阿拉伯胶和香精油对香蕉及番木瓜贮藏过程中炭疽病及品质的控制效果

严格控制由刺盘孢属(Colletotrichum spp.)真菌引起的炭疽病对减少热带水果工业的经济损失十分重要。本文主要研究了阿拉伯胶(GA)(10%)、柠檬香草精油(LG)(0.05%)、肉桂精油(CM)(0.4%)及其复合组分在试验条件下对离体与活体香蕉和番木瓜炭疽病菌的抑制活性。结果表明,0.05%的LG和0.4%的CM对于引起香蕉和番木瓜炭疽病的两种病原菌Colletotrichum musae和Colletotrichum gloeosporioides分别具有抑制活性;单独GA处理并未表现出抑菌活性,但将0.05%LG、0.4%CM与10%GA混合处理则具有较大的抑菌活性;在各处理中,以PDA培养基中加入10%GA及0.4%CM的处理对C.musae和C.gloeosporioides这两种病原菌抑制活性最显著,对于两种病原菌菌丝生长抑制率分别为73.4%和70.0%,对孢子萌发抑制率分别为88%和85%。活体试验结果也表明,10%GA结合0.4%的CM处理具有最佳的作用效果,对C.musae和C.gloeosporioides的抑制方面表现出较强的增效作用,对人工接种的香蕉和番木瓜炭疽病导致的腐烂抑制率分别为80%和71%。品质评价的试验结果也表明,10%GA结合0.4%CM的涂膜处理具有良好效果,果实失重率、硬度、可溶性固形物和可滴定酸含量的变化均表明该处理可显著推迟果实的成熟。上述结果表明,10%阿拉伯胶结合0.4%肉桂精油处理可以作为控制诸如香蕉和番木瓜等常见热带水果采后炭疽病的生物杀菌剂。     

The growth factor progranulin binds to TNF receptors and is therapeutic against inflammatory arthritis in mice

The growth factor progranulin (PGRN) has been implicated in embryonic development, tissue repair, tumorigenesis, and inflammation, but its receptors remain unidentified. We report that PGRN bound directly to tumor necrosis factor receptors (TNFRs) and disturbed the TNFα-TNFR interaction. PGRN-deficient mice were susceptible to collagen-induced arthritis, and administration of PGRN reversed inflammatory arthritis. Atsttrin, an engineered protein composed of three PGRN fragments, exhibited selective TNFR binding. PGRN and Atsttrin prevented inflammation in multiple arthritis mouse models and inhibited TNFα-activated intracellular signaling. Collectively, these findings demonstrate that PGRN is a ligand of TNFR, an antagonist of TNFα signaling, and plays a critical role in the pathogenesis of inflammatory arthritis in mice. They also suggest new potential therapeutic interventions for various TNFα-mediated pathologies and conditions, including rheumatoid arthritis.     

Carbon,nitrogen, and phosphorus stoichiometry mediate sensitivity of carbon stabilization mechanisms along with surface layers of a Mollisol after long-term fertilization in Northeast China

Journal of Soils and Sediments - Soil organic carbon (SOC) is an important parameter determining soil fertility and sustaining soil health. How C, N, and P contents and their stoichiometric ratios...     

Photosystem II and cellular membrane stability evaluation in hexaploid wheat seedlings under salt stress conditions

Salinity limits crop production in large areas of the world. The application of in vitro Photosystem II (PS‐II) activity measurements to screen hexaploid wheat (Triticum aestivum, L.) genotypes for NaCl tolerance has been investigated by comparing their responses under stress and control (no added NaCl) conditions. One of the four cultivars used in the study was ‘Kharchia’ known for its high salt tolerance. Wheat seedlings were grown hydroponically in environmental chambers and treated with a range of NaCl concentrations (0.034 M, 0.17 M, 0.68 M, or 3.42 M) over a 1, 3, and 5‐day period. The salt treatments were started in the appropriate time so that they were all ten‐day‐old during harvest. Cellular membrane stability (CMS) as measured by a conductivity method and PS‐II activity values were affected adversely by NaCl concentration and duration of treatment. Both methods clearly distinguish between salt‐sensitive and salt‐tolerant genotypes. Statistical analysis showed that PS‐II activity and CMS measurements are well correlated (r=0.7589) suggesting that PS‐II activity would be used as an additional screening method besides CMS to evaluate salt tolerance of wheat.     

Biocontrol efficiency of Fusarium wilt diseases by a root-colonizing fungus Penicillium sp.

Soil-inhabiting fungal pathogen Fusarium oxysporum often causes severe yield losses in many crops. We investigated the effect of a plant growth-promoting fungus, Penicillium sp. EU0013 on Fusarium wilt disease. In dual culture experiments, EU0013 inhibited the growth of Fusarium wilt pathogens by producing an inhibition zone. In experiments using sterile potting medium under controlled conditions, EU0013 significantly reduced the severity of Fusarium wilt on tomato (Solanum lycopersicum L.) and cabbage (Brassica oleracea L. var. capitata). In non-sterile soil, benomyl-resistant mutants of EU0013 were selected by exposing the conidial solution of EU0013 to ultraviolet light. The selected mutant EU0013_90S isolate did not show any distinct differences from EU0013 in colony characteristics, growth rate or antifungal activity against Fusarium wilt pathogens in dual culture. The effect of EU0013_90S on tomato wilt was studied under greenhouse conditions using non-sterile soil. Two-weeks old tomato seedlings were dipped in four different concentrations of EU0013_90S conidial suspension (1?×?10³, 1?×?10⁴, 1?×?10⁵, and 1?×?10⁶ conidia mL^–1). Seedlings were then planted in soil inoculated with either F. oxysporum f. sp. lycopersici race 1 CU1 or race 2 JCM 12575 (1?×?10⁶ bud-cells g^–1). We found the greatest disease suppression occurred when seedlings were dipped in the highest concentration of EU0013_90S conidia. This same inoculum concentration of EU0013_90S also resulted in the highest disease reduction in soil infested with JCM 12575. Higher root colonization with EU0013_90S showed a significant reduction in Fusarium wilt disease, suggesting that colonization by Penicillium sp. EU0013_90S is important for efficient biocontrol of these diseases.     

A Simple PCR Procedure to Detect White Spot Syndrome Virus (WSSV) of Shrimp, <Emphasis Type="Italic">Penaeus monodon</Emphasis> (Fabricious)

A non-stop, single tube and semi-nested polymerase chain reaction (PCR) technique with simple procedure was developed for simultaneous detection and grading the level of white spot syndrome infection in penaeid shrimp, Penaeus monodon. In this PCR procedure, three sense primers and one antisense primer with uniform annealing temperature of 55 °C were used. These primers amplify three PCR products (500, 300 and 200 base pairs [bp]) depending upon the severity of infection. Quantities of WSSV-DNA at 10 pg and greater gave three PCR products of 500, 300, 200 bp. A moderate concentration of WSSV-DNA, around 100 fg, gave two products of 300 and 200 bp and a low concentration of 1 fg or more gave only one PCR product of 200 bp. This PCR technique was assessed for early detection of WSSV in shrimp. In time-course infectivity experiments conducted on shrimp with WSSV, one PCR product (200 bp) was seen in hemolymph, tail tissue and gill at 3 h post infection (p.i.); two PCR products (300 and 200 bp) were seen in tail tissue, hemolymph, heart tissue and gill at 18 h p.i. At 30 h p.i., three PCR products (500, 300, 200 bp) were seen in all the organs tested. The samples collected from control animals showed negative for WSSV.     

Hexane Extract of Raphanus sativus L. Roots Inhibits Cell Proliferation and Induces Apoptosis in Human Cancer Cells by Modulating Genes Related to Apoptotic Pathway

Raphanus sativus, a common cruciferous vegetable has been attributed to possess a number of pharmacological and therapeutic properties. It has been used in indigenous system of medicine for the treatment of various human ailments in India. This present study evaluated the chemopreventive efficacy of different parts of R. sativus such as root, stem and leaves, extracted with solvents of varying polarity and investigated the molecular mechanism leading to growth arrest and apoptotic cell death in human cancer cell lines. Of the different parts, significant growth inhibitory effect was observed with hexane extract of R. sativus root. Analysis of hexane extract by GC-MS revealed the presence of several isothiocyanates (ITCs) such as 4-(methylthio)-3-butenyl isothiocyanate (MTBITC), 4-(methylthio)-3-butyl isothiocyanate (erucin), 4-methylpentyl isothiocyanate, 4-pentenyl isothiocyanate and sulforaphene. R. sativus root extract induced cell death both in p53 proficient and p53 deficient cell lines through induction of apoptotic signaling pathway regardless of the p53 status of cells. The molecular mechanisms underlying R. sativus-induced apoptosis may involve interactions among Bcl₂ family genes, as evidenced by up-regulation of pro-apoptotic genes and down-regulation of anti-apoptotic genes along with activation of Caspase-3. Our findings present the first evidence that hexane extract of R. sativus root exerts potential chemopreventive efficacy and induces apoptosis in cancer cell lines through modulation of genes involved in apoptotic signaling pathway.     

Effect of hot acetic acid solutions on postharvest decay caused by Penicillium expansum on Red Delicious apples

The objective of this research was improvement of apple hot water treatment efficiency by using acetic acid. The apples (cultivar Red Delicious) were treated using hot acetic acid solutions (1, 2 and 3%) at 50 °C for 1, 2 and 3 min. The results of in vitro study showed that treatment with acetic acid at 50 °C can significantly reduce the growth of Penicillium expansum spores. The treatment of apples with 50 °C acetic acid solutions, in particular 2% acetic acid solution for 3 min or 3% acetic acid solution for 2 min, had significant impacts in reducing the extent of decay of the fruit during the short time storage experiment, while this effect was not significant in the long-time storage.     

Factors affecting the occurrence of smooth‐coated otter in aquatic systems of the Upper Gangetic Plains,India

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Evaluation of the effects induced by dietary diphenyl diselenide on common carp Cyprinus carpio

Several diets employed in aquaculture are enriched with selenium (Se), as it is a fundamental element to aquatic vertebrates. Diphenyl diselenide [(PhSe)₂], which is a synthetic organoselenium compound, has been considered a potential antioxidant agent in different experimental models. Thus, the aim of this study was to evaluate the effects of dietary diphenyl diselenide at concentrations of 1.5, 3.0, and 5.0 mg/kg for 60 days and to determine its optimal supplemental level for carp, Cyprinus carpio. Neither growth retardation nor hepatoxicity was induced by the inclusion of diphenyl diselenide at concentrations ranging from 1.5 to 5.0 mg/kg. In addition, the inclusion of 3.0 mg/kg of diphenyl diselenide stimulated the weight and length of the carp. The supplementation with 1.5 and 3.0 mg/kg of diphenyl diselenide did not produce oxidative damage in the tissues, verified by peroxidation lipid and protein carbonyl assays. However, at 5.0 mg/kg, it caused an increase of the lipid peroxidation in the liver, brain, and muscle, and inhibited the cerebral acetylcholinesterase activity. An increase of the hepatic superoxide dismutase activity and non-protein thiols content in all tissues and ascorbic acid in the liver, gills, and brain was verified in carp fed with the diet containing 3.0 mg/kg of diphenyl diselenide. This diet had advantageous effects for the fish used in experiments. Therefore, this compound could be considered a beneficial dietary supplement for carp nutrition.