On this study, heated reflux extraction method has been used to identify the phenolic compounds from C. humilis var. argentea leaflets, rachis and fruits. Extractions were performed in both ultrapure water and 80% methanol solvents. The efficiency of procedures was determined in terms of the quality and quantity of phenolic acids and flavonoids identified. Chamaerops extracts have been characterized by high concentrations of phenolic compounds, which play a crucial role in protection against various diseases. LC-MS/MS was used to determine the chemical profile of various extracts obtained from Chamaerops. The results showed that the major components in leaflets and fruits extracts were quinic, malic and chlorogenic acids. On addition, nine minor acidic components were identified. Dn the other hand, rutin and hesperidin were found to be the major flavonoids. The methanol extract was shown as being the most efficient to identify phenolic compounds in C. humilis. Keywords: Chamaerops humilis L.; LC-ESO-MS/MS; phenolic compounds; chemical composition; extracts.Practical Application: Chamaerops humilis L. rich in flavonoids and phenolic acids was a great promising source of different bioactive components.

The frequencies of wildfires in the Mediterranean climate regions (MCRs) have amplified due to the increased temperatures and drought periods resulting from climate change. Vast areas of forests are consumed by wildfires and certain species are threatened by extinction due to their high flammability and weak thermotolerance to climate change whereas, other species with high thermotolerance are exploited as silviculture measures in forest management strategies. Canopy and litter foliage are the first ignitable structures in a forest fire. In this context, the foliar flammability characteristics of two fire resilient Mediterranean forest species are tested and compared on a laboratory scale; Quercus suber L. (Q.s.L.) and Cupressus sempervirens L (C.s.L). Thermo gravimetric/thermo differential analysis (TGA/TDA) and low- to high- temperature analytical pyrolysis tests and gas chromatography-mass spectrometry (GC-MS) were conducted on live and dry foliar samples of Lebanese C.s.L and Algerian Q.s.L. Branch and cork samples of Q.s.L were also pyrolyzed (Pyr/GC-MS) for their volatile content. The hemicellulose/cellulose degradation temperatures of C.s.L. were in the order of 30 to 50°C more than those of Q.s.L. Lignin degradation started later in the Q.s.L. and took place at temperatures higher than those of C.s.L. (>30°C), while the heat release rates (HRR) were greater for the latter than the former in both degradation phases. The pyrolysis tests showed higher volatile content of C.s.L compared to Q.s.L. The high thermotolerance characteristic of C.s.L may be referred to its high terpene content which was negligible in Q.s.L given the fact that it is a non-monoterpene emitter oak species with no terpene storage compartments. The use of C.s.L as a fire barrier could be justified given their thermotolerance characteristic. Q.s.L. fire resilience is justified for their bark characteristics however; their foliage fire resilience should be further experimented.

No abstract

Retama monosperma is a fabaceous shrub that colonizes dune sands owing to its particularly important root system at depth and on the surface. It establishes symbiotic associations with rhizobia and thus plays a role in the bio -fertilization of soils. The stem fibers of R. monosperma are an interesting material for industry because of their useful biometric, physical, chemical and structural characteristics. The aim of this study was to complete these data with a biochemical analysis of the cell walls tissues of adult branches of R. monosperma. Cellulose, hemicelluloses and pectins were extracted from cell wall. The weight dosage indicated that cellulose remained the major component of the wall (56% from the crude cell wall and 52% from the delignified cell wall) ahead of hemicelluloses (16% from the crude cell wall and 14% from the delignified cell wall) and pectins (5.6% from the crude cell wall and 5% from the delignified cell wall for water extract pectins and 3% from the crude cell wall and 2.4% from the delignified cell wall for oxalate extract pectins). The colorimetric assay of pectins extracted from lignified cell wall of R. monosperma suggested presence of more uronic acids (14.95µg/mL) than pectins extracted from a delignified cell wall (12.37 µg/mL). Gas chromatographic analysis of hemicellulosic extracts showed the presence of xylose as the major ose (54.7% from the crude cell wall and 46.7% from the delignified cell wall). Pectins were represented by homogalacturonan chains and rhamnogalacturonans 1. Data generated in this study are helpful for valorization of this plant.

The present study was carried out to investigate the antioxidant activity of the water and methanol extracts of leaves and fruits extracts of Chamaerops humilis L. by using ABTS cation radicals and cupric reducing antioxidant capacity (CUPRAC). Anticholinesterase effect of the extracts was tested against both AChE and BChE using a microplate-reader assay based on the Ellman method. The methanol extracts of C. humilis leaves contained relatively higher content of flavonoids and total phenolics than those of fruits. All the extracts were found to have different levels of antioxidant activity in the systems tested. The leave extract showed the highest value of antioxidant activity, based on ABTS radical-scavenging activity, while the fruit water extract showed the highest value (0.53±0.50 µg/mL) of cupric reducing antioxidant activity.  Our data indicates that both methanol and water fruit extract were active for BChE inhibition (31.65 ± 0.37 and 30.19 ± 0.56%) respectively, whereas, all leave extracts did not show any activity against BChE. The present study demonstrated that the methanol and water extracts fractions of C. humilis have different responses with different antioxidant methods. Our results suggest that the C. humilis could be used as a source of antioxidant agents and may be beneficial in the AD treatment.

No abstract

Studying the biometric characteristics of the stems of plant species has been of great interest to researchers in the wood and paper industry. The use of plant fibers has been widespread in the fields of composites, buildings, insulation, plastics and automobiles. The present study aimed to investigate the biometric characteristics of the stem fibers of local Algerian plant species, viz. Group 1 (Lygeum spartum and Stipa tenacissima), Group 2 (Linum usitatissimum in the greenhouse and Linum usitatissimum in natural conditions), Group 3 (Retama monosperma and Retama raetam) and Group 4 (Phoenix dactylifera and Ricinus communis). The extraction process was carried out using 1 M NaOH at 60 °C for 48 hours, and the fiber length was calculated for all the species using a micrometer. The fiber length of stems of all the species ranged from 0.36 to 5.18 mm. Then, the difference between each of the two species was approximated using Student's test. The results obtained showed that the t value ranged from 0.50 to 1.79 for Groups 4 and 1, respectively. There was no significant difference between them. These results suggest that these species are promising raw materials for paper production due to their adequate fibre length.

No abstract