Derived from renewable sources like corn starch or sugarcane, poly(lactic acid) (PLA) presents an eco-friendly alternative to traditional petroleum-based plastics. PLA lacks inherent functional groups, posing a challenge for certain applications. The modification and functionalization of PLA contribute to the facilitation of innovative applications across diverse fields. To address this limitation, in this study a bioactive compound, caffeic acid, strategically grafted the onto poly(D,L-lactide)-b-poly(2-hydroxyethyl methacrylate) block copolymer (PLA-b-PHEMA). The resulting caffeic acid grafted copolymer (PLA-b-PHEMA-g-CA) was characterized by size exclusion chromatography, NMR, UV–Vis and FT-IR spectroscopies, and then blended with commercial PLA to produce films. The synthesis involves polymerizing 2-hydroxyethyl methacrylate with a poly(D,L-lactide) macroinitiator via ATRP method, yielding PLA-b-PHEMA. Subsequent functionalization via Steglich esterification yields PLA-b-PHEMA-g-CA. Characterization indicated a grafting ratio of 60.7%. Both grafted copolymer and films exhibited antioxidant property and antimicrobial effect against S. aureus and E. coli, showcasing potential applications in sustainable materials.

Abstract Ethanol has been widely used for the extraction of propolis. Due to its certain disadvantages, there has been an ongoing search to find alternative non‐ethanolic extraction solvents. This study aimed to compare the phenolics, antioxidant, and antibacterial activity of propolis extracts prepared with 70% ethanol (EWE), propylene glycol (PGE), and L‐arginine solution (BE). All extracts were subjected to an in vitro simulated digestion procedure, and the phenolic profile of non‐digested and digested samples was determined by using LC–MS/MS. Additionally, the change in total phenolic (TPC), total flavonoid content (TFC), and antioxidant capacities were determined at each digestion phase. TPC and TFC of non‐digested propolis extracts had similar values, although BE showed higher antioxidant capacity (p < .05). The amount of TPC reached or transformed at the intestinal stage was higher for BE and PG compared to EWE. BE also provided the highest antioxidant capacity assay in digested samples. The most common phenolics were pinocembrin, pinobanskin, galangin, and CAPE in non‐digested extracts. However, their concentration was drastically reduced by digestion, and their recovery (R%) ranged from 0% to 9.38% of the initial amount detected in the non‐digested extracts. Chrysin was the most bioaccessible flavonoid in all extracts. Among phenolic acids, the highest R% was determined for trans‐cinnamic acid (22.14%) from BE. All extracts showed in vitro inhibitory activity against Escherichia coli and Staphylococcus aureus. This study suggests that an L‐arginine solution could be used as an alternative solvent to ethanol and propylene glycol for propolis extraction.

Propolis is mainly composed of plant resins, and its type is named according to the primary plant origin in its composition. Identification of propolis botanical origin is essential for predicting and repeating its pharmacological activity because of the variations in chemical composition. This study aimed to compare chemical composition of black poplar (Populus nigra L.) type-propolis (PR1 and PR2) and Eurasian aspen (P. tremula L.)-type propolis (PR3) by liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique and to evaluate their biological activity profiles. According to LC-MS/MS results, in addition to marked caffeic acid phenethyl ester content in PR1 and PR2, flavonoid aglycones such as pinocembrin, chrysin, pinobanksin, and galangin were found to be dominant in these samples. On the other hand, PR3 contained relatively high concentrations of phenolic acids such as ferulic acid, p-coumaric acid, and trans-cinnamic acid. The anti-estrogenic activity test showed that PR2 exerted the highest anti-estrogenic activity by inhibiting cell proliferation by 44.6%. All propolis extracts showed anticancer activity, which was justified by decreasing activity on the 3D spheroid size in a concentration-dependent manner. Besides, all extracts showed moderate or potent antimutagenic activity in Salmonella typhimurium TA98 and TA100 strains with and without metabolic activation, respectively. In addition, the Comet assay results revealed that propolis extracts have a geno-protective effect against H2O2-induced DNA damage in CHO-K1 cells at 0.625 and 1.25 μg/mL concentrations. Overall, the result of this study may help in preparing standardized propolis extracts and developing products with defined pharmacological benefits in the food supplements industry.

Honey bees need pollen and nectar sources to survive in nature. Particularly, having young bees in colonies is vital before wintering, and proper feeding is necessary to achieve this. In the present study, the effect of feeding with pollen sources of different protein content on colony performance, wintering ability and in-vitro longevity of colonies that weakened after feeding with pine honey in autumn, or that needed to enter the winter period, was investigated. The experiment was carried out in 48 colonies divided into six groups as follows: control, syrup, mixed pollen, Cistus creticus pollen (Pink rock-rose), Papaver somniferum pollen (Opium poppy), and commercial bee cake groups. In particular, the P. somniferum pollen group was different (p < 0.01) from the other experiment groups with the number of bee frames (3.44), the area with brood (1184.14 cm2) and the wintering ability of 92.19%. The effect of nutritional differences on survival was found to be statistically significant in vitro and this supports the colony results in the natural environment (p < 0.001). The P. somniferum group has the longest longevity with 23 days. Pollen preferences of honey bees were P. somniferum, C. creticus, and mixed pollen, respectively.

The majority of the authentic pine honey samples fail from C-4% sugar test. Pine honey is generally characterized by small-sized insoluble honeydew elements, and these can form an appreciable amount of precipitate during protein flocculation. These substances may shift the protein-centric δ13C (13C/12C) values inaccurately. In this study, honey proteins were isolated, enriched, and cleaned-up prior to flocculation by applying the optimized and validated ultrafiltration method. Authentic honeys were analyzed along with adulterated samples using both AOAC 998.12 and novel protocol. When the interfering substances were eliminated, most of the samples, which were interpreted as adulterated according to the AOAC's method previously, were identified as authentic. It has been proven that inconsistent protein measurements may cause false positivity. These findings revealed that the developed method could correct the artificially high C-4% results and the proposed modification will pave the way for increasing the overall reliability of the test.

A versatile sample pretreatment method for the honey matrix is still needed for any proteomic-based investigations. Invertase and diastase are the most important enzymes in the maturation of pine honey and the origin of these enzymes are attributed to the bee's hypopharyngeal glands (HPG). In our study, we aimed to isolate and enrich these enzymes as model proteins representing the honey proteome in an efficient and practical way. As authenticity comparison, isolating the same enzymes from HPG samples was also accomplished. For yielding pine honey crude protein isolate, as a tandem two-step approach, stirred cell ultrafiltration followed by centrifugal ultrafiltration (CUF) protocol was determined after experimental optimization. HPGs were dissected from the Apis mellifera L. and proteins were extracted by using a bead beater followed by concentration using CUF. Protein profiles of pine honey and HPG were compared by SDS-PAGE. The resulting protein concentrations, enzyme activities, and the cleaning efficiencies of the applied techniques were evaluated and optimized using the Bradford assay, modified enzyme activity assays, and sugar profiling method developed at HPLC-RID. The novel pretreatment method provided invertase at 1055.1 U/kg activity and diastase at 693.3 Shade U/g activity with yields of 900.9% and 2432.6%, respectively. The final crude protein isolate can be interpreted as reference material at any authenticity and quality assays of honey. The obtained crude protein extract will pave the way for high throughput proteomic investigations at the honey matrix. Furthermore, this template methodology could be scaled up in the industry for natural enzyme production.

A broad range of evidence has confirmed that natural products and essential oils might have the potential to suppress COVID-19 infection. Therefore, this study aimed to develop an oral/throat spray formulation for pro-phylactic use in the oral cavity or help treatment modalities. Based on a reference survey, several essential oils, a cold-pressed oil, and propolis were selected, and cytotoxicity and antiviral activity of each component and the developed spray formulation were examined against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection using Vero E6 cells. Anti-inflammatory, antimicrobial, and analgesic activities as well as mutagenicity and anti-mutagenicity of the formulation were analysed. Forty-three phenolics were identified in both propolis extract and oral/throat spray. The spray with 1:640-fold dilution provided the highest efficacy and the cytopathic effect was delayed for 54 h at this dilution, and the antiviral activity rate was 85.3%. A combi-nation of natural products with essential oils at the right concentrations can be used as a supplement for the prevention of SARS-CoV-2 infection.

Çalışma kapsamında, zengin bitki örtüsüne sahip ülkemizin 6 farklı bölgesindeki 21 farklı ilinde üretilen 34 adet arı poleni örneklerinin nem, kül, protein, yağ, lif değerleri ve şeker profili araştırılmıştır. Elde edilen sonuçlardan numunelerin karbonhidrat ve enerji değerleri hesaplanmıştır. Çalışma sonunda ortalama protein % 18,8±3,2 ; yağ % 7,6±1,6 ; kül % 2±0,5 ; lif % 14,4±2,7; toplam şeker %40,9±6,4; karbonhidrat değeri %54,6±5,8; glukoz miktarı %14,8±1,9; fruktoz miktarı %19,5±2,0; sakaroz miktarı %3,8±3,4; maltoz miktarı %0,9±0,6 ve turanoz miktarı %1,2±0,6 olarak saptanmıştır. Şekerlerden izomaltoz ve erloz sadece birkaç numunede tespit edilmiş, trehaloz, melezitoz, maltotrioz ise genel olarak numunelerde belirlenememiştir. İstatiksel olarak analiz sonuçları değerlendirildiğinde protein miktarı dışındaki parametrelerde bölgeler arasında önemli bir farklılıklar olduğu belirlenmiştir (p>0.05). Özellikle Doğu Anadolu bölgesinden sağlanan polenlerin diğer bölgelerden sağlananlara göre birçok parametrede ayrıldığı görülmektedir.

The main aim of this study is to characterise Turkish propolis and to determine the bioactive composition of it. 86 different propolis samples were collected from 25 different provinces in Turkey. Chemical, microscopic and functional properties of Turkish propolis have been determined. Also Turkish propolis was compared propolis types from other countries. Each sample was analyzed for moisture content, beeswax content, total phenolics, antioxidant activity, flavonoid profile, pollen profile and mineral content. Moisture, ash and beeswax content were analyzed by AOAC934.01, IHC methods, respectively. Total phenolic contents, antioxidant activities and flavonoid profile were analyzed by Folin Ciocalteu, DPPH using Spectrophotometer and by HPLC-PDA, respectively. Possible botanical sources of the samples were investigated using microscopic method and mineral contents were determined using ICP-MS. It was determined that the results vary depending on flora, season and climate conditions. It was specified that the flavonoid profile of Turkish propolis showed differences from other types of propolis. With flavonoid profile analysis, totally 38 different bioactive compounds were analyzed. Caffeic Acid, p-Coumaric Acid, Ferrulic Acid, M-Coumaric Acid, 3,4-Dimethoxy Cinnamic Acid, trans-Cinnamic Acid, Pinobanksin, Quercetin, Naringenin, Luteolin, Genistein, Hesperetin, Kaempferol, Apigenin, Pinocembrin, CAPE, Chrysin and Galangin were mainly determined in Turkish Propolis. Possible botanical sources of propolis were determined as Pinus spp. , Salix spp. , Castanea spp., Eucalyptus spp. , Quercus spp. and Populus spp. . Different regions mainly contains Iron, Chromium, Copper, Calcium, Magnesium, Selenium, Manganese and Zinc. It was specified that flavonoid content of Turkish propolis showed differences from other propolis types.