2.5.1 - Extension curl in NGINX web server

I'm using NGINX web server for my platform 2.5.1+ because i needed install the BigBlueButton virtual classroom.

I can't use curl extension in my server.

If i try to run in my console

curl -v -o image_post_curl.png --data "mml=%3Cmath%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsup%3E%3Cmi%3Ex%3C%2Fmi%3E%3Cmn%3E4%3C%2Fmn%3E%3C%2Fmsup%3E%3C%2Fmath%3E&backgroundColor=%23fff"http://www.wiris.net/demo/editor/render

i obtain

sudo: curl: command not found

But phpinfo in my Moodle platform edits like in following image

I can't understand

Antonio