Bacterial smells, odorants

EDIT: This article proves to be very popular, I will append it in the future.

  1. streptococcus milleri — browned butter
  2. pseudomonas aeruginosa — flowery, sickly sweet, “concord grapes”, naphtalene-like, grape candy
  3. clostridium difficile — horse excrement, heinous smell
  4. proteus sp. — sweet, corn tortilla smell, ‘masculine notes’
  5. actinomyces sp. — wet earth smell after rain
  6. flavobacterium odoratum, alcaligenes faecalis — ‘fruity’
  7. alcaligenes odorans — ‘fresh cut apple’
  8. streptomyces — ‘dirt cellar’
  9. cyanobacteria, actinomyces — geosmin, ‘potting soil’
  10. source
  11. streptococcus pneumoniae — methyl methacrylate up to 1420 ppb! (Methyl methacrylate, that is what is used to manufacture acrylic plexiglass, also used in dentistry, you absolutely should know this chemical! Basically, if you smell this on the lung breath (among other things), act fast, direct your ‘hits’.)
  12. staph sp., corynebacterium sp. and 100 others — sulphur odours
  13. choline metabolism –> trimethylamine
  14. dimethyl disulfide, sludge –> lactobacillus, corynebacterium, pseudomonas acidovorans, pseudomonas alcaligenes, preudomonas pseudoalcaligenes, pseudomonas testosteroni, Alcaligenes denitrificans subsp. xylosoxydans, Alcaligenes denitrificans subsp. denitrificans, Alcaligenes faecalis, Alcaligenes odorans, Achromobacter group Vd, source
  15. dimethyl sulfide, nature –> Pseudomonas spp., Streptomyces, Bacterium spp., Aspergillus spp., Clostridium sporogenes, Alteromonas putrefaciens, Pseudomonas fluorescens, Achromobacter spp., Pseudomonas putida, Proteus spp., Pseudomonas fluorescens, Proteus vulgaris, Serratia marcescens, source

“Anaerobes are particularly pungent due to their reliance on sulfhydryl compounds to maintain redox balance.”

grape, sweet aroma: 2-Aminoacetophenone

NOTE HERE: notice that sickly sweet-ish aromas may be also products of not only purely bacterial “fermentation” (in the generic sense of the word), but also a combination of human pheromones, scent glands (oiling glands on specific body locations), the mentioned microbially processed aforementioned excretions, or these may be even pure, unaltered scents. (Remember how sweetly baby heads smell? Those are hormones/pheromones and fatty acids in action, the smell itself can alter human emotions/actions, so we can argue humans do have a pheromone/scent gland system, even if it is marginal.)

16. butyric acid and butyrates… you know this smell all too well. Easily located in dental plaques, it is many times the product of fusobacterium nucleatum, you better learn to recognize this smell quickly, it is very unique smell, even if not unique to this bacteria. The butyric acid is an irritant and among other bacterial products helps to damage cell walls (bleeding, shriveled gums, anyone?). Fusobacterium nucleatum is a “bridge” bacteria, it provides the biofilm framework on which plethora of others, even pretty dangerous ones will operate. Don’t bother throwing antibiotics at it, this bacteria works differently; as it consumes proteins for all its energy needs, protease inhibitors will lead to cell death. I heard that Bestatin might be very efficient. As this bacteria is not motile, very conscientious physical clean-up of plaques, followed by surface sterilisation (like very weak solution of AgNO3), may trigger rapid wound healing, as this bacteria stops *forgot the name of the progenitor cells that facilitate healing” from working. Also some tumors need this bacteria to operate, so eradicating in on the spot may make the tumour to die away on its own. Link: Bacteria and tumours: causative agents or opportunistic inhabitants?

17: propionic acid: I do not have separate info right now, so assume the above is valid as well, when these acids are present in significant quantities, assume that bacteria able to permanently colonize mouth is present.

Leave comments, pls.



Flydubai FZ981

Boeing 737-800, similar case as the Air Malaysia lost over the Indian ocean, and even the Lufthansa A320 depressed pilot. Air Malaysia had two pilots, old one, tired and possibly depressed (see the video of them going trough checks, he had a lack-of-sleep hangover or something like that) and young one, who looked okay.

THE THEORY. There is something in the airplanes themselves that affects the psychological state of the pilots. We already know these in the list:

  1. changing time zones, long hours , irregular sleep, demanding lifestyle
  2. long periods of decreased air/oxygen pressure
  3. fumes from the APU(such as), fumes from the electronics, carpets
  4. electrolyte balance, saltiness taste changes at lower air pressure

The third one is still the most acute of the three, and as the fumes contain mainly nerve poisons, it needs to be seriously evaluated as an occupational hazard and safety hazard.

Altered state of thinking: lack of sleep and lowered air pressure alone are enough to alter perception and judgement. People ask: “why were they circling for 2 hours and not diverting?” Let me tell you that when your immune system, energy and oxygen delivery into brain snaps, sitting 2 hours doing nothing and waiting will fly past as if it were 15 minutes. Been there. The Air France that crashed in the Atlantic after slowly losing altitude over long period of time is another example. Record shows them reacting slowly, confusedly, during a night and after a good dinner.

The Flydubai FZ981 plane went down in a very steep dive. In the hours before that, their conversations with the tower were trivial, almost as preschoolers.

What I think additionally needs to be done is to prepare meals suitable for high altitude consumation, vitamins promoting neuroprotection and proper neurological function (about 5 or 6 B-vitamins and such), and medication improving the use of oxygen, nutrients from time to time. (Mildronate from the Sharapova fiasco, or substances from the same “Actoprotector” class.)

And the whole concept of air supply and filtering into airplanes needs to be rethought. Possibly oxygen enrichment, even. (25% oxygen) These tragedies are 100% preventable in the design and preparation phase. Commercial airlines lack the physical, nutritional and mission preparation typical for  U-2 pilots. Such procedures would decrease tragic accidents, but would be hard to implement, even partially.

EDIT: As is shown time and time again, rest for the pilots needs to be provided. If you really make them work in 14-16 hour stretches, give them the ability to roam on the plane and sleep there in shifts as well. That was one of the perks in the 1950’s and 1960’s, pilots left and returned to the cockpit as they pleased. It would be easier if you employed 3 pilots instead of 2, but that is no company willing to do. I wonder why.