Nowadays, an increased concern regarding using natural products for their health benefits can be observed. The aim of this study was to assess and compare several phenolic compounds found in 15- to 60-year-old Douglas fir, silver fir, larch, pine, and spruce needle and bark extracts and to evaluate their antioxidant and antimicrobial activities. Spectrophotometric assays were used to determine the total polyphenol content and the antioxidant activity that was assessed by using the DPPH• radical scavenging assay (RSA), the ferric reducing antioxidant power assay (FRAP), and the ABTS•+ radical cation scavenging assay (ABTS). The phytochemical content was determined by using high-performance liquid chromatography, and the antimicrobial activity was determined by assessing the minimal inhibition concentration (MIC). The results of the study show a total polyphenol content of 62.45–109.80 mg GAE/g d.w. and an antioxidant activity of 91.18–99.32% for RSA, 29.16–35.74 µmol TE/g d.w. for FRAP, and 38.23–53.57 µmol TE/g d.w. for ABTS. The greatest quantity of phenolic compound for most of the extracts was for (+)-catechin, and it had values between 165.79 and 5343.27 µg/g d.w. for these samples. The antimicrobial inhibition for all the extracts was the strongest for Staphylococcus aureus (MIC 62.5–125 µg/mL). The extracts analyzed could be used for their bioactive potential after further investigations.

This study rigorously investigates the bioactive properties and characteristics of extracts derived from the flowers and bark of four distinct Magnolia species: Magnolia champaca, Magnolia denudata, Magnolia grandiflora and Magnolia officinalis. The primary objective is to evaluate the potential application of these extracts in cosmetics and other relevant industries. We used ethanol to extract compounds from these plants and conducted various tests, including spectrophotometry, HPLC, GC-MS, and microbiological analyses. The extracts, particularly rich in polyphenols (55.18 mg GAE/g), displayed significant antioxidant capabilities, with IC 50 values ranging between 9.99 mg/mL and 23.23 mg/mL. We quantified different compounds: phenolic acids (6.259 to 27.883 mg/g dry weight), aglycone flavonoids (61.224 to 135.788 mg/g dw), glycosidic flavonoids (17.265 to 57.961 mg/g dw), and lignans (150.071 to 374.902 mg/g dw). We identified 76 volatile compounds, predominantly oxygenated monoterpenes and sesquiterpene hydrocarbons, which contribute to the antibacterial effectiveness of the extracts. These extracts showed greater inhibitory potential against Gram-negative bacteria than Gram-positive bacteria. The diverse chemical compounds and their demonstrated activities suggest these extracts could be valuable in the cosmetics industry, pharmaceutical industry, or other industries.

The beneficial effects of Juniperus communis L. extracts have been known for a long time. Therefore a scientific knowledge of the chemical profile leading to this bioactivity is required. The aim of this paper is to highlight the influence of geographical origin and harvest time on compositional elements of hydroalcoholic extracts of J. communis pseudo-fruits, but also on their antibacterial properties. The samples were collected from three mountainous area of Romania, during three consecutive months. The total polyphenols were determined by the Folin-Ciocâlteu method, ranging between 12.67 and 14.77 mg GAE/g DW. High-performance liquid chromatography (HPLC) analysis was applied to identify fifteen phenolic compounds from the group of phenolic acids and flavonoids. The antibacterial effect was assessed on Gram-positive and Gram-negative bacterial strains. A good antimicrobial activity was achieved by the extracts of pseudo-fruits harvested during October and November from the Iezerele Cindrelului Botanical Nature Reserve. The obtained results denote a diverse composition of active principles in common juniper pseudo-fruits and moderate antibacterial activity dependent on the harvest time and geographical area.

In light of the growing concerns of consumers who are increasingly turning towards healthier food options, both researchers and producers in the food industry are exploring the use of agro-industrial by-products as nutritionally valuable ingredients. This strategy not only enables the development of value-added food products, but also supports sustainability through the valorization of waste. Blackcurrant pomace (BP), a by-product obtained after juice extraction, has been shown to be rich in bioactive compounds, dietary fiber, antioxidants, and anthocyanin pigments. For these reasons, the innovative aspect of the study was its use of different proportions of BP powder, 5%, 10%, and 15%, when obtaining new varieties of stirred yogurt. This study assesses the impact of BP powder on the stirred yogurt’s antioxidant content, physicochemical properties, color, microbiological characteristics, and sensory qualities. The findings showed that BP powder intensified the yogurts’ coloration and considerably improved their antioxidant activity (which ranged from 8.21 ± 0.35 to 21.15 ± 0.49 µmol TE/g DM) and nutritional quality. The panelists’ positive acceptance was confirmed by sensory evaluation, and the 10% BP formulation (DBBP2) was rated as the most favorable. These results show that BP is a valuable ingredient for enhancing dairy products, creating nutritious, appealing yogurts while promoting sustainable food production and valorization of food waste.

The presence of bioactive compounds in plants with red flowers constitutes a valuable natural resource for the food, pharmaceutical, and medical industries. This paper aims to highlight these characteristics to facilitate the selection of extracts according to market needs. The analyzed parameters can provide valuable insights into the compositional variability of the five red flower plants, as new sources of bioactive compounds and natural antioxidants of plant origin. Five plants with red flowers (Magnolia liliiflora, Chrysanthemum morifolium, Hibiscus sabdariffa, Petunia grandiflora, Rosa hybrida L.) were selected and investigated regarding their polyphenol concentration, total anthocyanins, antioxidant activity, phenolic compounds, and antimicrobial activity. Total polyphenols were found in concentrations ranging from 75.17 ± 0.16 mgGAE/g (C. morifolium) to 107.49 ± 0.19 mgGAE/g (R. hybrida L.), and total anthocyanins between 14.99 ± 0.13 mg Cy-3-Glu/g and 21.66 ± 0.18 mg Cy-3-Glu/g. The antioxidant activity DPPH/IC50 mg/mL for the extract from R. hybrida L. flowers reached a value of 29.35 ± 0.17 mg/g, with ABTS and FRAP achieving maximum values of 49.89 ± 0.24 mmol TE/g and 48.68 ± 0.23 mmol TE/g, respectively. The antibacterial activity was particularly evident against strains commonly encountered in human pathology, Escherichia coli and Staphylococcus aureus, with reduced or no impact on strains of Pseudomonas fluorescens and Proteus mirabilis. The results demonstrated that the extracts from the selected, red-flowered plants contain valuable biologically active compounds in generous quantities, thus recommending their use in the food, pharmaceutical, and medical sectors.

The chemical composition, as well as the antioxidant and antibacterial properties of Artemisia dracunculus L. leaves were studied using four types of solvents for extraction., i.e. ultrapure water, ethanol, methanol and acetic acid. The values reached for total polyphenols (determined by the Folin Ciocâlteu method) were between 77.28±1.48 mg GAE/g d.w. - 192.14±5.33 mg GAE/g d.w. and 46.45±0.11 mg QE/g d.w. - 126.45±0.32 mg QE/g d.w. Antioxidant activity (DPPH) was recorded via IC₅₀ levels between 14.66±0.3 μg/mL and 20.33±0.2 μg/mL. The phenolic compounds, such as flavonoids, coumarins, phenolic acids, were identified using the HPLC method. We analysed the antibacterial activity of the extracts, and the most resistant bacteria were Escherichia coli 29 and Pseudomonas aeruginosa 323 with MIC levels at ≥ 1000µg/mL. Methanolic extracts were the strongest. Artemisia dracunculus L. leaf extracts contain a significant variety of beneficial active chemical and biological compounds, thus the plant is recommended both for culinary and medicinal purposes.