Loading images from AssetBundle

I am able to extract and instantiate a prefab from the asset bundle using the code below. But I wish to extract some png sprites from the asset bundle. Also I need to follow a hierarchy because I am loading those sprites onto gameobjects at runtime. After much searching on the internet, I couldn't find a solution. Any help? Thanks.

 using System;
 using UnityEngine;
 using System.Collections;
 
 public class CachingLoadExample : MonoBehaviour {
     public string BundleURL;
     public string AssetName;
     public int version;
     
     void Start() {
         StartCoroutine (DownloadAndCache());
     }
     
     IEnumerator DownloadAndCache (){
         // Wait for the Caching system to be ready
         while (!Caching.ready)
             yield return null;
         
         // Load the AssetBundle file from Cache if it exists with the same version or download and store it in the cache
         using(WWW www = WWW.LoadFromCacheOrDownload (BundleURL, version)){
             yield return www;
             if (www.error != null)
                 throw new Exception("WWW download had an error:" + www.error);
 
             AssetBundle bundle = www.assetBundle;
 
             if (AssetName == "")
                 Instantiate(bundle.mainAsset);
             else{
             GameObject go = (GameObject)Instantiate(bundle.LoadAsset(AssetName));
                 go.transform.SetParent(GameObject.Find("Canvas_Overlayed").transform);
                 go.GetComponent<assetbundleprefab>().init();
             }
             // Unload the AssetBundles compressed contents to conserve memory
             bundle.Unload(false);
             
         } // memory is freed from the web stream (www.Dispose() gets called implicitly)
     }
 }