The Harvest of Marine-derived Cosmetic Ingredients: A Case Study of Pseudopterogorgia elisabethae

Editor’s note: With the continuing trend for sustainable sourcing in cosmetics R&D, the following article offers a case study on the research conducted for and harvest methods of a particular marine-derived cosmetic ingredient, Pseudopterogorgia elisabethae. While less technical in nature than typical Cosmetics & Toiletries articles, it is intended to provide insight into one sustainability model to assist product developers following this path.

Coral reefs are one of the oldest and most biologically diverse eco- systems on earth. They support hundreds of thousands of plant and animal species, protect coastlines, provide food and form the basis of local economies for millions of people. The annual net benefit of coral reefs is more than US$1 billion in the United States, and their estimated value globally is US $30 billion.1 Unfortunately, coral reefs are sensitive ecosystems. A combination of direct and indirect anthropogenic effects in concert with natural events has led to decades of decline in reef health. As much as 70% of the world’s coral reefs may be lost by 2050.2

Human interference with coral reefs has been both direct and indirect. Overfishing, destructive fishing techniques, pollution, introductions of invasive species and land use policies that affect coastal water quality have all had adverse effects on reefs. On a larger scale, long-term changes in water temperature and ocean acidity are affecting and will continue to affect coral reefs. Moreover, the effects of natural events, such as hurricane damage and disease outbreaks may be amplified on reefs that have weakened ecosystems. Some of these effects are chronic and cumulative, while others only appear when a critical breaking point is reached. For example, large fleshy macro algae have always been a constituent of coral reef communities, but they have reached high abundances on many reefs, and the algae interfere with the survival and growth of corals and may have altered the long-term survival of coral reef communities.

The complexity of coral reef ecosystems, the diverse array of threats affecting reefs and the limited information on them makes it difficult to measure the effect of a single threat or event, but it is clear that the persistence of coral reefs will require careful management of direct human interactions with reef ecosystems as well as changes in global scale practices that affect climate change.

A significant component of the value of reef ecosystems is that they are the source of a variety of extractable resources. The development or maintenance of sustainable practices for the harvesting of those resources is equally important to reef health. The aim of this paper is to review the harvest practices carried out by these authors as associated with the utilization of the octocoral Pseudopterogorgia elisabethae, and to discuss the harvest, knowledge and nature of research required to ensure the sustainability of the species.

P. elisabethae in Personal Care

P. elisabethae extract (INCI: Sea Whip Extract) has been used for nearly two decades in cosmetic and skin care preparations for its unique benefits. For example, studies conducted in the early 1980s revealed that P. elisabethae contains significant quantities of polar lipid metabolites that carry biological activity. That research, which required limited collections for study, was conducted by a group of scientists from the University of California and resulted in the discovery of a family of diterpene glycosides named pseudopterosins.3 One of the pseudopterosins in P. elisabethae, pseudopterosin A, was found to possess anti-inflammatory and analgesic activities. An in vivo academic study found that pseudopterosin A demonstrated 50 times the ability of the non-steroidal anti-inflammatory drug indomethacin when applied to mouse skin. The mechanism of action of pseudopterosin A was believed to be through the inhibition of phospholipase A2, an enzyme that cleaves arachidonic acid from the cell membrane and makes it available to intracellular events that participate in the inflammation cascade.4

Pseudopterosins extracted and purified from P. elisabethaea have been incorporated into skin care products to treat and protect skin. For example, one human panel study utilizing Laser Doppler techniques to assess its effect on ethyl nicotinate-induced skin inflammation demonstrated both a significant retardation effect and mostly preventive effect of the induced inflammation.5 Considering its benefits to personal care yet its fragile origin, P. elisabethae serves as an interesting case study toward the development of sustainable cosmetic raw materials. Since the harvests initially began in 1995, the actives level in P. elisabethae, which is approximately 4%, did not vary.

P. elisabethae: The Species

Before considering harvesting P. elisabethae, to ensure it would re-grow and that any reduction in its presence would not disrupt the ecological balance, it was first crucial to understand the species’ basic behavior and reproductive mechanisms. P. elisabethae is a branching octocoral or gorgonian coral. Unlike hard corals, branching octocorals do not produce a solid calcium carbonate skeleton but rather a proteinaceous axis that gives the colony its branching form.6 Octocorals are common, often dominant members of the reef community, and although they do not produce the rigid structures that define the reef, like the hard corals, they provide habitat for a wide variety of fish and invertebrates. P. elisabethae is distributed throughout the Caribbean and is often abundant at depths below 10 m on reefs ranging from the Bahamas and Florida to Colombia.7 The species is common on both reefs and on an associated reef habitat usually referred to as hard ground.

P. elisabethae’s pattern of growth follows a presumably genetically controlled program that generates the characteristic featherlike appearance of branches. 8 However, colonies vary in appearance within and among populations both morphologically and genetically.9 In addition, like most other reef corals, P. elisabethae lives in a mutualistic association with symbiotic dinoflagellates (algae) of the genus Symbiodinium.10 These algal symbionts are collectively known as zooxanthellae.

As is the case for most octocorals, relatively few reef species feed on P. elisabethae, an outcome that is probably linked to the presence of noxious biological metabolites that are produced by the colony. While most grazers avoid octocorals, a number of fish, snails and other invertebrates feed on octocorals including P. elisabethae. However, no species is known to specialize and thus depend on P. elisabethae alone. The amount of P. elisabethae consumed by these species is probably directly related to the abundance of the octocoral, but changes in P. elisabethae abundance alone probably has a negligible impact on other species.

Harvesting P. elisabethae

It is important to understand the impact of the harvest on the size and number of colonies. Therefore, starting in 1998, research on the sustainability of P. elisabethae in relation to its harvest initially focused on the patterns of growth in colonies in order to determine how pruning would affect growth and how the survival and recovery of colonies could be optimized. Additional efforts examined reproduction of the colonies and the growth of populations in order to assess the effects of the harvest on the longer term maintenance of harvested populations.

As noted, P. elisabethae colonies were found to grow in featherlike branches that occur singularly or in a larger, bushlike shape. The growth pattern demonstrates that if not cut too low, P. elisabethae can re-grow and expand. Their growth follows a plan where branches are initiated at specific locations, grow to some length and then stop. Early data collected by divers validated the collection scheme that the harvesters had developed from their own observations. Specifically, P. elisabethae is harvested by divers at select locations in the Caribbean who have been trained to recognize the species and to harvest colonies in a manner that allows re-growth. The divers use either scuba or surface supplied air, which functionally limits the depth to which the material can be harvested. Once collected, the material is brought to shore, dried in the sun and processed to extract active compounds. Although colonies can be taller, P. elisabethae are commonly 30–60 cm in height, and the harvesters prune colonies to leave branches that are approximately 8 cm tall or higher and contain at least six branches to ensure re-growth (see Figure 1).

The site of pruning on the harvested colony heals in several days, and subsequent growth includes both extension of the remaining branches and generation of new branches. If pruned too small, colonies do not survive clipping or exhibit reduced growth, but beyond that constraint, pruned colonies recover and grow. Interestingly, actively growing branches from previously harvested colonies appeared to have greater growth rates than unharvested colonies.12 Overall, the growth of colonies slowed as they reached the maximum size for their species,11 and the re-growth of colonies was found to be variable but in exceptional cases, exceeded 10 cm per year (see Figure 2).

In a preliminary attempt to model the harvest of P. elisabethae, S Goffredo and HR Lasker12 fitted available data to a commonly used fishery model, the Beverton-Holt model, to estimate how often colonies should be harvested. This model addressed the issue of how long to allow colonies to grow prior to harvest. Based on data from P. elisabethae in the Bahamas, the model suggested that production would be optimal if colonies were allowed to grow to 21–28 cm tall, which corresponds to an age of 7 to 9 years in a natural population. Translating that result into a management strategy will require additional data sets.

As noted, colonies are not removed in the harvest, thus it is critical to determine the proportion of the harvested colonies that survive and then how rapidly they grow to a harvestable size. The harvesters’ observations have been that populations that had been harvested generally underwent enough growth and re-growth to support commercially viable harvests after three years. The longer-term sustainability of the harvest, however, is dependent upon recruitment, the settlement, survival and growth of larvae, to replace colonies that die; thus, data on recruitment and the effects of the harvest on recruitment will be essential data in future assessments of the harvest.

Pruning colonies reduces the number of recruits produced by the population and may reduce the steady state of the supply of new colonies.12 Therefore, populations that are harvested too often may slowly decline in abundance as older colonies naturally die. This effect may be mitigated by the presence of colonies below the 20 m and shallower depths that the harvesters usually work in, and because harvesting invariably leaves small areas and colonies undisturbed.

For example, in surveys of sites that had previously been harvested, declines in abundance suggested that at some sites more than 50% of the colonies had not been harvested. In order to minimize the effects of pruning, the harvest that had originally been conducted at three-year intervals per location is now conducted at five-year intervals. This provides colonies with additional years of reproduction prior to harvest.

A complete quantification of these varying effects has not been undertaken, but harvesting has been conducted for almost two decades, and the yields provide some indication of the effects of the harvest. Harvest for commercial purposes has always been conducted under tight control using practices to ensure re-growth and maintenance of the supply. Here, the history of harvesting at a single site on hard ground in 7–20 m of water is reported.

The site of the harvesting covers an area of approximately 4 km2. This site was initially identified as an area with abundant P. elisabethae, and a small amount was harvested for research purposes in 1995. Commercial harvests were conducted in 1997, 2001 and 2005 (see Figure 3 and Figure 4). In addition, major hurricanes passed through the site in 1999 (Hurricane Floyd) and 2004 (Hurricanes Frances and Gene). Using 1997 as a baseline, it is evident in the chart that there was no decline in the amount of P. elisabethae harvested across the three harvests. Notably, the three hurricanes that swept over the site had no obvious effect on the P. elisabethae population, and their action of clearing algae from the substratum may have facilitated the successful settlement and survival of P. elisabethae recruits. Algal growth on Caribbean reefs may be the greatest threat to P. elisabethae and to corals in general. Alternate ways to harvest or grow the coral were not explored by these authors. Other research facilities have tried to synthesize the active compound but without success because of low yield and high cost.

Summary

In analyzing the data presented in this paper and review of additional unpublished data, a few conclusions can be drawn. First, the manner in which the colonies are clipped is a crucial factor in maintaining sustainable P. elisabethae populations. Also, equally important is the time interval between harvests. A period of four to five years provides time for the colonies to replace pruned branches and for the colony to reproduce and generate new recruits. Finally, the existing data is consistent with a harvest that is at or near a sustainable level. However, additional data is needed to assess the long-term impact on the harvested colonies and the survival of new recruits. Studies of populations that are to be harvested in the future can be used to provide this data.

A complete analysis may lead to further modification of the management plan. In the interim, the greater than 15-year history at the observed colonies’ specific locations, which allowed for alternate harvest sites, and the controlled practice of careful pruning by trained expert divers at controlled intervals bode well for the continued harvest of P.elisabethae.

Applying Sustainable Principles

In principle, any compound that is harvested from nature and not cultivated needs to be handled carefully as a resource. Its nature and habitats should therefore be studied, and a systematic approach should be managed to make sure that, as much as possible, the ecosystem balance is not affected. A few starting points should be understood such as population and distribution, pattern of re-growth and of course, as explained in the core of this paper—the effect of harvest on re-growth. This represents collaboration among representatives from the industry and academia and trained local fishermen.

References
1. HJS Cesar, L Burke and LPet-Soede, The Economics of Worldwide Coral Reef Degradation, Cesar Environmental Economics Consulting, Arnhem and WWF-Netherlands, Zeist, The Netherlands (2003) p 23
2. The Nature of Conservancy, www.nature.org/joinanddonate/rescuereef (Oct 2006)
3. SA Look, W Fenical, RS Jacobs and J Clardy, The pseudopterosins: Anti-inflammatory and analgesic natural products from the sea whip Pseudopterogorgia elisabethae, Proc Natl Acad Sci 83 6238–6240 (1986)
4. RS Jacobs and WH Fenical, Pseudopterosin and synthetic derivatives thereof, US Patent 4,849,410 (Jul 18, 1989)
5. N Dayan and R Sivalenka, Anti-inflammatory activity of pseudopterosins by laser Doppler blood flow evaluation, IFSCC Magazine 12(1) 17–22 (2009)
6. K Fabricius and P Alderslade, Soft corals and sea fans, Australian Institute of Marine Science, Townsville, Australia (2001)
7. C Gutiérrez-Rodríguez and HR Lasker, Reproductive biology, development, and planula behavior in the Caribbean gorgonian Pseudopterogorgia elisabethae. Invertebrate Biology 123 54–67 (2004)
8. HR Lasker, ML Boller, J Castanaro and JA Sanchez, Determinate growth and modularity in a gorgonian octocoral, Biol Bull 205(3) 319–330 (2003)
9. C Gutierrez-Rodrigues, MS Barbeitos, JA Sanchez and HR Lasker, Phylogeography and morphological variation of the branching octocoral pseudopterogorgia elisabethae, Mol Phylogenet Evol 50(1) 1–15 (2009)
10. SR Santos, C Gutierrez-Rodrigues, HR Lasker and MA Coffroth, Symbiodinium sp. associations in the gorgonian Pseudopterogoria elisabethae in the Bahamas: High levels of genetic variability and population structure in symbiotic dinoflagellates, Marine Biology 143 111–120 (2003)
11. S Goffredo and HR Lasker, Modular growth of gorgonian coral can generate predictable patterns of colony growth, J Exp Marine Biol and Ecol, 336(2) 221–229 (2006)
12. S Goffredo and HR Lasker, An adaptive management approach to an octocoral fishery based on the Beverton-Holt model, Coral Reefs 27 751–761 (2008)

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