The global market for nutritional supplements (NS) is growing rapidly, and the use of L-arginine (Arg), L-citrulline (Cit), and citrulline malate (CitMal) supplements has been shown to enhance cardiovascular health and athletic performance. Over the past decade, Arg, Cit, and CitMal supplements have received considerable attention from researchers in the field of exercise nutrition, who have investigated their potential effects on hemodynamic function, endothelial function, aerobic and anaerobic capacity, strength, power, and endurance. Previous studies were reviewed to determine the potential impact of Arg, Cit, and CitMal supplements on cardiovascular health and exercise performance. By synthesizing the existing literature, the study aimed to provide insight into the possible uses and limitations of these supplements for these purposes. The results showed that both recreational and trained athletes did not see improved physical performance or increased nitric oxide (NO) synthesis with 0.075 g or 6 g doses of Arg supplement per body weight. However, 2.4 to 6 g of Cit per day for 7 to 16 days of various NSs had a positive impact, increasing NO synthesis, enhancing athletic performance indicators, and reducing feelings of exertion. The effects of an 8 g acute dose of CitMal supplement were inconsistent, and more research is needed to determine its impact on muscle endurance performance. Based on the positive effects reported in previous studies, further testing is warranted in various populations that may benefit from nutritional supplements, including aerobic and anaerobic athletes, resistance-trained individuals, elderly people, and clinical populations, to determine the impact of different doses, timing of ingestion, and long-term and acute effects of Arg, Cit, and CitMal supplements on cardiovascular health and athletic performance.

Black ginseng (BG, CJ EnerG), prepared via nine repeated cycles of steaming and drying of fresh ginseng, contains more accessible acid polysaccharides and smaller and less polar ginsenosides than red ginseng (RG) processed only once. Because RG exhibits the ability to increase host protection against viral respiratory infections, we investigated the antiviral effects of BG. Mice were orally administered either BG or RG extract at 10 mg/kg bw daily for two weeks. Mice were then infected with a A(H1N1) pdm09 (A/California/04/2009) virus and fed extracts for an additional week. Untreated, infected mice were assigned to either the negative control, without treatments, or the positive control, treated with Tamiflu. Infected mice were monitored for 14 days to determine the survival rate. Lung tissues were evaluated for virus titer and by histological analyses. Cytokine levels were measured in bronchoalveolar lavage fluid. Mice treated with BG displayed a 100% survival rate against infection, while mice treated with RG had a 50% survival rate. Further, mice treated with BG had fewer accumulated inflammatory cells in bronchioles following viral infection than did mice treated with RG. BG also enhanced the levels of GM-CSF and IL-10 during the early and late stages of infection, respectively, compared to RG. Thus, BG may be useful as an alternative antiviral adjuvant to modulate immune responses to influenza A virus.

Sehee Lee · Soo-yeon Park · Kyeong Jin Kim · Sonwoo Kim · Yanghoon P. Jung · Ji Yeon Kim. JABC 2023;66:114-21. https://doi.org/10.3839/jabc.2023.017