Valorization of Date Palm Wastes by Lignin Extraction to be Used for the Improvement of Polymeric Membrane Characteristics

This work aimed to valorize Date Palm Wastes (DPW) by the extraction of lignin and its application for polymeric membrane modification. Lignin was extracted from five types of DPW (date palm kernel, leaflet, pedicel, palm frond, and fibrilium) using the Klason method. Following DPW characterization, we remark the highest amount of extractives content in the leaflet sample (10.07 %) and the lowest in the fibrilium sample (6.51 %). The ash content ranged from 1.56 % for fibrilium to 7.96 % for palm frond. After extraction, the lignin yield was in the range of 22–32 %. The extracted lignins were characterized by Infrared and Ultraviolet–visible spectroscopy. All extracted lignins provide a high concentration of (-OH) group. Besides, both syringyl and guaiacyl are present in the extracted lignins with a slightly more syringyl unit. The extracted lignins were added to the polymeric solution, prepared from waste plastic, to produce membranes. These membranes showed improved hydrophilicity marked a decrease in the contact angle of 28 % when the lignin concentration increased from 0.125 to 0.5 %. In addition, the membrane porosity increased with the use of the extracted lignins as an additive

Fatty acids and triacylglycerols composition from Tunisian Acacia species seed oil

AbstractRecently, plant seeds that have not been enough explored and exploited are cheap sources of a lot of natural molecules for industrial applications. The aim of the present study was to evaluate for the first time the composition of fatty acids and triacylglycerols (TAG) of mature unexploited seeds of some Acacia species (Acacia cyclops, Acacia ligulata and Acacia salicina) harvested in Tunisia in order to reveal their potential for human consumption.Results showed that, Acacia seed oils were mainly unsaturated (more than 71%). The polyunsaturated fatty acids were the major fractions (52–68%) with the linoleic acid as the major fatty acid (more than 52%), followed by oleic acid (15–27%) as monounsaturated fatty acid. The TAG composition was significantly different among the three Acacia species. PLL, PLO, LnLO, OLL, OOL, and OOO were the major forms. Acacia seed oil could be used as potential source of oil with high industrial value; nevertheless in vivo tests are essential to confirm its safety before use

Analysis of agromorphological diversity of southern Tunisia faba bean (Vicia faba L.) germplasm

Forty two faba bean landraces (traditional farmers’ varieties) (Vicia faba L.) from southern Tunisia, belonging to 8 oasis agro-ecosystems were assessed using morphological descriptors. The studied descriptors focused on morpho-phenological and morpho-agronomical traits. The data obtained is extracted on the basis of 35 descriptors of 42 populations from 8 localities, at a rate of 30 replications (plants) per population, in totality of 1260 individuals. The data underwent an analysis of variance and a multivariate analysis. Significant differences among populations for the thirty five descriptors were observed. The multivariate analysis performed on averages of all parameters revealed eight main groups, and variation within the same oasis agro-ecosystems was extremely important. Particularly, the group of ‘Tozeur’ made up of five populations (P38, P39, P40, P41 and P42), and the group of ‘Medenine’ composed of seven populations (P19, P20, P21, P22, P23, P24 and P25) showed a special characters than the other populations especially for seedling characters. The geographical location did not seem to be the main factor structuring the variability of the studied landraces. There proved to be substantial phenotypic variability in the Tunisian faba bean germplasm.Keywords: Diversity analysis, germplasm, faba bean (Vicia faba L.), oasis agro-ecosystems, Southern Tunisi

Polysaccharides from Tossa jute (Corchorus olitorius L.) leaves: Extraction, antioxidant and antibacterial activities

The biological proprieties of mucilaginous polysaccharides (PSc) extracted from Tossa jute leaves (Corchorus olitorius  L.) using an ethanol precipitation method were studied. The results showed that PSc had higher total polyphenols and flavonoids and greater antioxidant activities. At 1.5 mg/ml PSc, the antioxidant activities were about 90% against 1,1-diphenyl-2-picryl hydrazyl radical (DPPH•) and 78% against lipid peroxidation. The PSc with a FRAP assay at the same concentration showed an effective protection against hydroxyl radicals and DNA breakage. Furthermore, the extracted PSc had a wide spectrum of antibacterial activities against all bacteria tested (Gram+ and Gram-). The overall data suggested that this natural PSc may be used as a competitive antioxidant and antimicrobial additive in food and in medicinal preparations

Effect of genotype and extraction method on polyphenols content, phenolic acids, and flavonoids of olive leaves (Olea europaea L. subsp. europaea)

Polyphenol’s extraction varied according to various factors. In this study, the effect of genotype and method of polyphenols extraction were investigated using leaves of two cultivated and two wild olive varieties and four hydromethanolic extraction methods. Quantitatively, significant differences were observed according to the extraction method, the genotype, and the interaction genotype-method of extraction. The heat reflux extraction showed the highest polyphenols content in wild olive leaves having an amount of 841.17 mg GAE/100 g DM. The qualitative phytochemical examination using high performance liquid chromatography (HPLC) of olive leaves showed some significant differences of phenolic compounds between genotypes. For the same oleaster genotype, the extraction method seemed to influence qualitatively the polyphenols profiles. The quinic acid was the dominant phenolic acid and the luteolin-7-O-glucoside was the major flavonoid observed in wild olive leaves having, respectively, 618.24 and 3211.44 mg/kg DM. The quinic acid has an amount of 400.15 and 275.39 mg/kg and the luteolin-7-O-glucoside has an amount of 2059.62 and 1214.49 mg/kg in cultivars leaves. The extraction by Soxhlet of wild olive leaves showed the highest quinic acid (1085.80 mg/kg DM) and luteolin-7-O-glucoside (3720.15 mg/kg DM) amounts. The hydromethanolic extraction assisted by Soxhlet of wild olive leaves constituted the optimal method to obtain high polyphenols contents enriched with phenolic acids and flavonoids

Essential oils, chemical composition, and biological activities of Eucalyptus oleosa F. Muell. : A review

Many Eucalyptus species are growing in the border of oasis areas. Eucalyptus sp. are generally known for their richness in essential oils and their virtues and economic interests. However, the great taxonomic diversity affects the quantity and quality of these oils. This study is designed to summarize the chemical composition of Eucalyptus oleosa and their biological activities. The yield of essential oils in the leaves of this species varies from 0.45% to 6.7%. These oils contain many chemical compounds of which 1,8-cineole is the main component (15.31% – 89.4%) followed by α-pinene (1%– 24.7%).  Eucalyptus oleosa essential oils exhibited antioxidant, antibacterial, anti-fungal and insecticidal activities with high variability. This variability is associated to many factors such as subspecific diversity, geographical location, part of plant and essential oil’s extraction method

Advances on antiviral activity of Morus spp. plant extracts: Human coronavirus and virus-related respiratory tract infections in the spotlight

(1) Background: Viral respiratory infections cause life-threatening diseases in millions of people worldwide every year. Human coronavirus and several picornaviruses are responsible for worldwide epidemic outbreaks, thus representing a heavy burden to their hosts. In the absence of specific treatments for human viral infections, natural products offer an alternative in terms of innovative drug therapies. (2) Methods: We analyzed the antiviral properties of the leaves and stem bark of the mulberry tree (Morus spp.). We compared the antiviral activity of Morus spp. on enveloped and nonenveloped viral pathogens, such as human coronavirus (HCoV 229E) and different members of the Picornaviridae family—human poliovirus 1, human parechovirus 1 and 3, and human echovirus 11. The antiviral activity of 12 water and water–alcohol plant extracts of the leaves and stem bark of three different species of mulberry—Morus alba var. alba, Morus alba var. rosa, and Morus rubra—were evaluated. We also evaluated the antiviral activities of kuwanon G against HCoV-229E. (3) Results: Our results showed that several extracts reduced the viral titer and cytopathogenic effects (CPE). Leaves’ water-alcohol extracts exhibited maximum antiviral activity on human coronavirus, while stem bark and leaves’ water and water-alcohol extracts were the most effective on picornaviruses. (4) Conclusions: The analysis of the antiviral activities of Morus spp. offer promising applications in antiviral strategies

In Vitro Antioxidant and Anti-Proliferation Activities of Polysaccharides from Various Extracts of Different Mushrooms

Polysaccharides were extracted from eight kinds of Chinese mushrooms using three solvents and were evaluated for their total carbohydrate, polyphenolic and protein contents, and antioxidant and anti-proliferation activities. The results suggested that all the polysaccharides had significant antioxidant capacities (EC50 ranged from 1.70 ± 0.42 to 65.98 ± 1.74 μM TE/g crude polysaccharide inhibition of ABTS+, EC50 ranged from 5.06 ± 0.12 to 127.38 ± 1.58 mg VCE/g CP scavenging of OH· and EC50 ranged from 0.70 ± 0.04 to 33.54 ± 0.49 mg VCE/g CP inhibition of lipid peroxidation) (TE: trolox equivalent; VCE: VC equivalent; CP: crude polysaccharide). The acid extracts of Russula vinosa Lindblad had the highest ABTS+ scavenging activity. Aqueous extracts of Dictyophora indusiata and Hohenbuehelia serotina possessed, respectively, the highest OH· scavenging capacity and ability to inhibit lipid peroxidation. Mushroom extracts also inhibited proliferation of HeLa and HepG2 cells in a dose-dependent manner. These results indicate that the mushroom polysaccharides might be potential antioxidant resources

Forage Potential of Non-Native Guinea Grass in North African Agroecosystems: Genetic, Agronomic, and Adaptive Traits

Guinea grass (Panicum maximum Jacq., renamed Megathyrsus maximus Jacq.) is a native forage plant in Africa of great economic value, but it was introduced in almost all tropical countries as a source of animal forage. Over the last decade, it was introduced in North arid regions of Africa (Morocco, Algeria, Tunisia, Libya, and Egypt) through authorized and unauthorized ways. It has two reproduction modes through sexual and apomictic ways. Besides its ability to provide high nutritive forage, guinea grass could affect the oases agroecosystems diversity due to its genetic aspects (apomixis and autotetraploidy) and eco-physiological traits (allelopathy effect and resistance to abiotic stress). That is why a review of genetic and eco-physiologic aspects of guinea grass is essential to investigate its potential introduction and management in new regions, particularly in arid and semiarid zones. In this paper, we review the most important traits of this plant that should be considered (polyploidy, apomixis, allelopathic effect, drought and salinity resistance, and invasion) for the potential success of guinea grass in integrated systems of forage/livestock