Production of DON-related trichothecenes byFusarium graminearum Schw from Krasnodarski krai of the USSR

34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals.     

Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex

The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S nuclear ribosomal DNA sequence and the intervening 5.8S region were sequenced from three individuals in each of eight taxa of the Mimulus guttatus species complex. Three discrete variants, or "types," of ITS sequences were found, among which 30%-40% of sites differed, compared with 1%-2% within types. Dot plots indicate that these types were not related by conspicuous rearrangements or inversions. More than one ITS type was often found in the same taxon, and two of three ITS types span species boundaries, indicating their presence prior to speciation. These ITS sequences showed essentially no positional homology with the nearest sequenced relative, tomato. In contrast, the 5.8S region was relatively unvaried, with 8 of 162 sites varied in the sample among all eight taxa. The phylogeny inferred by the most common ITS sequence type, rooted by the two other ITS types, agreed with isozymes in showing the distinctness of M. nudatus, M. laciniatus, and M. tilingii from the other five taxa.      

Isolation and properties of a particulate fraction for the desaturation of palmitic acid from Alcaligenes faecalis.

A particulate fraction obtained from Alcaligenes faecalis could desaturate palmitic acid to palmitoleic acid. NADPH, ATP, CoA, Fe2+ and Mg2+ were essential cofactors for the reaction. The desaturation showed an absolute requirement for O2. Metal ions like Mn2+, Mo6+ and Cu2+ did not affect the desaturation, while Zn2+ was inhibitory. Sulfhydryl agents such as cysteine, glutathione and beta-mercaptoethanol had no effect, but SH-blocking agents like HgCl2 and p-hydroxymercuribenzoate inhibited the reaction. Azide and cyanide strongly inhibited the reaction while CO had no effect. The presence of a b-type cytochrome in the enzyme preparation was confirmed by the spectral studies on the reaction of enzyme with NADPH. Involvement of b-type cytochrome in the desaturation reaction was demonstrated by the reoxidation of b-type cytochrome initially reduced with NADPH, by the addition of palmitic acid and other cofactors. The pH optimum for the enzyme activity was 7.4. The optimum temperature for enzyme activity was 25 degrees C and maximum activity was obtained at the end of 45 min.     

中国小菇属十个新记录种

报道了小菇科小菇属真菌10个中国新记录种,香菌组：橙盖小菇Mycena aurantiidisca、黄白小菇Mycena flavoalba、粉黄小菇Mycena floridula;棘刺组：异刺小菇Mycena heteracantha;纤柄组：碱味小菇Mycena amygdalina;脆足组：粉被小菇Mycena zephirus;冬生组：绣线菊小菇Mycena speirea、冬生小菇Mycena hiemalis;小菇组：绒柄小菇Mycena flos-nivium,分别来自吉林等11个省份、自治区。提供了每个物种的形态描述和线条图,以及与相近种的讨论。共计90条自测及下载ITS序列,在采用贝叶斯法和最大似然法构建的小菇属系统发育树中,新记录种均得到分子数据支持。凭证标本存放于吉林农业大学菌物标本馆（HMJAU）。     

Plant regeneration through direct and indirect organogenesis,phyto-molecular profiles,antioxidant properties and swertiamarin production in elicitated cell suspension cultures of Swertia minor (Griseb.) Knobl

Plant Cell, Tissue and Organ Culture (PCTOC) - The present study reports an optimized protocol for high frequency in vitro plant propagation through direct and indirect organogenesis, phytochemical...     

Highly efficient in vitro proliferation and genetic stability analysis of micropropagated Ceropegiaevansii by RAPD and ISSR markers: A critically endangered plant of Western Ghats

Ceropegiaevansii McCann (family: Asclepiadaceae), a critically endangered plant of Western Ghats has acquired significant importance due to its medicinal implications, edible tubers, and ornamental flowers. This study deals with the optimization of axillary bud proliferation using nodal explants followed by genetic stability analysis of regenerants. Maximum number of shoots (11.6 ± 1.1) was observed on the Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurine (4.0 mg/l) and indole-3-acetic acid (0.3 mg/l) with 85% shoot multiplication frequency. In vitro-grown shoots were rooted best in 1/2 MS medium supplemented with indole-3-butyric acid (1.0 mg/l) with an average of 10.3 ± 0.9 roots per shoot and 92% rooting frequency. Plantlets were acclimatized best (90%) in a mixture of sterile soil, sand, and coco peat (1:2:1). Micropropagated plants were subjected to random amplified polymorphic DNA and inter simple sequence repeat markers analyses. Collectively, 759 bands were generated which were monomorphic and similar to the mother plant. Findings of this study are the first report on micropropagation and assessment of genetic stability of micropropagated plantlets in C. evansii which suggests that axillary shoot proliferation can safely be used as an effective tool for propagation and conservation of C. evansii.     

川芎嗪对Aβ25-35诱导体外大鼠海马神经元细胞凋亡的影响

本文通过Aβ25-35诱导体外原代培养的SD乳大鼠海马神经元,建立Aβ毒性损伤细胞模型,结合AnnexinV-FITC/PI荧光双染法流式细胞术、MTT比色法、实时荧光定量PCR及Western blot方法检测川芎嗪(tetrameth-ylpyrazine,TMP)对原代培养的海马神经元细胞活性、早期凋亡率和Bax、Bcl-2基因表达的影响。结果显示川芎嗪高、中剂量可明显增强细胞活性,增加神经元细胞的存活率(P<0.01),可显著抑制海马神经元细胞早期凋亡(P<0.01),抑制凋亡蛋白Bax的表达(P<0.01),增强抗凋亡蛋白bcl-2的表达(P<0.01)。川芎嗪可通过调节Bax/Bcl-2平衡抵抗Aβ25-35诱导的海马神经元凋亡,降低Aβ的神经元毒性,对海马神经元损伤有明显的保护作用。     

Modelling expected trout ranges under current and future water temperature regimes in the Eastern Cape,South Africa

Different values have resulted in conflicts between anglers and conservation lobbies in the management of trout in South Africa. Key to the conflict is the demarcation of boundaries to areas in which brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss currently occur, or are likely to establish following stocking for angling. To provide a longer-term perspective on these areas, we developed models to link salmonid biological thermal thresholds to elevation. These, when applied spatially using a digital elevation model with a probability of occurrence model, provided the basis for estimating potentially available thermal habitat for these two cold water species. Here, we acknowledge that other variables (stocking history; river connectivity) also play a role in understanding trout distributions. Using a simple scenario of an increase in mean daily water temperatures of 2 °C, we demonstrated that both brown and rainbow trout are likely to exhibit considerable range reductions in the future. Because it is possible that these range restrictions will result in an increasing desire to introduce trout into areas above their current distribution limits for the maintenance of angling opportunities, conservation managers should prioritise these areas, with management interventions seeking to understand what will help to limit introductions.