Central Department of Biotechnology, Tribhuvan University, Kirtipur, Nepal.
Department of Applied Microbiology and Food Technology, Research Institute for Bioscience and Biotechnology (RIBB), Kathmandu, Nepal.
Pharm Biol. 2021 Dec;59(1):933-936. doi: 10.1080/13880209.2021.1946091.
species are prolific sources of bioactive secondary metabolites known especially for their antimicrobial and anticancer activities.
This study sought to isolate and characterize antioxidant molecules biosynthesized by sp. KTM18. The antioxidant potential of an isolated compound and its toxicity were accessed.
The compound was purified using bioassay-guided chromatography techniques. Nuclear magnetic resonance (NMR) experiments were carried out for structure elucidation. The antioxidant potential of the isolated compound was determined using DPPH free radical scavenging assay. The toxicity of the isolated compound was measured using a brine shrimp lethality (BSL) assay.
Ethyl acetate extract of sp. KTM18 showed more than 90% inhibition of DPPH free radical at 50 µg/mL of the test concentration. These data were the strongest among 13 isolates (KTM12-KTM24). The active molecule was isolated and characterized as maculosin (molecular formula, CHNO as determined by the [M + H] peak at 261.1259). The DPPH free radical scavenging activity of pure maculosin was higher (IC, 2.16 ± 0.05 µg/mL) than that of commercial butylated hydroxyanisole (BHA) (IC, 4.8 ± 0.05 µg/mL). No toxicity was observed for maculosin (LD, <128 µg/mL) in brine shrimp lethality assay (BSLA) up to the compound's antioxidant activity (IC) concentration range. The commercial standard, berberine chloride, showed toxicity in BSLA with an LD value of 8.63 ± 0.15 µg/mL.
Maculosin may be a leading drug candidate in various cosmetic and therapeutic applications owing to its strong antioxidant and non-toxic properties.
物种是生物活性次生代谢产物的丰富来源，尤其因其抗菌和抗癌活性而闻名。
本研究旨在分离和表征 sp. KTM18 生物合成的抗氧化分子。评估了分离化合物的抗氧化潜力及其毒性。
使用生物测定指导的色谱技术对化合物进行纯化。通过核磁共振（NMR）实验进行结构解析。使用 DPPH 自由基清除测定法测定分离化合物的抗氧化潜力。使用盐水虾致死（BSL）测定法测量分离化合物的毒性。
sp. KTM18 的乙酸乙酯提取物在 50μg/mL 的测试浓度下对 DPPH 自由基的抑制率超过 90%。这些数据是在 13 种分离物（KTM12-KTM24）中最强的。活性分子被分离并鉴定为疣状素（分子公式，CHNO，由 [M+H] 峰在 261.1259 处确定）。纯疣状素的 DPPH 自由基清除活性（IC，2.16±0.05μg/mL）高于商业丁基羟基茴香醚（BHA）（IC，4.8±0.05μg/mL）。在盐水虾致死试验（BSLA）中，疣状素（LD，<128μg/mL）没有表现出毒性，直到化合物的抗氧化活性（IC）浓度范围。商业标准盐酸小檗碱在 BSLA 中表现出毒性，LD 值为 8.63±0.15μg/mL。
由于疣状素具有强大的抗氧化和无毒特性，因此可能成为各种化妆品和治疗应用的候选药物。
