Natural Factors Celery Seed Extract - 80% 3nB - Modern research is upholding the traditional medicinal value of the common celery plant, and scientific findings show that celery contains a powerful healing factor compound known as 3nB (3-n-butylphthalide). 3nB appears to help lower blood pressure by acting as a diuretic and vasodilator through impacting the production of prostaglandin.