Angiotensin I-converting enzyme (ACE) inhibitory activity of razor clam hydrolysates produced using five proteases, namely, pepsin, trypsin, alcalase, flavourzyme and proteases from Actinomucor elegans T3 was investigated. Flavourzyme hydrolysate showed the highest level of degree of hydrolysis (DH) (45.87%) followed by A. elegans T3 proteases hydrolysate (37.84%) and alcalase (30.55%). The A. elegans T3 proteases was observed to be more effective in generating small peptides with ACE-inhibitory activity. The 3 kDa membrane permeate of A. elegans T3 proteases hydrolysate showed the highest ACE-inhibitory activity with an IC₅₀ of 0.79 mg/mL. After chromatographic separation by Sephadex G-15 gel filtration and reverse phase-high performance liquid chromatography, the potent fraction was subjected to MALDI/TOF-TOF MS/MS for identification. A novel ACE-inhibitory peptide (VQY) was identified exhibiting an IC₅₀ of 9.8 μM. The inhibitory kinetics investigation by Lineweaver-Burk plots demonstrated that the peptide acts as a competitive ACE inhibitor. The razor clam hydrolysate obtained by A. elegans T3 proteases could serve as a source of functional peptides with ACE-inhibitory activity for physiological benefits.

Under some conditions, nuclear factor-κB (NF-κB) has a pro-apoptotic role, but the mechanisms underlying this function remain unclear. This study demonstrated that NF-κB directly binds to CASP9 and miR1276 in tumor necrosis factor α (TNFα)-treated HeLa and HepG2 cells. NF-κB upregulated CASP9 expression, whereas downregulated miR1276 expression in the TNFα-treated cells. The miR1276 repressed CASP9 expression in both cells. As a result, a typical NF-κB-mediated coherent feed-forward loop was formed in the TNFα-treated cells. It was proposed that the NF-κB-mediated loop may contribute to cell apoptosis under certain conditions. This opinion was supported by the following evidence: TNFα promoted the apoptosis of HeLa and HepG2 cells induced by doxorubicin (DOX). CASP9 was significantly upregulated and activated by TNFα in the DOX-induced cells. Moreover, a known inhibitor of CASP9 activation significantly repressed the TNFα promotion of apoptosis induced by DOX. These findings indicate that CASP9 is a new mediator of the NF-κB pro-apoptotic pathway, at least in such conditions. This study therefore provides new insights into the pro-apoptotic role of NF-κB. The results also shed new light on the molecular mechanism underlying TNFα-promotion of cancer cells apoptosis induced by some anticancer drugs such as DOX.

Different aromatic components do indeed give different tea flavors. There is still little research on whether there is a certain regularity in the combination and content of aromatic components in different aroma types of Phoenix Dancong (PDC) tea. This potential regularity may be a key factor in unraveling the relationship between reproduction and evolution in PDC tea. Here, the 5 kinds of these 4 aroma types PDC tea (Zhuye, Tuofu, Jianghuaxiang, Juduo, Yashixiang) were used as research materials in this study, the headspace solid-phase microextraction combined with gas chromatography–mass spectrometry was used to analyze the aromatic components of these PDC teas. The results showed a total of 36 aromatic components identified in this study. When conducting cluster analysis, it was found that similarity degree arrangement sequence of 5 PDC teas was Juduo, Tuofu, Yashixiang, Zhuye and Jianghuaxiang. Among these aromatic components, the 7,9-Di-tert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, the 2-Cyclopenten-1-one, 3-methyl-2-(2-pentenyl)-,(Z)-, the 2,4-Di-tert-butylphenol, the 3,7-dimethyl-1,5,7-Octatrien-3-ol, and the 2-Furanmethanol,5-ethenyltetrahydro-.alpha.,.alpha.,5-trimethyl-,cis- are common to 5 PDC teas. This study aims to elucidate the similarities in the aromatic components of 5 PDC teas, revealing the major aroma-endowed substances of various aroma, and providing theoretical reference for further exploring the relationship between aroma type discrimination, variety selection, and evolution of PDC teas.

Bacteria are an integral component of their host. However, information about the microbiota living in and around many aquatic animals is lacking. In this study, multiplex bar-coded pyrosequencing of the 16S ribosomal RNA gene was used to monitor the dynamics of abalone, Haliotis discus hannai, bacterial communities in the intestine, water from cement culture ponds, and surrounding sea areas. Correlations between the bacterial communities and common aquaculture diseases were also evaluated. A total of 329,798 valid sequences and 15,277 operational taxonomic units (OTUs) from 32 samples were obtained by 454 tag amplicon pyrosequencing. The Shannon indices of the seawater samples ranged from 2.84 to 5.6 and the Shannon indices of the abalone intestine samples ranged from 1.2 to 5.12, which were much lower than those of seawater. The dominant phyla in seawater samples were Proteobacteria, Bacteroidetes, Fusobacteria, Cyanobacteria, etc. The dominant phyla in the abalone intestine varied greatly in different months. The dominant genera in the seawater of the cement culture ponds changed in different months, mainly Psychrilyobacter and Pseudoalteromonas. The dominant genera in seawater from the open sea vary considerably between months. The dominant genus of bacteria in the abalone intestine during the months when abalones are susceptible to disease is mainly Mycoplasma spp. Canonical correspondence analysis revealed that bacterial communities in seawater and the intestine responded differently to environmental variables, with similar microbiota in the same area. pH, dissolved oxygen concentration, and temperature were closely related to the samples from the sea area. Oxidation-reduction potential, salinity, phosphate, nitrate, and ammonia nitrogen concentrations were closely related to the water samples from the artificial pools. These findings may add significantly to our understanding of the complex interactions between microbiota and environmental variables in the abalone intestine as well as in the surrounding seawater.

Differences in plant leaf elemental contents due to seasonal climate change reflect potential plant growth strategies. However, the distribution patterns of elements mediated by seasonal climate change remain unclear. This limits assessment of plant growth status and prediction of plant growth dynamics under global climate change. We collected 41 subtropical evergreen broadleaf plant leaves (31 tree species and 10 shrub species) during the wet and dry seasons, and determined foliar contents of macro- and microelements by inductively coupled plasma mass spectrometer. Our results showed that 41 plant leaves had significantly greater macroelement contents and significantly lower microelement contents in wet season than dry season. The highest macroelement content was in tree layer plants in wet season, followed by tree layer plants in dry season and shrub layer plants in wet season, the lowest was in shrub layer plants in dry season. The highest microelement content was in tree and shrub layer plants in dry season, followed by shrub layer plants in wet season, the lowest was in tree layer plants in wet season. Our results show that macro- and microelement contents of plant leaves with different vertical structures are affected by seasonal climate change. The transition from wet to dry season was detrimental to tree layer plants growth, but had less impact on shrub layer plants growth. These findings provide valuable evidence for predicting how different vertically structured subtropical evergreen broadleaf plants can adapt to changes in wet and dry season environments and to future global climate change.

Probiotic treatment is an effective method for enhancing growth performance and improving intestinal flora in aquaculture species. This study examined the effects of three candidate-probiotics (Bacillus, photosynthetic bacteria, and Lactobacillus) on the rate of weight gain and the intestinal flora of abalone juveniles. Haliotis diversicolor was fed a probiotic-supplemented diet for 30 days. The abalones fed with Lactobacillus showed a more significant weight gain rate than those in the Bacillus, photosynthetic bacteria, and control groups. Through 16S rRNA high-throughput sequencing, 12,490 amplicon sequence variants (ASVs) were obtained from the abalone intestinal tract microbiome. After a short feeding period (5 days), the Bacillus and photosynthetic bacteria-treated groups showed an increased abundance of Proteobacteria in the abalone digestive tract. In the Lactobacillus-treated group, the quantity of Proteobacteria decreased, and the abundance of Bacteroidota increased. After 30 days of feeding, the abundance of Proteobacteria and Bacteroidetes at the phylum level was more significant in the Bacillus-treated group and photosynthetic bacteria-treated group than in the controls. The Lactobacillus-treated group showed an increase in the quantity of Proteobacteria and Chloroflexi. The dominant flora of the three probiotic treated groups changed slightly with respect to the control group. After a short period of feeding (5 days), the abundance of Rhodobacteraceae (at the genus level) in the abalone digestive tract increased in the Bacillus- and photosynthetic bacteria-treated groups, whereas in the Lactobacillus-treated group, Rhodobacteraceae decreased, and Maribacter increased in abundance. After 30 days of feeding, Bacteroidetes and Ruegeria were higher in the Bacillus-treated group than in the control group. Marinirhabdus and Bacteroidetes increased in the photosynthetic bacteria-treated group, and Roseivivax and Ruegeria increased in the Lactobacillus-treated group. The three probiotic-treated groups had higher microbial diversity than the control group. Therefore, our findings confirmed that adding Bacillus, photosynthetic bacteria, and Lactobacillus to the abalone diet increased abalones’ weight gain rate and altered their intestinal microbiome composition.