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The joys of rice wine

30 December 2015 - How stuff is made

vietnamRiceWine You cannot escape rice wine when on vacation in Vietnam, it is staple tourist stuff but also cheaper than beer. It is mass-produced by local farmers despite government attempts to have it banned (link). Rice wine is a topic in serious scientific research! see here end here. Question is: how is it made?

The specialists agree you ferment rice with a special kind of yeast to a rice/water/ethanol mix and then you can either distil the brew to get to the wine or you can separate rice from wine by filtration. Problem is that the installation I have happened to witness (on the Sapa hiking trail in northern Vietnam) does not do either. In image 1 a large vat containing water and rice is heated in a wood-fueled kiln. Cold water is constantly added from the top and removed to the left. On the right a metal pipe leads away from the vat into a plastic drum. It produces clear rice wine! No distillation involved or filtration. Strange. The second vat by the way behind vat number one with the wooden stick in it contains fermented rice. The local rice wine is sold in second-hand PET water bottles. But what is the alcohol percentage? The local experts (fellow Australian and Canadian hikers) estimated the alcohol content was at least 20%. The scientific studies already mentioned explain that by simple filtration the percentage is 10% at the most (distillation will get you to 30%). The worrisome thing is that this amount of alcohol is not enough to preserve the wine so in an artificial way additional ethanol must be added. You may hope then that the local farmer (not rich) has a reliable ethanol supplier.

So the question as what the original alcohol percentage is, remains open, chemists should of course always carry a basic chemistry kit with them while on vacation but I forgot mine. So can the next chemist venturing into the Sapa region report back some accurate numbers? Thanks!

By the way, deep down south in the Mekong delta even plastic bottles are too fancy a container for storing rice wine. A plastic bag and a chopstick will do just as well! To dispense the wine just briefly raise the chopstick to allow the wine to flow out. Remarkably accurate. Something for the laboratory?

Antroquinonol A is not what it seems

23 December 2015 - Total synthesis

Baran 2015 Antroquinonol.PNGJust as easy as total synthesis was laid to rest in the last episode of this blog - sorry pointless, time to move on - The Baran lab this week makes a clear case to continue business as usual: total synthesis is important! Case at hand: what the hell is in Taiwanofungus camphoratus that makes it the fantastic medicinal mushroom that it is. Golden Biotech Corp has been certain the active ingredient is antroquinonol A and is currently running clinical trials. But is it? The Baran lab produced pure gram-scale (+)-antroquinonol A via classic total synthesis (Villaume et al. doi) and did some clinical laboratory trials of it's own. Main conclusion: antroquinonol A nor one of its main metabolites did show any antitumor activity.
In chemistry land these must be exiting times. If antroquinonol is not the active ingredient then what is? Dozens of chemistry labs must by now have joined a new race. Cancel all Christmas holidays!

With thanks to Fluorogrol for the alert (@Twitter)

The truth about total synthesis

17 December 2015 - TotSynth

An interesting comment in the latest issue of Nature by Philip Ball titled "Chemistry: Why synthesize?". His take on total synthesis is of particular interest. The pros and cons of total synthesis are continuously debated in the blogs and on twitter with consensus definitely heading towards "utterly pointless" but mainstream chemistry thus far has been silent. Total synthesis top gun K. C. Nicolaou has many a review and essay on the topic to his name but none of them stand out for intellectual content. Reads more like an erupting database.

So what is Ball's take on total synthesis? "Today, most wholly synthetic routes to complex natural products are too complicated to be useful in themselves to the pharmaceutical industry" but the efforts at least serve "to equip students with the practical skills that industry requires". Also "some chemists feel that total synthesis of large and complicated natural products has now become a scaling of peaks just because they are there ? with, moreover, a meaningless race to the summit that is often won by brute force" To make things worse "If you want to make a complicated molecule, do you really need an army of dedicated graduate students working through the night? Or could it be done by machine?" According to Ball there is no need to worry that automation will kill total synthesis as an art form. It is a done deal, the same thing has already happened to the art of playing chess.

One strong argument in favour of total synthesis I find lacking in Ball's comment. The importance of reliable reagents. Hundreds of reagents for the same purpose (oxidation, reduction) exist and new ones get invented every week. But which one to choose for your next project? You can be sure a researcher contemplating a reagent for step 101 of a 102 step total synthesis with just 1 milligram left will pick the most reliable one in terms of conversion, selectivity and ease of work-up. The fancy new reagent recommended by the supervisor or a best friend will be ignored, even plain bribery will not help. If the reagent does not perform who wants to spend months repeating step 1 to 100?

The Elsevier War ends here

16 December 2015 - The Art of Publishing

As reported here earlier, the Dutch universities declared war on scientific publisher Elsevier in 2015 (link, link) demanding an affordable open access model. This war has now ended in an agreement.

The good news: Dutch researchers can now publish their articles open access without any costs. In this way by 2018 the universities predict that 30% of all Elsevier articles are published via open access. End of story? The fun in any negotiation is the small-print. In what ways could mighty Elsevier have screwed over tiny VSNU (the combined Dutch universities) or the other way round? One bottleneck could be the phrase "Dutch researcher". Researchers tend to publish their work in an international collaboration, a sort of behaviour encouraged by the Dutch money donors. Do only 100% Dutch science-crews apply for free open-access publishing?

More damaging for the VSNU is the stipulation that Elsevier is to select a list of publications available for free open-access. If a desired publication is not on the list, the researcher will still have to pay up to 1500 euro's to see it published. So what is keeping Elsevier from introducing a really shitty open-access publication such as "The Journal Of Really Shitty Open-Access Publications"?

Final unknown: to what extent is the publication open-access? You would naturally expect: open-access free-for-all but you are jumping to conclusions and you are a bit naive: it could of course mean that the semi-open-access publication is only accessible via a university library login and not to the common man. Not an agreement then, more like a truce?