Chemical constituents isolated from turnera subulata Sm. and electrochemical characterization of phaeophytin b

Turnera subulata Sm., known as "Chanana" or "flor-do-Guarujá" in Brazilian folklore, is a plant species belonging to the subfamily Turneroideae of family Passifloraceae, which is used for various medicinal purposes in Brazil. The phytochemical study conducted here led to the isolation and identification of ten compounds present in T. subulata: two mixtures of steroids, sitosterol and stigmasterol (nonglycosylated and glycosylated); a mixture of flavonoids, 5,7,4′-trihidroxiflavona-8-C-α-glucopyranoside and 5,7,3′,4′-tetrahidroxiflavona-8-C-α-glucopyranosidel; and four phaeophytins, phaeophytin purpurin-18-phytyl ester, a rare natural product, phaeophytin a , 13²-hydroxy-(13²-S)-phaeophytin a , and phaeophytin b Phaeophytin b exhibited electrochemical activity similar to that of phthalocyanines.

Caldensinic acid, a benzoic acid derivative and others compounds from Piper carniconnectivum

A benzoic acid derivative - caldensinic acid; E-phytyl hexadecanoate; β-sitosterol and stigmasterol mixture and phaeophytin a were isolated from the aerial parts of Piper carniconnectivum. The structures of these compounds were established unambiguously by IR, MS, 1D and 2D NMR analysis.

Phaeophytins from Thyrsacanthus ramosissimus Moric. with inhibitory activity on human dna topoisomerase II-α

Our study reports the extraction and isolation of a new phaeophytin derivative 15¹-hydroxy-(15¹-S)-porphyrinolactone, designated anamariaine (1) herein, isolated from the chloroform fraction of aerial parts of Thyrsacanthus ramosissimus Moric. along with the known 15¹-ethoxy-(15¹-S)-porphyrinolactone (2). These compounds were identified by usual spectroscopic methods. Both compounds were subjected to in vitro (inhibitory activity) tests by means of supercoiled DNA relaxation techniques and were shown to display inhibitory activity against human DNA topoisomerase II-α at 50 µM. Interconversion of these two pigments under the mild conditions of the isolation techniques should be highly unlikely but cannot be entirely ruled out.

Phytochemical investigation of Wissadula periplocifolia (L.) C. Presl and evaluation of its antibacterial activity

A phytochemical study on the aerial parts of Wissadula periplocifolia using chromatographic techniques has led to the isolation of sitosterol (1a), stigmasterol (1b), sitosterol 3-O-β-D-glucopyranoside (2a), stigmasterol 3-O-β-D-glucopyranoside (2b), phaeophytin A (3), 13²-hydroxy-(13²-S)-phaeophytin A (4), phaeophytin B (5), 17³-ethoxyphaeophorbide (6), 3,4-seco-urs-4(23),20(30)-dien-3-oic acid (7), 3-oxo-21β-H-hop-22(29)-ene (8), dammaradienone (9a), and taraxastenone (9b). The isolated compounds were characterised by spectroscopic analysis. A preliminary assay to evaluate the antibacterial activity of W. periplocifolia extracts and fractions showed that the dichloromethane, ethyl acetate, and n-butanol fractions were active against Enterococcus faecalis.

Effects of nutrient impoverishment on phytoplankton biomass: a mesocosms experimental approach in a shallow eutrophic reservoir (Garças Pond), São Paulo, southeast Brazil

Nutrient impoverishment in mesocosms was carried out in a shallow eutrophic reservoir aiming to evaluate the nutrient removal technique as a method for eutrophication reduction. Garças Pond is located in the Parque Estadual das Fontes do Ipiranga Biological Reserve situated in the southeast region of the municipality of São Paulo. Three different treatments were designed, each consisting of two enclosures containing 360 liters of water each. Mesocosms were made of polyethylene bags and PVC pipes, and were attached to the lake bottom. Treatment dilutions followed Carlson's trophic state index modified by Toledo and collaborators, constituting the oligotrophic, mesotrophic, and eutrophic treatments. Ten abiotic and 9 biological samplings were carried out simultaneously. Trophic states previously calculated for the treatments were kept unaltered during the entire experiment period, except for the mesotrophic mesocosms in which TP reached oligotrophic concentrations on the 31st day of the experiment. In all three treatments a reduction of DO was observed during the study period. At the same time, NH4+ and free CO2 rose, indicating decomposition within the enclosures. Nutrient impoverishment caused P limitation in all three treatments during most of the experiment period. Reduction of algal density, chlorophyll a, and phaeophytin was observed in all treatments. Competition for nutrients led to changes in phytoplankton composition. Once isolated and diluted, the mesocosms' trophic state did not change. This led to the conclusion that isolation of the allochthonous sources of nutrients is the first step for the recovery of the Garças Pond.

Provenance, Isolation and Characterisation of Organic Matter in the Cochin Estuarine Sediment-“a Diagenetic Amino Acid Marker Scenario

Cochin estuarine system is among the most productive aquatic environment along the Southwest coast of India, exhibits unique ecological features and possess greater socioeconomic relevance. Serious investigations carried out during the past decades on the hydro biogeochemical variables pointed out variations in the health and ecological functioning of this ecosystem. Characterisation of organic matter in the estuary has been attempted in many investigations. But detailed studies covering the degradation state of organic matter using molecular level approach is not attempted. The thesis entitled Provenance, Isolation and Characterisation of Organic Matter in the Cochin Estuarine Sediment-“ A Diagenetic Amino Acid Marker Scenario” is an integrated approach to evaluate the source, quantity, quality, and degradation state of the organic matter in the surface sediments of Cochin estuarine system with the combined application of bulk and molecular level tools. Sediment and water samples from nine stations situated at Cochin estuary were collected in five seasonal sampling campaigns, for the biogeochemical assessment and their distribution pattern of sedimentary organic matter. The sampling seasons were described and abbreviated as follows: April- 2009 (pre monsoon: PRM09), August-2009 (monsoon: MON09), January-2010 (post monsoon: POM09), April-2010 (pre monsoon: PRM10) and September- 2012 (monsoon: MON12). In order to evaluate the general environmental conditions of the estuary, water samples were analysed for water quality parameters, chlorophyll pigments and nutrients by standard methods. Investigations suggested the fact that hydrographical variables and nutrients in Cochin estuary supports diverse species of flora and fauna. Moreover the sedimentary variables such as pH, Eh, texture, TOC, fractions of nitrogen and phosphorous were determined to assess the general geochemical setting as well as redox status. The periodically fluctuating oxic/ anoxic conditions and texture serve as the most significant variables controlling other variables of the aquatic environment. The organic matter in estuary comprise of a complex mixture of autochthonous as well as allochthonous materials. Autochthonous input is limited or enhanced by the nutrient elements like N and P (in their various fractions), used as a tool to evaluate their bioavailability. Bulk parameter approach like biochemical composition, stoichiometric elemental ratios and stable carbon isotope ratio was also employed to assess the quality and quantity of sedimentary organic matter in the study area. Molecular level charactersation of free sugars and amino acids were carried out by liquid chromatographic techniques. Carbohydrates are the products of primary production and their occurrence in sediments as free sugars can provide information on the estuarine productivity. Amino acid biogeochemistry provided implications on the system productivity, nature of organic matter as well as degradation status of the sedimentary organic matter in the study area. The predominance of carbohydrates over protein indicated faster mineralisation of proteinaceous organic matter in sediments and the estuary behaves as a detrital trap for the accumulation of aged organic matter. The higher lipid content and LPD/CHO ratio pointed towards the better food quality that supports benthic fauna and better accumulation of lipid compounds in the sedimentary environment. Allochthonous addition of carbohydrates via terrestrial run off was responsible for the lower PRT/CHO ratio estimated in thesediments and the lower ratios also denoted a detrital heterotrophic environment. Biopolymeric carbon and the algal contribution to BPC provided important information on the better understanding the trophic state of the estuarine system and the higher values of chlorophyll-a to phaeophytin ratio indicated deposition of phytoplankton to sediment at a rapid rate. The estimated TOC/TN ratios implied the combined input of both terrestrial and autochthonous organic matter to sedimentsAmong the free sugars, depleted levels of glucose in sediments in most of the stations and abundance of mannose at station S5 was observed during the present investigation. Among aldohexoses, concentration of galactose was found to be higher in most of the stationsRelative abundance of AAs in the estuarine sediments based on seasons followed the trend: PRM09-Leucine > Phenylalanine > Argine > Lysine, MON09-Lysine > Aspartic acid > Histidine > Tyrosine > Phenylalanine, POM09-Lysine > Histadine > Phenyalanine > Leucine > Methionine > Serine > Proline > Aspartic acid, PRM10-Valine > Aspartic acid > Histidine > Phenylalanine > Serine > Proline, MON12-Lysine > Phenylalanine > Aspartic acid > Histidine > Valine > Tyrsine > MethionineThe classification of study area into three zones based on salinity was employed in the present study for the sake of simplicity and generalized interpretations. The distribution of AAs in the three zones followed the trend: Fresh water zone (S1, S2):- Phenylalanine > Lysine > Aspartic acid > Methionine > Valine ῀ Leucine > Proline > Histidine > Glycine > Serine > Glutamic acid > Tyrosine > Arginine > Alanine > Threonine > Cysteine > Isoleucine. Estuarine zone (S3, S4, S5, S6):- Lysine > Aspartic acid > Phenylalanine > Leucine > Valine > Histidine > Methionine > Tyrosine > Serine > Glutamic acid > Proline > Glycine > Arginine > Alanine > Isoleucine > Cysteine > Threonine. Riverine /Industrial zone (S7, S8, S9):- Phenylalanine > Lysine > Aspartic acid > Histidine > Serine > Arginine > Tyrosine > Leucine > Methionine > Glutamic acid > Alanine > Glycine > Cysteine > Proline > Isoleucine > Threonine > Valine. The abundance of AAs like glutamic acid, aspartic acid, isoleucine, valine, tyrosine, and phenylalanine in sediments of the study area indicated freshly derived organic matter.

Seasonal variation of biomass and productivity of the periphytic community on artificial substrata in the Jurumirim Reservoir (São Paulo, Brazil)

The seasonal variation of the periphytic community attached to an artificial substratum (glass tubes) was studied during two different periods in a lagoon connected to the Paranapanema River, the main tributary of the Jurumirim Reservoir (São Paulo-Brazil). An analysis of dry weight, ash free dry weight, chlorophyll a, phaeophytin and primary productivity of periphyton was carried out. The first experiment lasted from August to December 1993, the second from February to June 1994. Tubes were removed after 7, 14, 21, 28, 60, 90 and 119 days of incubation. In the 1st experiment, the periphytic community reached a higher biomass after the 4th week of colonization (28th day), in the 2nd experiment after the 2nd week (14th day). This discrepancy is related to seasonal differences in environmental factors (water temperature, nutrients concentrations and water discharge) that determine initial colonization. After the first stages of colonization, the biomass and primary productivity of periphyton reached their maximum values after the 60th day of incubation. In both experiments, three developmental phases could be discerned. In the initial phase, an exponential growth was observed. In the second phase, the bioderm reached its maximum biomass and productivity. In the third phase, a decrease of biomass and productivity occurred.

Periphyton on natural substratum in jurumirim reservoir (São Paulo, Brazil): Community biomass and primary productivity

Seasonal variation in the biomass and primary productivity of the periphyton on natural substratum (internodes of Echiiwchloa polystaclya HBK Hitch.) was studied during one year (from August 1993 to July 1994) in a lagoon with permanent connection with a river. We also analysed the relationships between the hydrological regime, climatic conditions and physico-chemical variables of water with the biological compounds of the periphyton. Values of dry mass, ash-free dry mass, chlorophyll a and phaeophytin of periphyton ranged from 0.55±0.24 g m-2 to 7.86±4.93 g m-2; 0.28±0.18 g m-2 to 3.72±2.23 g m-2; 0.57±0.09 mg m-2 to 15.57±4.52 mg m-2; 0.03±0.03 mg m-2 to 4.74±3.46 mg m-2, respectively. The primary productivity of periphytic algae measured by C14 method ranged from 6.45±1.29 mg C m-2 h-1 to 52.88± 7.55 mg C m-2 h-1. The biomass showed a peak in October 1993, February and April 1994. Higher value of primary productivity was recorded in December 1993 and January 1994 and was due to the peculiar light and nutrition conditions during this period. We conclude that biomass and productivity of the community are controlled mainly by hydrological regime (fluctuations of water level). © INTERNATIONAL SCIENTIFIC PUBLICATIONS.

Phytoplankton primary productivity in an urban eutrophic reservoir (São Paulo, Brazil)

The aim of this study was to analyze temporal ..d vertical variation of the biomass and of phytoplankton primary productivity in an urban eutrophic reservoir, in relation to the physical and chemical characteristics of the water. The physical and chemical variables of the water were defined in the limnetic region of the reservoir, at depths of 0.0; 0.5; 1.0; 2.0; 3.0 and 4.0 meters. Three samples were taken to define both the physical and chemical variables, concomitantly with the biomass (chlorophyll-a and phaeophytin) and phytoplankton primary productivity (C-14 method). Based on data obtained on differences in depth of the mixture zone and the euphotic zone, it is hypothesised that, depending on the time of the year, phytoplankton is conditioned by differences in the light and nutrient regimes, which change according to the constant loads of nutrients thrown into the system. The highest concentration of chlorophyll-a in the photic zone of the limnetic region was observed in November 2000 (1,197.3 mg Chl L -1) and the lowest in November 1999 (94.0 mg ChI L -1), whereas the profiles of primary activity of phytoplankton presented the highest rates on the surface of the water column, with values varying from 84.7 (May 2000) to 1,376.7mg C m -3 h -1 (December 2000). Annual primary productivity was calculated at 1,567.0gC m -2y -1, considered euproductive. The primary productivity profiles reported in this study are typical of aquatic eutrophic systems, rich in plankton and with low light penetration. It can be stated that Garças Lake is a system that suffers from anthropogenic impact, through receiving large loads of organic pollution, reflecting on the physical and chemical characteristics of the water and on the high values of biomass and primary phytoplankton activity. © National Institute of Ecology, New Delhi.