Botanic Origin of Propolis Extract Powder Drives Contrasted Impact on Diabesity in High-Fat-Fed Mice

Propolis extracts are considered as nutraceutical products with potentialities towards obesity and comorbidities management. Nevertheless, propolis extracts composition is highly variable and depends on the botanic origin of plants used by the bees to produce propolis. This study aims to evaluate the differential effect of poplar propolis extract powder (PPEP), Baccharis propolis extract powder (BPEP), and/ or Dalbergia propolis extract powder (DPEP) on obesity and glucose homeostasis in high-fat-fed mice. PPEP supplementation reduced high-fat (HF)-mediated body weight gain, adiposity index, and improved glucose homeostasis in male C57Bl/6J mice that were submitted to a high-fat diet for 12 weeks, whereas BPEP, DPEP, or a mix of the three PEPs did not modify those parameters. Adipose tissue (AT) gene expression profiling highlighted an induction of mRNA related to lipid catabolism and an inhibition of mRNA coding for inflammatory markers. Several Nrf2 target genes, coding for antioxidant enzymes, were induced in AT under PPEP effect, but not by other PEP. Interestingly, representative PPEP polyphenols mediated the induction of Nrf2 target genes cell-autonomously in adipocytes, suggesting that this induction may be related to the specific polyphenol content of PPEP. Whereas PPEP supplementation has demonstrated a clear potential to blunt the onset of obesity and associated comorbidities, other PEPs (from Baccharis and Dalbergia) were inefficient to support their role in preventive nutrition.

Front-Face Fluorescence of Honey of Different Botanic Origin: A Case Study from Tuscany (Italy)

Honey is a natural pure food produced by honeybees from the nectar of various plants, and its chemical composition includes carbohydrates, water, and some minor compounds, which are very important for honey quality and authentication. Most of honey’s minor components are related to the botanic origin, climate, and geographic diversity. In this work, we report an original case study on monofloral honey samples of twelve different botanic origins produced in Tuscany (Italy) based on the ‘semi-quantitative’ analysis of emission, excitation, and synchronous front-face fluorescence spectra. This is the first front-face fluorescence study of Italian honey samples and, to our knowledge, the first fluorescence investigation of honey from inula (Inula viscosa (L.) Aiton), marruca (Paliurus spina-christi Mill.), lavender (Lavandula L. 1753), sulla (Hedysarum coronarium L.), arbutus (or strawberry tree) (Arbutus unedo L., 1753), and alfalfa (Medicago sativa L.) plants. Results obtained from fluorescence spectroscopy are discussed in terms of characteristic spectral emission profiles typical of honey of different botanic origins. Moreover, the spectral analysis based on the decomposition of the front-face fluorescence (FFF) spectra in terms of single main fluorophores’ components is here proposed to identify several minor compounds, such as amino acids, phenolic acids, vitamins, and other fluorescent bioactive molecules.