Advances in biotechnology of Emblica officinalis Gaertn. syn. Phyllanthus emblica L.: a nutraceuticals-rich fruit tree with multifaceted ethnomedicinal uses

Abstract

Emblica officinalis Gaertn. syn. Phyllanthus emblica L., universally known as 'Amla' or 'Aonla' or 'Indian gooseberry', is a popular fruit tree belonging to the family Euphorbiaceae and order Geraniales. It is said to be the very first tree that originated on earth, as claimed by age-old Indian mythology. Almost all parts of the tree i.e., root, bark, leaf, flower, fruit and seed are utilized in Ayurvedic and Unani medicinal formulations to improve the overall digestive process, decrease fever, act as a blood purifier, relieve asthma and cough, improve heart health, etc. This tree contains major secondary metabolites like emblicanin-A and emblicanin-B, and also is an affluent source of vitamin-C. Additionally, some other secondary metabolites like tannins, gallic acid, pyrogallol, and pectin are also present in significant amounts. Conventional propagation has been improved via suitable interventions of agrotechnology both in production and protection areas. However, the rate of propagation remains slower; therefore, attempts have been made for biotechnological advancements on E. officinalis. The present review makes an attempt to highlight the botanical description, geographical distribution, ethnopharmacological importance, conventional propagation and protection of this medicinal tree, describing the in vitro-based plant organ and tissue culture methods like direct and indirect organogenesis and somatic embryogenesis along with interventions of molecular marker-based biotechnology and nanotechnology. Further, the prospect of the yet-to-be-explored biotechnological methods for secondary metabolite enhancement like cell suspension, protoplast culture, genetic transformation, etc. and their potential for enhanced emblicanin production have also been discussed in this appraisal.

Keywords: Amla; Callus; Emblicanin; Micropropagation; Molecular markers; Nanoparticles; Somatic embryogenesis.

Fig. 1

Global distribution of Emblica officinalis Gaertn. syn. Phyllanthus emblica L. (Photograph is not in scale) (Source: unpublished photograph of Saikat Gantait)

Fig. 2

Salient botanical features of Emblica officinalis Gaertn. syn. Phyllanthus emblica L. a Full-grown trees in deciduous forest, b fruit-bearing trees with light grayish or greenish-brown barks, c arrangement of leaves and fruits along the branchlets of the tree, d almost sphere-shaped fruits showing minor conic indentation on both poles and six blurred perpendicular pole-to-pole stripes [Inset: top—edible fleshy yellowish-green mesocarp; left—endocarp in the form of hard stone encasing the seeds; center—crustaceous cocci, right—smooth, dark brown, and trigonous seeds] (Photographs are not in scale) (Source: unpublished photographs of Saikat Gantait)

Fig. 3

Some of the key phytochemicals found in different parts of Emblica officinalis Gaertn. syn. Phyllanthus emblica L. (Structure source: PubChem https://pubchem.ncbi.nlm.nih.gov) (Source: unpublished photograph of Saikat Gantait)

Fig. 4

Diagrammatic presentation of selected pharmacological properties of Emblica officinalis Gaertn. syn. Phyllanthus emblica L. (Source: unpublished photograph of Saikat Gantait)

Fig. 5

Diagram exhibiting the research areas that have been already studied and the areas that are yet to be explored regarding in vitro cell, tissue and organ culture of Emblica officinalis Gaertn. syn. Phyllanthus emblica L. (Source: unpublished photograph of Saikat Gantait)

Fig. 6

Diagram representing the green synthesis of metal/metal oxide nanoparticles from Emblica officinalis Gaertn. syn. Phyllanthus emblica L. extracts, their characterization and effects against microorganisms (Source: unpublished photograph of Sandeep Kumar Verma and Saikat Gantait)