Antimicrobial and anti-tumor activities of endophytes from Lycium barbarum of Ningxia / 中国中药杂志

The antimicrobial activity and cytotoxicity in vitro of the fermentation broth of 10 endophytic strains isolated from Lycium barbarum were determined to screen high activity endophytic strains. Sequences analysis of ITS and 16S rDNA was used for molecular identification of the strains. The results showed that 5 endophytic fungi had no inhibitory activity against the tested pathogens. Endophytic actinomycete strain AL6 had a certain inhibitory effect on 3 kinds of pathogenic fungi, and strain AL5 only had strong inhibitory activity against Staphylococcus aureus. However, the anti-tumor activity of endophytic fungi was significantly higher than that of actinomycetes. Four endophytic fungi strains exhibited the growth inhibition rate of above 50% against at least one of the tested tumor cells when the concentration of fermentation broth was 0.2 g•L⁻¹. Sequences analysis showed that 5 endophytic fungi strains belonged to genus Aspergillus, Penicillium and Emericella, and the 5 endophytic actinomycetes strains belonged to genus Aspergillus, Penicillium and Emericella. Aspergillus strain FL1 had stronger inhibitory activity against A549 and HeLa cells, and the IC₅₀ values were 0.022，0.028 g•L⁻¹, respectively, which was worthy of further study.

Screening and identification of antioxidant endophytes from Lycium barbarum of Ningxia / 中国中药杂志

In this paper, 29 endophytes were isolated from different organs and tissues of Lycium barbarum of Ningxia by tablet coating method, 18 of them was fungi, and 11 of them was actinomycetes. The endophytes quantity in the different tissues were leaves > flowers > roots >fruits; The hydroxyl radical scavenging activities of 11 endophytes were investigated by Fenton reaction, and total antioxidant capacities of them were examined by a. total antioxidant capacity test kit; culture features and strain-specific sequence analysis were employed to explore the diversity of the 11 endophytes. The result showed that 5 fungi and 6 actinomycetes that having antioxidant activity could be phylogenetically classified into 3 genera, 3 genera and 3 families, respectively. The total antioxidant capacity and hydroxyl radical scavenging activity of the 11 endophytes showed distinct difference. The antioxidant activity of Aspergillus were stronger, among which total antioxidant capacity of fL1 was (188.5 ± 0.549) U · mL⁻¹ and the IC₅₀ was 0.3 mg · L⁻¹; the IC₅₀ of strain fL1 was 0.42 mg · L⁻¹ and the total antioxidant capacity of fL9 was (113.63 ± 1.021) U · mL⁻¹, all of them were stronger than the positive control Vit C. The experimental results indicated that endophytic fungi of L. barbarum of Ningxia have a great developing and application prospect for the development of antioxidant agent.