Nondestructive detection of anthocyanin content in fresh leaves of purple maize using hyperspectral data.

Anthocyanins are widely used in the food industry as an additive, improving antioxidant capacity and strengthening the human immune system. However, rapid and nondestructive detection methods are lacking. This study aimed to develop a rapid and nondestructive method to detect anthocyanin content in fresh purple maize leaves using hyperspectral reflectance. Sensitivity bands were screened by analyzing the correlation between the spectrum and anthocyanin, chlorophyll, and moisture content in maize leaves with models constructed. Through a combination of the sensitivity bands of the three components, the interference of chlorophyll and moisture on the spectral detection of anthocyanin in fresh leaves was analyzed. The results showed that the anthocyanin sensitivity band was approximately 550 nm. The determination coefficient and root mean square error of the optimal hyperspectral model were 0.766 and 4.215 mg/g, respectively. After excluding chlorophyll and moisture interference, the anthocyanin content detection accuracy was improved by only 2% compared to that of the original. These results indicate that hyperspectral technology can be used to nondestructively detect anthocyanin content in fresh purple maize leaves with good accuracy. Chlorophyll and moisture in the leaves did not significantly influence anthocyanin content.

Analysis of synonymous codon usage of chloroplast genome in Porphyra umbilicalis.

BACKGROUND: Synonymous codon usage bias is noticed in the genome of every organism, influenced by mutation pressure and natural selection. The analysis of codon usage pattern in Porphyra umbilicalis chloroplast genome are inferred while previous study focused on codon bias in nuclear genome. OBJECTIVE: To develop a better understanding of the factors affecting synonymous codon usage, codon usage patterns and nucleotide composition of 150 genes in P. umbilicalis cp genome, and provide a theoretical basis for genetic modification of chloroplast genome. METHODS: In this study, all codon usage bias parameters and nucleotide compositions were calculated by Python script, Codon W, DNA Star, CUSP of EMBOSS and Microsoft Excel. RESULTS: It shows that codon usage models are mainly influenced by compositional constraints under mutational pressure and synonymous codon prefers to use codons ending with A/T, comparing to C/G. The ENC value is slight low which shows the weak codon bias. For all coding genes of P. umbilicalis chloroplast genome except Photosystem I genes, a weak correlation between GC3 and GC12 suggests natural selection might play a significant role in synonymous codon usage bias. CONCLUSION: The codon usage bias in P. umbilicalis cp genome is low and in some way or other, influenced by natural selection, mutation pressure, nucleotide composition. Our results can provide a theoretical basis for codon modification of exogenous genes, accuracy of prediction about new members of chloroplast gene family and identification of unknown genome.