This has been a pretty hectic week, and with lots of food for thought. The situation in the world concerns me, and also other issues of the bigger picture. But today I will focus on updates on bugs. Taking care of microbes growing has  a zen-like quality to it. Call me old-fashioned, but waiting for a hot loop to cool is relaxing.

One of the bugs I brought from Yale, a perky Pseudomonas, has proved to be a funky one. Last week I strode into the lab and decided to try everything available in the fridge, and inoculated all kinds of media to get more information. Results came out along the expected ways (negative fermentation and MR-VP among others), but the nitrate was negative. The sequence had been pointing at a weird fish-killing Pseudomonas, but  P.plecoglossicida is nitrate positive. My bug did not seem to be fluorescent under UV light, so P. fluorescens seemed to be out of question, but it is nitrate negative, so I inoculated a couple of gelatin deeps and am waiting for the results, gelatinase production being one of the distinguishing features. I have been around labs enough to not get too excited about weird stuff, and I just cannot believe that the soil at Yale University is harboring some kind of special bug. But at the end that is not so important…it is the antibiotic production that matters. So I am also repeating the spread/patch plate against four bugs, including E. coli & P. aeruginosa. After that, if things repeat, then I will have to make some decisions about what to do next.

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West Coast & East Coast kombucha. Just refilled the East Coast one, that’s why it is in the bottom.

As for kombucha, as they say, no news is good news. It has been growing placidly in the corner, by now in its 3rd of 4th tapping. The first ones had 1/2 cup of sugar per liter, and were very sweet in the beginning and very tart at the end. Then I halved the sugar amount, and the resulting drink was way mellower but also bland. I had started experimenting with diluting the strong concoction with fruit juices, which seems to produce a pleasant flavor. Another option is to add chia seeds, which give a nice chewy quality to the drink not to mention the added protein. I finally relented and bought a set of big jars for the cultures. The West Coast one has been steadily growing, and I can see it becoming equal to the Yale one, especially after today as I started to give away babies (tearing away a layer). Next stage will be experimenting with different teas and sources of sugars.

My next post will be about scaffolding assignments for a General Bio class. I had a kind of epiphany about grading rubrics the other day while banging my head in frustration because of students not following instructions. Stay tuned!

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