Wednesday, 28 January 2009

Peanut contamination - bird tragedy averted

Lincolnshire bird numbers could have been decimated by 100 tons of carcinogenic peanuts seized by Trading Standards officers.

The peanut mountain was discovered in a warehouse in the county and contained enough highly toxic fungus to kill hundreds of thousands of wild birds.
Fortunately the nuts were seized by Trading Standards officers and tragedy averted.

Gary Seymour, assistant head of Trading Standards, said: "In this case there were about 100 tons of peanuts involved and our controls cover the safety of both birds and humans – as adults and children may think they were safe to eat them."

Professor Geoff Turner, an expert in fungal genetics from the University of Sheffield, who works with the aspergillus fungi that produces lethal aflatoxins, described the dangers.

"Peanuts are famous for aflatoxins and there's always a risk when they come from countries where the food checks aren't so good," he said."There are two things they do. At a high enough level they can kill an animal straight away, but it's also one of the most carcinogenic substances ever known."

The peanuts have now been exported to Holland for decontamination and Trading Standards are taking no further action.
This story was reported in the Lincolnshire Echo. For more on the averted bird holocaust, see Wednesday's Echo.

Tuesday, 27 January 2009

Aspergillus as a Probiotic for animals?

Probiotics are used as food supplements and are broadly defined as: "Live microorganisms which when administered in adequate amounts confer a health benefit on the host"

There are an increasing number of reviews and research papers on the use of Aspergillus as a probiotic in farm animal feed. It is recorded as having beneficial effects on - nutrition uptake (e.g. making nitrogen more available in ruminants), blood cholesterol levels, mineral absorption and adjusting the gut microflora. The overall purpose of feeding animals a probiotic is to increase food production, the measurement of which is feasible and achievable through measurement of food output i.e. meat weight, egg production numbers and so on.

When it comes to non-food producing animals i.e. domestic pets, the use of these products is less obvious and less measurable. These products are sold to 'make our pets healthier' in some way and also to make food more palatable - but this is not a measurable commodity for the pet-owner and there is often very little, well conducted research to support the claims. In short there is a large dose of marketing involved and much less evidence to suggest it is worth paying out sums of money for these supplements.

Monday, 19 January 2009

Coral destruction by Aspergillus

For some years now Aspergillus has been infecting and in some cases killing the sea fans (Gorgonia ventalina) off the Caribbean coast.
The image on the left shows an infection that began at a single point of infection and which has gradually expanded outwards.
The frond is a light purple colour where it is healthy but takes on a much darker hue of purple around the infection, and this indicates where the coral is dying (see link for more details) whereas the green central area is dead coral.

This Youtube movie shows the researchers examining the damaged corals, narrating as they go. There is a second part of this movie here.

Corals are thought to be similar to ourselves in that they can resist infections as long as they are healthy, so why are these corals becoming infected?

  1. Garrison et.el. suggest that the mould is blown over from Saharan Africa, suggesting that the Carribean reefs are bening overwhelmed by the fungi carried by this dust. My feeling is that this might provide a source for the infection but there must be more to it than this - Aspergillus is found everywhere regardless of dust storms. Garrison et al. 2003. African and Asian dust: from desert soils to coral reefs. BioScience 53: 469-481.
  2. Global warming. We know the seas are getting warmer and this may well contribute to making the coral more susceptible to infection.
  3. More recent research has shown nutrient enrichment can increase coral disease. Infection by Aspergillus is noticeably patchy throughout the Carribean so it could be that nutrient rich pollutants are present in those areas. Bruno et al. 2003. Nutrient enrichment can increase the severity of coral diseases. Ecology Letters 6: 1056-1061.
We must conclude that there could be a variety of reasons for the large scale die-off of corals in the Caribbean. It is not only sea warming - otherwise why would disease be worse in some areas? Pollutants may also have a major effect.
This shows why we must always not accept the first, most obvious cause for a problem without question, there is often an underlying less obvious contributor to the situation.

Tuesday, 13 January 2009

Cell wall component of Aspergillus niger has good moisturising properties and is eco friendly

A Belgium-based company KitoZyme has performed a number of trials investigating the potential of its chitin-glucan ingredient in skin care products. Chitin-glucan is a copolymer found in the cell wall of several fungi, including Aspergillus niger, the source of KitoZyme’s ingredient.

In a 16-week study, a moisturizing day cream containing 1.5% chitin-glucan was applied twice daily to two 3cm areas on the forearm of 20 healthy men. A similar moisturising cream without the chitin-glucan was applied to the other forearm to act as a control.

Skin firmness, stratum corneum hydration and skin topography were measured as was skin surface harshness and skin roughness. Skin firmness was measured by investigating the propogation speed of an ultrasound shear wave and, according to the results, treatment with chitin-glucan significantly firmed the skin compared to the placebo, particularly at the end of the treatment. The electrical capacitance of the skin was used to measure the skin hydration and the study claims the chitin-glucan improved skin hydration by 11.3% from week 4. Measurements of skin topography also improved after the application of chitin-glucan, the study claims.

The study concludes that the ingredient has potential for use in skin-moisturizing and anti-aging formulations. In addition, it highlights the non animal-derived and environmentally friendly nature of the product particularly as KitoZyme’s chitin-glucan ingredient is extracted from the vegetative part (mycelium) of a microscopic fungi Aspergillus niger, which is already a by-product of the commercial production of pharmaceutical and food-grade citric acid.
Full report

Monday, 5 January 2009

Antifungals for the Treatment of Asthma

Many asthma sufferers are known to the sensitised to fungi - a condition known as Severe Asthma with Fungal Sensitisation (SAFS). A similar series of studies on the more severe form of asthma known as Allergic Bronchopulmonary Aspergillosis (ABPA) has shown a beneficial effect of treatment with antifungals.

ABPA patients are known to have Aspergillus growing in their lungs so it is logical that antifungal medication will ease the infection - though it is very unusual that the antifungal would be able to eradicate the infection completely. ABPA is treated long term with steroids to control the inflammation caused by the fungus. Long term use of steroids can be very unpleasant as there are many potential side-effects. Treatment with antifungals lessens the symptoms and therefore allows a reduction in the use of steroids, bringing about a reduction in unpleasant side effects.

Of course antifungals such as itraconazole can also have side effects so close monitoring is required in the initial stages of treatment.

SAFS patients are not known to have fungi growing in their lungs and have much lower detected fungal contact as measured by IgE, so it is not as clear whether or not treatment with an antifungal drug would help ease the asthma symptoms.

Denning et al. sets out to assess whether patients with SAFS respond to treatment with an antifungal drug. Patients with sensitivity to at least one of a panel of seven fungi were recruited, but those with very high IgE were rejected so to exclude ABPA. Treatment with itraconazole for up to 32 weeks gave a significant improvement in quality of life and reduced IgE score.

Antifungal use to treat this group of patients does therefore have some evidence to support it as a viable treatment option, and hints at direct fungal involvment in some severe asthma.
Manchester University link

Contact us at