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The free and bound phenolic profiles and their bioactivities of radix puerariae thomsonii (RPT) cultivars from 7 growing regions in China were investigated. Total phenolic and flavonoid contents were from 148.71 to 435.32 mg gallic acid equivalents /100 g dry weight and 561.93 to 826.11 mg catechin equivalents /100 g dry weight, respectively, with 20.64–38.28% and 32.77–47.29% contribution from bound fractions. Sixteen phenolic compounds were detected in RPTs. Bound fractions contributed 28.15–70.84% to the total antioxidant activities. The cultivars from Qiannan and Guangzhou showed much higher regulatory effects on carbohydrate hydrolyzing enzymes and alcohol metabolizing enzymes than the other cultivars. The bound fractions exhibited equivalent EC50 values for alcohol metabolizing enzymes and IC50 values for carbohydrate hydrolyzing enzymes to the free fractions in RPT cultivars. Therefore, bound phenolics significantly contributed to the potential health benefits of RPT. The results provided information for the utilization of RPT for health promoting purpose.

In recent years, more and more metal oxides have been finding critical tribo-catalytic applications. Presently, we have explored the tribo-catalytic conversion of H2O and CO2 using Co3O4 nanoparticles and obtained some surprising results. In an as-received 150 mL glass reactor enclosed with 10 mL of H2O, 0.10 g of Co3O4 nanoparticles, 1 atm of CO2, and a Teflon magnetic rotary disk, we observed the production of as much as 57.41 µmol/L of H2, 0.15 µmol/L of CH4, and 0.21 µmol/L of CO after 5 h of magnetic stirring. Metallic coatings of Cu, Ni, SUS316, Ti, Nb, Mo, and W were further introduced on reactor bottoms separately. For those coatings of Ni, SUS316, Ti, and Nb, the reduction of CO2 was dramatically enhanced, and C2+ products of C2H6 and C2H4 were observed. Especially for the Ti coating, the amounts of H2 and CH4 were increased by 2 and 26 times from those for the glass bottom, respectively, and the amounts of C2H6 and C2H4 were very impressive. The Co3O4 nanoparticles were proven chemically stable under magnetic stirring in water, and hydroxyl radicals and superoxide radicals have been detected for the Co3O4 nanoparticles under magnetic stirring through fluorescence spectroscopy and electron paramagnetic resonance spectroscopy analyses. These findings not only reveal outstanding capability of Co3O4 to generate multicarbon products from H2O and CO2 through tribo-catalysis but also highlight a promising potential of tribo-catalysis as a whole to harness mechanical energy for addressing energy shortages and environmental pollution.

Previous results indicated that the flavonoid profiles might have varietal differences in pomelo, but detailed information is unknown. We previously isolated 4 new flavonoids, cigranoside C, D, E, F, in Citrus grandis Shatianyu pulp. However, their distribution in different pomelo cultivars remains to be explored. Therefore, the flavonoid profiles and in vitro bioactivity of the pulp from 5 pomelo and 1 grapefruit cultivars commonly consumed in China were investigated. Fourteen flavonoids were identified, cigranoside C, D, E were detected in these pomelo and grapefruit. Naringin and cigranoside C were the major flavonoids in grapefruit, Guanximiyu-W, Guanximiyu-R and Liangpingyu, while melitidin and rhoifolin was the predominant flavonoid in Shatianyu and Yuhuanyu, respectively. Pomelo and grapefruit showed strong antioxidant activity, and were potent inhibitors of pancreatic lipase with IC50 values of 11.4–72.6 mg fruit/mL except Shatianyu. Thus, pomelo and grapefruit are natural antioxidants and possess anti-obesity potential.

The H1N1 influenza virus is highly infectious and pathogenic, and in recent years, it has often presented seasonal mass outbreaks of infection. People infected with H1N1 will develop a high fever and other respiratory infection symptoms. If not treated in time, complications such as pneumonia may occur. In this study, we focused on developing drugs that can effectively fight against with H1N1 virus. A flavonoid glycoside was extracted from the carambola, then characterized by HR-ESI-MS with the molecular formula C47H58O2, and named carambolaside W. The flavonoid glycosides were found to have good anti-H1N1 influenza virus effects. In this study, we verified that carambolaside W has low toxicity and can effectively inhibit influenza virus replication in vitro. H1N1 virus infection induces intracellular oxidative stress damage to accelerate disease progression. The results showed that carambolaside W effectively inhibited the oxidative stress caused by H1N1 infection. The Western blot assay also revealed that carambolaside W alters the expression of apoptosis-related proteins in vitro and exerts a good anti-H1N1 influenza virus effect. In summary, carambolaside W is a low-toxicity natural flavonoid that can effectively treat the H1N1 influenza virus as a potential anti-H1N1 virus agent.

This study investigated the chemical structures and probiotic potential of different polysaccharides (LPs) extracted from the litchi pulp that fermented with Lactobacillus fermentum for different times (i.e., 0–72 h corresponding to LP-0 through LP-72, respectively). Fermentation times affected the yields, total sugar contents, uronic acid contents, molecular weights, and monosaccharide compositions of LPs. The LPs yields and uronic acid contents exhibited irregular trends in association with fermentation time, while total sugar contents decreased, and the molecular weights increased. Particularly, LP-6 contained the highest extraction yields (2.67%), lowest uronic acid contents, and smallest average Mw (104 kDa) (p < 0.05). Moreover, analysis of the monosaccharide composition in the fermented LPs indicated that the proportions of glucose decreased, while arabinose and galacturonic acid proportions increased relative to unfermented LP-0. Further, LP-6 demonstrated the highest growth for Bifidobacterium compared to LP-0, while the other fermentation time led to comparable or worse probiotic promoting activities. These results suggest that lactic acid bacteria fermentation alters the physicochemical properties of litchi polysaccharides, such that suitable fermentation time can enhance their probiotic activities.

Litchi polysaccharides are a kind of macromolecular polymers with various biological activities and a wide range of molecular weights. In this study, two separate fractions, with average molecular weights of 378.67 kDa (67.33%) and 16.96 kDa (6.95%), which were referred to as LP1 and LP2, respectively, were separated using an ultrafiltration membrane. Their physicochemical properties, and immunomodulatory and prebiotic activity were compared. The results revealed that LP2 contained more neutral sugar, arabinose, galactose and rhamnose, but less uronic acid, protein, mannose and glucose than LP1. Compared with LP1, LP2 possessed higher solubility and lower apparent viscosity. LP2 exhibited stronger stimulation on macrophage secretion of NO, TNF-α and IL-6, as well as better proliferation of Lactobacillus plantarum, Leuconostoc mesenteroides, Lactobacillus casei and Bifidobacterium adolescentis. These results suggest that an ultrafiltration membrane might be used to prepare a highly-active polysaccharide fraction from litchi pulp that may be used for food or drug development.

More and more metal oxide nanomaterials are being synthesized and investigated for degradation of organic pollutants through harvesting friction energy, yet the strategy to optimize their performance for this application has not been carefully explored up to date. In this work, three commercially available ZnO powders are selected and compared for tribocatalytic degradation of organic dyes, among which ZnO-1 and ZnO-2 are agglomerates of spherical nanoparticles around 20 nm, and ZnO-3 are particles of high crystallinity with a regular prismatic shape and smooth surfaces, ranging from 50 to 150 nm. Compared with ZnO-1 and ZnO-2, ZnO-3 exhibits a much higher tribocatalytic degradation performance, and a high degradation rate constant of 6.566 × 10−2 min−1 is achieved for RhB, which is superior compared with previous tribocatalytic reports. The stability and universality of ZnO-3 were demonstrated through cycling tests and degradation of different types of dyes. Furthermore, the mechanism of tribocatalysis revealed that h+ was the main active species in the degradation process by ZnO. This work highlights the great significance of high crystallinity rather than a large specific surface area for the development of high-performance tribocatalysts and demonstrates the great potential of tribocatalysis for water remediation.

Rice bran is a by-product of rice milling, which contains variety of nutrients, and has been reported to possess various activities. Here, we used high fat (HF) diet induced mice to investigate the effects of rice bran phenolic extracts (RBPE) on lipid metabolism. Sixteen-week intake of RBPE (200 mg/kg/d and 400 mg/kg/d) significantly improved the serum lipid profiles of HF diet-fed mice and ameliorated HF diet-induced liver steatosis. Further study showed that RBPE might regulate lipid metabolism through increasing the levels of serum adiponectin, and thereby promoting the activation of 5′ adenosine monophosphate-activated protein kinase α (AMPKα) in liver. Taken together, RBPE might regulate lipid metabolism through adiponectin-mediated AMPK activation and the subsequent reduction of lipid biosynthesis together with the increase of fatty acid oxidation in liver. These results provide us new evidence of the health benefits of rice bran.

The fruit of Averrhoa carambola L. (Oxalidaceae) is a commercially important fruit. Our study on the chemical constituents present in the fresh sweet fruit led to the isolation of eleven non-flavonoid phenolic compounds. Their structures were identified by analyses of spectroscopic data. They were two new alkyl phenol diglucosides, carambolasides K (1) and L (2), four phenylpropanoids, (+)-isolariciresinol 9-O-β-d-glucoside (3), (+)-lyoniresinol 9-O-β-d-glucoside (4), (−)-lyoniresinol 9-O-β-d-glucoside (5), and 1-O-feruloyl-β-d-glucose (6), three benzoic acids, protocatechuic acid (7), 1-O-vanilloyl-β-d-glucose (8), and tecomin (9), a simple phenol, koaburaside (10), and a naphthoquinone, (+)-cryptosporin (11). All of them were reported from A. carambola fruit for the first time. Compounds 1–8 and 10 showed 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activity comparable to l-ascorbic acid, while compounds 3, 5, and 7 exhibited potent ferric reducing antioxidant power (FRAP). In addition, compounds 6 and 11 demonstrated weak porcine pancreatic lipase inhibitory activity.

Star fruit (the fruit of Averrhoa carambola L., Oxalidaceae) is popular in tropical regions. Chemical study of the fruit yielded four new dihydrochalcone C-glycosides, carambolasides A (1), B (2), C (3), and D (4), in addition to hovertichoside C (5), isovitexin 2″-O-α-l-rhamnopyranoside (6), and carambolaflavone (7). Their structures were identified by spectroscopic and chemical methods, including electronic circular dichroism (ECD) calculation. Compounds 5–7 were reported from the fruit for the first time. Compounds 1–7 were evaluated for antioxidant activity using three assays. All of them exhibited 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activity with IC50 values ranging from 7.6 to 3.9 µM, which were more potent than l-ascorbic acid (IC50 = 11.6 µM). However, they were inactive in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and in ferric reducing antioxidant power (FRAP).

The fruit of Averrhoa carambola L. (Oxalidaceae), commonly known as star fruit or carambola, is popular in tropical and subtropical regions. Carotenoid-derived components, mainly C13- and C15-norisoprenoids, contribute greatly to the flavor of star fruit. Previously reported norisoprenoids were tentatively identified by GC-MS analysis after enzymatic hydrolysis. To gain accurate information about glycosidically bound flavor precursors in star fruit, a phytochemical study was conducted, which led to the isolation of 16 carotenoid derivatives—One new C13-norisoprenoid glucoside, (5R,6S,7E,9R)-5,6,9-trihydroxy-7-megastigmene 9-O-β-d-glucoside (1); one new C15-norisoprenoid, (6S,7E,10S)-Δ9,15-10-hydroxyabscisic alcohol (11); and 14 known ones, of which 12 were in glucoside form. The structures of the two new compounds were elucidated on the basis of extensive spectroscopic data analysis and chemical reaction. Compound 11 was a rare C15-norisoprenoid with a double bond between C-9 and C-15, and its possible biogenetic pathway was proposed. The known compounds were identified by comparison of their mass and nuclear magnetic resonance (NMR) data with those reported in the literature. The structure identification of one new (1) and seven known (3–7, 9, and 10) C13-norisoprenoid glucosides from the genus Averrhoa for the first time enriches the knowledge of carotenoid-derived flavor precursors in star fruit.

BACKGROUND: Recent studies reveal that dietary fiber (DF) might play a critical role in the metabolism and bioactivity of flavonoids by regulating gut microbiota. We previously found that Shatianyu (Citrus grandis L. Osbeck) pulp was rich in flavonoids and DF, and Shatianyu pulp flavonoid extracts (SPFEs) were dominated by melitidin, obviously different from other citrus flavonoids dominated by naringin. The effects of Shatianyu pulp DF (SPDF) on the microbial metabolism and bioactivity of SPFEs is unknown. RESULTS: An in vitro colonic fermentation model was used to explore the effects of SPDF on the microbial metabolism and antioxidant activity of SPFEs in the present study. At the beginning of fermentation, SPDF promoted the microbial degradation of SPFEs. After 24 h-fermentation, the supplemented SPFEs were almost all degraded in SPFEs group, and the main metabolites detected were the dehydrogenation, hydroxylation and acetylation products of naringenin, the aglycone of the major SPFEs components. However, when SPFEs fermented with SPDF for 24 h, 60.7% of flavonoid compounds were retained, and SPFEs were mainly transformed to the ring fission metabolites, such as 3-(4-hydroxyphenyl) propionic acid, 3-phenylpropionic acid and 3-(3-hydroxy-phenyl) propionic acid. The fermentation metabolites of SPFEs showed stronger antioxidant activity than the original ones, with a further increase in SPDF supplemented group. Furthermore, SPFEs enriched microbiota participating in the deglycosylation and dehydrogenation of flavonoids, while co-supplementation of SPDF and SPFEs witnessed the bloom of Lactobacillaceae and Lactobacillus, contributing to the deglycosylation and ring fission of flavonoids. [ABSTRACT FROM AUTHOR]

Monitoring soil conditions is of great significance for guiding fruit tree production and increasing yields. Achieving a rapid determination of soil physicochemical properties can more efficiently monitor soil conditions. Traditional sampling and survey methods suffer from slow detection speeds, low accuracy, limited coverage, and require a large amount of manpower and resources. In contrast, the use of hyperspectral technology enables the precise and rapid monitoring of soil physicochemical properties, playing an important role in advancing precision agriculture. Yuxi City, Yunnan Province, was selected as the study area; soil samples were collected and analyzed for soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), and available nitrogen (AN) contents. Additionally, soil spectral reflectance was obtained using a portable spectroradiometer. Hyperspectral characteristic bands for soil nutrients were selected from different spectral preprocessing methods, and different models were used to predict soil nutrient content, identifying the optimal modeling approach. For SOM prediction, the second-order differentiation-multiple stepwise regression (SD-MLSR) model performed exceptionally well, with an R2 value of 0.87 and RMSE of 6.61 g·kg−1. For TN prediction, the logarithm of the reciprocal first derivative-partial least squares regression (LRD-PLSR) model had an R2 of 0.77 and RMSE of 0.37 g·kg−1. For TP prediction, the logarithmic second-order differentiation-multiple stepwise regression (LTSD-MLSR) model had an R2 of 0.69 and RMSE of 0.04 g·kg−1. For AN prediction, the logarithm of the reciprocal second derivative-partial least squares regression (LRSD-PLSR) model had an R2 of 0.83 and RMSE of 24.12 mg·kg−1. The results demonstrate the high accuracy of these models in predicting soil nutrient content.