How to use t() function with node_load in custom drupal module? I am using a custom module for my site, and I am using node_load to get the field value of type "long text" field and field of value of type "text".

Something like this 

$com_types = "".$ucom->node_title."";

How should I translate $ucom->node_title ?

t() function does not translate variables.

Thanks
Node translation should be done at the node level.  the t() function is for labeling elements of the interface and theme things. 

You should look at multi-language node translation modules,  this link is helpful

You'd first want to use something like this:  https://api.drupal.org/api/drupal/modules!translation!translation.module/function/translation_node_get_translations/7

It'll let you get the NIDs of the translated versions of the node you want,  then you can use node_load() to get the translated version.