**1. Introduction**

The use of Synthetic polymers as drug carriers is common nowadays. They do have several advantages, yet there are noticeable disadvantages, including poor adaptation to the patient's body, high cost, and also causing acute and chronic side effects, for example poly-(methyl methacrylate) (PMMA) can cause skin and eye irritation. Other disadvantages of synthetic polymers utilized in tissue engineering include low biocompatibility, the release of acidic products during degradation that may cause systemic and native reactions, and rapid loss of mechanical strength [1].

The use of plant gum nanoparticles as drug carriers is one of the several ways that is employed greatly for the treatment of infections and various illnesses like cancer and this has been stated in various researches [2].

Plant gums are the native gum-producing trees, growing freely within the country's forests, and represent abundantly available materials. Plant-derived gums consist of polysaccharides and a few of them are applied medicinally for several years, including gum Tragacanth which has been used since third century B.C. Various studies have shown the advantage of using Green chemistry-based drug carriers for various purposes compared with using synthetic and chemical substances. Plant gum

## **Figure 1.**

*The images related to the four famous plant gums: gum Tragacanth, gum Arabic, Gum Ghatti, gum Karaya.*

drug carriers can have advantages in the pharmaceutical industry including being biodegradable, biocompatible, nontoxic, providing better tolerance to the patient, and having fewer side effects. They also do not cause allergies in humans, do not irritate the skin or eyes, and have low production costs [3]. The extensive use of antibiotics has led to serious issues including resistance toward multiple antibiotics. Now there are articles showing that the use of plant gum nanoparticles loaded with drugs was successful in the treatment of multi-drug resistant bacteria including MRSA,1 VRE,2 and MDR-GNB3 [4, 5].

Natural gums constitute a structurally diverse class of biological macromolecules with a broad range of physicochemical properties, therefore they can be loaded with various drugs and can have a multi-target therapeutic effect. In this case, there will not be the need for consuming several drugs for the treatment of systemic disease.

That being said, the use of plant gums is limited due to a series of disadvantages. They may have microbial contamination because of the moisture in their content. Also, in storage, their viscosity decreases due to contact with water. This situation can be handled by creating nanoparticles from these plant gums and then using them as drug carriers. Green chemistry-based NPs4 are often applied for designing and manufacturing products by applying sustainable materials which may eliminate or reduce the appliance and formation of unsafe and toxic substances. In this regard, plant gum polysaccharides and their nanostructures are often applied as drug carriers. Natural nanoparticles, improve the stability and bioavailability, as well as the biological distribution of natural products,

<sup>1</sup> Methicillin-resistant *Staphylococcus aureus*.

<sup>2</sup> Vancomycin-Resistant Enterococci.

<sup>3</sup> Multidrug-resistant Gram-negative bacteria.

<sup>4</sup> Nano-particles.
