The Gum Arabic in the southern region of Morocco

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Azzaoui & al. / Mor. J. Chem. 3 N°1 (2015) 99-107

99

The Gum Arabic in the southern region of Morocco

K. Azzaoui

^(a,b)*

, B. Hammouti

^(c)*

, A. Lamhamdi

^(a)

, E. Mejdoubi

^(a)

, M. Berrabah

^(a)

a

Laboratory of Mineral Solid and Analytical Chemistry LMSAC, Department of Chemistry, Faculty of Sciences, Mohamed 1st University, P.O. Box 717, Oujda 60000, Morocco

b

Chambre d’Artisanat de la Wilaya de Lâayoune- Boujdour, Lâayoune, Maroc

c

Laboratory LCAE-2.URAC18. Faculty of Sciences, Mohamed 1st University, Oujda 60000, Morocco

*Corresponding Author. E-mail: k.azzaoui@yahoo.com; Tel: (+212677042082) & hammouti@yahoo.fr , Tel : (+212668632273) Received 11 Oct 2014, Revised 27 Oct 2014, Accepted 16 Dec 2014

Abstract

: Gum arabic (GA) of the Marocco is a branched-chain, complex polysaccharide, either neutral

or slightly acidic, found as a mixed calcium, magnesium and potassium salt of a polysaccharide acid. The backbone is composed of 1,3-linked β - D- galactopyranosyl units. The side chains are composed of two to five 1,3- linked b- D- galactopyranosyl units, joined to the main chain by 1, 6- linkages. Gum acacia (GA) is used in pharmaceutical, cosmetic and food industries as an emulsifier and stabilizer, and in some countries in the traditional treatment of patients with chronic kidney disease (CKD). Different brands of GA are commercially available, but their comparative efficacy against adenine-induced CKD is unknown. The purpose of this study is to determine the écologic characteristics who assured the Acacia gum in the area of Morocco, its development and reproduction in an arid environment, as in our area.

Keywords: Gum Arabic, ecology, Pharmacological properties, application, Morocco.

1. Introduction

Gums have been used in diverse ways in the food industry as stabilizing and texture enhancing agents while improving the organoleptic quality of food. These properties of gums have been the main focus of research over the years. Gums are classified according to their source of extraction, chemical structure, and physical characteristics.

Gums are extractable from land plants (e.g. locust bean, guar, pectin) or marine plants (e.g. carrageenan, alginate), from microorganisms (e.g. xanthan, gellan, pullulan) or animal source (e.g. chitosan). Due to the presence of the hydroxyl group and their hydrophilic nature, gums are able to impact viscosity or gelling properties to their media [1].

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100 While the southern region of Morocco is the most unfavorable for the growth of living beings desert country, plants harbor flown as Acacia gum; thrive in a hostile environment. The Gum is Arabic cosmetible, dried, gummy exudate from the stems and branches of Acacia Morocco that is rich in non-viscous soluble fiber [2]. Gum Arabic (GA) is an edible, dried, gummy exudate of the stems and branches of Acacia AT Morocco that is rich in non-viscous soluble fiber. In 1982 JECFA classified GA as ‘ADI not specified’ [3]. However, as a result of subsequent research, the specifications for GA have been revised on several occasions [4-5]. GA has wide industrial uses as a stabilizer, thickening agent and emulsifier, mainly in the food industry (e.g. in soft drinks syrup, gummy candies and marshmallows), but also in the textile, pottery, lithography, cosmetics and pharmaceutical industries [6]. However, with further research, gums could be used as prebiotics to promote the quality of functional food through maintenance of viability and functionality of probiotics in food products [7]. It has a complex chemical composition (see below). In folk medicine, GA has been reported to be used internally for the treatment of inflammation of the intestinal mucosa, and externally to cover inflamed surfaces [8]. Despite the fact that GA is widely used as a vehicle for drugs in experimental physiological and pharmacological experiments, and is assumed to be an ‘‘inert” substance, some recent reports have claimed that GA possesses anti-oxidant and other effects [9]. Clinically, it has been tried in patients with chronic renal failure, and it was claimed that it helps reduce urea and creatinine plasma concentrations and reduces the need for dialysis from 3 to 2 times per week [10]. These findings are not universally accepted and their confirmation, validity, reliability and mode of action await further studies. The objectives of this study were therefore to (i) characterize the quality of Gum Arabic, Moroccan species in southern region (ii) Physical and chemical characteristics of Gum Arabic in the region, (iii) applications in everyday life.

Figure1. Photograph of the Gum Arabic

Gum Arabic has high water solubility, good emulsifying properties and relatively low viscosity, even in fairly concentrated solutions. As a ‘‘heterogeneous’’ material, within an oil-in-water system, the protein is likely to play a role in stabilising the dispersed phase, while the polysaccharides usually also impart stability by modifying the physical properties of the continuous phase. The molecular weight of A. Seyal gum is at least twice that of A. senegal.

However, the structure of A. seyal is similar to that of A. senegal, containing three main components, arabinogalactan (AG) with low protein content and low molecular weight, arabinogalactan protein complex (AGP) with high protein content and high molecular weight, and glycoprotein (GP) with both a higher protein content and higher overall molecular weight, respectively, when compared with A. Senegal. The Gum amino acids are distributed differently between the AGP and GP for ‘‘good’’ and ‘‘poor’’ gums [11]. The carbohydrate structure of the high molecular weight AGP component of A. seyal is also believed to be more ‘‘branched’’ than those observed in the A. senegal

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101 gum [12]. Protein inhibition refers to the delay in the overall crystallisation rate of a material due to the presence of proteins in it. Spray-drying carriers, such as Whey Protein Isolate (WPI) and Gum Arabic, are routinely utilised in the food and pharmaceutical industries, and it is generally believed that these carriers aid in the drying and stability of the product [13]. Commonly used protein additives in the production of powders in the food industries in- clude WPI, Gum Arabic and Casein. From the present state-of-the-art, it is well known that protein delays crystallisation, but it is unclear how and why this phenomenon occurs [14].

2. The ecology of Acacia Gum of Morocco

According to the High Commission for Water, Forests and the fight against desertification, species, of wide distribution, is present in both dry and arid Sahel and Sahara tropical bioclimate, but also in arid Mediterranean bioclimate and semi arid [15] (Figure 2) :

Figure 2. Area distribution of Acacia gum of Morocco [15]

2.1. Official Definitions

Gum Acacia, also known as Gum Arabic shown in Figure 3, is a natural gum harvested from the exterior of Acacia trees in the form of dry, hard nodules about 10-50 mm in diameter, and ranging from almost colorless to brown. Its unique properties endow it with a wide range of uses in food, beverage, confectionery, pharmaceutical, nutritional and

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102 industrial applications. The major source of Gum Acacia is the Sudan. Other important sources are Chad, Senegal and Nigeria [16].

Figure 3. Schematic representation of Arabic Gum

The chemical composition of GA is complex and numerous papers have been published on this subject (for example, the review of Islam et al., 1997 and papers cited therein) [17]. GA is a branched-chain, complex polysaccharide, either neutral or slightly acidic, found as a mixed calcium, magnesium and potassium salt of a polysaccharide acid (Arab Acid), shown in Figure 4. The backbone is composed of 1,3- linked β- D- galactopyranosyl units. The side chains are composed of two to five 1,3- linked β - D- galactopyranosyl units, joined to the main chain by 1,6-linkages.

Both the main and the side chains contain units of α- L- arabinofuranosyl, α- L- rhamnopyranosyl, β- D- glucopyranosyl and 4-O-methyl- β- D- glucopyranosyl, the last two mostly as end units [15]. Idris et al. (1998) reported GA to be comprised of 39– 42% galactose, 24– 27% arabinose, 12– 16% rhamnose, 15– 16% glucuronic acid, 1.5– 2.6% protein, 0.22– 0.39% nitrogen, and 12.5– 16.0% moisture. The chemical composition of GA can vary with its source, the age of the trees from which it was obtained, climatic condition and soil environment [18].

Figure 4. Structure chemic of the Acacia Gum.

Through the importance of acacia gum tree in the desert areas and semi-desert. Due to the role assigned to it by the High Commission for Water, Forests and the Fight against Desertification, to educate citizens about the importance of this plant local and continental, shown in Figure 5.

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103 Figure 5. Acacia forests Steering South Area Completed [15].

2.2. Pharmacological properties

2.2.1. GA as an anti-oxidant

The purported action of GA as an antioxidant has led to the publication of a series of articles by the same group claiming a protective effect of GA against experimental gentamicin and cisplatin nephrotoxicity [19], doxorubicin cardiotoxicity [20] in rats, and acetaminophen hepatotoxicity [21] in mice. All of these studies were based on the assumption that GA has strong anti-oxidant properties, and a major mechanism for the induction of these toxicities is the generation of free radicals [19]. However, Ali et al. (2003) reported that treatment of rats with GA produced only slight palliation of gentamicin nephrotoxicity, a result that does not confirm the work of Al-Majed et al. (2002).

2.2.2. Effect of GA on blood glucose concentration

Wadood et al. (1989) gave powdered seeds of Acacia Arabica orally to normal rabbits and rabbits with alloxan–

induced diabetes. It was found that the powder (at doses of 2, 3 and 4 mg/kg) significantly reduced the blood glucose concentration of normal, but not diabetic rabbits. The authors concluded, albeit without experimental evidence, that A.

Arabica initiated the release of insulin from pancreatic b cells of normal rabbits. Previously, experiments were carried out in vitro and in normal human subjects to evaluate alternative food-grade viscous polysaccharides as agents for reducing postprandial hyperglycemia and to assess the relationship between the in vitro and in vivo performance of the polysaccharides [22]. Mixtures of different types of gum (not including GA) have been shown to inhibit glucose movement in vitro, and lower postprandial blood glucose and plasma insulin in human subjects when incorporated in a drink containing 50 g glucose. Infusion of meals containing starch showed that a decrease in the digestion rate of starch in the upper small intestine accounted for part of the effect of viscosity on glycemic response, whereas the main effect of gum was apparently to slow gastric emptying [22].

3. Application

Gum Arabic is used in many industrial applications including the food industry. However, due to stringent regulations imposed on all food additives, Gum Arabic is subject to a quality and toxicological checks countries, organizations

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104 and users. To comply with these requirements and to enter the market for Gum Arabic trade must meet certain chemical specifications.

3.1. Emulsions & Beverages

Gum Arabic is recognized as a key ingredient in the industrial production of beverages. Its emulsifying, stabilizing and suspending ability are providing key advantages for the production of emulsions and beverages. It is used for encapsulation of flavor essential oils, vitamins, aromatic compositions, plant essences etc. The low calorie and high- fibre content of Gum Arabic makes it the first choice for functional beverages, diet products and other drinks with nutritional claims. In oil in water or water-in-oil systems, Gum Arabic is coating the fat or oil droplets, providing excellent flavor retention, stability and shelf, homogeneous texture and a pleasant mouthfeel.

3.2. Nutraceutical products

Gum Arabic is used in a wide range of food and nutritional applications to provide dietary fiber and additional benefits such as moisture management and extended shelf life. Guaranteed to contain a minimum of 90% soluble dietary fiber, Gum Arabic can be used in tablets, nutrition bars, beverages, juices, baked goods, and most any application where additional fiber is required [22].

3.3. Dietetic & Diabetic products

Gum Arabic is often used as a source of soluble fiber in low calorie and dietetic beverages. Gum Arabic is used for dietetic and diabetic products such as reduced sugar and sugarless candies and other confectionery. It is replacing very well the bulk and texture of sugars in combination with other sweeteners and it is providing binding and fiber in low calorie products. It seems to be the perfect solution for reduced-fat ice cream and dairy desserts: it is replacing the fat content but preserving the creaminess of the products [22].

3.4. Pharmaceuticals

In pharmaceutical industry Gum Arabic as a natural ingredient is used for emulsification, stabilization and binding as well as other functions like: suspending agent, demulcent action, film forming, encapsulation [22]. In medicated cough drops it is used as a main ingredient, preventing sugar crystallization and giving good texture to the drops. Used in syrups as a suspending agent and demulcent, it contributes to the stability of the end-product. Its adhesive properties make it a good choice for compressed tablets and coating of pills. Gum Arabic is also used for encapsulation of oil- soluble vitamin sin powder form, giving an increased resistance to oxidation.

3.5. Cosmetics

The cosmetic industry is using gum Arabic for a large range of functionalities: stabilizer, viscosity agent, film former, emulsifier, binding agent [15]. Gum Arabic is used in creams, lotions, mascaras and cake cosmetics as a protective colloid.

3.6. Industrial applications

 Lithography: Gum Arabic is used as a sensitizer for lithographic plates as an element in the light sensitive composition and as an ingredient of the fountain solution [15].

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105

 Inks, Water Paints and Pastels: Gum Arabic is an important constituent of many special purpose inks. Water color and quick drying inks utilize the suspending and binding properties of Gum Arabic.

 Ceramics and Porcelain: Gum Arabic is used as a glaze thickener.

 Firework and Explosives: Gum Arabic is used as a binding, adhesive agent.

 Pesticide and Insecticide: Gum Arabic is used as a suspending agent.

 Stamps and Cigarette papers: its adhesive capability is used to form a transparent adhesive film.

 Photography: The historical photography process of gum bichromate photography uses Gum Arabic mixed with ammonium or potassium dichromate and pigment to create a colored photographic emulsion that becomes relatively insoluble in water upon exposure to ultraviolet light. In the final print, the acacia gum permanently binds the pigments onto the paper.

 Shoe polish: today, shoe polish is usually made from a mix of natural and synthetic materials, including Gum Arabic as natural ingredient.

 Detergent: Gum Arabic is used as surface-active additive for removing oil.

 Textiles: Gum Arabic gives body in finishing silk and rayon fabric without loss of transparency. It is also used as a sizing and finishing agent in printing formulations for imparting designs or decorations.

3.7. Craft

The wood used for the production of art objects (Table 1).

Table1. Different uses of Gum Arabic

Use Sectors Gum Arabic Applications

Food Sector

Confectionery Tabletting, Coating, Chewing Gum, Chewing gum.

Aromatic beverage Soda, Syrup, Beverage, Stabilization,

Aromatics Powder flavors, disturbing powder, instant drinks

Products food Coating of dry fruits, sauces, condiments, frosting cookies, cakes, desserts.

pharmaceutical sector

Pharmacy Pasta pectoral powdered vitamins, Pills, capsules, syrups various sector

glues Office glue, Stamps, Envelope, Gummed paper Cosmetic liquid soap and lotions

Various Various foundry, Ceramic, Pyrotechnics, insecticides, pesticides, textile industry

3.8. Problems and constraints related to the Acacia trees

 Succession of years of drought and climate change;

 Pressuring the human through the pieces of the unjust party static and overgrazing, which reduces the chances of seed germination and growth of shrubs;

 Lack of production of fruits and seeds infertility in some cases resulting in little or no natural abandonment;

 Few studies and scientific research and the scarcity of references [11].

4. Gum Arabic of African continent

International specification identifies Gum Arabic as a dried exudate obtained from the stems and branches of Acacia Senegal (L.) Willd. Or Acacia Seyal. The vast majority of Gum Arabic that enters international trade originates from

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106 an area described as ‘gum belt’ in Sub-Saharan Africa This belt extends from the northern parts of West Africa eastwards to Sudan, Ethiopia, Eritrea and Somalia [23]. The quality of Gum Arbic is affected by botanical origin, individual tree differences, environmental factors such as climatic and soil conditions, and harvest and post-harvest handlings. It is obvious that gums from different species (A. Senegal and A. Seyal) exhibited characteristics that are intrinsically different. Even within the same species, different varieties and individuals of different provenances produce gum with different characteristics. Recognizing these differences in the species, varieties and environment is important in producing Gum Arabic for a desired end use [24]. Senegal is one of the conspicuous indigenous species in the vegetation of the Rift Valley of Ethiopia. However, Ethiopia is one of the Gum Arabic producer and exporter countries to the world market [25]. Despite the abundant natural occurrence of A. Senegal in most woodland vegetations of the country, no studies have assessed the quality of Gum Arabic produced in the country. Generally, the potentials that gum production offers for dry land development of the country received little attention [25]. Gum Arabic (Acacia species) is the exudates obtained from the various species of the genus Acacia. There are about 1100 spp distributed over tropical and sub-tropical areas of Africa, India, Australia and America. However, only Acacia Senegal (grade 1) and Acacia seyal (grade 2) yield Gum of economic significance [26]. The optimum conditions for the growth and performance of the plant are excessive heat, high elevation and sandy soil with scarcity of moisture [27]. Production of Gum Arabic in Nigeria is largely from the wild except in Borno, Jigawa and Yobe State where plantations of several hectares were established. Gum Arabic production is exclusively from gum bearing trees and local producers are typically peasant farmers picking gum exudates as a secondary or complementary source of revenue [27].

The commercial use of Gum Arabic can be traced back to the year 2000 BC, when the Egyptians used it in foods, adhesive and paint industries [28]. Presently, Nigeria is second to Sudan in the world production of Gum Arabic. The world production of Gum Arabic and contribution by countries. That is, the better the market situation of a crop, the more the desire for higher production among farmers. Odo and Oleghe (1998) reported a diversity of users of Gum Arabic in the areas of food, and beverage industries, pharmaceuticals, printing and cosmetic industries. Production of Gum Arabic in Nigeria is largely from the wild [26]. However, many efforts are made in the Gum Arabic growing states in the country to establish Gum Arabic plantation on a large scale. The demand for Gum Arabic is on the increase worldwide. Of course, the major determinant of the production of any industrial crop is its demand and the revenue derivable from it.

5. Conclusion

An Acacia system represents a form of adaptation and coping with ecological data to the hard desert areas and thus is of particular importance to the southern areas. Is a balanced system in their environment as there was not threatened by external factors. An effective tool to combat desertification and restore normal life in the desert communities.

It’s Can be considered as a lever for the development of desert areas in view of the multiple advantages, and here shall be valued and developed in the medical field because GA is a non-digestible food ingredient that has found many applications in the food and pharmaceutical industries. The gums claimed therapeutic usefulness in hepatic and renal failure awaits further verification in animal models and humans. No significant adverse or toxic actions have been associated with the use of GA.

Acknowledgements- The authors present their thanks to Mr. M. Abderahman Sniba, Président of the craft room of Laayoune, and Mr. A. Dahi, Regional Director of craft - Laayoune.

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