Haematococcus pluvialis (say it three times fast!) is an extraordinary algae. It can crank out a fabulously powerful and widely sought-after antioxidant called astaxanthin, that retails for about $70,000.00 per kilogram. HP also has an interesting and complex lifestyle; when its cells are well-fed and healthy, they are bright green, and swim about by means of a pair of flagella; when times get tough, though, such as when their puddle dries up, they transform themselves radically, into non-motile, perfectly spherical cysts of a rich red color. Thus their name, which means “blood cells of the rain”.
Haematococcus pluvialis in our lab.
The red form is very hardy, and can withstand drying out; the red color comes from the astaxanthin, which seems to protect the cell during this time.
There are only a limited number of strains of HP commercially available, so it is interesting to seek new ones out; thus, when my algae wizard friend stumbled on an image of a stone hollow in the California hills, filled with a blood-red liquid, it struck our interest, particularly because the hollow was of Native manufacture, and in an obscure place of great anthropological significance. This was the Lost City of the Volvons, purportedly the largest settlement on the West Coast prior to the arrival of the Spanish. The stone hollows were their mortars (as in mortar & pestle), used to grind acorns into a lovely mush, edible after submersion in the nearby stream for a few days, to leach out the tannins.
The idea that in the process this native people – the Volvons – had inadvertently (?) created some very long-term Haematococcus habitat, perhaps even a particular Volvonic strain, was sufficiently intriguing to prompt a collaboration in locating, visiting, and ultimately sampling algae from this lost ancient city.
Setting out on our algae adventure…
We knew that the city was somewhere in the vicinity of Mount Diablo; after some sleuthing we found a likely area, and hiked out there, through oak groves on grassy hills, clambering over boulders and streams. And under a tree, we found our first mortars (see image), and imagined Volvon women with tule reed baskets full of acorns, grinding their staple food happily, before the arrival of Europeans who would take away their land and almost erased their existence.
We stumbled among the rocks, ravines, and trees for a while, without finding anything that could be interpreted as urban. All the mortars were dry, or full of water cold and painfully clear.
Two months later we tried again, armed with a better notion of where the city stood, and the hope that warmer temperatures would prompt the growth of the precious algae. Getting to the putative city site involved jumping a fence or two, into questionable territory, but then there it was – an array of mortars far beyond anything we had seen before. And wasn’t the goop inside some of them distinctly reddish? We gathered samples, and brought them back for culturing.
Collecting samples from Volvon mortars.
But then, lo and behold, in a tiny pool in a sink left in our backyard (due to an oft-delayed remodeling project), brilliant red exploded. The cells inside were classic Haematococcus, green swimmers plus plump red cysts. It grew robustly in our flasks, and the Sobrante Sink strain (shown above) was born, perhaps with a wisp of Volvon magic.
Blood-red miracle in an abandoned sink.