Impact of Adjunctive Therapy with Chlorella vulgaris Extract on Antioxidant Status, Pulmonary Function, and Clinical Symptoms of Patients with Obstructive Pulmonary Diseases

This present trial investigated the efficacy of supplementation with Chlorella vulgaris, a bioactive microalga rich in macro- and micronutrients, in the improvement of biochemical and clinical symptoms in patients with obstructive pulmonary disorders. Ninety-seven patients with chronic obstructive pulmonary disease (COPD) or asthma who were under conventional treatment regimens were randomly assigned to C. vulgaris extract (CVE) (n=48; 2700 mg/day) or no adjunctive therapy (n=49) for eight weeks. Serum levels of antioxidants along with spirometric parameters and clinical symptoms were evaluated pre- and post-trial. The magnitude of increases in the concentrations of glutathione, vitamin E, and vitamin C, and activities of glutathione peroxidase, catalase, and superoxide dismutase enzymes were all significantly greater in the CVE vs. control group (p<0.05). In spite of increases, none of the assessed spirometric parameters (FVC, FEV1, FEV1/FVC, and FEF_25–75%) did significantly differ by the end of the trial in the study groups, apart from a significant elevation of FEV1 in the control group (p=0.03). The frequency of coughing, shortness of breath, wheezing, and sputum brought up were all significantly reduced in both CVE and control groups (p<0.05). The rate of improvement for sputum brought up and wheezing were significantly greater in the CVE group compared to the control group (p<0.05). Although CVE was found to ameliorate serum antioxidant status, its supplementation was not associated with any broncho-dilatory activity. The results of the present trial do not support any clinical efficacy for CVE in patients with obstructive pulmonary disorders.