Small-leaved Kuding tea (SLKDT) obtained from Ligustrum robustum is a traditional tea substitute in southern China and has a range of physiological effects. However, the changes in its phytochemical composition after various heat treatments are not reported yet. Thus, the phytochemical composition and antioxidant activities of fresh leaves of SLKDT (LrF1) and SLKDT after high-temperature wet-heat treatment (LrF2) and wet-and dry-heat treatments (LrF3) were assessed using liquid chromatography-mass spectrometry, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities and lipid peroxidation inhibition activity of LrF1 and LrF3 were investigated. The results indicated that the phytochemical composition of LrF1, LrF2, and LrF3 was significantly different. Overall, 258 and 83 differential constituents, respectively, were obtained in LrF1 versus LrF2 and LrF2 versus LrF3. The differential constituents mainly included amino acids and their derivatives, nucleosides, flavonoids, terpenoids, simple phenylpropanoids, and coumarins. After heat treatment, SLKDT exhibited obvious changes in sensory characteristics and physiological properties, which may be related to the changes in the levels of amino acids, linalool, beta-geraniol, myricetin, naringin, fraxetin, and isoacteoside. Moreover, the antioxidant activities significantly changed after heat treatment of SLKDT. Overall, our study demonstrated that heat treatment can alter the phytochemical composition of SLKDT, thus affecting its sensory properties and physiological properties.

Wetlands are the most biologically diverse ecosystems on Earth. The isolation of Streptomyces strains from wetlands is helpful to study their diversity and functions in such habitats. In this study, six strains of Streptomyces were isolated from the rhizosphere soil of three plant species in Huaxi Wetland of Guiyang and were identified as Streptomyces galilaeus, S. avidinii, S. albogriseolus, S. hydrogenans, S. spororaveus, and S. cellulosae, respectively. The six strains all solubilized phosphate, fixed nitrogen, and produced ACC deaminase and siderophores, and four strains also secreted indole-3-acetic acid. The six strains grew well in the ranges of 0%–3% NaCl, 0%–25% PEG, and pH 5.0–10.0, which showed that the screened strains were tolerant to certain degrees of salinity, drought, and acidic/alkaline pH stress. In addition, the S. avidinii WL3 and S. cellulosae WL9 strains (especially the former) significantly promoted seed germination of mung bean, pepper, and cucumber. A pot experiment further showed that WL3 significantly promoted the growth of cucumber seedlings compared with that of the control, with plant height, root length, lateral root number, and fresh weight increased by 104.99%, 49.99%, 94.12%, and 82.86%, respectively. Thus, strains of six species of Streptomyces with multiple plant growth-promoting characteristics were isolated from the wetland. These results lay a foundation for their potential use as microbial agents and seed-coating treatments.

Machilus chuanchienensis is an ecological tree distributed in southwestern China. It has a significant valuation with making Hawk tea using its leaves, an ethnic traditional tea-like beverage with a long history in Chinese tea culture. The whole chloroplast (cp) genome is an ideal model for the phylogenetic study of Lauraceae because of its simple structure and highly conserved features. There have been numerous reports of complete cp genome sequences in Lauraceae, but little is known about M. chuanchienensis. Here, the next-generation sequencing (NGS) was used to sequence the M. chuanchienensis cp genome. Then, a comprehensive comparative genome analysis was performed. The results revealed that the M. chuanchienensis’s cp genome measured 152,748 base pairs (bp) with a GC content of 39.15% and coded 126 genes annotated, including comprising eight ribosomal RNA (rRNA), 36 transporter RNA (tRNA), and 82 protein-coding genes. In addition, the cp genome presented a typical quadripartite structure comprising a large single-copy (LSC; 93,811) region, a small single-copy (SSC; 18,803) region, and the inverted repeats (IRs; 20,067) region and contained 92 simple sequence repeat (SSR) locus in total. Phylogenetic relationships of 37 species indicated that M. chuanchienensis was a sister to M. balansae, M. melanophylla, and M. minutiflora. Further research on this crucial species may benefit significantly from these findings.

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Actinodaphne cupularis is a multi-purpose tree that grows in central or southwest China and is one of the primary source plants for making Hawk tea . In this study, we firstly assembled and characterized the complete chloroplast (cp) genome of A. cupularis using Illumina pair-end sequencing. The results revealed that the total length of the cp genome was 152,748 bp with 39% of the guanine-cytosine content, including a pair of 20,066 bp reverse repeat regions, a large single-copy region with 93,788 bp, and a small single-copy region with 18,828 bp. One hundred twenty-four genes were identified, including eight rRNA genes, 36 tRNA genes, and 80 protein-coding genes. In addition, the maximum likelihood phylogenetic tree was constructed between the cp genome of A. cupularis and its related species. The results suggested that A. cupularis was more closely related to Actinodaphne obovate and then formed a sister clade with the Machilus genus. This study not only analyzed the cp genome characteristic information of A. cupularis but also provided a specific basis and foundation for future research.