The smell and odorous components of dried shiitake mushroom, Lentinula edodes V: changes in lenthionine and lentinic acid contents during the drying process

This study on dried shiitake mushroom [Lentinula edodes (Berk.) Pegler] focuses on the behavior of the aromatic lenthionine compound and its precursor, lentinic acid, during the drying process. Only a small amount of lenthionine was present after the drying process, regardless of the drying temperature or time; however, the amount increased during the rehydration process using pH 8.0 buffer. The lenthionine content after incubation in the buffer was correlated with the lentinic acid content in the dried shiitake mushroom. The lentinic acid content increased signifi cantly during the drying process at 40°C up to 4 h. The results show that the characteristic smell of dried shiitake mushroom was weak after drying, and that rehydration in a mild alkaline solution was necessary to increase the smell. The lentinic acid content of dried shiitake could serve as an indicator of the smell produced by rehydration and would be useful in screening to select odor-rich strains. Moderate heating likely caused the increase in lentinic acid content, which might be related to a reaction to heat.     

The smell and odorous components of dried shiitake mushroom, Lentinula edodes VI: increase in odorous compounds of dried shiitake mushroom cultivated on bed logs

Odor is one of the most important characteristics affecting consumer preference for dried shiitake mushrooms [Lentinula edodes (Berk.) Pegler]. In our previous studies, we found that the odor content of commercial dried products was too weak for most people, and that the odorous compound content could be increased by adding amino acids to sawdust media. Currently, however, bed-log cultivation is used to produce fruiting bodies for dried products. The purpose of this study was to fi nd a method to increase the content of odorous compounds in dried products cultivated on bed logs. Pressure injection of amino acids from the side of the bed log was the most effi cient method, but it had some problems. Hence, a simpler and less troublesome method was developed, i.e., injecting amino acid solution from small bottles set in deep holes bored in the sides of the bed logs. In fruiting bodies cultivated on bed logs injected with amino acid solution by the improved method, the mean contents of lentinic acid, a precursor of the odorous compound lenthionine, approximately doubled compared to that in the untreated logs, although the infi ltration area of the solution injected by the improved method was smaller than that by the former method.     

祁门红茶的香气特征

通过对祁红当家品种——槠叶群体种及其适制绿茶的亲缘种——安徽7号(对照)在加工红茶的过程中香气形成的动态分析和比较研究表明,在祁红检出的110多种香气成分中,己醛,1-戊烯-3-醇、反-2-己烯醛、顺-3-己烯醇、芳樟醇氧化物Ⅱ、芳樟醇、香叶醇、橙花叔醇等含量较高。在相同的祁红加工过程中,槠叶群体的香气物质形成总量高于对照,且形成高峰超前,其中香叶醇含量在揉捻阶段剧增;与安徽7号相比,香叶醇含量高出30倍以上,而其他香气成分含量则无明显差异。实验还发现,两品种茶叶在加工过程中,儿茶素的减少与茶叶香气总量及其中的萜烯醇类的增长均具有很好的对应关系,槠叶群体中有关香气配糖体的含量高于安徽7号,文中对此作了讨论。     

Studies on wetting phenomena on plant leaf surfaces. 3: A retention model for droplets on solid surfaces

To investigate the factors governing retention of pesticidal spray solutions on plant surfaces, a new retention model for droplets on solid surfaces has been introduced as where ΔΘ = Θ_a – Θ_r. The minimum sliding volumes (MiSV) of surfactant aqueous solutions (2 g litre^?-1; surface tensions; 28·5 – 72·5 mN m^?-1) on smooth surfaces of paraffin wax and polymer sheets were measured and the validity of the above retention equation was verified on combinations of these solutions and surfaces. A concept of the specific adhesional force (F_a) of a droplet was defined as which was the maximum adhesional force on a unit length of the width of the contact circle of a droplet, and F_a values of the solutions on the surfaces were compared. The predominant factors for droplet retention are discussed on the basis of this model.     

中国茶树的起源与分布——根据茶叶香气组分中萜烯指数化学分类所作的推论(英文)

茶挥发性成分中的萜烯醇类具有生物合成的遗传特性。根据萜烯指数(即:芳樟醇及其氧化物/(芳樟醇及其氧化物十香叶醇)比值,TI〕所作的化学分类表明,云南省茶的 TI 值接近于1.0,而分布于其他产茶省区的茶树 TI 值均低于上述值,并伴随有由西南向东和东南逐渐下降的趋势。由云南引入的日本山茶,具有与云南相近的 TI 值,而日本当地茶树品种的 TI 值与中国浙江相近似,因而推测中国茶树的原产地为云南,然后沿长江和沿海逐渐向东和南方传播。     

Mating disruption controls the cherry tree borer, <Emphasis Type="Italic">Synanthedon hector</Emphasis> (Butler) (Lepidoptera: Sesiidae), in a steep orchard of cherry trees

Mating disruption of the cherry tree borer, Synanthedon hector (Butler), with synthetic sex attractant was conducted for 6 years to test the efficiency of the method to control the borer population on the slopes in the Cherry Tree Forest of Tama Forest Science Garden, Hachioji, Tokyo. No male adult moth has been captured in traps baited with the synthetic attractant since the commencement of the control. The incidence of attack decreased to a low level in the third year and has remained low thereafter, indicating the effectiveness of mating disruption in controlling the borer population.     

AKD-2023: A novel miticide. Biological activity and mode of action

AKD-2023, 3-dodecyl-1,4-dihydro-1,4-dioxo-2-naphthyl acetate (proposed common name acequinocyl) is a novel miticide now under commercial development. It has outstanding miticidal activity against economically important spider mites with the new mode of action of inhibition of mitochondrial electron transfer at complex III.     

光肩星天牛忌避剂的初步研究(英文)

对臭椿忌避性的研究表明,光肩星天牛成虫在所采用的两个规格的 Ｙ 字管中不表现“趋”或“避”的选择,爬行方向是盲目的;天牛成、幼虫在仅有臭椿材料条件下,可以正常取食,幼虫一个月之内无明显异常．色谱分析的结果是,臭椿与合作杨枝叶中,溶于有机溶剂物质部分的碳氢化合物大多在碳２５ 以内,两者的色谱有着明显区别．对七种混合物的忌避性初步研究显示, Ｄ, Ｆ, Ｇ 对天牛具有较强的忌避性, Ｄ 和 Ｇ 是值得进一步做小面积林间应用研究的忌避剂