Sea buckthorn (Hippophae rhamnoides L.) fermentation liquid protects against alcoholic liver disease linked to regulation of liver metabolome and the abundance of gut microbiota.

BACKGROUND: Alcoholic liver disease (ALD) refers to liver damage caused by long-term heavy drinking, which causes oxidative stress and changes in gut microbiota. In this paper, we investigated the hepatoprotective effect of sea buckthorn fermentation liquid on ALD in mice and the interaction between ALD and gut microbiota using animal experiments and gut microbiota measurements. RESULTS: We found that the contents of total flavonoids, total triterpenes and related short-chain fatty acids (SCFAs) in sea buckthorn fermentation liquid (SFL) were significantly greater. Liver index, kidney index, spleen index, serum indexes of liver injury - alanine aminotransferase (ALT) and spartate aminotransferase (AST), inflammatory factors in liver tissues - tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), oxidation indexes - malondialdehyde (MDA) and superoxide dismutase (SOD), and lipid metabolism indexes - high-density liptein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and triglyceride (TG), suggested that SFL significantly ameliorates liver injury caused by alcohol. By measuring gut microbiota in mice feces samples, we found that the high-dose group of SFL reversed the declining trend of the gut microbiota Firmicutes/Bacteroidetes (F/B) ratio caused by alcohol, reducing the number of gram-negative bacteroidetes. Patescibacteria was tightly connected with the indicators of ALD. At the genus level, high-dose SFL significantly downregulated Akkermansia, Turicibacter, Alistipes and Ruminiclostridium, and improved the abundance of beneficial bacteria in Lactobacillus. In addition, Alistipes and Ruminiclostridium was closely connected with the indicators of ALD. CONCLUSION: Sea buckthorn fermentation liquid protected against alcoholic liver disease and modulated the composition of gut microbiota. © 2020 Society of Chemical Industry.

Arbuscular Mycorrhizal Fungi Enhance Sea Buckthorn Growth in Coal Mining Subsidence Areas in Northwest China.

Land subsidence induced by underground coal mining leads to severe ecological and environmental problems. Arbuscular mycorrhizal fungi (AMF) have the potential to improve plant growth and soil properties. We aimed to assess the effects of AMF on the growth and soil properties of sea buckthorn under field conditions at different reclamation times. Inoculation with AMF significantly promoted the survival rate of sea buckthorn over a 50-month period, while also increasing plant height after 14, 26, and 50 months. Crown width after 14 months and ground diameter after 50 months of inoculation treatment were significantly higher than in the uninoculated treatment. AMF inoculation significantly improved plant mycorrhizal colonization rate and promoted an increase in mycelial density in the rhizosphere soil. The pH and electrical conductivity of rhizosphere soil also increased after inoculation. Moreover, after 26 and 50 months the soil organic matter in the inoculation treatment was significantly higher than in the control. The number of inoculated soil rhizosphere microorganisms, as well as acid phosphatase activity, also increased. AMF inoculation may play an active role in promoting plant growth and improving soil quality in the long term and is conducive to the rapid ecological restoration of damaged mining areas.

High content analysis of sea buckthorn, black chokeberry, red and white currants microbiota - A pilot study.

The high potential of sea buckthorn, black chokeberry, red and white currants in healthy food industry boosted interest in the plant cultivation. The present study is the first work providing comprehensive information on microbial populations of these berries. Next Generation Sequencing allowed identification of eukaryotic and prokaryotic microorganisms prevalent on specific berries, including uncultivable microorganisms. Our study revealed the broad diversity of berries-associated bacterial and fungal microorganisms. Analysis of representative microbial OTUs showed a clear separation among inhabitants of sea buckthorn, black chokeberry and both currants, indicating plant-defined differences in the composition of the bacterial and fungal microbiota. Among the microorganisms distributed on tested berries, we documented potentially beneficial fungi and bacteria along with potential phytopathogens or those harmful for humans. Thus, plant microbiota appears to be highly relevant for the evaluation of the microbiota impact on food quality and human health.

Rhizospheric fungi and their link with the nitrogen-fixing Frankia harbored in host plant Hippophae rhamnoides L.

Sea buckthorn (Hippophae rhamnoides L.) is a pioneer plant used for land reclamation and an appropriate material for studying the interactions of symbiotic microorganisms because of its nitrogen-fixing root nodules and mycorrhiza. We used high-throughput sequencing to reveal the diversities and community structures of rhizospheric fungi and their link with nitrogen-fixing Frankia harbored in sea buckthorn collected along an altitude gradient from the Qinghai Tibet Plateau to interior areas. We found that the fungal diversities and compositions varied between different sites. Ascomycota, Basidiomycota, and Zygomycota were the dominant phyla. The distribution of sea buckthorn rhizospheric fungi was driven by both environmental factors and the geographic distance. Among all examined soil characteristics, altitude, AP, and pH were found to have significant (p < 0.05) effect on the rhizospheric fungal community. The rhizospheric fungal communities became more distinct as the distance increased. Moreover, co-inertia analysis identified significant co-structures between Frankia and AMF communities in the rhizosphere of sea buckthorn. We conclude that at the large scale, there are certain linkages between nitrogen-fixing bacteria and the AMF expressed in the distributional pattern.

Phylogeny and evolutionary genetics of Frankia strains based on 16S rRNA and nifD-K gene sequences.

16S rRNA and nifD-nifK sequences were used to study the molecular phylogeny and evolutionary genetics of Frankia strains isolated from Hippöphae salicifolia D. Don growing at different altitudes (ecologically classified as riverside and hillside isolates) of the Eastern Himalayan region of North Sikkim, India. Genetic information for the small subunit rRNA (16S rRNA) revealed that the riverside Frankia isolates markedly differed from the hillside isolates suggesting that the riverside isolates are genetically compact. Further, for enhanced resolutions, the partial sequence of nifD (3' end), nifK (5' end) and nifD-K IGS region have been investigated. The sequences obtained, failed to separate riverside isolates and hillside isolates, thus suggesting a possible role of genetic transfer events either from hillside to riverside or vice versa. The evolutionary genetic analyses using evogenomic extrapolations of gene sequence data obtained from 16S rRNA and nifD-K provided differing equations with the pace of evolution being more appropriately, intermediate. Values of recombination frequency (R), nucleotide diversity per site (Pi), and DNA divergence estimates supported the existence of an intermixed zone where spatial isolations occurred in sync with the temporal estimates. J. Basic Microbiol. 2015, 54, 1-9.

[Effect of afforestation modes on soil microbial community and nitrogen functional genes in Hippophae rhamnoides plantation].

The study aimed to assess the effect of different afforestation modes on microbial composition and nitrogen functional genes in soil. Soil samples from a pure Hippophae rhamnoides stand (SS) and three mixed stands, namely, H. rhamnoides and Pinus tabuliformis (SY), H. rhamnoides and Platycladus orientalis (SB), H. rhamnoides and Robinia pseucdoacacia (SC) were selected. The results showed that the total PLFA (TPLFA), bacterial PLFA, gram positive bacterial PLFA (G⁺PLFA) were significantly higher in soil samples from other three stands than those of the pure one. However, no significant difference was found for fungal PLFA among them. The abundance of nifH, amoA, nirK and narG genes were higher in SY and SC than in SS. The TPLFA, G⁺PLFA, gram negative bacterial PLFA (G⁻PLFA), and all of the detected gene abundance were significantly and positively correlated with soil pH, total organic carbon, total nitrogen, ammonium nitrogen and available potassium. Afforestation modes affected indirectly soil microbial composition and functional genes through soil properties. Mixing P. tabuliformis or P. orientalis with H. rhamnoides might be suitable afforestation modes, which might improve soil quality.

Micromonospora is a normal occupant of actinorhizal nodules.

Actinorhizal plants have been found in eight genera belonging to three orders (Fagales, Rosales and Cucurbitales). These all bear root nodules inhabited by bacteria identified as the nitrogen-fixing actinobacterium Frankia. These nodules all have a peripheral cortex with enlarged cells filled with Frankia hyphae and vesicles. Isolation in pure culture has been notoriously difficult, due in a large part to the growth of fast-growing contaminants where, it was later found, Frankia was slow-growing. Many of these contaminants, which were later found to be Micromonospora, were obtained from Casuarina and Coriaria. Our study was aimed at determining if Micromonospora were also present in other actinorhizal plants. Nodules from Alnus glutinosa, Alnus viridis, Coriaria myrtifolia, Elaeagnus x ebbingei, Hippophae rhamnoides, Myrica gale and Morella pensylvanica were tested and were all found to contain Micromonospora isolates. These were found to belong to mainly three species: Micromonospora lupini, Micromonospora coriariae and Micromonospora saelicesensis. Micromonospora isolates were found to inhibit some Frankia strains and to be innocuous to other strains.

Response pattern of amino compounds in phloem and xylem of trees to soil drought depends on drought intensity and root symbiosis.

This study aimed to identify drought-mediated differences in amino nitrogen (N) composition and content of xylem and phloem in trees having different symbiotic N(2)-fixing bacteria. Under controlled water availability, 1-year-old seedlings of Robinia pseudoacacia (nodules with Rhizobium), Hippophae rhamnoides (symbiosis with Frankia) and Buddleja alternifolia (no such root symbiosis) were exposed to control, medium drought and severe drought, corresponding soil water content of 70-75%, 45-50% and 30-35% of field capacity, respectively. Composition and content of amino compounds in xylem sap and phloem exudates were analysed as a measure of N nutrition. Drought strongly reduced biomass accumulation in all species, but amino N content in xylem and phloem remained unaffected only in R. pseudoacacia. In H. rhamnoides and B. alternifolia, amino N in phloem remained constant, but increased in xylem of both species in response to drought. There were differences in composition of amino compounds in xylem and phloem of the three species in response to drought. Proline concentrations in long-distance transport pathways of all three species were very low, below the limit of detection in phloem of H. rhamnoides and in phloem and xylem of B. alternifolia. Apparently, drought-mediated changes in N composition were much more connected with species-specific changes in C:N ratios. Irrespective of soil water content, the two species with root symbioses did not show similar features for the different types of symbiosis, neither in N composition nor in N content. There was no immediate correlation between symbiotic N fixation and drought-mediated changes in amino N in the transport pathways.

Effect of chitinase on resistance to fungal pathogens in sea buckthorn, Hippophae rhamnoides, and cloning of Class I and III chitinase genes.

Sea buckthorn (Hippophae rhamnoides L.) is naturally distributed from Asia to Europe. It has been widely planted as an ornamental shrub and is rich in nutritional and medicinal compounds. Fungal pathogens that cause diseases such as dried-shrink disease are threats to the production of this plant. In this study, we isolated the dried-shrink disease pathogen from bark and total chitinase protein from leaves of infected plants. The results of the Oxford Cup experiment suggested that chitinase protein inhibited the growth of this pathogen. To improve pathogen resistance, we cloned chitinase Class I and III genes in H. rhamnoides, designated Hrchi1 and Hrchi3. The full-length cDNA of the open reading frame region of Hrchi1 contained 903 bp encoding 300 amino acids and Hrchi3 contained 894 bp encoding 297 amino acids. Active domain analysis, protein types, and secondary and 3D structures were predicted using online software.

Diversity of Frankia strains nodulating Hippophae salicifolia D. Don using FAME profiling as chemotaxonomic markers.

Twelve Frankia strains isolated from Hippophae salicifolia D. Don or Alnus glutinosa or Comptonia peregrine, showed the significant variation in fatty acid composition viz. palmitic acid (16:0), oleic acid (18:1), linoleic acid (18:2), linolenic acid (18:3), arachidic acid (20:0) and erucic acid (22:1) suggesting the strain specific variability among the Frankia strains. Presence of Erucic acid (22:1), a major component of the oil obtained from the seeds of Brassica sp., albeit in lesser amount in the few studied frankial strains, is the first report. Cluster analysis on the basis of fatty acid composition suggests the presence of two distinct clusters with similitude coefficient ranging from 0.75 to 1.00. Cluster I with HsIi2 showed great divergence from other 11 frankial strains (Cluster II). The two sub groups were distinguished in cluster II: IIa contained five strains isolated from H. salicifolia and these strains are distantly related to the strains of cluster IIb isolated from different host. There is high degree of similarity among the frankial strains of Cluster IIb which suggests that the frankial strains might be evolved from the same ancestor. FAME profiling might be useful tool in the study of polyphasic approach based taxonomy and phylogenetic relationship.

Cold-adapted and rhizosphere-competent strain of Rahnella sp. with broad-spectrum plant growth-promotion potential.

A phosphate-solubilizing bacterial strain isolated from Hippophae rhamnoides rhizosphere was identified as Rahnella sp. based on its phenotypic features and 16S rRNA gene sequence. The bacterial strain showed the growth characteristics of a cold-adapted psychrotroph, with the multiple plant growth-promoting traits of inorganic and organic phosphate solubilization, 1-aminocyclopropane-1- carboxylate-deaminase activity, ammonia generation, and siderophore production. The strain also produced indole- 3-acetic acid, indole-3-acetaldehyde, indole-3-acetamide, indole-3-acetonitrile, indole-3-lactic acid, and indole-3- pyruvic acid in tryptophan-supplemented nutrient broth. Gluconic, citric and isocitric acids were the major organic acids detected during tricalcium phosphate solubilization. A rifampicin-resistant mutant of the strain exhibited high rhizosphere competence without disturbance to the resident microbial populations in pea rhizosphere. Seed bacterization with a charcoal-based inoculum significantly increased growth in barley, chickpea, pea, and maize under the controlled environment. Microplot testing of the inoculum at two different locations in pea also showed significant increase in growth and yield. The attributes of coldtolerance, high rhizosphere competence, and broad-spectrum plant growth-promoting activity exhibited the potential of Rahnella sp. BIHB 783 for increasing agriculture productivity.

[Characterization of soil microbial community function and structure in rhizosphere of typical tree species and the meaning for environmental indication in the Loess Plateau].

Determination of the soil microbial community structure in rhizosphere of typical tree species in the Loess Plateau can be of great theoretical significance for correctly assessing the characteristics of soil ecological rehabilitation of the Loess Plateau. In this study,spore density analysis, microbial cultivation and BIOLOG were employed to evaluate the AMF spore density and soil microbial community diversity under four tree species with vesicular-arbuscular mycorrhizae in ecological rehabilitation area of the Loess Plateau, north Shaanxi Province. The results show that the different tree species differed significantly in both soil microbial number and microbial functional diversity, AMF spore density of Hippophae rhamnoides soil is 2.24 times than that of the Robinia pseudoacacia soil,and the rank as following order: Hippophae rhamnoides > Sophora viciifolia > Caragana microphylla > Robinia pseudoacacia . The statistical significant are detected in the bacteria and actinomyces numbers, however, there is no statistical significance in fungi number among the treatments. The principle component analyses indicates that scatter of Caragana microphylla and Hippophae rhamnoides are smaller than that of Sophora viciifolia and Robinia pseudoacacia, these results suggest that the soil community structure strongly varied among the different tree species. Numbers of carbon sources related to the first two components are 14 and 8. Correlation analysis shows that the AMF spore density appeared extremely significantly and positively correlated with the number of bacteria,and the metabolic of amino acids,amines and aromatic compounds, respectively. Moreover,AMF spore density positively correlated with the average well color development (AWCD), nevertheless, no correlations are found among AMF spore density, carboxylic acids,carbohydrates and polymers. These results suggest that AMF spore density is shown to be an important environmental biology parameter used in correctly assessing the soil bacteria metabolic community and diversity under the tree species in ecological rehabilitation of the Loess Plateau, north Shaanxi Province.

Plant growth-promoting and rhizosphere-competent Acinetobacter rhizosphaerae strain BIHB 723 from the cold deserts of the Himalayas.

A phosphate-solubilizing bacterial strain BIHB 723 isolated from the rhizosphere of Hippophae rhamnoides was identified as Acinetobacter rhizosphaerae on the basis of phenotypic characteristics, carbon source utilization pattern, fatty acid methyl esters analysis, and 16S rRNA gene sequence. The strain exhibited the plant growth-promoting attributes of inorganic and organic phosphate solubilization, auxin production, 1-aminocyclopropane-1-carboxylate deaminase activity, ammonia generation, and siderophore production. A significant increase in the growth of pea, chickpea, maize, and barley was recorded for inoculations under controlled conditions. Field testing with the pea also showed a significant increment in plant growth and yield. The rifampicin mutant of the bacterial strain effectively colonized the pea rhizosphere without adversely affecting the resident microbial populations.

Influence of iron and chelator on siderophore production in Frankia strains nodulating Hippophae salicifolia D. Don.

Effect of iron and chelator on the growth and siderophore production in the ten newly Frankia strains isolated from the root nodules of Hippophae salicifolia D. Don and the two reference strains were studied. Growth of the strains was greatly affected when grown in the iron and EDTA deprived conditions. All the strains were capable of producing both the hydroxamate and catecholate type siderophore that was detected using the Csaky and Arnow assays. Production of siderophore was enhanced in the EDTA replenish condition in contrast to the iron supplemented medium suggesting that EDTA reduces the availability of other free metals and hence creates the stress condition for which the secretion of siderophore is enhanced. A decrease in siderophore production was observed with an increase in iron concentration. Strains HsIi2 and HsIi10 were found to be producing more siderophore than the other strains.