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The chemical composition, quality characteristics, antioxidant activity, and "golden flower" fungi morphology of Fu brick tea from Hunan, Hubei, Shaanxi, Guizhou, and Zhejiang provinces of China had been researched in this study. The results revealed significant differences in the contents of chemical components in different Fu brick tea (P

Purple tea, renowned for its anthocyanin content and distinctive purple hue, has gained prominence. The anthocyanin content in purple tea can exceed three times that of traditional green-leaf tea. Purple tea harbors various anthocyanins, implicating intricate pathways of biosynthesis and transcriptional regulation. Concurrently, owing to its distinctive chemical composition, the processing of purple tea may be constrained, potentially influencing the sensory attributes and flavor profile of the tea. The richness of anthocyanins in purple tea has yielded potential health benefits, including antioxidative and anti-cancer properties, rendering purple tea a sought-after commodity in the tea market. However, current research on purple tea remains incomplete, including indistinct networks of anthocyanin biosynthesis and regulatory mechanisms, incomplete chemical characterization, and a need for comprehensive investigations into its biological activities. The limited research foundation has greatly reduced the popularity and consumption of purple tea. This paper aims to provide an overview of recent advancements in the biosynthesis and regulation of anthocyanins, as well as the chemical compositions, processing, and health benefits of purple tea. This review will provide the groundwork for future efforts in the selection and innovation of purple tea germplasm, purple tea processing, and the expansion of the market for purple tea consumption.

Shaken Hunan black tea is an innovative Hunan black tea processed by adding shaking to the traditional Hunan black tea. The quality of shaken black tea is influenced by leaf grades of different maturity. In this study, the taste and aroma quality of shaken Hunan black tea processed with different grades were analyzed by sensory evaluation (SP, HPLC, and HS-SPME/GC-MS). The results showed that shaken Hunan black tea processed with one bud and two leaves has the best quality, which has a sweet, mellow, and slightly floral taste, as well as a floral, honey, and sweet aroma. Moreover, caffeine and EGCG were identified as the most important bitter and astringent substances in shaken Hunan black. Combined with the analysis of GC-MS and OAV analysis, geraniol, jasmone, β-myrcene, citral, and trans-β-ocimene might be the most important components that affect the sweet aroma, while methyl jasmonate, indole, and nerolidol were the key components that affect the floral aroma of shaken Hunan black tea. This study lays a foundation for this study of the taste and aroma characteristics of shaken Hunan black tea and guides enterprises to improve shaken black tea processing technology.

Automatic road extraction from remote sensing images plays an important role for navigation, intelligent transportation, and road network update, etc. Convolutional neural network (CNN)-based methods have presented many achievements for road extraction from remote sensing images. CNN-based methods require a large dataset with high quality labels for model training. However, there is still few standard and large dataset, which is specially designed for road extraction from optical remote sensing images. Besides, the existing end-to-end CNN models for road extraction from remote sensing images are usually with symmetric structure, studying on asymmetric structure between encoding and decoding is rare. To address the above problems, this article first provides a publicly available dataset LRSNY for road extraction from optical remote sensing images with manually labelled labels. Second, we propose a reconstruction bias U-Net for road extraction from remote sensing images. In our model, we increase the decoding branches to obtain multiple semantic information from different upsamplings. Experimental results show that our method achieves better performance compared with other six state-of-the-art segmentation models when testing on our LRSNY dataset. We also test on Massachusetts and Shaoshan datasets. The good performances on the two datasets further prove the effectiveness of our method.

Camellia sinensis cv. ‘Yanlingyinbiancha’ is a leaf-variegated mutant with stable genetic traits. The current study aimed to reveal the differences between its albino and green tissues, and the molecular mechanism underlying the variegation. Anatomic analysis showed the chloroplasts of albino tissues to have no intact lamellar structure. Photosynthetic pigment in albino tissues was significantly lower than that in green tissues, whereas all catechin components were more abundant in the former. Transcriptome analysis revealed most differentially expressed genes involved in the biosynthesis of photosynthetic pigment, photosynthesis, and energy metabolism to be downregulated in albino tissues while most of those participating in flavonoid metabolism were upregulated. In addition, it was found cryptochrome 1 (CRY1) and phytochrome B (PHYB) genes that encode blue and red light photoreceptors to be downregulated. These photoreceptors mediate chloroplast protein gene expression, chloroplast protein import and photosynthetic pigment biosynthesis. Simultaneously, SUS gene, which was upregulated in albino tissues, encodes sucrose synthase considered a biochemical marker for sink strength. Collectively, we arrived to the following conclusions: (1) repression of the biosynthesis of photosynthetic pigment causes albinism; (2) destruction of photoreceptors in albino tissues suppresses photomorphogenesis, leading to abnormal chloroplast development; (3) albino tissues receive sucrose from the green tissues and decompose their own storage substances to obtain the energy needed for survival; and (4) UV-B signal and brassinosteroids promote flavonoid biosynthesis.