In the course Fasting for Weight Loss, could a fruit smoothie take the place of fruit juicing using the ovary of a plant? Is there a big difference between these two?

there is a difference, not a huge difference but you can certainly use a fruit smoothie. Make it from whole fruit.

@Chris, Thank You for your feedback. I have also been struggling with my juicing and water fast. I believe it is because I am looking for fast results when I know it will take time.
I also refer to use fresh juice smoothie, I also drink once in day after my workout, sometimes if I out of food, I order my smoothie from using coupons from Reecoupons, because they have quite good deals and I easily get fresh smoothies without doing any effort, I hope it will also work for you.
Agree with the others about smoothies, they can be better