Sunday, June 6, 2010

ALGAL POLYPHENOLICS

By : Elfahry Bimantara

Polyphloroglucinol phenolics are the best known example of chemical deterrents against herbivores in temperate marine systems. However, most of the research on these compounds has been done in North America, where phenolic levels in algae are often low. I show here that algae in the Orders Fucales and Laminariales in temperate Australia and New Zealand typically contain very high levels of polyphenolics-much higher than species in these orders in North America. The median value for the distribution of mean phenolic levels for 25 North American species is 1.33% total phenolics (dry wt.); for 37 Australasian species, the median is 6.20%. Significant spatial, temporal, and intraplant variation in phenolic content occurs in a number of species in Australasia, but this does not significantly alter my major conclusion.

Phenolic levels in drift algae (an important food source for some herbivores) detached for up to two weeks are also not significantly different from living, attached plants. Many species in the Fucales in Australasia also contain non-polyphenolic secondary metabolites that are not found in North American species. Thus herbivores in Australasia face greater amounts, and a greater range,of putative chemical defenses in brown algae than do herbivores in similar systems in North America. Any general theory for the evolution of marine plant/herbivore interactions must take into account such broad-scale biogeographical (and taxonomic) patterns.

The diversity and intensity of selection pressure on organisms has been described as varying predictably across biogeographic zones, generally increasing with decreasing latitude. Apparent effects of this increased selective pressure in the tropics include patterns in species diversity (Pianka 1966), diversity and quantity of allelochemicals (Bakus and Green 1974; Levin 1971, 1976; Levin and York 1978; Hay and Fenical 1988; Coley and Aide 1991; Hay and Steinberg in press), predation intensity, inferred antipredatory morphological structures (Vermeij 1978; Jeanne 1979; Bertness et al. 1981; Heck and Wilson 1987) and herbivory (Levin 1976; Lubchenco and Gaines 1981; Gaines and Lubchenco 1982; Steneck 1988; Hay and Steinberg in press). In the marine environment, herbivory is most intense at low latitudes (Vermeij 1978; Lubchenco and Gaines 1981 ; Steneck 1988 ; Hay and Steinberg in press). Algal chemical defenses generally Offprint requests to: N.M.

Targett parallel this latitudinal variation in herbivory with increasing concentration and diversity of allelochemicals with decreasing latitude (Hay and Fenical 1988; Hay and Steinberg in press). Phloroglucinol-based polyphenolics (phlorotannins, see Ragan and Glombitza 1986), antifeedant allelochemicals which occur exclusively in brown algae (Phaeophyta), have been reported as an exception to this trend, increasing in concentration with increasing latitude (Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg et al. 1991 ; Steinberg and Van Altena in press).

This is in contrast to terrestrial data on condensed tannins for broad leaved forest species, which show that temperate species have lower phenolic concentrations than tropical ones (Coley and Aide, 1991 and references therein). In marine temperate regions, where considerable data exist on phlorotannin concentrations, brown algae are characterized as either high or low phenolic species. High phenolic species are defined as those with phenolic concentrations > 2% of their dry weight, the threshold level at which herbivory is typically deterred (Swain 1979; Geiselman and McConnell 1981 ; Steinberg 1988). However, a high degree of inter- and intraspecific variability in phenolic concentration has been observed (Ragan and Glombitza 1986; Steinberg 1986, 1988, 1989).

Phenolic concentrations in tropical phaeophytes have been reported only from Indo-Pacific species; therefore, a less complete picture is available for tropical than for temperate browns (Hay and Fenical 1988; Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg 1986, 1989; Steinberg et al. 1991 ; Steinberg and Van Altena in press). In the Indo-Pacific, phenolic concentrations have been found to be low, although Padina spp. from Magnetic Island, Australia (Steinberg et al. 1991) and individual plants in two other genera (Lobophora and Dictyopteris) were noted as exceptions (Steinberg and Paul 1990). Although brown algal phenolic concentrations have not been determined for any Caribbean species, patterns of herbivore preference have been used to suggest that polyphenolics might be high in some species (Norris and Fenical 1982). We examined phenolic levels in tropical phaeophytes from both the Caribbean and western Pacific and in selected species from the temperate western Atlantic and eastern Pacific (i.e. both coasts of North America). These levels were compared to literature values to determine: 1. Are there latitudinal trends in phenolic concentrations? 2. Are there interoceanic differences between tropical Old World (Indo-Pacific)and Neotropical (Caribbean) phaeophyte phenolic concentrations? 3. Does the magnitude of intraspecific phenolic variability in tropical and temperate phaeophytes overshadow observed latitudinal trends?


Tropical Species
The Caribbean phaeophytes (orders Fucales and Dictyotales) that we examined had phenolic concentration levels ranging from 1.34% to 14.92% dry weight. Caribbean Fucales all had high phenolic concentrations (> 2 %) and tested positive for phloroglucinol derivatives. Two of the four Caribbean Dictyotales examined (Stypopodium zonale and Lobophora variegata in each of its three forms, Coen and Tanner 1989) also had high phenolic concentrations. The dry weight phenolic concentration values for the Lobophora forms and for Stypopodium (8.33% 13.39% and 14.92% respectively) far exceeded all previously reported values for species in this order. Thus, our data from Caribbean phaeophytes in which six of eight species produced phenolic concentrations in excess of 2% (3.37%-14.92%) show that high phlorotannin concentrations are not limited to temperate species. Tropical interocean differences are evident when comparing phenolic concentration values for phaeophyte genera common to the Indo-Pacific and Caribbean. Lobophora variegata, the only species examined in this study that is common to the tropical areas listed, showed low phenolic values for Pacific (0.81%, Hawaii, Table 1) and Indo-Pacific (<2%, p="0.006)," p="0.002)"> 2% dry weight), while species in the orders Laminariales and Dictyotales typically have low levels (Steinberg 1985, 1989; Ragan and Glombitza 1986; Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg et al. 1991 ; Steinberg and Van Altena in press). Earlier studies also show that polyphenolic levels in tropical Fucales and Dictyotales from the Indo-Pacific are low (Steinberg 1986, 1989; Hay and Fenical 1988; Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg et al. 1991). Our results clearly demonstrate that species in the tropics can be high in phenolics. Data from our study and from the literature, where extraction and quantification procedures allow comparisons to be made, also indicate that intraspecific variability may be as high as interspecific variability. Of the phenolic values obtained, most striking were the values obtained for the three forms of Lobophora (Coen and Tanner 1989) and for Stypopodium (8.33-13.39% and 14.92% dry weight respectively). Phloroglucinol and a variety of phenolic acids have been reported from Lobophora variegata (form not specified) collected in Brazil (Legaz et al. 1985). Acetate-derived phenolic lipids have been described from Lobophora papenfussii (Gerwick and Fenical 1982) and their presence in Lobophora variegata (form unspecified) from the Florida Keys has been hypothesized (Paul and Hay 1986). However, higher-molecular-weight phlorotannins are also evident (Folin-Denis test, Lindt test, 1H NMR) in molecular sizing
experiments done on aqueous extracts from each of the three forms of Lobophora collected in Belize (Boettcher and Targett unpublished data). Fresh Stypopodium is known to contain a series of primarily mevalonatederived low-molecular-weight phenolic metabolites (<> 100,000Da (Boettcher and Targett unpublished data).

The absence of a latitudinal phlorotannin trend between Caribbean tropical and temperate phaeophytes and the presence of site-specific phlorotannin variability within species suggests that other factors may play a more critical role within a biogeographic region in determining phenolic concentrations. Variability in phenolic concentration may be influenced by extrinsic factors such as salinity (Ragan and Glombitza 1986), nutrient availability (Ilvessalo and Tuomi 1989), herbivore intensity (Van Alstyne 1988) and season (Ragan and Jensen 1978 ; Ragan and Glombitza 1986). Intrinsic plant factors such as size (Denton et al. 1990), age (Pederson 1984), and tissue type (Steinberg 1984; Tugwell and Branch 1989; Tuomi et al. 1989) may also play a role. The magnitude of the variation in phenolic concentration is often high enough to alter the palatibility of plants to herbivores (Swain 1979; Geiselman and McConnell 1981; Steinberg 1988). Studies regarding the effect of plant phlorotannin concentration on marine tropical herbivores have yielded conflicting results. Van Alstyne and Paul (1990) showed that phlorotannins from temperate species are effective deterrents against some tropical herbivores when they are incorporated into tropical analogues at concentrations > 2% dry wt, while Steinberg et al. (1991) showed that quantitative variability in temperate and tropical algal phenolic levels do not correlate with the susceptibility of these algae to herbivory. These and other studies make supportive arguments based upon the assumption that all tropical phaeophytes are typically low in phenolics and invoke physiological and cost arguments as explanations for their low concentrations (Steinberg 1986; Hay and Fenical 1988; Van Alstyne 1988; Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg et al. 1991; Hay and Steinberg in press; Steinberg and Van Altena in press). Our study shows that phenolics can be present in high and variable concentrations in tropical Caribbean phaeophytes, and thus the assumption that phlorotannins are of little consequence in tropical marine plant-herbivore interactions because of their low concentrations (Steinberg 1986; Hay and Fenical 1988; Van Alstyne 1988; Steinberg and Paul 1990; Van Alstyne and Paul 1990; Steinberg et al. 1991) is premature. 
 
 
Our results in combination with previously published data suggest that there is an interoceanic difference between phenolic concentrations in tropical Indo-Pacific phaeophytes and Caribbean phaeophytes. Grazing intensity is higher in the Pacific and Indian oceans than in ecologically similar communities in the Atlantic (Vermeij 1978; Estes and Steinberg 1988; Steinberg and Van A1-tena in press). Grazing intensity thus correlates negatively with our observations of phaeophyte phenolic concentrations and calls into question the role of phlorotannins in defense. However, other extrinsic and intrinsic factors may confound the interpretation and should be examined (Bernays et al. 1989). To explain these differences and those in temperate and tropical marine plant-herbivore interactions, it is now evident that more subtle within-plant (Zucker 1983; Gaines 1985; Lewis et al. 1987; Coen and Tanner 1989) and among-herbivore (Gaines 1985; Hay et al. 1987; Horn 1989) characteristics must be examined. These include phenotypic variation in phenolic concentrations, phlorotannin size distributions, induction of phenolics by herbivores, as well as herbivore features such as gut pH and the presence of gut surfactants. Studies such as these will allow a further comparison between the importance of biological/physical factors and geographic distribution in determining phlorotannin concentrations.

Reference From : El_fahrybimantara and others

Sunday, April 18, 2010

The Bonsai Hunters


Hunters among the bonsai has a great share in determining the future of Indonesian bonsai. Therefore they need to continually broaden and increase their knowledge of bonsai.

This was conveyed by Wahjudi D. Atopic Dermatitis in a monthly meeting organized by the Branch PPBI Probolinggo at home Kian Fuk, Kraksaan, Sunday (29 / 6). More than 60 people bonsai enthusiasts from Probolinggo, Situbondo and Bondowoso present at a special meeting room in the middle of the garden's bonsai. Besides Wahjudi, appearing as a speaker is Sigit Margono, sculpture instructor from Malang, and also Sulistiyanto Suyoso, which provides training bonsai demo.
When asked the question who the bonsai hunter, did much to raise my hand. That's why Wahjudi then gave a special message on the hunter. Because, so far there are still hunters who break down the origin of the wild tree stump. They did not consider whether the tubers are indeed going to be qualified as a bonsai.
There's even assuming that the bonsai is grown on or pinched stone deems as qualified bonsai. They struggled to break the boulder just to get a bonsai which she thought was going to sell expensive. In fact, the value may be regarded as going low. And when asked about the price, then peg the number of millions of rupiah. Of course, bonsai enthusiasts who understand the objection to buy it.
Bonsai gonna like it was simalakama. They offer a good price because it was hard to find, it took no little cost and time consuming. But certainly not about the price associated with it all. Price is determined by the quality bonsai equipment. Not to mention that nature had already damaged by pendongkelan bonsai finally going to waste it.
So, how can know that bonsai gonna have a good quality or not? This question is still often arise from the beginner hobbyist. Sulistiyanto replied, "that's certainly going to be an important first life." There is no point going to be good if it had only to continue his life in a pot failed.
In addition, Sulis said, note the shape, direction of motion or rhythm, and also his character. There are bonsai which have a strong character, but there are soft. All this really needs its own art sensibilities. There is a kind of sense to be able to find out whether or not going is beautiful. Not only sense, but also the talents (talent) and insights from the artists bonsainya.
Although, any form of bakalannya, a bonsai artist seemed to get a challenge to make a beautiful bonsai. Only if the natural form is good, then to be beautiful just need some accessories only.
Dicontohkannya, if there's going straight bonsai towering stand upright like a person, then the concern is the face. Not that going to something like that can not be made into a good bonsai. What if his pose is made slightly tilted slightly. Then there are like hand gestures to the side as people posed for pictures taken. Hand movement (read: a branch or branches) that had caused its own rhythm. - Henri nc

From GREEN Hobby Magazine No. 12-2008

Monday, April 5, 2010

Eclipse of Twilight Saga

This is the nice recommended film this month. This is Twilight Saga: Eclipse, the third sequel of twilight saga after the first sequel of Twilight and the second sequel, Twilight Saga: new moon. Like before, this movie is starred by 3 main characters, Edward Cullen (Robert Pattinson), Bella Swan (Kirsten Stewart), and Jacob Black (Taylor Lautner).

What is the main description of this film? This film is about 3 main characters of role. But, this film gives more attention to some secrets that will be known by the viewers about Warewolf Legend, Imprint (Like life mate be known since first sight for warewolves).
Well, the main of this movie is the allying of vampires and warewolves to destroy the wicked riotous thirsty-blood young vampires that is "created" by Victoria because of revenge to Bella in James death, her mate vampire.
The young vampires are so horrendous and many victims killed due to their presence. When the young vampire knight had enough power, they plan to attack Cullen's family and kill Bella to wreak Victoria's revenge. But, the plans could be known by Alice that has the superiority to read the future and mind so that the war between Vampires is avoided.
Before, Cullen's family considered to ally with Jacob Black and friend as warewolves to destroy the wicked young vampires. What about the next story? You can watch this interesting movie in the nearest movie in your town.

Thursday, January 21, 2010

Cool Games

Games are one of the most people play during the break. Almost people fulfill their break time with playing the games. The games will melt away the tired and the bored in your mind. So, if you are so tired because of your routine activities, you can play the games in your PC. You can also play the online games. If you are addicted with the games, you will always look for the new games in many sites. You think that game is your life. So, your life could not be separated with the games. How can you get the attractive games? Do you know the best sites for it? Well, you can find many attractive games in play cool games.

Play cool games provide many attractive games within. You will be surprised because you will find the new games that you don’t play it yet. Many types of games you can get in play cool games, such as adventure, fighting, action, until the sport games. You will not be bored with the games there. You will always be happy because of the attractive games. Therefore, your break time will not be useless because you fulfill it with playing the attractive games. Your life will always be excited with the challenges of the games.

Wednesday, January 6, 2010

3 D of Titanic Film

The news of the Titanic 3D version release is so far so hot. One of the site film is USA wrote it (8/7/2010). It is written that Fox Film Company and James Cameron, the producer of the most success film will release Titanic with 3D format.
Fox and Cameron said that this film would be released at least in April 2012. That time marks the 100th of RMS Titanic Cruise that begun the cruise pass through Atlantic Ocean 12-14 April.
The plans of the re-production of Titanic with 3D format are revealed in the 100th of Gloria Frances Stewart (Gloria Stewart) event celebration at 4 July several days ago. Gloria Stewart is actress that began her career in entertainment, especially film since 1923. She role as "Old Rose" in Titanic (1997) that also stared by Kate Winslet and Leonardo DiCaprio.
If this film success, it is not impossible for Fox and Cameron to re-release the other fantastic films in 3D format. The try out projects is desired can be "machine money" for this film company.