Saccharomyces cerevisiae, lysate

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods, other

Type of information:

other: Publication

Adequacy of study:

weight of evidence

Study period:

2005

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline required

Principles of method if other than guideline:

Aerobic and anaerobic bacterial counts, as well as fungal counts of viable microorganisms in soils and gut sections, were made on twenty L. violaceous collected from different sites on the campus of the University of Agriculture, Abeokuta, Nigeria.

GLP compliance:

not specified

Test organisms (species):

other: Libyodrillus violaceous (Annelida: Oligochaeta)

Dose descriptor:

other: not applicable

Effect conc.:

0 other: not applicable

Conc. based on:

other: not applicable

Basis for effect:

other: not applicable

Remarks on result:

other: not applicable

Conclusions:

Saccharomyces spp was detected in all sampling sites, in un-ingested soil, fresh cast, two weeks old
cast, and in the fore gut, mid gut and hind gut and gut contents of earthworms and thus represents
one of the yeast genus with the largest distribution.

Executive summary:

Earthworms are soil invertebrates that play a key role in recycling organic matter in soils. In Nigeria, earthworms include Libyodrillus violaceous. Aerobic and anaerobic bacterial counts, as well as fungal counts of viable microorganisms in soils and gut sections, were made on twenty L. violaceous collected from different sites on the campus of the University of Agriculture, Abeokuta, Nigeria. The samples were collected between April and November, 2002. Numbers of microorganisms were higher in castings and gut sections than in uningested soil samples. The guts and their contents also had higher moisture and total nitrogen contents than the un-ingested soils. Bacteria and fungi isolated from the samples were identified by standard microbiological procedures on the bases of their morphological and biochemical characteristics. Isolated bacteria were identified as Staphylococcus, Bacillus spp., Pseudomonas aeruginosa, Streptococcus mutans, Clostridium, Spirocheata spp., Azotobacter spp., Micrococcus lylae, Acinetobacter spp., Halobacterium for bacteria. Yeast isolates were identified as Candida spp., Zygosaccharomyces spp., Pichia spp., and Saccharomyces spp while molds were identified as, Aspergillus spp., Pytium spp., Penicillium spp., Fusarium spp and Rhizopus spp. Of the five locations examined, the refuse dump area had the highest numbers of both aerobic and anaerobic organisms, followed by the arboretum while the cultivated land area recorded the lowest counts. The higher numbers of microorganisms observed in the gut sections and casts of the earthworms examined in this work reinforce the general concept that the gut and casts of earthworms show higher microbial diversity and activity than the surrounding soil.

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods, other

Type of information:

other: Publication

Adequacy of study:

weight of evidence

Study period:

2013

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline required

Principles of method if other than guideline:

Not applicable

GLP compliance:

not specified

Test organisms (species):

other: Panagrolaimus sp.

Animal group:

nematods

Key result

Dose descriptor:

other: Not applicable

Effect conc.:

other: Not applicable

Basis for effect:

not specified

Remarks:

Not applicable

Remarks on result:

other: Not applicable

Validity criteria fulfilled:

not applicable

Conclusions:

Using yeast Saccharomyces cerevisiae as feed in nematode cultures increase the yield without causing any toxicity.

Executive summary:

The free-living nematode Panagrolaimus sp. (strain NFS-24-5) has potential to be used as live food for early stages of marine aquaculture fish and shrimps. One prerequisite for commercial application is the mass production at low costs. The objective of this study was to test whether fed-batch conditions can increase nematode yields of monoxenic liquid cultures with cells of the yeast Saccharomyces cerevisiae in flasks and bioreactors. Liquid cultures in flasks observed over 16 days provided contradicting results. In lab-scale bioreactors significantly lower nematode yields were obtained under fed-batch conditions. Maximum nematode density reached in a bioreactor process under batch conditions was 270 × 103 nematodes ml-1 and in fed-batch at 153 × 103 nematodes ml-1. In flasks nematodes had a lag phase of 8 days until reproduction started. This period was reduced to 4 days by culturing in bioreactors.

Reference 3

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

other: Risk assessment

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline required

Principles of method if other than guideline:

Not applicable

GLP compliance:

not specified

Key result

Dose descriptor:

other: Not applicable

Effect conc.:

0 other: Not applicable

Conc. based on:

other: Not applicable

Basis for effect:

other: Not applicable

Remarks on result:

other: Review. Quantitative result was not determined.

Conclusions:

Yeast Saccharomyces cerevisiae is ubiquitous in nature and naturally occuring in all environmental compartments and animals. soil organisms are continuously and naturally exposed to Saccharomyces cerevisiae. No toxicity of yeast and yeast extract is expected in all environmental comparments.

Executive summary:

Yeast Saccharomyces cerevisiae is ubiquitous in nature and naturally occuring in all environmental compartments and animals. soil organisms are continuously and naturally exposed to Saccharomyces cerevisiae. No toxicity of yeast and yeast extract is expected in all environmental comparments.

Reference 4

Endpoint:

toxicity to soil macroorganisms except arthropods, other

Type of information:

other: Review

Adequacy of study:

weight of evidence

Study period:

2015

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline required

Principles of method if other than guideline:

Not applicable

GLP compliance:

not specified

Key result

Dose descriptor:

other: not applicable

Nominal / measured:

not specified

Basis for effect:

not specified

Remarks on result:

other: Peer review of the pesticide risk assessment of the active substance Saccharomyces cerevisiae strain LAS02

Conclusions:

Yeast Saccharomyces cerevisiae is ubiquitous in nature and naturally occurring in all environmental compartments and animals. No toxicity of yeast or yeast extract is expected in all environmental compartments.

Executive summary:

The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State France for the pesticide active substance Saccharomyces cerevisiae strain LAS02 and the assessment of the application to include Saccharomyces cerevisiae strain LAS02 in Annex IV of Regulation (EC) No 396/2005, are reported. The context of the peer review was that required by Regulation (EC) No 1107/2009 of the European Parliament and of the Council. The conclusions were reached on the basis of the evaluation of the representative use of Saccharomyces cerevisiae strain LAS02 as a fungicide on pome fruits, stone fruits, grapevine, tomato and strawberries. The reliable endpoints, appropriate for use in regulatory risk assessment are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

Additional information

Saccharomyces cerevisiae which is present worldwide, has been recovered from a variety of sites under varying ecological conditions. Saccharomyces cerevisiae has an extensive history of use in the area of food processing and is used in a variety of industrial scenarios (EFSA,2015). Saccharomyces cerevisiae is ubiquitous in nature and naturally occurring in soil and animals. The presence of living yeast in soil compartments implies the presence of dead yeast which composition can be compared to yeast extract. No toxicity of yeast and yeast extract is expected in all terrestrial compartments. Moreover, the macrocomposition of yeast extract, consisting of proteins, carbohydrates and salt, corresponds to elements composing all organisms. No toxicity of these elements is expected on environmental compartments (US EPA,1997)
Idowu et al. (2006) examined the microflora of soil, earthworm casts and earthworm guts. Along with Candida spp., Zygosaccharomyces spp. and Pichia spp., Saccharomyces spp. have been isolated from all of the samples. It is assumed that microorganisms including yeasts, ingested by the earthworm together with litter, help the earthworms to breakdown the organic matter, particularly the components which are not digestible by the earthworms in their natural stage. Therefore, yeasts contribute to the earthworm’s nutrition in a symbiotic way.
Honenns and Ehlers (2013) showed that Saccharomyces cerevisiae can be used as feed in nematode cultures and can increase the yield without causing any toxicity.

Soil organisms are continuously and naturally exposed to Saccharomyces cerevisiae therefore no toxicity of Saccharomyces cerevisae or derivatives (yeast, yeast extracts and yeast cell wall fractions) is expected on terrestrial compartments.
Due to the general absence of toxicity of Saccharomyces spp. to earthworms and considering their ubiquitous occurrence in the earthworm’s habitat, no adverse effects are expected upon soil application of "Saccharomyces cerevisiae, lysate/EC 305-230-8" . Studies on earthworm toxicity are considered not required.