Chlorella vulgaris, a coccoid green eukaryotic microalga, is a popular food supplement and has been marketed as a nutritional supplement in Asia. Despite numerous reports on the antioxidant property of this species, its toxic effect has not been extensively studied. The aim of this study was to determine the acute oral toxic effect of C. vulgaris on female Sprague Dawley (SD) rats. An acute oral toxicity assessment of C. vulgaris was performed based on the Organization for Economic Cooperation and Development (OECD) Guideline 420. These guidelines are divided into a sighting study and a main study. In the sighting study, C. vulgaris extract was administered orally in sequential doses of 5, 50, 300 and 2000 mg kg⁻¹ body weight (BW) with one rat used for each dosage. Clinical observation and mortality were observed for each rat to monitor signs of toxicity for 14 days. BW and relative organ weight (ROW) were recorded. Blood was collected for liver function test (LFT). Gross pathological evaluations were performed after euthanasia of rats. Haematoxylin and eosin (H&E) staining of the liver and kidney was also performed. The main study was performed based on the highest dose in the sighting study that did not exhibit any signs of toxicity and mortality. For 14 days, clinical observations, BW, and ROW were recorded. Blood from rats in the main study was also measured for LFT, and gross pathological evaluations and H&E staining of the liver and kidney were also performed. The highest dose of 2000 mg kg⁻¹ BW C. vulgaris was used in the main study. No toxicity and mortality were observed in both the sighting study and the main study. Increases in BW were observed in both studies. Gross pathological evaluations showed no signs of organ abnormalities on each organ in the sighting and main studies. The ROW also showed no differences. The values of biochemical parameters in the liver function test showed no differences in the sighting study. However, in the main study, significant decreases in alkaline phosphatase (ALP) and aspartate aminotransferase (AST) were observed on day 14 compared with day 0 (p < 0.05). Chlorella vulgaris showed no toxicity at the dose of 2000 mg kg⁻¹ BW. In conclusion, C. vulgaris can be categorized as unclassified according to the Globally Harmonised Classification System (GHS) for chemical substances and mixtures.

小球藻，一种球状绿色真核微藻，是一种受欢迎的食品补品，在亚洲已作为营养补品销售。尽管有许多关于该物种抗氧化特性的报道，但其毒性作用尚未得到广泛研究。这项研究的目的是确定寻常梭状芽胞杆菌对雌性Sprague Dawley（SD）大鼠的急性口服毒性作用。根据经济合作与发展组织（OECD）准则420，对寻常小球藻进行了急性口腔毒性评估。这些准则分为目视研究和主要研究。在目击研究中，寻常果提取物以5、50、300和2000 mg kg ^-1的连续剂量口服给药体重（BW），每种剂量用一只大鼠。观察每只大鼠的临床观察和死亡率，以监测毒性迹象14天。记录体重和相对器官重量（ROW）。收集血液用于肝功能测试（LFT）。对大鼠安乐死后进行总体病理评估。还对肝脏和肾脏进行了苏木精和曙红（H＆E）染色。主要研究是根据目击研究中的最高剂量进行的，未显示任何毒性和死亡率迹象。在14天内，记录了临床观察，体重和ROW。还对主要研究中大鼠的血液进行了LFT测量，还对肝脏和肾脏进行了总体病理评估和H＆E染色。最高剂量2000 mg kg ^-1 BW主要研究使用寻常梭状芽胞杆菌。在观察研究和主要研究中均未观察到毒性和死亡率。在两项研究中均观察到体重增加。总体病理评估显示，在观察和主要研究中没有发现每个器官的器官异常迹象。ROW也没有显示差异。肝功能检查中的生化参数值在观察研究中无差异。但是，在主要研究中，与第0天相比，第14天观察到碱性磷酸酶（ALP）和天冬氨酸转氨酶（AST）显着下降（p  <0.05）。小球藻在2000 mg kg ^-1 BW剂量下无毒性。总之，普通寻常梭状芽胞杆菌 可以根据化学物质和混合物的全球统一分类系统（GHS）归类为未分类。