobial potential of Streptomyces GLD22 strain isolated from Algeria. Methods The characterization of Streptomyces strain GLD22 was performed by physiological, biochemical and molecular tests. The antimicrobial activity was tested by the well diffusion method and the minimum inhibitory concentration value calculation were performed using broth micro dilution technique. The extracellular metabolites profiling was done using GC–MS. Results Physiological, biochemical and phylogenetic analysis confirmed that the strain GLD22 showed maximum identity towards Streptomyces species. The extra cellular metabolites revealed their antimicrobial activity at 1 mg/ml for Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, whereas Staphylococcus aureus, Bacillus cereus and Bacillus subtilis documented 0.5, 1 and 1 mg/ml respectively. GC–MS analysis confirmed that 2-tert-butyl-4,6-bis(3,5-di-tert-butyl-4-hydroxybenzyl) phenol, Dibutyl phthalate and Cyclo(leucyloprolyl) were the major drug molecules present in the extract. Conclusion The novel Streptomyces strain GLD22 recovered from the Gueldaman cave of Algeria showed better antimicrobial activity towards both Gram positive and Gram negative pathogens. Interestingly, the MIC values were comparable with the standard drug molecules. In addition, the identification of active metabolites present in the crude extracts was an advantage.

The current study was carried out to investigate the chemical composition of Pistacia lentiscus fruit fatty oil by HPLC–DAD and GC analysis. The quantification of phenolic content and DPPH radical scavenging capacity of this oil were furthermore evaluated. The results showed that the oil has the highest phenolic content (810 mg GAE/kg oil). The capacity to scavenge DPPH radical was admissible (EC50 = 20.619 ± 0.312 mg/mL), compared to the butylated hydroxyanisole (BHA) (0.012 ± 0.0001 mg/mL). The main fatty acids where oleic, palmitic, linoleic, palmitoleic and stearic acids which have specific carbon number and their values in percentage are C18:1 n-9 (50.02 ± 0.55%), C16:0 (24.83 ± 1.25%), C18:2 n-6 (17.24 ± 0.10%), C16:1 n-7(1.55 ± 0.09%) and C18:0 (1.08 ± 0.02%), respectively. The analyses showed concentrations of approximately 26% of saturated fatty acids, 52% of monounsaturated and 18% of polyunsaturated.

The antioxidant activity of the crude hydroalcoholic extract (PSMW) and its derived fractions n-hexane (PSH), diethylic ether (PSDE), chloroforme (PSC), ethyl acetate (PSEA), n-butanol (PSB) and residual aqueous fraction (PSA) of aerial part of endemic plant Pituranthos scoparius was performed using three in vitro tests : phosphomolybdate assay, reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging capacity. The total yield, total phenolic (TPC), flavonoid (TFC), flavonol (TF) and condensed tannin contents (TCT) of all the fractions were also determined. This plant was also subjected to preliminary phytochemical screening test for various constituents. Phytochemical screening revealed the presence of flavonoids, tannins, coumarins, saponins and steroids in the extracts. Amongst the extracts, PCMW showed the highest TPC (8.40 ± 0.01 mg gallic acid equivalent/g of dry matter), TFC (2.25 ± 0.01 mg catechin equivalent/g), TF (1.19 ± 0.04 mg quercetin equivalent/g) and TCT (1.07 ± 0.16 mg catechin equivalent/g). The Total Antioxidant Capacity (CAT) was found to be varied in different fractions from 0.11 ± 0.00 to 10.02 ± 0.02 mg ascorbic acid equivalent/g). Therefore, PSEA showed the highest antioxidant activities to reduce iron (IC50 = 1.19 ± 0.00 mg/mL) and to scavenge DPPH (IC50 = 0.91 ± 0.02 mg/mL).

Anabasis articulata is a plant widely used in popular medicine to treat several pathologies in Algerian Sahara, such as diabetes. It is also associated with two other plants to cure certain types of cancer. Few research studies have been conducted on phytochemical analysis and in vivo biological activities of this species. However, no report is available on chemical elucidation of alkaloids and their antioxidant and antimicrobial properties. This study aims to characterise alkaloids in A. articulata stems and to evaluate their antioxidant and antimicrobial effects. Alkaloids extraction was carried out using polar (E1; E2.1; E2.2) and apolar solvents (E3), while chemical characterisation was performed by GC/MS. In vitro antioxidant activity was assessed by tree tests: total antioxidant capacity (TAC), DPPH scavenging assay and β-carotene–linoleate inhibition. For antimicrobial activity, eight different microorganisms were tested. The results suggest that E2.2 extract had the highest TAC value (14.742 ± 0.224 mg AAE/g DM), but E3 extract presented the highest DPPH scavenging activity (EC50 = 1.242 ± 0.168 mg/mL) and a strong β-carotene–linoleate inhibition (EC50 = 0.943 ± 0.027 mg/mL). In addition, E3 extract had the strongest inhibitory effects against all tested microorganisms and produced inhibition zones ranging between 9 and 20 mm, while the MICs of this extract ranged from 0.781 to >100 mg/mL and the MBCs ranged between 1.562 and >100 mg/mL. Forty-nine compounds belonging to 16 families, namely cyclopeptide alkaloids, steroid alkaloids, quinoline alkaloids, camptothecin alkaloids, quinazoline alkaloids, quinazoline alkaloids, isoquinoline alkaloids, isoquinolone alkaloids, indole alkaloids, terpene indole alkaloids, pyridine/pyrrolidine alkaloids, piperidine alkaloids, pyrrolizidine alkaloids, purine alkaloids, acridone alkaloids, benzazonine alkaloids and homolycorine-type Amaryllidaceae alkaloids were identified. Therefore, A. articulata can be considered as a source of antioxidant and antimicrobial agents.

The aim of the current study is to analyze the phytochemical, antioxidant and antimicrobial activities of 34 extracts prepared from Pistacia atlantica Desf. subsp. atlantica, according to gender, organ type (roots, buds and fruits), geographical location and stage of ripening. Bud extracts exhibited the highest phenolic content (565.74 ± 9.84 mg GAE/g DM), followed by fruit and root extracts. TFC and TTC ranged from 0.38 ± 0.03 to 1.92 ± 0.11 mg CE/g DM and from 0.37 ± 0.03 to 16.54 ± 0.94 mg CE/g DM, respectively. For DPPH and TAC assays, the values varied from 0.038 ± 0.000 to 1.331 ± 0.114 mg/mL and 1.58 ± 0.06 to 43.64 ± 2.58 mg AAE/g DM, respectively. Besides, bud extracts showed the highest bioactivity against pathogenic bacteria and a slight antifungal effect. Additionally, HPLC-DAD analysis revealed that the caffeic acid and the dimethyl-allyl caffeic acid characterized the bud extract, while the rutin and the hydroxytyrosol were abundant in the red fruit extract. The present evidence suggests that P. atlantica may be considered as a potential source of new additives for therapeutic, food and cosmetic products.

The chemical composition of 93 oil samples from the aerial parts of Pituranthos scoparius, harvested in three regions of Algeria, was investigated by GC-FID, GC/MS and 13 C-NMR. Monoterpene hydrocarbons dominated in association with phenylpropanoids and a chemical variability was found highlighting three clusters. The composition of group I (36 samples) exhibited an atypical composition characterized by a very high contents of 6-methoxyelemicine (13.0 - 59.6%), followed by sabinene (1.1 - 43.0%) and limonene (6.6 - 39.0%), while the samples of group II (12 samples) contained a high content of limonene (9.2 - 44.0%), followed by myristicine (0.0 - 29.4%) and a lower amount of sabinene (0.8 - 2.3%). Group III (45 samples) could be divided in two subgroups. Subgroup SGIIIA was characterized by a very high content of sabinene (28.0 - 55.6%), followed by elemicine (0.0 - 29.1%), while the samples belonging to SGIIIB were characterized by the lower content of sabinene (6.2 - 35.5%) and a significant content of myristicine (1.5 - 32.4%), α-pinene (4.2 - 31.0%) and dill apiole (0.1 - 31.4%). Each harvested region was characterized by a different chemical composition.

The aim of this study is to evaluate the in vitro effects of aqueous extracts of three species of Algerian desert truffles (Terfezia claveryi, T. leonis, and Tirmania nivea) on the growth of Pseudomonas aeruginosa and Staphylococcus aureus. The antimicrobial activity of the three aqueous extracts was tested using the agar well diffusion and kinetic bacterial growth curves methods. The aqueous extracts of Terfezia claveryi and Tirmania nivea were found to possess a very powerful antibacterial activity against both S. aureus and P. aeruginosa using agar well diffusion. Using 4% and 11% of the aqueous extracts of T. claveryi and T. nivea in the growth medium of S. aureus caused a significant inhibition of S. aureus growth by 86.48% and 99.09%, respectively. The aqueous extracts of T. claveryi and T. nivea were found to cause a significant inhibition of the growth of P. aeruginosa by 71.11% and 100%, respectively. However, the aqueous extract of Terfecia leonis did not show any antibacterial activity. Therefore, T. claveryi and Tirmania nivea can be considered a source of natural therapeutic agents that can be used to treat eye infections caused by resistant bacteria such as P. aeruginosa and S. aureus.