Thanks for the paper Xabier!
On 15 December 2015 00:45:07 GMT+00:00, "Xabier Vázquez Campos" <xvazquezc@gmail.com> wrote:
Sebastian, Gelrite (gellan gum) needs divalent cations to gel in normal conditions. I've use it for culturing fungi even at pH 1.0. Although the concentration needed may vary. Most media contain absurdly high phosphate concentrations and some studies have shown that many, if not most, bugs can grow even better with much lower levels or even just traces of phosphates in the media
Cathal, the ROS generation in agar autoclaving seems to be linked to autoclaving the agar with all other media components, especially the phosphates. Check this paperTanaka, T., Kawasaki, K., Daimon, S., Kitagawa, W., Yamamoto, K., Tamaki, H., Tanaka, M., Nakatsu, C. H. & Kamagata, Y. (2014). A hidden pitfall in the preparation of agar media undermines microorganism cultivability. Appl Environ Microbiol 80, 7659–7666.
On Friday, 11 December 2015 08:06:35 UTC+11, Sebastian wrote:Gelrite (gelzan) is nice for its clarity. A little soft and more expensive than agar agar. It is also fairly sensitive to pH and is basically slush around 5.0-5.3 (I learned that the hard way). It also doesn't like high phosphates like that in M9. Its good in some cases for plant tissue culture, bad for pretty much everything else. There was this pallet sold on eBay for $80/kg of gelrite and I gobbled up four tubs. Street price is like $160 and now this little publicity stunt will most likely artificially drive prices up before any real shortage occurs.You could use any agar if you just test for gel strength. I made a little jig a while back to measure gel strength relative to 1000g/cm3 agar using a rubber band, pen, and some popsicle sticks. It just measures how high a pen attached perpendicularly to a flat 1cm^2 can rise on a scale when force from rubber band acts on it. Basically force till smush. Calibrate it with a weight for analytical balance calibration and derive force. You can also use muscle memory if you culture a lot and know when its right. I can tell if I messed up the pH in my MS based on the jiggle in the media bottle and the way the seeds embed when dropped. I know thats not very scientific but agar varies so much batch to batch and strain to strain (algal species like carigeean) that sometimes you need a more instinctive understanding. This of course is not too necessary for routine bacteria. If you flick an upside down plate and it vibrates a bit, its dense enough. For plants its a whole different story. Density impacts root formation greatly and some just wont root in soft or too hard agar. Interesting things you learn when you do this for too long...
Sebastian S. CociobaCEO & FounderNew York Botanics, LLCBlog: ATinyGreenCell.comTime to stock up and re-sell for a profit.I've heard GelRight is a good alternative. Supposedly, it's even more "inert" than agar.--On Thu, Dec 10, 2015 at 12:46 PM, Yuriy <yuriy...@gmail.com> wrote:Time to look for alternatives.--
On Thursday, December 10, 2015 at 9:49:46 AM UTC-5, Koeng wrote:
-- You received this message because you are subscribed to the Google Groups DIYbio group. To post to this group, send email to diy...@googlegroups.com. To unsubscribe from this group, send email to diybio+un...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/ forum/diybio?hl=en
Learn more at www.diybio.org
---
You received this message because you are subscribed to the Google Groups "DIYbio" group.
To unsubscribe from this group and stop receiving emails from it, send an email to diybio+un...@googlegroups.com.
To post to this group, send email to diy...@googlegroups.com.
Visit this group at http://groups.google.com/group/diybio.
To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/8c686df0-04bf- 41f3-8286-6d290d723889% 40googlegroups.com.
-- You received this message because you are subscribed to the Google Groups DIYbio group. To post to this group, send email to diy...@googlegroups.com. To unsubscribe from this group, send email to diybio+un...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/ forum/diybio?hl=en
Learn more at www.diybio.org
---
You received this message because you are subscribed to the Google Groups "DIYbio" group.
To unsubscribe from this group and stop receiving emails from it, send an email to diybio+un...@googlegroups.com.
To post to this group, send email to diy...@googlegroups.com.
Visit this group at http://groups.google.com/group/diybio.
To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/ CAGdeWmRCjXyAibSzpqpZ9PM- REMktZFEJQxCs2fpH7xry8MWig% 40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
0 comments:
Post a Comment