Revealing Hidden Vibration Polariton Interactions by 2D IR Spectroscopy

We report the first experimental two-dimensional infrared (2D IR) spectra of novel molecular photonic excitations - vibrational-polaritons. The application of advanced 2D IR spectroscopy onto novel vibrational-polariton challenges and advances our understanding in both fields. From spectroscopy aspect, 2D IR spectra of polaritons differ drastically from free uncoupled molecules; from vibrational-polariton aspects, 2D IR uniquely resolves hybrid light-matter polariton excitations and unexpected dark states in a state-selective manner and revealed hidden interactions between them. Moreover, 2D IR signals highlight the role of vibrational anharmonicities in generating non-linear signals. To further advance our knowledge on 2D IR of vibrational polaritons, we develop a new quantum-mechanical model incorporating the effects of both nuclear and electrical anharmonicities on vibrational-polaritons and their 2D IR signals. This work reveals polariton physics that is difficult or impossible to probe with traditional linear spectroscopy and lays the foundation for investigating new non-linear optics and chemistry of molecular vibrational-polaritons

An amateur gut microbial configuration formed in giant panda for striving to digest cellulose in bamboo: Systematic evidence from intestinal digestive enzymes, functional genes and microbial structures

The giant panda has been considered to maximize nutritional intake including protein and soluble carbohydrates in bamboo, but it has spent almost entire life with the high-cellulose diet. Whether giant panda is still helpless about digesting bamboo cellulose or not is always contentious among many researchers around the world. The work has systematically clarified this issue from the perspectives of digestive enzymes, functional genes, and microbial structures in giant panda gut. The intestinal cellulase activities of panda increase with bamboo consumption, performing that the endoglucanase activity of adults reaches 10-fold that of pandas first consuming bamboo. More abundance and types of microbial endoglucanase genes occur in bamboo-diet giant panda gut, and the corresponding GH5 gene cluster is still efficiently transcribed. Gut microbes possessing cellulose-degrading genes, belong to the phylum Firmicutes and some Bacteroidetes, but their structural and functional configurations are insufficient to completely degrade cellulose. Therefore, giant panda is striving to digest cellulose in bamboo, but this adaptation is incomplete. This is probably related to the short straight carnivore-like gut structure of the giant panda, preventing the colonization of some efficient functional but anaerobic-preferred flora

Isolation and extraction of glansreginin A from walnut meal and its effect on the proliferation of 3T3-L1 cells

Abstract Glansreginin A is an indicative component in walnut and is abundant in walnut meal. The aim of this study was to isolate and purify glansreginin A from the walnut meal, and to investigate the weight loss and lipid-lowering potential of glansreginin A by studying the effect of glansregin A on the proliferation of 3T3-L1 preadipocytes. Firstly, the response surface methodology was used to effectively improve the extraction yield of glansreginin A. The maximum extraction rate of glansreginin A was 0.363%, and the optimal extraction process conditions were determined. In addition, the lipid-lowering activity of glansreginin A was investigated by cell experiments. The results showed that glansreginin A could inhibit the proliferation of 3T3-L1 preadipocytes in a dose-dependent manner. And cell cycle of different groups of cells treated with glansreginin A was also measured using flow cytometry. The results showed most of the cells were blocked in G0/G1 phase and significantly decreased in S phase. These results suggest that glansreginin A could inhibit the proliferation of 3T3-L1 preadipocytes by causing cell cycle arrest. These findings provided a theoretical basis for the future research of glansreginin A and the development of slimming and fat-reducing foods

Metagenomic Analysis of Bacteria, Fungi, Bacteriophages, and Helminths in the Gut of Giant Pandas

To obtain full details of gut microbiota, including bacteria, fungi, bacteriophages, and helminths, in giant pandas (GPs), we created a comprehensive microbial genome database and used metagenomic sequences to align against the database. We delineated a detailed and different gut microbiota structures of GPs. A total of 680 species of bacteria, 198 fungi, 185 bacteriophages, and 45 helminths were found. Compared with 16S rRNA sequencing, the dominant bacterium phyla not only included Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria but also Cyanobacteria and other eight phyla. Aside from Ascomycota, Basidiomycota, and Glomeromycota, Mucoromycota, and Microsporidia were the dominant fungi phyla. The bacteriophages were predominantly dsDNA Myoviridae, Siphoviridae, Podoviridae, ssDNA Inoviridae, and Microviridae. For helminths, phylum Nematoda was the dominant. In addition to previously described parasites, another 44 species of helminths were found in GPs. Also, differences in abundance of microbiota were found between the captive, semiwild, and wild GPs. A total of 1,739 genes encoding cellulase, β-glucosidase, and cellulose β-1,4-cellobiosidase were responsible for the metabolism of cellulose, and 128,707 putative glycoside hydrolase genes were found in bacteria/fungi. Taken together, the results indicated not only bacteria but also fungi, bacteriophages, and helminths were diverse in gut of giant pandas, which provided basis for the further identification of role of gut microbiota. Besides, metagenomics revealed that the bacteria/fungi in gut of GPs harbor the ability of cellulose and hemicellulose degradation

Pregnancy length and health in giant pandas: what can metabolic and urinary endocrine markers unveil?

Mature female giant pandas usually ovulate once a year. This is followed by an obligatory luteal phase, consisting of a long-lasting corpus luteum dormancy phase (CLD; primary increase in progestogens) and a much shorter active luteal phase (AL; secondary increase in progestogens). Varying duration of both the dormant (embryonic diapause) and AL (post-embryo reactivation) phases has hampered unambiguous pregnancy length determination in giant pandas until today. Additionally, progestogen profiles have been considered not to differ between pregnant and pseudopregnant cycles. Only ceruloplasmin, 13,14-dihydro-15-keto-PGF2α (PGFM) and – more recently – estrogens have been assigned diagnostic power so far. Our study investigated the competence of metabolic (fecal output) and Urinary Specific Gravity (USpG)-normalized urinary endocrine (progestogens, PGFM, glucocorticoids (GCM) and ceruloplasmin) markers for pregnancy monitoring including defining the duration of the AL phase length. Research on 24 (6 pregnant, 8 pseudopregnant and 10 non-birth) cycles of 6 giant pandas revealed a fixed AL phase length of 42 days in giant pandas, e.g. representing 6 weeks of post- diapause development in case of pregnancy. Progestogen concentrations were significantly higher in pregnant cycles throughout the majority of the AL phase, with significant higher values during the AL phase in healthy twin compared to singleton pregnancies. GCM concentrations were also markedly higher in giant pandas expecting offspring, with a clear increase towards birth in the final 2 weeks of pregnancy. This increase in GCM was running in parallel with elevating estrogen and PGFM concentrations, and decreasing progestogens. In addition, during the AL phase, a more pronounced decrease in fecal output was obvious for pregnant females. The combined profiles of non-invasive metabolic and endocrine markers, the latter normalized based on USpG, showed a true pregnancy signature during the AL phase. The findings of this study are applicable to retrospective evaluations of non-birth cycles facilitating categorizing those into pseudopregnant or lost pregnancies, with USpG-normalization of the urinary endocrine markers as a prerequisite