Bronchogen

1 Identity

Short-chain bioregulators (Khavinson peptides). Not an alias of Chonluten, which is the tripeptide Glu-Asp-Gly at 319.27 Da — the two are carried as separate articles in the catalog and are separate molecules 127.19 Da apart.

Sequence

H-Ala-Glu-Asp-Leu-OH (AEDL) as sold — but see the salt and variant note below: the Khavinson group's own peer-reviewed paper gives the sequence as Ala-Asp-Glu-Leu (ADEL), and the two are isobaric. Four residues, all L, free N-terminal alpha-amino group, free C-terminal carboxyl, no disulfide, no acylation, no amidation, no non-proteinogenic residue. Three carboxyl groups (Glu side chain, Asp side chain, C-terminal Leu) against a single basic center, the N-terminal amine, so the molecule is strongly acidic and the counterion pairing runs the opposite way to most peptides in this catalog — a base, not an acid, would be needed to load it, and in practice it is supplied as the acetate or trifluoroacetate of the single amine. No aromatic residue and therefore no 280 nm chromophore.

Molecular formula

C18H30N4O9 (free acid; identical for AEDL, ADEL and AEDI)

Average mass

446.457 Da (C18H30N4O9) from the tetrapeptide composition on IUPAC 2021 conventional atomic weights; 446.46 is that same figure rounded.

Monoisotopic mass

446.2013 Da neutral. Working ions: [M+H]+ m/z 447.2086, [M-H]- m/z 445.1940, [M+Na]+ m/z 469.1905. A plus or minus 5 ppm window on the neutral is plus or minus 0.0022 Da.

Salt / variant note

Three isobaric molecules, and this is the worst case in the block because arithmetic cannot separate any of them. (1) AEDL, Ala-Glu-Asp-Leu — what every tracked seller prints: five independent sellers all give Ala-Glu-Asp-Leu, and it is the ordering claimed in US Patent 7,625,870. (2) ADEL, Ala-Asp-Glu-Leu — the ordering used by Khavinson's own group in the 2011 Bulletin of Experimental Biology and Medicine paper. Positions 2 and 3 transposed. C18H30N4O9, 446.457 avg, 446.20128 mono — identical to AEDL to every decimal place, and identical on amino-acid analysis too. (3) AEDI, the Leu4/Ile4 pair, also C18H30N4O9, also 446.20128 mono, and indistinguishable even by MS/MS b/y series since Leu and Ile are isomeric; only chiral or specialized fragmentation methods separate that pair. Nearby family members a careless certificate could confuse: KEDG 447.445 avg / 447.19653 mono (+0.99 Da), AEDN 447.401 avg / 447.16014 mono (+0.94 Da), AEDM 464.490 / 464.15770, AEDP (Cortagen) 430.414 / 430.16998, AEDG (Epitalon) 390.349 / 390.13868, AEDR (Cardiogen) 489.486 / 489.21833, AED (Cartalax) 333.297 / 333.11721. Several of those articles are filled in the same facility as this one, so the separation between adjacent articles has to be arithmetically visible on the certificate. KEDG and AEDN both sit within one dalton, so a certificate reporting "446" or "447" without decimals cannot exclude either. Salt forms are the remaining axis: with a single basic center the counterion load is comparatively light, but on a 446 Da molecule even one mole of trifluoroacetate is 20.4 percent of the article mass. Three carboxylates against one amine make this an acidic peptide with a light counterion load, which is why the water figure and not the counterion figure is the larger threat to the label claim here.

2 Class & testing panel

Form

Single article

Testing panel

P1 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

In-vitro and rodent literature concentrated in publications from the originating Russian institute, the Saint Petersburg Institute of Bioregulation and Gerontology, and its collaborators, with limited independent replication outside that network and a substantial fraction appearing in Russian-language journals with restricted indexing. The specific bronchogen citation is PubMed 21240358, Bulletin of Experimental Biology and Medicine 2011, a biophysical DNA-thermostability study. The group-level literature includes PMID 12374906, PMID 31808038 (DOI 10.1007/s12015-019-09938-8), PMID 11276315, PMID 23734519, PMID 24003726 and PMID 32593244, of which the two Advances in Gerontology papers are reviews by the originating group rather than primary randomized trials. No randomized controlled human trial and no ClinicalTrials.gov registration were identified. No marketing authorization in any jurisdiction. The class evidence is graded D.

4 Storage & specification

Storage

Lyophilized powder, -20 degrees C plus or minus 5 degrees C, desiccated, protected from light. 2 to 8 degrees C is acceptable for transit and for working stock held no longer than 30 days; shipping validation covers a 72-hour excursion to 25 degrees C. Sealed vials are equilibrated to room temperature before opening. On a 446 Da peptide the water figure is a large fraction of the label claim, so the desiccant and the equilibration instruction are specification items and not housekeeping. The presentations are a 100 mg vial and a 500 mg bulk vial.

Shelf life

Provisional 24 months at -20 degrees C plus or minus 5 degrees C, pending the company's own long-term and accelerated stability data on the first three lots. A short all-L peptide with no disulfide, no methionine, no tryptophan and no labile motif is expected to support this interval, but the interval stays provisional until the data exist. Water content and residual counterion are the attributes to trend, since neither gross purity nor mass will move on this molecule before the net peptide figure does.