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Beekeeping is an important agricultural and commercial activity globally practiced. Honey bee is attacked by certain infectious pathogens. Most important brood diseases are bacterial including American Foulbrood (AFB), caused by Paenibacillus larvae (P. larvae), and European Foulbrood (EFB) by Melissococcus plutonius (M. plutonius) in addition of secondary invaders, e.g. Paenibacillus alvei (P. alvei) and Paenibacillus dendritiformis (P. dendritiformis). These bacteria cause the death of larvae in honey bee colonies. In this work, antibacterial activities of extracts, fractions, and isolated certain compounds (nominated 1-3) all originated from moss, Dicranum polysetum Sw. ( D. polysetum), were tested against some honey bee bacterial pathogens. Minimum inhibitory concentration, minimum bactericidal concentration, and sporicidal values ​​of methanol extract, ethyl acetate, and n-hexane fractions ranged between 10.4 and 18.98, 83.4-303.75 & 5.86-18.98 µg/mL against P. larvae, respectively. Antimicrobial activities of the ethyl acetate sub-fractions (fraction) and the isolated compounds (1-3) were tested against AFB- and EFB-causing bacteria. Bio-guided chromatographic separation of ethyl acetate fraction, a crude methanolic extract obtained from aerial parts of D. polysetum resulted in three natural compounds: a novel one, i.e. glycer-2-yl hexadeca-4-yne-7Z,10Z,13Z-trienoate (1, dicrapolysetoate; given as trivial name), in addition to two known triterpenoids poriferasterol (2), and γ-taraxasterol (3). Minimum inhibitory concentration ranges were 1.4-60.75, 8.12-65.0, 2.09-33.44 & 1.8-28.75 µg/mL for sub-fractions, compounds 1, 2, and 3, respectively., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Pregnancy toxaemia is a metabolic disorder that results from an inadequate energy supply to the growing maternal-fetal unit. The mechanism underlying the pathogenesis of the syndrome has not been fully clarified; however, a key role for cytokines and chemokines including interleukin 1 beta (IL-1 beta), tumour necrosis factor alpha (TNF-alpha) and monocyte chemotactic protein 1 (MCP-1) has been indicated in women and experimental animals. However, information on the maternal plasma levels of IL-1 beta, TNF-alpha and MCP-1 in ewes with pregnancy toxaemia is limited. Thus, the present study was designed to determine plasma IL-1 beta, TNF-alpha and MCP-1 concentrations in ewes with severe (n=6) and mild (n=4) naturally occurring pregnancy toxaemia and in uncomplicated pregnant ewes (n=10) using enzyme-linked immunosorbent assay (ELISA). All ewes with pregnancy toxaemia had significantly lower body temperature and respiratory rate than uncomplicated pregnant ewes (p<0.05). With the highest concentrations in severe cases, heart rate, proteinuria and serum uric acid levels as well as plasma IL-1 beta, TNF-alpha and MCP-1 were significantly different among all three groups (p<0.05). The plasma concentrations of IL-1 beta in control ewes and ewes with mild and severe toxaemia were 15.81 +/- 3.90 pg/ml, 23.83 +/- 2.42 pg/ml and 34.55 +/- 8.03 pg/ml, respectively. The plasma concentrations of TNF-alpha in control ewes and ewes with mild and severe toxaemia were 7.71 +/- 1.61 pg/ml, 16.13 +/- 3.63 pg/ml, and 22.85 +/- 3.64 pg/ml, respectively. The plasma concentrations of MCP-1 in control ewes and ewes with mild and severe toxaemia were 101.70 +/- 9.86 pg/ml, 134.75 +/- 6.24 pg/ml, and 157.67 +/- 9.69 pg/ml, respectively. Moreover, plasma IL-1 beta, TNF-alpha and MCP-1 levels were positively correlated with clinical and well-establish biochemical parameters of pregnancy toxaemia, serum uric acid and proteinuria (p<0.01). Concomitant increase of plasma IL-1 beta, TNF-alpha and MCP-1 concentrations along with serum uric acid, proteinuria, and worsening of the clinical signs indicates that such cytokines are involved in the aetiopathogenesis and in perpetuation of the local and systemic inflammatory reactions in pregnancy toxaemia in ewes. Hence, plasma IL-1 beta, TNF-alpha and MCP-1 may potentially serve as markers to monitor prognosis of pregnancy toxaemia in ewes.