Ipomoea obscura Represents a New Host of Phytoplasma Belonging to 16SrII Group Associated with Witches'-Broom Symptoms in China.

Phytoplasmas are phloem-limited plant pathogenic prokaryotes which can not be cultured in vitro. The pathogens could cause various plant symptoms such as witches'-broom, virescence, and leaf yellows. Ipomoea obscura is a valuable plant species belonging to the family Convolvulaceae, mainly used as a traditional Chinese medicine used to treat diseases such as dehydration and diuresis. In western countries it is commonly referred to as 'obscure morning glory'. During 2020 to 2021, plants showing abnormal symptoms including witches'-broom, internode shortening, and small leaves were found in Hainan Province, a tropical island of China. Approximately 30 % of I. obscura plants in the sampling regions which spanned 400 acres, showed symptoms. In order to identify the associated pathogen, six symptomatic samples and three asymptomatic samples were collected and total DNA were extracted from 0.10 g fresh plant leaf tissues using CTAB DNA extraction method. 16S rRNA and secA gene fragments, specific to phytoplasmas, were PCR amplified using primers R16mF2/R16mR1 and secAfor1/secArev3. The target PCR bands were obtained from the DNA of six symptomatic samples, whereas not from the DNA of the asymptomatic samples. The PCR products of phytoplasma 16S rRNA and secA gene obtained from the diseased samples were cloned and sequenced by Biotechnology (Shanghai) Co., Ltd. (Guangzhou, China). The 16S rRNA and secA gene sequences identified in the study were all identical with the length of 1330 bp (GenBank accession: OR625212) and 720 bp (OR635662) respectively. According to methods and protocols of phytoplasma identification and classification (Wei and Zhao, 2022), the phytoplasma strain identified in the study was described as Ipomoea obscura witches'-broom (IoWB) phytoplasma, IoWB-hnld strain. The partial 16S rRNA gene sequence of IoWB showed 100 % sequence identity over the full 1330 bp sequence to phytoplasmas belonging to 16SrII group like cassava witches'-broom phytoplasma (KM280679). The BLAST search of the 720 bp partial secA gene fragment of IoWB showed 100% sequence identity for the full sequence to phytoplasmas belonging to 16SrII group like 'Sesamum indicum' phyllody phytoplasma (OQ420657). RFLP analysis based on the 16S rRNA gene using iPhyClassifier demonstrated that the IoWB strain was a member of 16SrII-A subgroup with the similarity coefficient 1.00 to the reference phytoplasma strain (L33765). Phylogenetic analysis based on 16S rRNA and secA genes by MEGA 7.0 employing neighbor-joining (NJ) method with 1000 bootstrap value indicated that IoWB-hnld was clustered into one clade with the phytoplasmas belonging to 16SrII group, with 98% and 100% bootstrap value separately. To our knowledge, this is the first report that Ipomoea obscura can be infected by phytoplasmas belonging to 16SrII-A subgroup in China. This report adds to the host range of 'Ca. Phytoplasma aurantifolia', documenting the symptoms on I. obscura which will assist in monitoring and control of the associated pathogen.

First Report of 16SrII Group Related Phytoplasma Associated with Areca Palm Yellow Leaf Disease on Areca catechu in China.

The areca palm, Areca catechu L., family Arecaceae is an important herbal medicine which has potential for the treatment of parasitic diseases, digestive function disorders and depression (Peng et al. 2015). Yellow leaf disease (YLD), caused by phytoplasma, is a destructive disease of Areca catechu. In 1981, the YLD was first discovered in Tunchang, Hainan, China. According to the investigation in 2020, the occurrence area of YLD was 32 102.38 hm2 in Hainan, China, resulting in 50%-60% yield loss. Previous researchers based on 16S rDNA gene PCR amplification analysis showed that YLD in Hainan was caused by 16SrI group phytoplasma (Che et al. 2010). In August, 2022, yellow leaf symptoms were observed on middle and lower leaves of Areca catechu. Forty symptomatic plants and three asymptomatic samples were collected in Wenchang, Hainan, China (19°33'9″N, 110°48'5″E). Forty-three samples (0.1g each) were used to extract total DNA (TIANGEN plant genomic DNA extraction kit). Phytoplasma universal primers named P1/P7 (Schneider et al. 1995) and R16F2n/R16R2 (Gundersen and Lee 1996) for 16Sr DNA and primers named fTuf1/rTuf1 and fTufu/rTufu (Schneider et al. 1997) for tuf genes were used for amplifying phytoplasma sequences from isolated DNA samples by nested PCR. No fragment was amplified in asymptomatic plants and four out of forty symptomatic samples could amplify target fragment. R16F2n/R16R2 amplicons (1 248 bp) and fTufu/rTufu amplicons (845 bp) from four symptomatic Areca catechu samples were sequenced in BGI (https://genomics.cn/). The 16Sr DNA GenBank accession numbers of four positive strains (named HNWC5, HNDZ1, HNDZ3 and HNDZ6) were OQ586072, OQ586085, OQ586086, OQ586087, respectively and the tuf GenBank accession numbers were OQ595209, OQ595210, OQ595211, OQ595212, respectively. Sequence alignment showed that the 16S rDNA and tuf sequence of HNDZ1, HNDZ3 and HNDZ6 were 100% consistent. 16S rDNA of HNWC5 was 99.96% consistent with HNDZ1 and tuf of HNWC5 was 98.31% consistent with HNDZ1. Interestingly, blast search based on 16S rDNA gene of HNWC5 showed 100% sequence identity with that of 16SrII group phytoplasma such as 'Eclipta prostrata' phytoplasma strain Ep1(MH144204.1), 'Aeschynomene americana' phytoplasma isolate AA1(MH231157.1) and 'Acacia confusa' witches'-broom phytoplasma isolate HK6(ON408364.1). Blast search based on tuf gene of HNWC5 showed 98.7% sequence identity with that of bamboo witches'-broom phytoplasma (FJ853160.1) and 91.02% sequence identity with that of 'podocarpus nagi' fasciation phytoplasma (KR633146) and 90.78% sequence identity with that of 'Musa acuminata' elephantiasis disease phytoplasma (MF983708). The phylogenetic tree was constructed based on 16Sr DNA gene by MEGA 7.0 employing neighbor-joining (NJ) method with 1000 bootstrap value (Kumar et al. 2016). The result indicated that the HNWC5, HNDZ1, HNDZ3 and HNDZ6 phytoplasma strains clustered a subclade in 16SrII group. The virtual RFLP analysis based on the 16Sr DNA gene sequence was performed by the online phytoplasma classification tool iPhyClassifier (Zhao et al. 2009) using restriction endonucleases of AluI, BamHI, BfaI, BstUI, DraI, EcoRI, HaeIII, HhaI, HinfI, HpaI, HpaII, KpnI, Sau3AI, MseI, RsaI, SspI and TaqI. The result indicated that HNWC5 was most similar to the reference pattern of peanut witches'-broom phytoplasma (16SrII-A subgroup, GenBank accession: L33765) and the pattern similarity coefficient of HNWC5 is 1.00. However, the HpaII restriction endonuclease pattern of HNDZ1, HNDZ3 and HNDZ6 was different from L33765 and the similarity coefficient was 0.97, which indicated this strain may represent a new subgroup within the 16SrII group. To our knowledge, this is the first report of 16SrII group related phytoplasma associated with YLD on Areca catechu in China. Our study contributes to understanding the polymorphism of phytoplasma causing YLD and provides an important reference for pathogen specific detection.

First Report of 16SrI-B Subgroup Related Phytoplasma Associated with Yellows Symptoms of Rubus cochinchinensis in China.

Rubus cochinchinensis, an important traditional Chinese medicine in China is used to treat rheumatic arthralgia, bruises and lumbocrural pain (He et al.2005). In January 2022, yellow leaves of R. cochinchinensis were found in Tunchang City, Hainan Province, a tropical island in China. Chlorosis spread along the direction of vascular tissue while the leaf veins remain green (Fig. 1). In addition, the leaves were slightly shrunken and the growth vigor is poor (Fig. 1). By survey, we found the incidence of this disease was about 30%. Three etiolated samples and three healthy samples (0.1g each) were used to extract total DNA (TIANGEN plant genomic DNA extraction kit). Using nested PCR method, phytoplasma universal primers P1 / P7 (Schneider et al., 1995) and R16F2n / R16R2 (Lee et al. 1993) were used to amplified phytoplasma 16S rDNA gene. Primers rp F1 / R1 (Lee et al. 1998) and rp F2 / R2 (Martini et al. 2007) were used to amplified rp gene. 16S rDNA gene and rp gene fragments were amplified from three leaf etiolated samples, but not from healthy samples. The amplified fragments were cloned and sequenced, and the sequences were assembled by DNASTAR11. By sequence alignment, we found the obtained 16S rDNA and rp gene sequences of three leaf etiolated samples were same. The length of 16S rDNA fragment was 1237 bp (accession number: ON944105) and the length of rp gene fragment was 1212 bp (accession number: ON960069). The phytoplasma strain was named as 'R. cochinchinensis' yellows leaf phytoplasma (RcT), RcT-HN1 strain. The 16S rDNA gene sequence of RcT-HN1is 99.8% consistent with 16SrI-B subgroup members such as the 'Brassica napus' dwarf phytoplasma strain WH3 (MG599470.1), Chinaberry yellows phytoplasma strain LJM-1(KX683297.1) and Arecanut yellow leaf disease phytoplasma strain B165 (FJ694685.1). The rp gene sequence of RcT-HN1 is 100% consistent with rpI-B subgroup members such as the 'Salix tetradenia' witches'-broom phytoplasma strain YM-1 (KC117314.1) and Chinaberry witches'-broom phytoplasma strain Hainan (EU348781.1). The phylogenetic tree analysis, based on concatenated 16S rDNA-rp gene sequence of same group phytoplasma by MEGA 7.0 employing neighbor-joining (NJ) method with 1000 bootstrap value, were performed (Kumar et al., 2016). The results showed that RcT-HN1 phytoplasma strain formed a subclade in aster yellows group B subgroup (Fig. 2). The virtual RFLP analysis based on the 16S rRNA gene fragment of RcT-HN1 phytoplasma strain was performed by the interactive online phytoplasma classification tool iPhyClassifier (Zhao et al., 2009). The results showed that the phytoplasma strain was same as the reference pattern of the onion yellows phytoplasma of 16SrI-B (GenBank accession: AP006628), and the similarity coefficient was 1.00. This is the first report that 16SrI-B subgroup related phytoplasma infected R. cochinchinensis and caused yellows symptoms in China. The discovery of the disease is helpful to the study of the spread of phytoplasma-related diseases and protect R. cochinchinensis resources.

Long-term remote observations of particulate organic phosphorus concentration in eutrophic Lake Taihu based on a novel algorithm.

Monitoring the long-term spatiotemporal variations in particulate organic phosphorus concentration (CPOP) is imperative for clarifying the phosphorus cycle and its biogeochemical behavior in waters. However, little attention has been devoted to this owing to a lack of suitable bio-optical algorithms that allow the application of remote sensing data. In this study, based on Moderate Resolution Imaging Spectroradiometer (MODIS) data, a novel absorption-based algorithm of CPOP was developed for eutrophic Lake Taihu, China. The algorithm yielded a promising performance with a mean absolute percentage error of 27.75% and root mean square error of 21.09 µg/L. The long-term MODIS-derived CPOP demonstrated an overall increasing pattern over the past 19 years (2003-2021) and a significant temporal heterogeneity in Lake Taihu, with higher value in summer (81.97 ± 3.81 µg/L) and autumn (82.07 ± 3.8 µg/L), and lower CPOP in spring (79.52 ± 3.81 µg/L) and winter (78.74 ± 3.8 µg/L). Spatially, relatively higher CPOP was observed in the Zhushan Bay (85.87 ± 7.5 µg/L), whereas the lower value was observed in the Xukou Bay (78.95 ± 3.48 µg/L). In addition, significant correlations (r > 0.6, P < 0.05) were observed between CPOP and air temperature, chlorophyll-a concentration and cyanobacterial blooms areas, demonstrating that CPOP was greatly influenced by air temperature and algal metabolism. This study provides the first record of the spatial-temporal characteristics of CPOP in Lake Taihu over the past 19 years, and the CPOP results and regulatory factors analyses could provide valuable insights for aquatic ecosystem conservation.

Long-term dynamics and drivers of particulate phosphorus concentration in eutrophic lake Chaohu, China.

Particulate phosphorus (PP) plays an important biological role in the eutrophication process, and is thus an important water quality parameter for assessing climatic change and anthropogenic activity factors that affect aquatic ecosystems. Here, we used 20-year Moderate Resolution Imaging Spectroradiometer (MODIS) data to explore the patterns and trends of PP concentration (CPP) in eutrophic Lake Chaohu based on a new empirical model. The validation results indicated that the developed model performed satisfactorily in estimating CPP, with a mean absolute percentage error of 31.89% and root mean square error of 0.022 mg/L. Long-term MODIS observations (2000-2019) revealed that the CPP of Lake Chaohu has experienced an overall increasing trend and distinct spatiotemporal heterogeneity. The driving factor analysis revealed that the chemical fertilizer consumption, municipal wastewater, industrial sewage, precipitation, and air temperature were the five potential driving factors and collectively explained more than 81% of the long-term variation in CPP. This study provides the long-term datasets of CPP in inland waters and new insights for future water eutrophication control and restoration efforts.

Effect of pistachio shell as a carbon source to regulate C/N on simultaneous removal of nitrogen and phosphorus from wastewater.

Acid-pretreated pistachio shells were used as carbon sources to investigate the effects of carbon source dosage on simultaneous nitrogen and phosphorus removal under different carbon/nitrogen (C/N) ratios (7, 9, and 11). Results showed that C/N was positively correlated with mixed liquor suspended solids (MLSS) (R2 = 0.998, p < 0.01) and f value (R2 = 0.975, p < 0.05). Moreover, it was negatively correlated with the sludge volume index (SVI) (R2 =  - 0.959, p < 0.05). C/N was also significantly negatively related to chemical oxygen demand removal rate (R2 =  - 0.986, p < 0.05) and positively related to ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) removal rate (p < 0.05), the correlation coefficients were 0.992, 0.990 and 0.994, respectively. In the reactor with C/N of 11, the MLSS concentration and f value were the highest, the SVI was the lowest, and the removal efficiencies of NH4+-N (85.49 % ± 1.96 %), TN (84.19 % ± 1.42 %) and TP (94.10 % ± 1.67 %) were the highest. Furthermore, the relative abundance of denitrifying bacteria was the highest in the reactor. The abundance of nitrifying bacteria and phosphorus-removal bacteria was also relatively high.

Study on performance of carbon source released from fruit shells and the effect on biological denitrification in the advanced treatment.

In order to solve the problem of shortage of carbon source for biological denitrification in advanced treatment of the effluent from secondary treatment of sewage, five kinds of fruit shells (pistachio shell, peanut shell, ginkgo shell, walnut shell and hazelnut shell) were preliminarily selected from eight kinds of fruit shells for experiments of static carbon release and denitrification. The carbon release performance (amount and law of carbon release and biodegradability of released carbon) and denitrification performance of different shells were investigated. Results showed that the peanut shell had the largest amount of carbon release (0.88 mg chemical oxygen demand [COD] g-1) and the highest removal rate of nitrate (NO3--N) (76.48% ± 4.06%). However, the released carbon could not be fully utilized by denitrifying bacteria, resulting in a (205.90% ± 59.49%) increase in effluent COD compared with influent. The amounts of carbon release of ginkgo nut shell, walnut shell, and hazelnut shell were low (0.45, 0.41, and 0.43 mg COD g-1, respectively). The released carbon could not be used easily by microorganisms. Meanwhile, the contents of degradable aromatic protein and protein-like in dissolved organic matter (DOM) were low. Even the fulvic acid-like with low biodegradability also appeared in the soaking solution of the hazelnut shell. The NO3--N and total nitrogen aveage removal rates were low in these three fruit shells and showed the removals within the 54.10-57.25% range and 52.21%-54.24% range, respectively. The amount of carbon release of pistachio shell was lower than that of peanut shell. However, the released carbon of the former was more biodegradable than that of the latter. Moreover, the relative molecular mass of DOM was small, and the contents of aromatic protein and protein-like were much higher than those of the four other kinds of fruit shells. The NO3--N removal rate (71.48% ± 0.98%) of pistachio shell was only slightly lower than that of peanut shell. In conclusion, pistachio shell was the best carbon source for biological denitrification in the advanced treatment.

Simulation of the Parameters Effecting the Water Quality Evolution of Xuanwu Lake, China.

After years of water environment improvement, China's water quality has improved to some extent in recent years. However, different water areas have different characteristics of water pollution. The paper used mathematical models to investigate the influence of different parameters on the water quality of Xuanwu Lake, China. The predominant focus was on the nutrients concentration due to changing the amount of pollutants, degradation coefficient, water diversion discharge and diffusion coefficient. The results showed that the amount of pollutants had the most significant impact, followed by the degradation coefficient. The total phosphorus and total nitrogen concentrations of Xuanwu Lake increased with the increase of the amount of pollutants. The water quality of Xuanwu Lake decreased significantly with the increase of degradation coefficient. Increasing the water diversion discharge will not only make a big difference in water quality, but it will also worsen the water quality. The effect of the amount of pollutants on Xuanwu Lake total phosphorus and total nitrogen is 4.1 and 5.7 times that of water diversion discharge. The influence of total phosphorus and total nitrogen in the degradation coefficient scheme is 3.5 and 6.2 times that of the water diversion discharge scheme. The diffusion coefficient has almost no effect on the water quality of Xuanwu Lake. From the practical difficulty and implementation effect of water environment improvement, the order of water quality improvement effect from good to bad is as follows: the amount of pollutants scheme, degradation coefficient scheme, water diversion scheme, diffusion coefficient scheme. Under the circumstance of limited water diversion, the lake will effectively improve the water quality. Reducing the discharge of pollutants is the fundamental measure to control water environment problems, and water diversion is an auxiliary measure to improve the water ecology. It will become a trend to combine the reduction of pollutant discharge and water transfer for water environment improvement. This paper is of significance for improving the water quality of Xuanwu Lake, and it also provides a scientific method for water environment improvement of water diversion projects.

Molecular Mechanism of Palmitic Acid on Myocardial Contractility in Hypertensive Rats and Its Relationship with Neural Nitric Oxide Synthase Protein in Cardiomyocytes.

OBJECTIVE: It is aimed at investigating the mechanism of palmitic acid (PA) on myocardial contractility in hypertensive rats and its relationship with myocardial neural nitric oxide synthase (nNOS) protein. METHODS: The rats were randomly divided into sham operation group and hypertensive group, with thirty rats in each group, to prepare angiotensin II-induced hypertensive model rats. The blood pressure of rats was measured by the multianimal multichannel tail cuff noninvasive blood pressure system of Kent Coda, USA. The Ionoptix single-cell contraction detection system was used to detect myocardial cells. ATP level of left ventricular cardiomyocytes was determined by luminescence method, and protein was measured by Western blot. RESULTS: Compared with the sham group, systolic blood pressure and diastolic blood pressure were increased in the hypertensive group over 4 weeks; PA increased the contractility of left ventricular cardiomyocytes in normal rats, but not in hypertensive rats, and PA increased the intracellular ATP level of rats in the sham group but not in the hypertension group. In the hypertension group, the expression of nNOS in the cardiomyocytes was significantly increased, and specific nNOS inhibitor S-methyl-L-thiocitrulline (SMTC) was found to restore the positive inotropic effect of PA in the myocardium of the hypertension group. PA was supplemented after using CPT-1 inhibitor etomoxir (ETO); it was found that ETO inhibited the positive inotropic effect of PA on left ventricular cardiomyocytes in the sham group, and PA was supplemented after using SMTC and ETO, it was found that SMTC + ETO could inhibit the positive inotropic effect of PA on left ventricular cardiomyocytes in myocardium of hypertensive rats. CONCLUSION: PA could increase the contractility of healthy cardiomyocytes, but had no obvious positive effect on the cardiomyocytes of hypertensive rats, PA enhanced the contractility of cardiomyocytes by increasing ATP level in them, and the inhibitory effect of PA on myocardial contractility in hypertensive rats may be related to the increased nNOS and CPT-1 in cardiomyocytes.

Transcriptomic Analysis of Marine Gastropod Hemifusus tuba Provides Novel Insights into Conotoxin Genes.

The marine gastropod Hemifusus tuba is served as a luxury food in Asian countries and used in traditional Chinese medicine to treat lumbago and deafness. The lack of genomic data on H. tuba is a barrier to aquaculture development and functional characteristics of potential bioactive molecules are poorly understood. In the present study, we used high-throughput sequencing technologies to generate the first transcriptomic database of H. tuba. A total of 41 unique conopeptides were retrieved from 44 unigenes, containing 6-cysteine frameworks belonging to four superfamilies. Duplication of mature regions and alternative splicing were also found in some of the conopeptides, and the de novo assembly identified a total of 76,306 transcripts with an average length of 824.6 nt, of which including 75,620 (99.1%) were annotated. In addition, simple sequence repeats (SSRs) detection identified 14,000 unigenes containing 20,735 SSRs, among which, 23 polymorphic SSRs were screened. Thirteen of these markers could be amplified in Hemifusus ternatanus and seven in Rapana venosa. This study provides reports of conopeptide genes in Buccinidae for the first time as well as genomic resources for further drug development, gene discovery and population resource studies of this species.

Research on Water Environment Regulation of Artificial Playground Lake Interconnected Yangtze River.

With the rapid development of China, water pollution is still a serious problem despite implementation of control measures. Reasonable water environment management measures are very important for improving water quality and controlling eutrophication. In this study, the coupled models of hydrodynamics, water quality, and eutrophication were used to predict artificial Playground Lake water quality in the Zhenjiang, China. Recommended "unilateral" and "bilateral" river numerical models were constructed to simulate the water quality in the Playground Lake without or with water diversion by pump, sluice and push pump. Under "unilateral" and "bilateral" river layouts, total nitrogen and total phosphorus meet the landscape water requirement through water diversion. Tourist season in spring and summer and its suitable temperature result in heavier eutrophication, while winter is lighter. Under pumping condition, water quality and eutrophication of "unilateral" river is better than "bilateral" rivers. Under sluice diversion, the central landscape lake of "unilateral river" is not smooth, and water quality and eutrophication is inferior to the "bilateral". When the water level exceeds the flood control level (4.1 m), priority 1 is launched to discharge water from the Playground Lake. During operation of playground, when water level is less than the minimum level (3.3 m), priority 2 is turned on for pumping diversion or sluice diversion to Playground Lake. After opening the Yangtze river diversion channel sluice, priority 3 is launched for sluice diversion to the Playground Lake. When the temperature is less than 15 °C, from 15 °C to 25 °C and higher than 25 °C, the water quality can be maintained for 15 days, 10 days and 7 days, respectively. Corresponding to the conditions of different priority levels, reasonable choices of scheduling measures under different conditions to improve the water quality and control eutrophication of the Playground Lake. This article is relevant for the environmental management of the artificial Playground Lake, and similar lakes elsewhere.

Research on the Relationship between Water Diversion and Water Quality of Xuanwu Lake, China.

Water diversion is often used to improve water quality to reach the standard of China in the short term. However, this large amount of water diversion can not only improve the water quality, but also lead to a decline in the water quality (total phosphorus, total nitrogen) of Xuanwu Lake. Through theoretical analysis, the relationship between water quality and water diversion is established. We also found that the multiplication of the pollutant degradation coefficient (K) and the water residence time (T) is a constant (N), K⋅T=N. The water quality changed better at first, with the increase of inflow discharge, and then became worse, and the optimal water quality inflow discharge is 180,000 m³/day. By constructing two-dimensional hydrodynamic and water quality models, the optimal diversion water plan is calculated. Through model calculations, it can be seen that reducing the inflow discharge makes the water residence time longer (15.3 days changed to 23.8 days). Thereby, increasing the degradation of pollutants, and thus improving water quality. Compared with other wind directions, the southwest wind makes the water quality of Xuanwu Lake the most uniform. The concentration of water quality first became smaller and then became larger, as the wind speed increased, and eventually became constant. Implementing these results for water quality improvement in small and medium lakes will significantly reduce the cost of water diversion.

Effect of selenium-enriched organic material amendment on selenium fraction transformation and bioavailability in soil.

To exploit the plant byproducts from selenium (Se) biofortification and reduce environmental risk of inorganic Se fertilizer, pot experiment was conducted in this study. The effects of Se-enriched wheat (Triticum aestivum L.) straw (WS + Se) and pak choi (Brassica chinensis L.) (P + Se) amendment on organo-selenium speciation transformation in soil and its bioavailability was evaluated by pak choi uptake. The Se contents of the cultivated pak choi in treatments amended with the same amount of Se-enriched wheat straw and pak choi were 1.7 and 9.7 times in the shoots and 2.3 and 6.3 times in the roots compared with control treatment. Soil respiration rate was significantly increased after all organic material amendment in soil (p < 0.05), which accelerated the mineralization of organic materials and thus resulted in soluble Se (SOL-Se), exchangeable Se (EX-Se), and fulvic acid-bound Se (FA-Se) fraction increasing by 25.2-29.2%, 9-13.8%, and 4.92-8.28%, respectively. In addition, both Pearson correlation and cluster analysis showed that EX-Se and FA-Se were better indicators for soil Se availability in organic material amendment soils. The Marquardt-Levenberg Model well described the dynamic kinetics of FA-Se content after Se-enriched organic material amendment in soil mainly because of the mineralization of organic carbon and organo-selenium. The utilization of Se in P + Se treatment was significantly higher than those in WS + Se treatment because of the different mineralization rates and the amount of FA-Se in soil. Se-enriched organic materials amendment can not only increase the availability of selenium in soil but also avoid the waste of valuable Se source.

Effects of melanin from Sepiella Maindroni ink (MSMI) on the intestinal Microbiome of mice.

BACKGROUND: By the search for new natural compounds with beneficial health effects, cephalopod ink has been considered as an attempt to develop new drugs and functional foods, which is an especially active field in Asia, where cephalopods are a major fishery catch, for which ink sacs are a bi-product and where homeopathic medicine has deep roots. There is a demand to evaluate the safety and influence to the organism. The specific composition and relative abundance of the gut microbiota, which is potentially a major modulator of host metabolism, drives the interaction between functional foods and host health. We explore the effects of melanin from Sepiella Maindroni, most common cuttlefish in China, on the intestinal microbiome of mice. RESULTS: ICR mice were randomly divided four groups, which were normal group (S), low melanin dose group (D; 120 mg/kg), medium melanin dose group (Z; 240 mg/kg), and high melanin dose group (G; 480 mg/kg). Melanin was delivered for 28 consecutive days. Fecal samples were used to generate 7715 operational taxonomic units (OTUs) via high-throughput sequencing. There were significant shifts in relative abundance of the dominant taxa at the phylum, class, order, family, and genus levels following melanin treatment. CONCLUSIONS: MSMI had no significant effect on the structure of intestinal flora in mice. The main effect was in the proportion of dominant bacterial communities. The effect positively correlated with the dose. From a health point of view, the use of melanin does not cause intestinal flora disorder. Our results may have important implications for MSMI as functional food component and potential therapeutic for manipulating gut microbiota.

Characterization and functional analysis of a novel C-type lectin from the swimming crab Portunus trituberculatus.

C-type lectins (CTLs) are a family of calcium-dependent carbohydrate-binding proteins. In the present study, a novel C-type lectin (designated as PtCTL1) was identified and characterized from Portunus trituberculatus. The full-length cDNA of PtCTL1 was of 702 bp, containing a 5' untranslated region (UTR) of 91 bp, a 3' UTR of 110 bp with a poly (A) tail, and an open reading frame (ORF) of 501 bp encoding a polypeptide of 166 amino acids with a putative signaling peptide of 21 amino acids. A C-type lectin carbohydrate-recognition domain (CRD) containing four conserved cysteines was identified in the amino acid sequence of PtCTL1. The cDNA fragment encoding the mature peptide of PtCTL1 was recombined into pET-21a(+) with a C-terminal hexa-histidine tag fused in-frame and expressed in Escherichia coli Origami (DE3). The recombinant PtCTL1 (rPtCTL1) can agglutinate all the tested bacteria, including three Gram-positive bacterial strains and three Gram-negative bacterial strains. In addition, erythrocyte agglutination and LPS-binding activity were observed in a Ca2+-dependent manner. The erythrocyte agglutination was inhibited by EDTA, indicating that PtCTL1 was Ca2+-dependent. The mRNA transcripts of PtCTL1 were detected mainly in the tissues of hepatopancreas and hemocytes and its levels were significantly up-regulated in hemocytes following Vibrio alginolyticus challenge. These results indicate that PtCTL1 may function as a pattern recognition receptor (PRR) for protecting P. trituberculatus from bacterial infection. Moreover, such findings also provide evidence for further understanding the innate immunology of invertebrate.

[Effects of Nitrogen Application on Selenium Uptake, Translocation and Distribution in Winter Wheat].

In order to better understand the effects of nitrogen application on accumulation, translocation and distribution of selenium in winter wheat and to provide theoretical reference for reasonable nitrogen application and increasing selenium content of grains. A pot experiment was carried out under greenhouse conditions with Se1 (0.74 mg·kg-1) or Se2 (2.60 mg·kg-1) levels of selenium, and each Se treatment was supplied with N1 (100 mg·kg-1) or N2 (200 mg·kg-1) levels of nitrogen, respectively. Selenium concentrations and biomass amounts of different parts of wheat were determined at jointing and maturity stage. The results showed that grain yield increased with increasing nitrogen levels by 13.2% and 24.0% in Se1 and Se2 treatment, respectively. Regardless of N rate, Se concentration of wheat increased with raising Se amended rate (P<0.01). Increasing nitrogen application could promote Se uptake of root and thus increase the selenium concentration of wheat grains and leaves, which was greater in Se1 treatment than in Se2 treatments. Se concentrations in wheat grain increased by 22.6% and 12.1% with the increasing N application rate in low and high Se treatment, respectively. The distribution ratios of Se in each organ ranked the same as BCFs, following the order of leaf > grain > glume > root. Increasing N fertilization increased the distribution ratio of Se in grains by 11.1% and 25.9% in low and high selenate treatments, respectively. High nitrogen fertilization could promote uptake and translocation of Se in wheat under low Se conditions, and improve Se use efficiency as well in the agricultural production.

Dietary administration of saponin stimulates growth of the swimming crab Portunus trituberculatus and enhances its resistance against Vibrio alginolyticus infection.

The immunostimulatory role of dietary saponins on swimming crabs was investigated under field conditions. Portunus trituberculatus were fed diets enriched with Quillaja saponin (QS) at 150, 300 and 450 mg kg-1. They had an enhanced growth rate and increased resistance against Vibrio alginolyticus compared to crabs not fed with QS. Significant effects were observed on the average body weight, percentage weight gain and specific growth rate (p < 0.05). Total hemocyte and hyaline cell counts of P. trituberculatus fed with 300 and 450 mg kg-1 saponin in their diets significantly increased (p < 0.05) compared to the control. Phenoloxidase, superoxide dismutase, catalase and glutathione peroxidase activities significantly increased in response to the incorporation of QS in the diet. However, the respiratory burst activity did not increase significantly. The phagocytic activity was significantly enhanced at 300 and 450 mg kg-1 of saponin. QS diets can enhance growth of P. trituberculatus and its immune resistance against V. alginolyticus. Dietary administration of saponin may help to control diseases and improve production in the crab aquaculture industry.

Effectiveness of a hydroxynaphthoquinone fraction from Arnebia euchroma in rats with experimental colitis.

AIM: To evaluate the potential effectiveness of hydroxynaphthoquinone mixture (HM) in rats with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: Colitis was induced by intracolonic administration of TNBS (80 mg/kg, dissolved in 50% ethanol). Rats were treated daily for 7 d with HM (2.5, 5, 10 mg/kg) and mesalazine 100 mg/kg 24 h after TNBS instillation. Disease progression was monitored daily by observation of clinical signs and body weight change. At the end of the experiment, macroscopic and histopathologic lesions of rats were scored, and myeloperoxidase (MPO) activity was determined. We also determined inflammatory cytokine tumor necrosis factor (TNF)-α level by ELISA, Western blotting and immunochemistry to explore the potential mechanisms of HM. RESULTS: After intracolonic instillation of TNBS, animals developed colitis associated with soft stool, diarrhea and marked colonic destruction. Administration of HM significantly attenuated clinical and histopathologic severity of TNBS-induced colitis in a dose-dependent manner. It abrogated body weight loss, diarrhea and inflammation, decreased macroscopic damage score, and improved histological signs, with a significant reduction of inflammatory infiltration, ulcer size and the severity of goblet cell depletion (all P < 0.05 vs TNBS alone group). HM could reduce MPO activity. In addition, it also decreased serum TNF-α level and down-regulated TNF-α expression in colonic tissue. This reduction was statistically significant when the dose of HM was 10 mg/kg (P < 0.05 vs TNBS alone group), and the effect was comparable to that of mesalazine and showed no apparent adverse effect. The underlying mechanism may be associated with TNF-α inhibition. CONCLUSION: These findings suggest that HM possesses favourable therapeutic action in TNBS-induced colitis, which provides direct pharmacological evidence for its clinical application.

Abscisic acid enhances resistance to Alternaria solani in tomato seedlings.

The plant hormone abscisic acid (ABA) is an important regulator in many aspects of plant growth and development, as well as stress resistance. Here, we investigated the effects of exogenous ABA application on the interaction between tomato (Solanum lycopersicon L.) and Alternaria solani (early blight). Foliar spraying of 7.58 µM ABA was effective in reducing disease severity in tomato plants. Previously, increased activities of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD) were observed in exogenous ABA-treated tomato leaves. Moreover, these enzyme activities were maintained at higher levels in ABA-pretreated and A. solani challenged tomato plants. Tomato defense genes, such as PR1, ß-1, 3-glucanase (GLU), PPO, POD, and superoxide dismutase (SOD), were rapidly and significantly up-regulated by exogenous ABA treatment. Furthermore, a subsequent challenge of ABA-pretreated plants with the pathogen A. solani resulted in higher expression of defense genes, compared to water-treated or A. solani inoculated plants. Therefore, our results suggest that exogenous ABA could enhance disease resistance against A. solani infection in tomato through the activation of defense genes and via the enhancement of defense-related enzymatic activities.

Infusion of glucose and lipids at physiological rates causes acute endoplasmic reticulum stress in rat liver.

Endoplasmic reticulum (ER) stress has recently been implicated as a cause for obesity-related insulin resistance; however, what causes ER stress in obesity has remained uncertain. Here, we have tested the hypothesis that macronutrients can cause acute (ER) stress in rat liver. Examined were the effects of intravenously infused glucose and/or lipids on proximal ER stress sensor activation (PERK, eIF2-α, ATF4, Xbox protein 1 (XBP1s)), unfolded protein response (UPR) proteins (GRP78, calnexin, calreticulin, protein disulphide isomerase (PDI), stress kinases (JNK, p38 MAPK) and insulin signaling (insulin/receptor substrate (IRS) 1/2 associated phosphoinositol-3-kinase (PI3K)) in rat liver. Glucose and/or lipid infusions, ranging from 23.8 to 69.5 kJ/4 h (equivalent to between ~17% and ~50% of normal daily energy intake), activated the proximal ER stress sensor PERK and ATF6 increased the protein abundance of calnexin, calreticulin and PDI and increased two GRP78 isoforms. Glucose and glucose plus lipid infusions induced comparable degrees of ER stress, but only infusions containing lipid activated stress kinases (JNK and p38 MAPK) and inhibited insulin signaling (PI3K). In summary, physiologic amounts of both glucose and lipids acutely increased ER stress in livers 12-h fasted rats and dependent on the presence of fat, caused insulin resistance. We conclude that this type of acute ER stress is likely to occur during normal daily nutrient intake.