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Background Camellia sinensis ‘Huangjinju’ is an albino tea variety developed recently in China. Young leaves of ‘Huangjinju’ demonstrate bright yellow when cultivated under natural sunlight, but regreens under reduced light intensity. To elucidate the physiological and molecular mechanisms of this light-sensitive albinism, we compared leaf pigmentation, metabolites, cellular ultrastructure and transcriptome between plants cultured under natural sunlight and shade. Results Shading treatment doubled the chlorophyll concentration and regreened albino leaves; carotenoid also increased by 30%. Electron microscopy analyses showed that chloroplast not only increased in number but also in size with a complete set of components. In addition, regreened leaves also had a significantly higher concentration of polyphenols and catechins than albino leaves. At transcriptomic level, a total of 507 genes were differentially expressed in response to light condition changes. The most enriched pathways include light harvest protein complex, response to stimuli, oxidation-reduction process, generation of precursor metabolites and energy response. Conclusion The integrated strategy in this study allows a mechanistic understanding of leaf albinism in light-sensitive tea plants and suggested the regulation of gene networks involved in pigmentation and protein processing. Results from this study provide valuable information to this area and can benefit the domestication and artificial breeding to develop new albino tea varieties.

Pu-erh tea, a traditional Chinese beverage, has been believed to have many benefits to human health and without side effects. In this study, we systematically analyzed the main active components of Pu-erh tea and investigated its anti-obesity, anti-atherosclerotic and anti-oxidant effects using an obese rat model. Obesity was induced by feeding a high-fat diet and subsequently the experimental obese mice were fed with high-fat diet supplemented with low (2.5%), medium (5%) or high (7.5%) doses of Pu-erh tea powder for 6 weeks respectively. As result, the body weight gain of the rats was decreased by medium and high doses of Pu-erh tea treatments. Furthermore, the levels of serum total cholesterol (TC), triglyceride (TG) and atherosclerosis index (AI) were significantly lowered by Pu-erh tea compared to the control group. Conversely, high density lipoproteincholesterol (HDL-C) level of the rats was significantly elevated by Pu-erh tea treatments. In addition, Pu-erh tea treatments increased the activities of anti-oxidative enzymes such as superoxide dismutase (SOD) and glutathione peroxides (GSH-Px), whereas reduced the level of lipid peroxidation product malondialdehyde (MDA) in obese rats. Collectively, our find-ings revealed that Pu-erh tea exerts comprehensive benefits in anti-obesity, anti-atherosclerotic and anti-oxidant effects, therefore can be used as a promising functional food in obesity management.

Fixing, shaping, and drying are three major processing procedures after green tea's harvest. Among them, fixing is the first and key step for the formation of green tea's specific appearance and fragrance. With traditional methods, only trained experts with years' experience can produce good green tea products, which is backward in the industrial age. In this study, intelligent green tea fixation is designed to automatically and continuously adjust the processing parameters. Aroma is online measured with an electronic nose and a few sensors' signals are selected to represent the fresh fragrance, enzymatic reaction, charring occurrence, respectively. Image information is captured with machine vision and G, R, B values are carefully processed to reflect the color changes. The original aroma signals and processed image information were fed into an adaptive fuzzy logic controller to automatically control the pot temperature continuously. With a controlled high temperature at the beginning, the enzymatic reaction could be suppressed and more polyphenols and chlorophyll were retained. In the later phase the temperature was decreased to minimize charring, and more aroma and contents were retained. The final product quality was hence greatly improved in terms of appearance, liquor color, fragrance, taste, and residue color.

Additional file 4: Fig. S1. Gene ontology enrichment of differentially expressed genes identified in leaves under direct sunlight versus under shade. Only up to 10 terms are selected to present. Horizontal redline represents the threshold of significance after false discovery rate correction.

In the past in the higher vocational education the entity class teaching mode is generally adopted in the process of public English teaching, in recent years due to the rapid development of Internet information technology and the emergence of multimedia teaching methods, to gradually change the traditional English teaching mode to entity class teaching and online mutual combination of Internet teaching. This new hybrid English teaching method has both the advantages of physical classroom teaching and the new advantages of online learning. It is a brand-new way of learning English. Interactive English platform is a new model of this new way of learning English. This paper will take this platform as an example and focus on the methods of learning public English in colleges and universities.