Formulation and Evaluation of Evening Primrose Oil 500 Mg Soft Gelatin Capsules

Abstract

Evening primrose oil (EPO), extracted from the seeds of Oenothera biennis, is rich in polyunsaturated fatty acids, especially Linoleic Acid (LA) and gamma-linolenic acid (GLA). These fatty acids help produce anti-inflammatory compounds in the body. EPO is commonly used for conditions like rheumatoid arthritis, premenstrual syndrome, and various skin disorders. However, EPO is very sensitive to oxidation. This can lessen its effectiveness and lead to unstable byproducts that affect safety and taste. Formulating EPO poses challenges. To address this, the study focuses on creating 500 mg EPO soft gelatin capsules. These capsules protect the oil from air and light, maintaining its stability. The research includes formulation development, selecting suitable excipients like antioxidants, and optimizing ingredient combinations for consistent performance. It emphasizes the rotary-die encapsulation process, covering ribbon formation, fill weight control, seam quality, and drying behavior. A QbD framework was used to maintain consistent product quality by connecting critical material attributes (CMAs), critical process parameters (CPPs), and CQAs. The CQAs evaluated included GLA content, peroxide value, moisture content, disintegration time, leakage resistance, and shell strength. Stability testing was done according to ICH Q1A(R2) guidelines under various conditions, including high temperatures and humidity, as well as long-term storage. Results indicated that the formulation remained stable for up to 24 months. To further protect the product, packaging options like blister packs and nitrogen-filled containers were recommended.