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Microbial co-cultures have emerged as effective methods for enhancing metabolite production, which surpass the limitations of traditional monoculture approaches by offering enhanced efficiency, lower costs, better stress resistance and more sophisticated processes execution. Co-cultivation strategies, such as microbial interactions, modular co-culture, and microbial communication, are gaining attention for their potential to enhance food-related metabolites. Nevertheless, studies investigating these methods directly within food matrices are significantly scarce. Therefore, this review highlighted various co-cultivation approaches for metabolite enhancement in foods, along with the challenges and future perspectives. The importance of using co-culture methodologies for increasing food metabolite production was demonstrated in this study. It was also indicated that co-culture systems still encounter problems like system complexity, stability and scale-up. Future research should prioritize combining advanced technologies with co-culture systems to overcome challenges, and applying co-culture approaches, especially engaging multi-strains, directly into the food matrices to uncover the whole potential of these strategies. Graphical Abstract

This study produced bovine collagen peptides enriched with phenolics from turmeric, green tea, and rosehip using enzymatic and ultrasound-assisted methods. Phenolic and flavonoid levels ranged 76.75–407.23 and 31.47–300.16 mg g ⁻¹ , respectively. Ultrasound-treated green tea peptides showed the strongest antioxidant activity and digestion stability. During digestion, hydrolysis rose to 74.7%, and molecular weight decreased from 2,114 to 1,042 Da. Glycine and proline remained dominant amino acids. Sensory tests revealed that ultrasound–green tea peptides had the best aroma and flavour. These results highlight the potential of plant-enriched collagen peptides as bioactive and palatable functional food ingredients.

Rose hip (Rosa canina L.), gilaburu (Viburnum opulus L.), barberry (Berberis vulgaris L.) and black barberry (Berberis integerrima L.) are important endemic plants of Turkiye. This study determined the bioactive components, including total phenolic content, flavonoid compounds, and anthocyanin amounts. Antioxidant activity values of Rosa canina L., Viburnum opulus L., Berberis vulgaris L. and Berberis integerrima L. fruits grown in Türkiye were also evaluated after different extractions. According to the results, the highest total phenolic content was determined in the methanol extract of Berberis integerrima L.fruit as 3544.84 (mg GAE/100 g DM). The order of the total amount of phenolic substance for all three solvent extraction systems, from the highest to the lowest, was determined as: Berberis integerrima L.>Viburnum opulus L.>Berberis vulgaris L.>Rose canina L. In terms of total flavonoids, Berberis integerrima L. fruit extracted with methanol had the highest value of 2098.88 (mg CE/100 g). The order of total amount of flavonoid substance for all three solvent extraction systems, from the highest to the lowest, was determined as Berberis integerrima L. > Viburnum opulus L. > Berberis vulgaris L. > Rose canina was detected. The highest amount of Trolox equivalent (DPPH)(ABTS+) was determined as 2.95-3.30 (mM Trolox/100 g DM) in Berberis integerrima L. extracted with methanol. The highest total amount of anthocyanins found in the extracts was obtained for Berberis integerrima L. The highest amounts of vitamin C extracted with ethanol, methanol and water was determined for Berberis integerrima L.24.60; 33.22; 29.22 (mg/ 100 g), respectively. The highest value for CD, CI and T was obtained for Berberis integerrima L. extracted with methanol. The highest score for % R, %Y and % B was obtained for Berberis vulgaris L. exacted with water, for Berberis integerrima L. extracted with ethanol and Berberis integerrima L. extracted with water, respectively. The results demonstrated that the extraction solvent has a critical importance for the releasing of bioactive compounds for each used materials.

Recently, it has been shown that protein phosphatase 2A (PP2A) dysfunction was common in many cancer types and was mediated by various inactivation mechanisms. Although many research studies observed antitumor effect of propolis extracts in various types of cancer, the mechanism of effect are still obscure. In this study, we investigated the effect of propolis on PPP2R1A expression and its relationship with apoptosis in the SW‐620 (colorectal cancer), DU‐145 and PC‐3 (prostate cancer), and MCF‐7 (breast cancer) cell lines, with WI‐38 (healthy fibroblast) cells serving as the control. Moreover, we aimed to investigate the impact of propolis on apoptosis by analyzing apoptosis markers such as tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL), APAF‐1, and caspases‐3, ‐8, and ‐9. Propolis samples were extracted, and their phenolic compounds were quantified using LC‐MS/MS. The RealTime Cell Analysis System‐xCELLigence (RTCA‐SP) device and software were employed to assess cell viability and cytotoxicity of the propolis samples. The IC ₅₀ values for propolis were determined (298 μg/mL for SW‐620, 185.6 μg/mL for DU‐145, 250.7 μg/mL for PC − 3, 292.9 μg/mL for MCF‐7, and 311.2 μg/mL for WI‐38). Subsequently, the effects of propolis on PPP2R1A expression and apoptosis markers (TRAIL, Apaf‐1, and caspases‐3, ‐8, and ‐9) were analyzed. When we compared the healthy cell lines to cancer cell lines, a statistically significant increase in caspase‐3 (3.62‐fold) and in TRAIL (4.38‐fold) was observed in the SW‐620 cell line after the application of propolis. In addition, in the PC‐3 cell line, a 1.4‐fold increase in caspase‐8 was observed compared with the healthy cell line, which is also statistically significant. Our findings indicated that propolis increased the PPP2R1A levels and apoptosis markers in cancer cell lines. It has been suggested that high PPP2R1A levels induced by propolis treatment might activate the apoptosis pathway. In this study, the inducible effect of propolis on PPP2R1A levels, identified as a new target for cancer treatment, was demonstrated for the first time. The findings suggest that propolis holds promise as a potential cancer therapy by increasing PPP2R1A levels, a key molecule in cancer treatment.

Brewer's spent grain (BSG), which is released as a by-product from brewing process, has attracted the attention of scientific research as a low-cost raw material for biotechnological applications. In this study, BSG was used as fermentation medium for production of lactic acid by using different Lb. pentosus strains (Lactobacillus pentosus O157, Lactobacillus pentosus O18, Lactobacillus pentosus O19). Initially, BSG was diluted with 1.25% of H₂SO₄, a solid/liquid ratio (1:8 g/g) for hydrolysis of the medium containing hemicellulose sugars. Lactic acid production conditions by using Lactobacillus pentosus strains were optimized as: pH 6.0, 96 hours at 31°C and 20.0 % of xylose concentration. The maximum amount and yield for lactic acid (22.4 g/L; 13.80 %) was produced with a strain of Lactobacillus pentosus O18, respectively. In the second part of the study, different nitrogen sources (yeast extract, corn steep water, peptone, urea and tryptone) were used for production of lactic acid by using Lactobacillus pentosus O18 strain. In order to meet the complex organic matter needs of lactic acid bacteria, different nitrogen sources were calculated on the basis of equivalent nitrogen (10 g/L of yeast extract) amount. Among used sources the highest yield was obtained with yeast extract followed by peptone.

The fermentation of olives is usually carried out spontaneously by natural microbiota. Spontaneous fermentation has some disadvantages, such as the formation of defects in the end product due to the activities of undesirable microorganisms. The use of starter cultures could be a promising option to provide a more controlled fermentation environment and to reduce the risk of spoilage. Mixed starter culture use (generally selected Lactobacillus strains with or without yeasts) could reduce pH in a shorter time, producing a higher amount of lactic acid and enhancing microbial safety compared to fermentation with starter cultures containing single species or natural fermentation. Their use could also enhance the organoleptical properties of table olives. Particularly the use of yeast (such as strains of W. anomolus, S. cerevisiae) in the fermentation of olives, in combination or sequentially with lactic acid bacteria could result in an increase in volatile compounds and a more aromatic final product.

Sulphur dioxide (SO2) is commonly used as an antioxidant and antimicrobial additive during wine production. Nowadays, consumers preferred foods treated with natural preservatives. The aims this study was to determine the effects of different natural plant extracts as an alternative of sulphur dioxide used in wines. Wine production was done according to the accepted conventional method of red wines (Cabernet sauvignon). The experimental design was achieved by using different plant extracts (grape pomace, rosemary and blueberry) at different concentrations. As control groups were used wine samples produced without addition of SO2. At the end of production basic oenological analyses (total acidity, volatile acidity, pH, dry matter, ash, free and total SO2) and specific wine analyses (total phenols, total flavanols, tartaric ester content and antioxidant activity) were performed. Results demonstrated that each used plant exact have different effects on wine quality parameters. The lowest concentrations of grape pomace extract caused reduction of SO2 and keeping the required wine properties. The highest value of antioxidant activities and total phenols were determined in the wine treated with 25 mg/L SO2 and 1 ml/L rosemary extract (in the 1st mount of storage) and 25 mg/L SO2 and 1 ml/L grape pomace extract (in the 2nd and 3rd mount of storage) as 89.92%, 5550.48 mg/l GAE; 88.51%, 5028.65 mg/l GAE; 88.42%, 4974.25 mg/l GAE, respectively. Results emphasized the importance of used plant extracts and their concentrations. The study demonstrated the possibilities of optimization of SO2 and wines phenols on the base of used natural plant extracts.

Consumption of fermented products rich in antioxidants, anti-inflammatory, anti-diabetes, anti-obesity and anti-carcinogenic compounds is growing into a key strategy to fortify antioxidant defense system. Cabbage products produced by lactic-acid fermentation are chosen via their special microbiota. Considering these special medical properties of fermented-cabbage products as pickled cabbage, sauerkraut and kimchi were produced and evaluated. The data demonstrated that pickled cabbage (109.89±4.74 mg ascorbic acid/100 g d.w.) and its brine (208.14±17.29 mg ascorbic acid/100 g d.w.) exhibited the highest vitamin C content, followed by kimchi (77.42±2.87 mg ascorbic acid/100 g d.w.). The highest total phenolic content was detected in kimchi and sauerkraut with 869.64±70.16 and 438.257±25.05 mg gallic acid equivalents/100 g fresh weight (f.w.), respectively. 50% of the scavenging effect (EC50) values of free radical scavenging activity (DPPH) in kimchi 14.6 mg/ml, followed by sauerkraut (15.52 mg/ml) and pickled cabbage (18.88 mg/ml). Results demonstrated that fermented cabbage products have a great potential with content of bioactive compounds, high antioxidant features promising high beneficial impacts.