Acacia Senegal Research Articles

Comparative study on the effectiveness of gum arabic Acacia senegal and Moringa oleifera extracts on prevention of peptic ulcer in the experimental rats

Peptic ulcer is one of the world’s major gastrointestinal disorders and affecting 10% of the world population. An estimated 15000 deaths occur each year as a consequence of peptic ulcer. The cost of treatment for peptic ulcers is expensive and has side effects. So, it is necessary to conduct research to develop new therapeutic agents for the treatment of stomach ulcers. It is known that medicinal plants are important sources of biologically active molecules with the genetic ability of anti-ulcer. This study aims to evaluate the effectiveness of using gum arabic Acacia senegal and Moringa oleifera extracts on treatment of peptic ulcer in the experimental rats. Fifty rats were divided into 8 groups (6/each group). One group feeds the basic diet only (positive control group, G+). The remaining 44 rats were infected by aspirin solution to induce peptic ulcer in their stomach. One group of these rats feeds the basic diet only (negative control group, G-). Three groups G1, G2 and G3 feed on the basic diet + gum arabic extract (500, 1000 and 1500 mg/kg of rat weight). The other groups G4, G5, G6 feed the basic diet+ Moringa oleifera extract (800, 1000 and 1200 mg/kg of rat weight). At the end of the experiment (6 weeks), rats were fasted for 12 hours before slaughtering, blood samples were collected to obtain the serum, the stomach was separated for examination and gastric juice was collected to determine the (PH). The results indicated that rats in groups G6 and G3 had the highest increase in number of their WBC and in their HP as compared to (G+). Histological study revealed the absence of histopathological changes in G3 and G6 , while other groups showed mucosal vascular congestion and submucosal edema with inflammatory cell infiltration.

Temperature Effects on the Corrosion Inhibition of Mild Steel in Sulfuric Acid Solution by Acacia senegal Gum with Halide Ions

The effects of temperature on the inhibitive effect of naturally occurring Acacia senegal gum exudate on the corrosion of mild steel in sulfuric acid was studied between 35 and 70 °C using electrochemical impedance spectroscopy and potentiodynamic polarization methods. Findings showed that Acacia senegal gum exudate decreases the corrosion rate of mild steel. The inhibition efficiency declined with raising temperature above 35 °C. The increase in the corrosion rate with increasing temperature was observed for both uninhibited and inhibited systems. Addition of halide ions to the Acacia senegal gum exudate solution enhanced the corrosion inhibition efficiency because of synergistic effects, achieving higher performance with iodide ions as compared to bromide ions. However, the synergistic effects declined above 35 °C up to 70 °C due to temperature effects. It has been observed that increasing temperature adversely affected inhibition efficiencies of both Acacia senegal gum exudate and the synergy between Acacia senegal gum exudate and halide ions. Corrosion rates of mild steel, inhibition efficiencies of Acacia senegal gum exudate and the synergistic effects of halide ions from polarization and impedance measurements were consistent.
 Keywords: temperature, corrosion, mild steel, synergistic effects, Acacia senegal, gum exudate.

Influence of Drought on Acacia senegal (L.) Willd: Gum Yield within a Soil Moisture Gradient in North Eastern Nigeria


 
 
 There had been a discernible shift in climate affecting the Sahelian zone of northern Nigeria. This attribute of drought influenced the rate of gum Arabic production in the North eastern axis. Therefore, these called for the studied of the Influence of drought on Acacia senegal (L.) Willd. Gum yield within a Soil moisture gradient in north eastern Nigeria. Two studied areas were purposively selected based on the availability (Gujba and Nguru). Complete Randomised Design was employed with three (3) samples examined at six (6) levels in six different tapping periods. Also, systematic line transect of 1Km was laid at the middle of both plantations where 1m by 1m transect were further laid in four transect sample plots. The soil samples were collected with the aid of soil auger at different levels (0-25 cm, 25-50 cm, 50-75 cm, 75-100 cm, 100-150 cm, 150-200 cm). Data was subjected using analysis of variance with statistical analysis system and descriptive statistic was also employed. The results showed that mean yield of Gum Arabic is Gujba is higher than Nguru (45kg and 30kg) respectively. Furthermore, physiochemical properties showed that pH, aluminium calcium and magnesium in both plantations were very high which is harmful for plantation development. Therefore, there is need for proper conservation and silvicultural management for both study areas.
 
 

Acacia rigidula versus other Acacia taxa: An alarming issue in the European novel food regulation and food supplement industry

Based on the signals recorded in the RASFF (Rapid Alert System for Food and Feed), Acacia rigidula is a repeat- edly emerging unauthorized ingredient in weight loss dietary supplements in the European Union. Although the fruit, bark and gum of Acacia nilotica can be marketed as food supplement, and the gum of Acacia senegal as food ingredient, A. rigidula is an unauthorized novel food in the European Union. Here we present the first systematic overview of the phyto- chemical and pharmacological data reported on safety and efficacy of A. rigidula.

Extraction and Characterization of Fractionated Cellulose from Acacia Senegal

ABSTRACT The present study reports the extraction of cellulose from Acacia senegal by means of bleaching followed by alkali and acidic treatment. Isolated crude cellulose was further fractionated to obtain alpha (α) and beta (β) cellulose. The structural analysis was carried out by FTIR, CP-MASS 13C-NMR, and XRD. The morphology and thermal stability were investigated by SEM and TGA, respectively. The yield of cellulose (crude) in Acacia senegal was reported as 47%, while the content of α and β fractions of crude cellulose were 88.5% and 6.3% respectively. That suggests the predominant presence of α-cellulose in Acacia senegal. The FTIR data confirms cellulose extraction and also showed that alkali and acidic treatment successfully removed most of the hemicellulose and lignin from cellulose. Through XRD assessment, the crystallinity index of β-cellulose (82.09%) was found to be greater than α-cellulose (67.96%) and crude cellulose (75.70%). TGA demonstrated remarkably high thermal stability of β-cellulose with significantly low thermal decomposition i.e., 1.94% up to 640°C. The high thermal stability can create a new opportunity for Acacia cellulose to use it as an effective reinforcement for the preparation of biocomposites. The findings of this study would be helpful for further studies to know their possible applications.

Adaptation Trial and Growth Performance of Multipurpose Trees/Shrubs Species at Meti Site of Kellem Wollega Zone, Oromia, Ethiopia

This study was conducted at Meti Site of Haro Sabu Agricultural research center, Oromia. The objective of this study was to evaluate the adaptability and growth performance of different multipurpose trees/shrubs species and select or screen those best performed and adapted to the area. For this seedling of: Acacia senegal, Pinus patula, Callistemon citrinus, Olea africana and Spathodea nilotica were out planted on a plot of 14m*14m. The space between block of each species was 3m and Spacing between rows and within row was based on the recommendations of each species. In order to fit the given objectives growth parameter data of trees/shrubs (height, root collar diameter (only for trees< 1.3m in height), diameter at breast height (for trees ≥1.3m height) and survival rate) were collected by an interval of 6 months and Analyses of variance and LSD tests were employed to assess the results at p=0.05 using Minitab 17. As a result, the higher mean height growth was observed on Callistemon citrinus ( 2.59 m) , Spathoda nilotica ( 2.48 m) and Pinus patula ( 2.34 m). Again Gains in root collar diameter (RCD) was significantly highest on Pinus patula (37.75cm, 2.81cm) and Spathodea nilotica (32.08cm, 3.52cm).The Mean survivals of all trees grown at site were good ranging from 85.36% ( Pinus patula) to 100% ( Spathodea nilotica ( 100%). Generally this finding may help forest managers (stakeholder) to allocate species into the site that grow and adapt well. To select the most adaptable ones for such areas , use them at wider scale and increase their importance in the overall agricultural productivity (soil conservation, timber production, shading purpose, etc) and in general multifunction purposes in the area, further testing of provenances of the best performing species is recommended. Keywords: Growth performance, Meti, Relative growth rate in height (RGRH), Root collar diameter (RCD), Survival percentage. DOI: 10.7176/JEES/11-11-03 Publication date: November 30 th 2021

COMPLEMENTARY ANALYTICAL TECHNIQUES PAPER, THIN-LAYER, HIDE-POWER, AND COMBINED METHODS FOR CHARACTERIZATIONOF TANNIN IN PLANTS

The polyphenolic compoundsextract rich in gallo-catechol tannins submitted to complementary analytical techniqueswas evaluated. The whole plantspecies screened were of the condensed type except Acacia seyal var. fistuala, Acaciaseyal var. seyal, Casuarina equistifolia, and Pithecellobium dulcewere of mixedhydrolysable-condensed(gallo-catechol) type. The quantitative data indicated that 5 parts (bark) out of 12 species, when extracted, contained more than 10% tannins (oven-dry basis), the level of commercial interest. The catechin numbers indicated that all the studied species contained condensed tannin in varying amounts (0.6-45.7), while the presence of both gallic acid and catechin means that the tannin is of mixed type. Thin-layer and paper chromatography with different solvent systems confirmed the presence of catechin and gallic acid, and showed that tannic acid, fisetin, epicatechin and some unidentified phenolics were present. However, dihydrofisetin and robinetin, which were used as standards, were not detected. Astringency values shows that the Acacia mellifera(0.18), Acacia seyalvar.fistuala(0.18), Pithecellobium dulce (0.15), Acacia senegal (0.14), Acacia farnesiana (0.13), Calotropis procera (0.13)barks could be used in place of A. mearnsii(international commercial tannin materials) (0.16) because the degree of relative astringency or the ability of their tannin to combine with protein is close to that of A. mearnsii in other words these six species can give leather with characteristics comparable with that of A. mearnsii.

Gum Arabic Production and Population Status of Senegalia senegal (L.) Britton in Dryland Forests in South Omo Zone, Ethiopia

Senegalia senegal (L.) Britton is a multi-purpose dryland tree species that produces gum arabic, a commercially valuable product. However, this resource is underused in Ethiopian dryland areas. The aim of this study was to evaluate the population status and potential gum yield of S. senegal growing in natural stands in South Omo Zone, Ethiopia. Forty-five sample plots, each measuring 20 × 20 m, were established at 500 m intervals along transects, with 1 m2 subplots located within the main plots to determine regeneration. S. senegal trees with a diameter at breast height of between 2 and 12 cm were most prevalent. Forty-two tree species were associated with S. senegal, of which 16 were gum- and resin-producing species. S. senegal was positively associated with Vachellia tortilis, Senegalia mellifera, Vachellia nilotica, Commiphora edulis, and Dobera glabra. Senegalia senegal comprised approximately 35% of regenerating trees. The maximum gum arabic yield obtained was 3948 g tree−1. Linear models of dendrometric variables indicated that gum arabic yield is better predicted by tree diameter than by height. Despite the limitations of this pioneer survey, the population status and yield potential suggest that gum arabic could be sustainably produced and commercialized in natural stands of S. senegal in the studied dryland areas, providing local communities with supplementary seasonal incomes.

Biodiversity of woody species in the forest park of the Faculty of Agronomy of the Abdou Moumouni University in Niamey, Niger.

University forest parks can play a major role in conserving wood biodiversity. However, this woody biodiversity is still poorly understood. The objective of this study is to study plant biodiversity of the Faculty of Agronomy of the Abdou Moumouni University of Niamey (UAM) through the quantification of wealth, the specific composition and description of the population demographic structure of the settlement. The forest inventory was carried out on ten (10) 2500 m2 squares following a radiary transect. Diversity indices (Shannon, Piedlou and specific wealth), systematic composition (number of genders and families) were used for woody floristic analysis. The density, the distribution of woody according to the classes of diameter and height, the potential for regeneration were analyzed to assess the structure. Plenty-dominance character to appreciate the phytosociology of the stand. The study identified 1110 individuals representing 36 species belonging to 27 genee with 18 families. The Fabaceae (25%) is the most dominant family ( Tamarindus indica L. , Parkia biglobosa (Jacq) R. Br. ex G. Don. , Acacia Senegal (L) Willd , Bauhinia rufescence Lam , Faidherbia albida (Del.) A. Chev., Prosopis juliflora (Sw.) DC) in spaces of the Faculty of Agronomy of the University of Niamey with a dominance of Prosopis juliflora (Sw.) DCat more than 50%. The average density of woody plants is 444 ind/ha. Dominated by Calotropis procera (Ait.) Ait.f., (54 ind/ha) and Prosopis juliflora (Sw.) DC (224 ind/ha). Native species dominate the flora of the site. The structure is marked by the dominance of shrubs marked by Calotropis procera (Ait.) Ait.f., and Prosopis juliflora (Sw.) DCreflecting a rejuvenation of the woody stand. However, anthropogenic pressures and the absence of a policy for managing the faculty's spaces may be at the root of the reduction of this floristic diversity in the medium to long term. This is why actions (closure, monitoring) must be taken to safeguard this plant biodiversity.

Fiat Lux ... how Alessandro Volta illuminated his scripts

The ink used by Volta in his scripts appears to be a very complex mixture. Our analysis of the eluates from the EVA diskettes (via GCXGC/TOFMS) has revealed the presence of more than 1800 unique metabolites. The ink thus appears to be a very complex combination of different ingredients, mainly consisting of tannins, vegetable oils and resins together with root and wood dyes. In particular, the presence of hydroxy and dihydroxyanthraquinones, as well as natural quinoids, evidenced the use of madder dyes from Rubiaceae as an important component of this ink. Natural quinoids, based on a 9, 10-anthraquinone skeleton, hydroquinone and anthrone derivatives, and even the specific marker of alizarin, indicate the use of the Rubia tinctorum. Additionally, the presence of several signals of fatty acids, saturated and unsaturated mono and dicarboxylic acids, as well as of the typical signals of Pinaceae resins substantiated the use of a vegetable oil and colophony. Several signals of cyclic monosaccharides suggested also the use of natural gum (Acacia Senegal also known as Arabic gum). It is known that Arabic gum, as well as linseed oil, were often employed as thickeners to increase the viscosity of the ink and to protect it from excess absorption of atmospheric oxygen. Curiously, we also found characteristic signals from alkaloids such as Dioncophyllin A and B, typical metabolites from tropical/exotic plants such as Triphyophyllum, Habropeltatum and Dioncophyllum. To our reckoning such an extensive array of ingredients in inks adopted over millennia has never been reported.

Acacia senegal gum attenuates systemic toxicity in CCl4-intoxicated rats via regulation of the ROS/NF-\u03baB signaling pathway

Acacia senegal (AS) gum (Gum Arabic) is a natural emulsifier exudate from the branches and trunk of Acacia trees and it is recognized by the Food and Drug Administration (FDA) agency as a secure dietary fiber. The present research evaluated the systemic oxidative and necroinflammatory stress induced by CCl4 administration and the alleviating effect of AS gum aqueous extract (ASE, 7.5 g/Kg b.w.). The results demonstrated the presence of certain phenolic compounds in ASE, as well as its in vitro potent scavenging ability against ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), NO, and lipid peroxide radicals. Also, the outcomes revealed an improvement in the CCl4-induced liver, lung, brain, and spleen toxicity by reducing the levels of ROS, lipid peroxidation, NO, and the gene expression of NF-κB and its relevant ROS-mediated inflammatory genes. In contrast, the total antioxidant capacity (TAC), as well as the enzymatic and non-enzymatic antioxidants, were significantly upregulated in these organs after the treatment with ASE. These results were confirmed by improving the morphological features of each organ. Therefore, ASE can ameliorate the systemic toxicity caused by CCl4 via regulation of the ROS/NF-κB signaling pathway in the rat organs, which is owed to its phytochemical composition.

Assessment of Coffea Shade Value through Comparison of Mountainous Area with Farm Land Coverage, in Arsi Gololcha District, Oromia, Ethiopia

Coffea cultivation with shade tree is used for improving soil health, increasing coffea production, sustaining agro ecology. The study was attended in two kebele, on 36 farmers’ fields, at Gololcha district of East Arsi zone. The study was intended to assess the influence of coffea shade trees on farm lands versus mountainous area. Household interviews were used to get imperative separately, i.e. from old farmers, middle age farmers and young farmers. Significant difference value was observed between farm land and mountainous area coverage. Based on this respondents’ idea, before 25-30 years; the ‘condition of tree coverage at mountainous’ area in Arsi Gololcha district was ‘medium condition’ but not normal that means as deforestation of mountainous area have been starting before 30 years’ time; while the condition of tree coverage at farmland area also has been starting before 30 years’ time. The third respondents’ idea was interpreted with the real situation of the district, that it gave us a constructive inspiration on the role of coffea shade tree to enable the farm land to be taken as regular natural forest. The existing coffea shade trees are Cordia africana followed by Erythrina abyssinica and Acacia senegal. Farmers accounted 95% of coffea shade users and 4.6% without shade users. The respondents said that even if the rainfall intensity is increasing at farmland rather than mountainous area occasionally due to shade tree effect. On the contrary side, mountainous area exposed to deforestation since the farmers have been shifting to hilly side for their livelihood dependency.

Characterisation of briquettes from forest wastes: Optimisation approach

Waste from a forest environment constitutes an enormous quantity of renewable energy resources. In this study undesirable forest materials, such as jatropha seed shells (JSSs) and Eucalyptus camaldulensis wood shavings (EcWSs) were used in the production of briquettes with Acacia senegal as the binder using mixing proportions of 0 : 100, 25 : 75, 50 : 50, 75 : 25 and 100 : 0 while the binder was varied from 50, 60, 70, 80 to 90 g. Some physical properties, such as the density, moisture content, water resistance and shatter index, were optimised using the response surface methodology at these mixing proportions. The outcome of the production showed the briquettes to have mean values of 0.66 kg·m<sup>–3</sup>, 11.51, 91.12 and 99.7 % for the density, moisture content, water resistance and shatter index, respectively. The optimum mixing ratio and binder quantity of 75 : 25 and 60 g, respectively, would result in a briquette having a 0.70 kg·m<sup>–3</sup>, 10.88, 98.11 and 99.86% density, moisture content, water resistance and shatter index, respectively. It has been revealed that the JSS and EcWS are potential organic wastes which could be used as a feedstock for the production of briquettes. It could be concluded that the variation in the mixing proportion of the JSSs, EcWSs and A. senegal significantly affected the properties of the produced briquettes.

Correction to: Leaf morphology and stable isotope ratios of carbon and nitrogen in Acacia senegal (L.) Wild trees vary with climate at the geographic origin and ploidy level

Leaf morphology, total leaf nitrogen (N) content and carbon and nitrogen isotope ratios of Acacia senegal trees vary among ploidy levels and geographic origins. Leaf morphology was significantly correlated with carbon isotope composition (δ13C) among diploid trees, while a significant correlation was observed with nitrogen isotope composition (δ15N) among tetraploid trees. Leaf morphology and ploidy level can influence plants' ability to adapt to climatic conditions. Here we study Acacia senegal that has multiple ploidy levels and grows across a geographic range of mainly dry environments. We test if and how ploidy level and climate at the site of origin influence leaf shape and ratios of stable carbon and nitrogen isotopes of A. senegal. The study is based on leaves collected from 225 A. senegal trees representing 16 populations across the species range, grown in a common garden trial in Senegal. Leaf morphological parameters were measured, and ploidy level, total leaf nitrogen (N), carbon isotope ratios (δ13C) and nitrogen isotope ratios (δ15N) were determined. Three levels of ploidy were found, namely diploid, triploid and tetraploid, but at highly different frequencies among the 16 origins. Leaf morphology varied significantly among both geographic origins and ploidy levels, with especially triploid trees having distinct leaf shapes. Tetraploids displayed high δ13C and low δ15N values compared to diploids. For diploids, leaf length and number of leaflets were correlated with precipitation and latitude, respectively. Leaf morphology and isotopic discrimination in A. senegal vary according to ploidy level and geographic origin. Our analysis suggests that the differences likely reflect adaptation to different environments, but the patterns tend to differ between diploids and tetraploids.

Survival and growth of Acacia senegal (L.) Wild. (Senegalia senegal (L.) Britton) provenances depend on the rainfall at the site of origin

• Key message Variation among provenances of Acacia senegal (Senegalia senegal (L.) Britton) in their survival and growth in height and diameter at two sites in Senegal could be partly explained by the climate at their site of origin and also revealed genotype-by-environment interactions. Breeding programs and forest restoration projects should carefully select germplasm for optimal performance of this socioeconomically important tree species. • Context Several studies have shown important differences in adaptive properties among provenances (origins) of African savanna tree species, but there is a lack of studies on how these differences are expressed in different environments and age and to what extent they reflect local adaptation. • Aims This study investigates the survival and growth of trees from 15 African Acacia senegal (Senegalia senegal (L.) Britton) provenances tested in two environments and relates the differences among provenances to the climate at their site of origin and tree age. • Methods The study is based on 14 years growth in a common garden trial at two sites (Bambey and Dahra, Senegal) that differ in water availability, followed up by later assessment after 23 years at one of the sites. • Results The variation among provenances in survival, height, and diameter was significant, and differences could be partly explained by the climate at their site of origin. In general, provenances from dry sites survived better at both sites. However, we observed genotype-by-environmental interactions where provenances from dry sites on average performed relatively poorer in height and diameter at the wettest site (Bambey) compared to the drier site (Dahra), while the opposite was the case for provenances from wetter sites. • Conclusion The results support that divergent selection creates and maintains local adaptation of Acacia senegal provenances in relation to growth (height and diameter) and survival in areas with different water availability. This has important implications for choice of appropriate planting material for tree planting and for conservation of genetic variation among natural populations, but also for prediction of the effects of climate change.

Anthelminthic effects of extracts of indigenous browses from mid rift valley of Ethiopia

This study was conducted to evaluate the potential anthelminthic properties of extracts of leaves of indigenous browses (Acacia seyal, Acacia senegal, Acacia tortilis, Millettia ferruginea, and Vernonia amygadalina) based on three in vitro assays. Acetone extracts of browses at different concentrations (75 to 1200 μg/ml, for egg and larvae and 100mg/ml for an adult) were tested on three developmental stages of Haemonchus contortus (eggs, infective larvae, and adult worms) using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worm motility inhibition assay (AMIA). Significant effects were obtained with all five browses but differences were observed depending on the parasitic stages. The effects of five browse extracts on egg hatching were concentration-dependent, the highest (P<0.05) egg hatch inhibition rate was observed at 1200 μg/ml concentration for all browses. All extracts had a higher effect (P<0.01) than that of the negative control, phosphate buffer saline (PBS). In contrast, no concentration-response relationship was found for infective larvae and adult worms, although more potent effects were observed with the highest concentrations. The LMI rate (70%) induced by Vernonia amygadalina extract, at a concentration of 300 μg/ml, was the highest (P<0.05) of all other browses, even at higher concentrations. The highest LMI rate (62%) induced by Acacia senegal extract at higher concentration, was lower than that of LMI rate (70%) induced by Vernonia amygadalina, at 300 μg/ml concentration. Vernonia amygadalina was found to be highly and rapidly effective against adult worms inducing the highest mortality rate (90%) as soon as 4 hrs after incubation. Overall, the in vitro results suggest that these five browses do possess anti-parasitic properties and Vernonia amygadalina showed the most effective anti-parasitic property. These effects remain to be confirmed through in vivo study.

Sicklepod [Senna obtusifolia (L.) H. S. Irwin & Barneby] “Getting sleepy?”

Sicklepod [Senna obtusifolia (L.) H. S. Irwin & Barneby], also known as Cassia obtusifolia (L.), is an annual, herbaceous, dicotyledonous plant in the Fabaceae (Leguminosae) family, which is commonly known as the bean, legume, and pea family. The Fabaceae consist of herbs, shrubs, vines, or trees; the family has a cosmopolitan distribution with members numbering approximately 751 genera and 19,500 species (Christenhusz and Byng 2016). Characteristics of the Fabaceae include alternate, stipulate, and compound leaves. Leaflets often have pulvini (i.e., cushion-like swellings at the base of leaves that are subject to changes in turgor pressure), which are responsible for growth-independent or “sleep” movements. Another interesting anatomical feature exhibited by many species in the family is the formation of parenchymatous root nodules that are generated in association with nitrogen-fixing bacteria (Zomlefer 1994). The ovary of the Fabaceae usually develops into a dehiscent legume (e.g., pod). Although some Fabaceae may be weedy pests, others are important food crops [e.g., soybean, Glycine max (L.) Merr.] and fodder and forage plants (e.g., alfalfa, Medicago sativa L.). Some members of the Fabaceae produce valuable gums [e.g., gum arabic, Acacia senegal (L.) Britton] and dyes (e.g., indigo, Indigofera tinctoria L.), whereas others are prized as desirable ornamentals (e.g., eastern redbud, Cercis canadensis L.). Many species in the Fabaceae produce alkaloids or cyanogenic glycosides in different plant structures. Rotenone, an isoflavone insecticide, is derived from Derris eclipta (Wall.) Benth.

EFFECT OF SOWING DEPTH ON GERMINATION AND GROWTH OF GUM ARABIC (ACACIA SPECIES)

The study was carried out to determine the effect of sowing depth on the germination and growth of (Acacia species). The materials for the experiment consisted of top soil, river sand, cow dung and polythene bags. Polythene bags measuring 7.5 cm x 20 cm were filled with potting mixture consisting of top soil, river sand and cow dung in a ratio 2:2:1. The filled polythene bags were laid out in a randomized complete block design (RCBD) with each treatment having 25 polythene replicated four times. Two seeds were sown per pot at a depth of 1cm, 2cm, 3cm and 4cm, respectively, and were later thinned to one seeding per pot. It was observed that seed germination was faster with 1cm and 2cm sewing depth followed by 3cm while 4cm depth delayed seed germination. At 1 month after sowing (1MAS), seeds of (Acacia species) were statistically unaffected regardless of sowing depths. However, at 2, 3 and 4 months after sowing, seedling of (Acacia Seyal) significantly gave superior seedling height compared to (Senegalia Senegal). At 1, 2 and 3 MAS, Acacia species though statistically similar significantly increased seedling height and number of primary branches compared to 4cm sowing depth. Shallow sowing depths of 1 and 2cm of (Acacia species) seeds favored seed emergence and seedlings growth characters.

Leaf morphology and stable isotope ratios of carbon and nitrogen in Acacia senegal (L.) Wild trees vary with climate at the geographic origin and ploidy level

Leaf morphology and stable isotope ratios of carbon and nitrogen in Acacia senegal (L.) Wild trees vary with climate at the geographic origin and ploidy level

Adsorption Behavior of Arabinogalactan-Proteins (AGPs) from Acacia senegal Gum at a Solid-Liquid Interface.

Adsorption of five different hyperbranched arabinogalactan-protein (AGP) fractions from Acacia senegal gum was thoroughly studied at the solid-liquid interface using a quartz crystal microbalance with dissipation monitoring (QCM-D), surface plasmon resonance (SPR), and atomic force microscopy (AFM). The impact of the protein/sugar ratio, molecular weight, and aggregation state on the adsorption capacity was investigated by studying AGP fractions with different structural and biochemical features. Adsorption on a solid surface would be primarily driven by the protein moiety of the AGPs through hydrophobic forces and electrostatic interactions. Increasing ionic strength allows the decrease in electrostatic repulsions and, therefore, the formation of high-coverage films with aggregates on the surface. However, the maximum adsorption capacity was not reached by fractions with a higher protein content but by a fraction that contains an average protein quantity and presents a high content of high-molecular-weight AGPs. The results of this thorough study highlighted that the AGP surface adsorption process would depend not only on the protein moiety and high-molecular-weight AGP content but also on other parameters such as the structural accessibility of proteins, the molecular weight distribution, and the AGP flexibility, allowing structural rearrangements on the surface and spreading to form a viscoelastic film.