Are natural products isolated from plants, products of epi- and/or endo-phytic microbial interactions with/within the host?

Over the last 15 or so years, there have been multiple reports that "plant-derived" molecules such as paclitaxel, camptothecin, vinca alkaloids, hypericin etc., have been purified from fermented microbes (usually fungal isolates) that were endophytes of the "producing plant". We will discuss these and other reports of the production of molecules as disparate as maytansine and kampferol by microbes isolated from the "producing-plant species". It is tempting to suggest that at this time, we might be at a period in the study of plant metabolites comparable to the one that occurred in the late 1980 s with marine invertebrates, when compounds isolated from marine sponges were shown to have structures very similar to those isolated from terrestrial microbes. This work led to the current recognition that a majority of marine invertebrate metabolites are in fact produced by associated microbes, even though in a number of cases, these microbes have not yet been cultivated. Is this now the case with "some" plant-derived compounds?