The impacts of different nutrient additions (N + P, N + P + C, 4N + P, 4N + P + C, N + 2P) on the growth of algae and bacteria were studied in a microcosm experiment. Since alkaline phosphatase activity (APA) provides an indication of phosphorus deficiency, the higher value for algal APA in the treatments with excess nitrogen and for bacterial APA in the treatments with excess carbon suggested that, algal and bacterial phosphorus-limited status were induced by abundant nitrogen and carbon input, respectively. Bacterial phosphorus-limited status was weakened due to higher bacterial competition for phosphorus, compared to algae. In comparison with the bacterial and specific bacterial APA, higher values of algal and specific algal APA were found, which showed a gradual increase that coincided with the increase of chlorophyll a concentration. This fact indicated not only a stronger phosphorus demand by algae than by bacteria, but also a complementary relationship for phosphorus demand between algae and bacteria. However, this commensalism could be interfered by glucose input resulting in the decline of chlorophyll a concentration. Furthermore, the correlation between bacterial numbers and chlorophyll a concentration was positive in treatments without carbon and blurry in treatments with carbon. These observations validate a hypothesis that carbon addition can stimulate bacterial growth justifying bacterial nutrient demand, which decreases the availability of nutrients to algae and affects nutrient relationship between algae and bacteria. However, this interference would terminate after algal and bacterial adaption to carbon input.

Therefore, methodology for synthesizing dienals has attracted the attention of synthetic organic chemists. The methods reported in the literature use LiCH=CH-CH=CHOEt[2] or CH3COCH =CHSCMe3 [3] with aldehyde, but both of these suffer from difficulty in obtaining the reagents or from the need for multiple-step reactions to afford the desired dienal. Alternatively, a Wittig reagent, Ph3P=CHCH=CHCH0, has been used [4]. Its application to the synthesis of leukotriene has appeared in the literature [5]. A roundabout procedure to achieve formylenylolefination has been used, for example, in the synthesis of Wallemia A [61.Wallemia A In extension of our previously reported formylolefination via an arsonium salt [7] we would like to report here a facile formylenylolefination via the arsonium salt, formylallyltriphenylarsonium bromide (2), and its application in the syntheses of navenone A [8] and Otanthus maritima amide [9].

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.