MicrobeHunter.com Microscopy Forum

Hi all, thought you may like to see a few images I took the other day, rather 'unplanned' as they were, they're also of pretty poor quality, apologies.....

I was literally just about to chomp a tasty-looking scone made several days before by my dear Wife when I thought I saw a faint 'whiteness' about the surface - almost invisible but hey, for a fellow with a stereo 'scope handy - no problem to check this out!

Anyway, I scraped a tiny bit of the surface of said scone and smeared the scrapings onto a slide and stained lightly with lactophenol cotton blue stain, as I suspected fungus! I think I was right!
I've no idea what fungus it is, and the images are so poor that I'm unlikely to be able to find out....

These look like bunches of whatever a fungus has for 'flowers'?
Again sorry for the poor images,
and, I also had a peek with polarisation to extinction - nothing with the fungus, but the starch from the scone is clearly visible in 'blobs' of different sizes - Maltese crosses everywhere! Interesting! Oh yes, I decided on some Doritos instead of the scone for a snack.....

John B.

Yes. Now I carry around a stereoscope to examine all my snacks prior to consuming them..

Nice shots! Very colorful too.

Haha! Thanks einman old chap!

John B.

einman wrote:Yes. Now I carry around a stereoscope to examine all my snacks prior to consuming them..

I'm sure this will provide lively experiences especially when discussing your stained findings with you table neighbours in a better restaurant!

@ John B: Does lactophenol cotton blue stain just stain everything or does it differentiate between different tissues?

Bob

These look like bunches of whatever a fungus has for 'flowers'?

If my memory serves me they're conidiophores bearing conidia, or asexual, wind-borne spores, produced by mitosis so no, they're not analogous to a flower as they are purely a means of asexual propagation, in terms of the Plant Kingdom (an obsolete analogy -- the Fungi are opisthokonts and actually nearer animals than plants, they stand in their own kingdom) a prolongation of the current generation, rather than an elaborate structure that gives rise to the next stage in the antithetic alteration of generations by meiosis.

SutherlandDesmids wrote:

These look like bunches of whatever a fungus has for 'flowers'?

If my memory serves me they're conidiophores bearing conidia, or asexual, wind-borne spores, produced by mitosis so no, they're not analogous to a flower as they are purely a means of asexual propagation, in terms of the Plant Kingdom (an obsolete analogy -- the Fungi are opisthokonts and actually nearer animals than plants, they stand in their own kingdom) a prolongation of the current generation, rather than an elaborate structure that gives rise to the next stage in the antithetic alteration of generations by meiosis.

Very true old chap, I've sent you a pm re 'scopes.

John B.

MicroBob wrote:

einman wrote:Yes. Now I carry around a stereoscope to examine all my snacks prior to consuming them..

I'm sure this will provide lively experiences especially when discussing your stained findings with you table neighbours in a better restaurant!

@ John B: Does lactophenol cotton blue stain just stain everything or does it differentiate between different tissues?

Bob

Hi Bob!

Lactophenol is one of the go-to stains for fungi I believe and is particularly good at differentiating fungi. The aspect of differentiation with stains is though by no means as simple as that. For a stain to differentiate and stain selectively many factors come into play, concentration, solvent used (e.g. water, OH, oil....), other stains also present, order of application of stains, pH of tissue or stain solvent, the list is endless. Its not easy at all to add a stain to a tissue and achieve totally selective staining, more a balancing act of many interacting factors. But, for fungi Lactophenol will give a nice strong result, and a high contrast is an absolute must for photography through a 'scope I've found - the long way around...

It would have been just as well to have used say Safranin, or alcian-blue or methylene-blue come to that. I made some very nice differentiations for some slides of fungal-infected Sonchus.arvensis leaves by using safranin to stain the fungus involved....

Here's a safranin-only fungal stain, the fungus is within the tissue of the Sonchus.arvensis leaf, Here's a version using alcian-blue for non-fungal cells and safranin again for the fungus, This version is a triple-stain using alcian-blue again for the non-fungal leaf tissue and two stains for the fungal tissue, orange-g to pick-out the 'stalk' or 'stipe' and safranin to stain the conidium (I think these terms are correct, but I know very little about fungus). Here's a section of the leaf used, unstained of course, as seen under my stereo 'scope before subsequent processing, sectioning and staining, Again 'raw' - from above the chamber containing the fungal structures seen above is seen to have a surrounding of finger-like paraphyses and the conidia that they protect..... Fungi may be stained with many stains, Toluidine blue is another water-borne stain that is great fro living tissue and will also give differentiation via metachromasia (it stains different colours for different tissue components) on it's own - easy to buy too - a great first stain for fresh un-treated staining.

I really need to learn a bit more re the names of the parts, I've had a go at labelling but still not sure....

John B.

beautiful

Hi John B.,

I think you did your usual first-class job here.....

BillT

Doesn't all bread have yeast all over it? I've never had a scone; not sure exactly what it is, but it sounds rather bread-like...

Hi John,
thank you for the explanation redarding the staining process. I will give this a try sooner or later.

Bob

That is a species of Penicillium. Personally, I prefer fuchsine in lactic acid. No phenol, the lactic acid is a fixative and thick enough to take days to dry out, and has a different RI than the stained fungal tissues further enhancing contrast.

mnmyco

wow - no idea about the technical aspects or biology of it, but the images are certainly pretty.
I had no clue that fungus was so attractive up close. Lovely shots.

wstenberg wrote:Doesn't all bread have yeast all over it? I've never had a scone; not sure exactly what it is, but it sounds rather bread-like...

Yeast will look like large bacteria, and will not survive the cooking process. Also, not all bread has yeast.

mnmyco