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The natural product ambergris is only found rarely on beaches, as jetsam. Even more scarce, or even absent, are accounts of flotsam ambergris. Here, we report the chemical analysis of a rare, large piece (>100kg) of flotsam found in the Atlantic in 2019. About 95% of subsamples from the outside of the coprolith was soluble in dichloromethane. Of this, FTIR spectroscopy, APCI-MS and GC-MS indicated the presence of ambrein. Radiocarbon dating indicated that the sample was post 1950s in age. The 13 C/ 12 C isotope ratio (-22.5 ‰) was typical of those reported to date for whale 'body' ambergris. Metals of ambergris have hardly been reported previously. The distribution found here for the flotsam, was dominated by copper and zinc, which is similar to that of several squid species. This is also consistent with the presence of squid beaks in the coprolith. Squid are a major prey species of sperm whales.

The use of atmospheric pressure chemical ionisation (APCI) compact mass spectrometry (CMS) was investigated for the analysis of jetsam and museum-archived ambergris and of ambergris components in perfumes. The data were compared with those from existing methods. Authentic samples of some individual ambergris constituents (ambrein, coprostanol, epicoprostanol and coprostanone), were also examined. Rapid APCI CMS was achieved using either a solids probe or a probe with solutions held in capillary melting point tubes. Interpretation is made of the spectra of the principal natural product components, the relative ion responses were measured and the elemental composition of key ions in the spectra confirmed using high resolution accurate mass APCI MS. Rapid analysis of ambergris by APCI CMS may prove to be a further convenient method of identifying ambrein, of measuring the relative ratios of ambrein and steroids in ambergris and even of quantifying the latter, with minimal sample preparation.

For nearly 200 years, the only natural source of the alcohol ambrein has been coproliths produced in about 1% of sperm whales and in related jetsam. However, the finding of ambrein in adipocere/faeces of human corpses, led us to hypothesise that ambrein might occur in the faeces of other mammals. Herein, we used a recently developed gas chromatography-mass spectrometry method, with suitable derivatisation of the hindered hydroxy group of ambrein, to screen a number of extracts of mammalian faeces. Minor proportions of ambrein were detected in digested human sewage sludge and in the dung of elephant, domestic cattle, giraffe and buffalo. Whether ambrein formation in the terrestrial species is associated with coprolith formation, is unknown, but solid deposits known as enteroliths and fecaliths occur in humans and some domestic animals.

Ambrein is found in ambergris, a coprolith occurring in the rectum of the sperm whale. In vitro , ambrein is produced by enzymatic cyclisation of squalene, via a monocyclic intermediate. However, little is known of the in vivo process. In order to find evidence for the reaction in vivo , a comparison was made of the δ 13 C relative isotopic ratios of ambrein in ambergris with those of co-occurring sterols. A statistically significant difference was noted. This suggests that ambrein originates via a different biosynthetic mechanism from that of the sterols. Examination of the minor constituents of a hydrogenolysed extract of ambergris revealed compounds with a bicyclic polypodane nucleus, rather than those with monocyclic structures. It is hypothesised that in vivo biosynthesis of ambrein proceeds, at least in some cases, via bacterial production of bicyclic polypodenols. The latter are known products of non-concerted squalene (or squalene oxide) cyclisations in other organisms.

Volatile and semi-volatile compounds account for the odors, long valued in the perfumery industry, of the natural product, ambergris. Here we demonstrate application of solid phase micro extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) to headspace analysis of the volatiles and semi-volatiles of jetsam ambergris. The samples collected in 2017/2018, ranged from a black, sticky material from New Zealand, likely recently ejected from a sperm whale, to a white solid found on a beach in Chile and radiocarbon-dated previously to be about 1000 years old. The traces of volatile/semi-volatile compounds extracted included, odorous γ-dihydroionone and odor-free pristane (2,6,10,14-tetramethylpentadecane), as the major constituents. The ratios of these to one another and to many other minor constituents, varied, depending on sample color and age.

Ambergris, which is a coprolith originating from the sperm whale, has been found only rarely, but for centuries, as jetsam on beaches all over the world. There are no reliable data indicating how long such samples may have remained at sea, with unsubstantiated accounts suggesting maybe decades. Here, we obtained over forty jetsam samples, many collected on known dates, from mostly known beach locations across the globe. Such an inventory of verified jetsam ambergris is unprecedented. Each sample was characterised by analytical methods such as gas chromatography-mass spectrometry (GC-MS). We then determined the radiocarbon ages of some of the samples by well-described accelerator-MS techniques. Surprisingly, some samples of jetsam have remained in the environment for about a thousand years.

Jetsam ambergris, found washed ashore on beaches, is an environmentally modified form of a natural product of Sperm whales which sometimes develops a pleasant odour. Odorous samples have proved valuable in perfumery. Identification of jetsam ambergris by analysis of organic-soluble extracts by Fourier transform infra-red spectroscopy (FTIR) and of derivatised samples by gas chromatography-mass spectrometry (GC-MS) has already been shown. Here, we describe a different method, in which characteristic alkenic protons and carbon atoms of the major constituent ambrein, were identified in whole extracts using nuclear magnetic resonance spectroscopy (NMR). The advantages of employing NMR spectroscopy included rapidity, reduced losses of volatiles compared to GC-MS and detection of non-GC amenable constituents. However, the identities and quantities of co-occurring individual components (e.g. steroids) could not easily be assigned in the unfractionated extracts by NMR spectroscopy, whereas they were by GC-MS, so an approach combining FTIR, GC-MS and NMR spectroscopic methods is advocated.

We describe determination of the dichloromethane-soluble components of 12 samples of the natural product, ambergris, using capillary gas chromatography-mass spectrometry (GC-MS). Ambergris is produced in vivo in about 1% of Sperm whales and is used in perfumery and for odour fixation. Whilst descriptions of ambergris chemistry appeared until about 40 years ago, few accounts of analyses of whole extracts of multiple samples of ambergris by GC-MS have been published before. As expected, our analyses revealed that the major component (up to 97% of the dichloromethane-soluble material) was ambrein, with co-occurring, variable proportions of steroids. Moreover, we report apparently for the first time, mass spectra and retention indices of derivatised ambrein. These data should now allow reliable, rapid confirmation of even small amounts of jetsam, archived museum and customs samples of ambergris and an assessment of ambergris 'quality'.