PHENOLIC COMPOUNDS FROM THE BERRIES OF MOUNTAIN ASH, Sorbus aucuparia

The polyphenolic extract from berries of Mountain Ash was separated into fractions in order to determine whether phenolic compounds are responsible for the bitter taste of the berries. The 18 phenols isolated included hydroxycinnamic acids, anthocyanins, leucoanthocyanins and flavanols, none of which had a strong bitter taste.     

FORMATION OF TOXIC METHYLHYDRAZINE DURING COOKING OF FALSE MORELS, GYROMITRA ESCULENTA

Methylhydrazine, the main metabolite of N-methyl-N-formylhydra-zones, was detected in the cooking steam of the mushrooms False morels, Gyromitra esculenta. About 25% of the original amount of acetaldehyde-N-methyl-N-formylhydrazone was decomposed during cooking process to methylhydrazine and residues of N-methyl-N-formylhydrazine was detected as well.     

Tuning of a multivariable discrete time PI controller for unknown systems

Tuning of a multivariable discrete time PI controller, which uses interactions of the plant is discussed. Interactions are detected by observing the plant response to step inputs. The plant is assumed to be unknown, linear, time invariant and stable. The tuning method presented is an extension of the corresponding continuous time method (Davison 1976, Penttinen and Koivo 1980)     

Volatile Fatty Acids in Some Brands of Whisky, Cognac and Rum

SUMMARY— Gas chromatography was applied to eight different types of whisky, two of cognac, one of brandy, and four of rum to determine the relative proportions of volatile fatty acids; with the lower molecular acids as free acids, but upwards from caprylic acid as methyl esters. Acetic acid and the total amount of volatile acids were measured quantitatively. Rum contained the largest amount of volatile acids, 600 mg/L, while one of the brands of Scotch whisky contained the least, 90 mg/L. Acetic acid represented 40–95% of the total amount of volatile acids in the whisky; for cognac and brandy, the value was .50–75%, and for rum 75–90%. The relative amounts have been reported for 21 acids, with acetic acid excluded. Capric, caprylic and lauric acid were the main components in whisky, cognac and brandy. Of the beverages analyzed, rum contained the largest quantity of lower fatty acids, particularly propionic and butyric acid; the main component of Jamaican rum was propionic acid. The main components of the group of long-chain fatty acids were myristic, palmitic and palmitoleic acids. Scotch whisky contained equal amounts of palmitic and palmitoleic acid; palmitoleic acid regularly appeared in smaller amounts in the other beverages     

PLANT HORMONES IN FUNGI AND BACTERIA FROM MALTING BARLEY

40 Fungi and 16 strains of bacteria, isolated from the grains of three cultivars of matting-grade barley (Kymppi, Pokko and Kustaa, of 1990 harvest), were screened for the production of the plant hormones gibberellic acid (GA₃, abscisic acid (ABA) and indole-3-acetic acid (IAA). Four fungal strains were found capable of GA₃ production and four of ABA production. IAA production was common among both fungi (58% of strains active) and bacteria (88% of strains active). To get an estimate of the physiological significance of the presence of plant hormone producing microbes, the plant hormone production per microbial unit in the liquid growth media of the cultured organisms was weighed against the microbial counts and the endogenous hormone concentrations of barley grains. It was concluded that bacterial IAA production could be of significance in imbibed grains. This presupposes, however, that the conditions be ideal for the propagation of the active species and also, for the production of IAA by those same species and lastly, that similar production occurs in vivo as well as in vitro. Microbial GA3 and ABA production, on the other hand, were estimated to occur in negligent amounts.     

优化磁性粒子为基础的系统的DNA纯化方案的重要性

从复杂生物基质中快速、高效地分离核酸是在获取各种实验的最佳起始原料的重要一步。磁性粒子为基础的操作流程提供了一个快速简单的解决方案,它特别适合用于自动化,在获得纯净和完整的DNA或RNA时以最少的动手时间获得良好的重现性结果。因此,必须优化基于磁珠的纯化流程来达到最高质量与数量的核酸提取。本文介绍了一个自动化、高速、以磁性粒子为基础的纯化系统来实现理想的DNA纯化方案,并考察了不同搅拌速度组合,以及在洗脱步骤的加热效应对DNA纯化数量和质量的影响。     

AMELIORATION OF TOXIC EFFECTS OF ETHYLIDENE GYROMITRIN (FALSE MOREL POISON) WITH PYRIDOXINE CHLORIDE

Repeated (five) doses of pyridoxine chloride (vitamin B₆, 10 mg) reduced botht he neurological symptoms caused by ethylidene gyromitrin, the main poisonous compound of the mushroom false morel (Gyromitra esculenta pers. Fr.), and the overall mortality due to ethylidene gyromitrin poisoning in mice treated orally with this poison (400 mg/kg). In contrast, little or no effect was found when the mice were treated with γ-aminobutyric acid (1 mg) or vitamin C (10 mg) after treatment with poison. The significance of these findings is discussed in perspective to possible treatments of human poisonings caused by false morel.