Thermo nanodrop 2000 uv microspectrophotometer

Intestinal contents of rats in the CON, MOD, and GO‐H groups were characterized by 16S rRNA gene sequencing. The method was based on our previous research (Jiang et al.,  2020 (link)). The total DNA was examined by Thermo Nanodrop 2000 UV microspectrophotometer and 1% agarose gel electrophoresis. The V3–V4 regions of the 16S rRNA gene were amplified by polymerase chain reaction (PCR). The primers used were 341F: 5′‐CCTACGGGRSGCAGCAG‐3’ and 806R: 5′‐GGACTACVVGGGTATCTAATCAT‐3′. Using the diluted genomic DNA as the template, PCR was performed using the Kapa Hifi Hotstart ReadyMix PCR kit high‐fidelity enzyme. PCR products were detected by 2% agarose gel electrophoresis, and the PCR products were recovered by gel cutting with AxyPrep DNA gel recovery kit (AxyGen Corp.). After recovery, the library was tested by Thermo Nanodrop 2000 UV microspectrophotometer and 2% agarose gel electrophoresis. After the library quality is qualified, Qubit is used for library quantification, and corresponding proportion of mixing is carried out according to the data volume requirements of each sample. Illumina Novaseq PE250 was used for computer sequencing. 16S specific primers were designed to amplify specific regions, and a 425 bp amplified fragment was obtained. In addition, Illumina platform was used to sequence PE250 paired‐end data, and the long sequence was spliced to perform 16S analysis.