Castor seed has abundant level of proteins which are evolved spontaneously to serve the survival demands of the organism in response to the selection pressures. Among multiplicity in proteins, scientists have started focussing on three candidate proteins 2S namely albumins,Ric c1 and Ric c3 which have been earlier characterized as allergens for their biological significance.In general, bio-molecular functional definition can be arrived from analysis of its constituents and its spatial configuration that stood as bases for the functional implications in chosen castor proteins.The allergen proteins under study are found to contain a domain for digestive enzyme inhibition which made researchers to design an insect feeding bio-assay in insects Callosobruchus maculatus, Zabrotes subfasciatus, and Tenebrio molitor over their most optimal diet with parameters of insect larvae mortality and body mass gain from diet containing castor protein allergens .The results confirmed that a loss of body weight by one-fifth fraction compared to control lines which enabled researchers to arrive at the enzyme inhibitory activity from concerned plant proteins due to test domain in them.Further scientists claimed that the castor proteins are potential targets in the design of inhibitors with importance in crop protection and biomedical field.
The results seem to be promising for the feeding deterrent activity from castor proteins but it would be convincing if an in vitro enzyme assay with gut enzymes against castor allergens and histopathological analysis of insect tissues for molecular complexes would have been performed for confirmed functional implication.
For further info: http://pubs.acs.org/doi/abs/10.1021/jf104638b
Some interesting links
Castor oil is readily available here in the US and you can find it in most health food stores. Based on what you say about allergens and toxins, how safe is it for personal skin care use? Or are you referring to a lower grade castor oil?
Respected Sir/Madam
Allergens and toxins are confined to castor cake selectively that is left as debris after the extraction of oil from castor seed. So, oil is generally devoid of toxins and allergens and rendering it as an elixir whether taken by oral or parenteral administrations at prescribed limits.
I do not refer to grade of castor oil as it is not a serious concern with respect to its therapeutic properties.