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Key message Sustainability and safety aspects of plant cell cultures as food are presented. Applicability of dairy side streams as carbon source and use of natural growth enhancers in cultivation are shown. Abstract Biotechnologically produced cellular products are currently emerging to replace and add into the portfolio of agriculturally derived commodities. Plant cell cultures used for food could supplement current food production. However, still many aspects need to be resolved before this new food concept can enter the market. Issues related to sustainability and safety for human consumption are relevant for both consumers and regulators. In this study, two plant cell cultures, deriving from arctic bramble (Rubus arcticus) and birch (Betula pendula), were cultivated using lactose-rich dairy side streams as alternative carbon sources to replace sucrose. Biomasses were comparable to those of original plant cell culture media when up to 83% and 75% of the original sucrose was replaced by these side streams for arctic bramble and birch cell cultures, respectively. Furthermore, nutritional composition or sensory properties were not compromised. Synthetic plant growth regulators were replaced by natural components, such as coconut water and IAA for several subculture cycles. Finally, it was shown that only trace amounts of free growth regulators are present in the cells at the harvesting point and assessment by freshwater crustaceans assay indicated that toxicity of the cells was not exceeding that of traditionally consumed bilberry fruit.

Plant cell cultures from cloudberry (CL), lingonberry (LI), stone berry (ST), arctic bramble (AB), and strawberry (SB) were studied in terms of their polyphenol and carotenoid composition, antioxidant activity, antihemolytic activity and cytotoxicity effects on cancerous cells. High-resolution mass spectrometry data showed that LI, presented the highest antioxidant activity, contained the highest contents of flavones, phenolic acids, lignans, and total carotenoids, while CL, ST and SB presented the opposite behavior. AB and SB presented the lowest FRAP and CUPRAC values, while AB and CL presented the lowest reducing power. SB presented the lowest antioxidant activity measured by single electron transfer assays and the lowest content of lignans, phenolic acids, and flavones. CL and LI decreased the viability of in vitro mammary gland adenocarcinoma while only LI decreased the viability of in vitro lung carcinoma and showed protective effects of human erythrocytes against mechanical hemolysis.

Staphylococcus aureus is the most common cause of surgical site infections and its treatment is challenging due to the emergence of multi-drug resistant strains such as methicillin-resistant S. aureus (MRSA). Natural berry-derived compounds have shown antimicrobial potential, e.g., ellagitannins such as sanguiin H-6 and lambertianin C, the main phenolic compounds in Rubus seeds, have shown antimicrobial activity. The aim of this study was to evaluate the effect of sanguiin H-6 and lambertianin C fractionated from cloudberry seeds, on the MRSA growth, and as treatment of a MRSA biofilm development in different growth media in vitro and in vivo by using a murine wound infection model where sanguiin H-6 and lambertianin C were used to prevent the MRSA infection. Sanguiin H-6 and lambertianin C inhibited the in vitro biofilm development and growth of MRSA. Furthermore, sanguiin H-6 showed significant anti-MRSA effect in the in vivo wound model. Our study shows the possible use of sanguiin H-6 as a preventive measure in surgical sites to avoid postoperative infections, whilst lambertianin C showed no anti-MRSA activity.

We have developed an organic solvent-free process to enrich natural antimicrobials from the important Nordic Rubus berry species, especially from cloudberry. The process utilizes industrial berry byproducts as raw-material, and it is based on seed sanding technology and water-based extraction. The extracts showed strong antimicrobial activity against Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). A concentration of 5 mg/mL totally eliminated these bacteria in 24 h. Effects against Gram-negative bacteria were modest. Polyphenol analysis of the hydrothermal extracts showed that the antimicrobial activity is correlated to ellagitannins, mainly dimeric sanguiin H-6 and sanguiin H-10 isomers. Sanguiin H-10 is not commonly found in intact cloudberry seeds, but it is formed from the dimeric and trimeric ellagitannins, during the extraction. Surprisingly hydrothermal extracts had no or minor effects on beneficial bacteria, Lactobacillus rhamnosus. This interesting finding might offer an application potential in controlling skin microbial pathogens, for example, in wound healing.

Main conclusion: The polyphenol profiles of 18 cell cultures from 12 plant species were screened. The detected polyphenol fingerprints were diverse and differed from polyphenol profiles typically found in corresponding plant species. Cell cultures originating from 12 different plant species growing or grown in the Nordic countries were screened for their ability to synthesize polyphenols to assess their suitability for future studies and applications. The focus was on plant families Rosaceae and Ericaceae. On average, the Rosaceae cultures were the most efficient to produce hydrolysable tannins and the Ericaceae cultures were the most efficient to produce proanthocyanidins. This is in line with the general trend of polyphenols found in Rosaceae and Ericaceae leaves and fruits, even though several individual cell cultures differed from natural plants in their polyphenolic composition. Overall, several of the studied cell cultures exhibited capability in producing a large variety of polyphenols, including tannins with a high molecular weight, thus also showing promise for further studies concerning, for example, the accumulation of specific polyphenols or biosynthesis of polyphenols in the cell cultures.

Phenolic composition and bioactivity of cloudberry was modified by bioprocessing, and highly bioactive fractions were produced by dry fractionation of the press cake. During fermentation polymeric ellagitannins were partly degraded into ellagic acid derivatives. Phenolic compounds were differentially distributed in seed coarse and fine fractions after dry fractionation process. Tannins concentrated in fine fraction, and flavonol derivatives were mainly found in coarse fraction. Ellagic acid derivatives were equally distributed between the dry fractions. Fermentation and dry fractionation increased statistically significantly anti-adhesion and anti-inflammatory activity of cloudberry. The seed fine fraction showed significant inhibition of P fimbria-mediated haemagglutination assay of uropathogenic Escherichia coli. The seed coarse fraction significantly reduced NO and IL-6 production and iNOS expression in activated macrophages. Fermentation did not affect antimicrobial activity, but slight increase in activity was detected in dry fractions. The results indicate the potential of cloudberry in pharma or health food applications.

Plant cell cultures from cloudberry, lingonberry and stoneberry were studied in terms of their nutritional properties as food. Carbohydrate, lipid and protein composition, in vitro protein digestibility and sensory properties were investigated. Dietary fibre content varied between 21.2 and 36.7%, starch content between 0.3 and 1.3% and free sugar content between 17.6 and 33.6%. Glucose and fructose were the most abundant sugars. High protein contents between 13.7 and 18.9% were recorded and all samples had a balanced amino acid profile. In vitro protein digestion assay showed hydrolysis by digestive enzymes in fresh cells but only limited hydrolysis in freeze-dried samples. The lipid analysis indicated that the berry cells were rich sources of essential, polyunsaturated fatty acids. In sensory evaluation, all fresh berry cells showed fresh odour and flavour. Fresh cell cultures displayed a rather sandy, coarse mouthfeel, whereas freeze-dried cells melted quickly in the mouth. All in all the potential of plant cells as food was confirmed.

Cosmetics are moving towards pharma and cosmeceuticals are entering the market. Modern biotechnology offers many advantages to develop new type of ingredients for industrial applications in a sustainable way. Due to the arctic growth conditions Nordic wild berries are rich sources of natural biomolecules with multifunctional effects to the skin. We have shown that phenolic compounds in berries very efficiently inhibit the growth of many human pathogens including skin pathogens, such as Staphylococcus aureus, S. epidermis and Pseudomonas aeruginosa without effecting the growth of beneficial bacteria. Several mechanisms of action, including the weakening of the outer membrane of Gram- negative bacteria, are involved in the growth inhibition. More interestingly, various berry phenolics are shown to specifically block cell-to-cell signalling (quorum sensing) in a bacterial community. Thus these phytochemicals can act in cosmetic preparations in dual way, as natural preservatives to prevent spoilage of the product, and as stabilizers of healthy skin microbiota by inhibiting the growth of harmful skin microbes and by supporting the growth of beneficial microbes.Bioprocessing including enzyme treatment and fermentation combined with special dry fractionation technologies of the berry material has resulted in increased bioactivities. Using plant cell and tissue culture technology whole biosynthetic capacity of the plant can be advantaged and even totally new beneficial compounds for the skin can be produced. The unusual phenolic profile of the cultured berry cells, as well as their fatty acid composition with a high proportion of α-linolenic acid and high protein content makes them a unique and interesting alternative for cosmetic industry. Efficient utilization of the biomolecules requires controlled delivery systems into the skin, such as microcurrent patches developed at VTT, which are based on renewable enzyme catalysts and renewable materials. The possibilities using natural plant cell-derived ingredients combined with new delivery system will also be discussed.

Obesity and its consequences on cardiometabolic health have been associated to low-grade inflammation. Anthocyanins are anti-inflammatory compounds in diet, and the major group of polyphenols found in wild European blueberries, bilberries (Vaccinium myrtillus). We have studied the effects of a bilberry-rich diet on inflammation and gene expression profile in peripheral blood mononuclear cells (PBMCs) in subjects with features of the metabolic syndrome. In a randomized, controlled dietary intervention study the bilberry group (n=15) consumed bilberries or berry products equivalent to 400 g of fresh berries daily for 8 weeks, while the participants in the control group (n=12) maintained their habitual diets. Inflammatory markers were measured before and after the intervention. The microarray profiling was done from 3 subjects in the bilberry group and further QPCR expression analyses from all subjects in both groups at both timepoints. From 50 differentially expressed transcripts for mRNA (P>0.005), five candidate genes; WDSUB1, COX7B, RGS18, DAPP1 and TICAM1, were randomly selected for QPCR analyses. To further explore the interplay of dietary change and the affected pathways additional genes of LBP, TNFRSF12A, RIPK-1, Ly96 (MD2), TAB-2 (Toll-like receptor pathway); CD19, CD72 (B-cell receptor pathway) MMD, CCR2 (Monocyte and macrophage associated genes) were selected for QPCR analyses. Bilberries tended to decrease plasma concentrations of hsCRP, IL-6 and LPS (lipopolysaccharide, endotoxin). An inflammation score based on these markers and TNF-Alpha showed different trends between the bilberry and control groups. These changes were accompanied by differential expression in PBMCs of MMD and CCR2, transcripts associated with monocyte activation and recruitment, respectively. Our results indicate that high regular bilberry intake may reduce endotoxemia and chronic inflammation, the latter especially by directing the immunity away from overactive innate cell mediated responsiveness. Bilberry consumption may therefore decrease the long term risk of cardiovascular and metabolic diseases

Tannins are a unique group of phenolic metabolites with molecular weights between 500 and 30000 Da, which are widely distributed in almost all plant foods and beverages. Proanthocyanidins and hydrolysable tannins are the two major groups of these bioactive compounds, but complex tannins containing structural elements of both groups and specific tannins in marine brown algae have also been described. Most literature data on food tannins refer only to oligomeric compounds that are extracted with aqueous-organic solvents, but a significant number of non-extractable tannins are usually not mentioned in the literature. The biological effects of tannins usually depend on their grade of polymerisation and solubility. Highly polymerised tannins exhibit low bioaccessibility in the small intestine and low fermentability by colonic microflora. This review summarises a new approach to analysis of extractable and non-extractable tannins, major food sources, and effects of storage and processing on tannin content and bioavailability. Biological properties such as antioxidant, antimicrobial and antiviral effects are also described. In addition, the role of tannins in diabetes mellitus has been discussed. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Gram-negative bacteria are important food spoilage and pathogenic bacteria. Their unique outer membrane (OM) provides them with a hydrophilic surface structure, which makes them inherently resistant to many antimicrobial agents, thus hindering their control. However, with permeabilizers, compounds that disintegrate and weaken the OM, Gram-negative cells can be sensitized to several external agents. Although antimicrobial activity of plant-derived phenolic compounds has been widely reported, their mechanisms of action have not yet been well demonstrated. The aim of our study was to elucidate the role of selected colonic microbial metabolites of berry-derived phenolic compounds in the weakening of the Gram-negative OM. The effect of the agents on the OM permeability of Salmonella was studied utilizing a fluorescence probe uptake assay, sensitization to hydrophobic antibiotics, and lipopolysaccharide (LPS) release. Our results show that 3,4-dihydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 3-(3,4-dihydroxyphenyl)propionic acid (3,4-diHPP), 3-(4-hydroxyphenyl)propionic acid, 3-phenylpropionic acid, and 3-(3-hydroxyphenyl)propionic acid efficiently destabilized the OM of Salmonella enterica subsp. enterica serovar Typhimurium and S. enterica subsp. enterica serovar Infantis as indicated by an increase in the uptake of the fluorescent probe 1-N-phenylnaphthylamine (NPN). The OM-destabilizing activity of the compounds was partially abolished by MgCl2 addition, indicating that part of their activity is based on removal of OM-stabilizing divalent cations. Furthermore, 3,4-dihydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, and 3,4-diHPP increased the susceptibility of S. enterica subsp. enterica serovar Typhimurium strains for novobiocin. In addition, organic acids present in berries, such as malic acid, sorbic acid, and benzoic acid, were shown to be efficient permeabilizers of Salmonella as shown by an increase in the NPN uptake assay and by LPS release.

Berry fruits are rich sources of bioactive compounds, such as phenolics and organic acids, which have antimicrobial activities against human pathogens. Among different berries and berry phenolics, cranberry, cloudberry, raspberry, strawberry and bilberry especially possess clear antimicrobial effects against, e.g. Salmonella and Staphylococcus. Complex phenolic polymers, like ellagitannins, are strong antibacterial agents present in cloudberry and raspberry. Several mechanisms of action in the growth inhibition of bacteria are involved, such as destabilisation of cytoplasmic membrane, permeabilisation of plasma membrane, inhibition of extracellular microbial enzymes, direct actions on microbial metabolism and deprivation of the substrates required for microbial growth. Antimicrobial activity of berries may also be related to antiadherence of bacteria to epithelial cells, which is a prerequisite for colonisation and infection of many pathogens. Antimicrobial berry compounds may have important applications in the future as natural antimicrobial agents for food industry as well as for medicine. Some of the novel approaches are discussed.

Gut is the site of active fermentation of non-digestible dietary components (dietary fibre and prebiotics) as well as bioconversion and absorption of plant-derived phenolics. These compounds have an important role in gut fermentation by influencing the composition of microflora and fermentation metabolites, and consequently by contributing to both local and systemic effects in humans. Possibilities to enhance viability and promote growth of probiotic bacteria by non-digestible food components have been a subject to extensive scientific interest in the last ten years. Gut bacteria are known to degrade and ferment dietary fibre, producing metabolites, especially short-chain fatty acids. They also mediate a number of important consequences through their further metabolism in the liver. Current research is at quick steps increasing our understanding about the interactions between gut microbes and bioactive dietary phenolics. Absorption and metabolism of phenolic compounds occurs along the digestive tract. Those compounds not absorbed or converted earlier enter the colon, and may be converted to metabolites concomitantly with carbohydrate fermentation. All the colonic metabolites can have effects on the epithelium at the site of conversion, and also affect the colonic flora locally. When absorbed the metabolites are found in plasma and urine and can have systemic health effects. The health effects of phenolic compounds have been studied extensively, but those of the metabolites are poorly known. As strong antimicrobial agents the phenolics might also have unpredictable effects on the composition of the intestinal flora.

An extensive study on the effects of blanching/freezing and long-term freezer storage on various bioactive compounds of more than 20 commonly used vegetables was performed. Effects were strongly plant species-dependent. Contents of dietary fibre components either were not affected or increased slightly. Minerals in general were also stable, but some losses of soluble minerals by leaching were observed. Phenolic antioxidants and vitamins were clearly more sensitive. Significant losses (20-30%) of antioxidant activity and total phenolics were detected in many vegetables. A qualitative HPLC profiling method for phenolic antioxidants was developed which proved to be very useful when evaluating the complex behaviour of phenolics during food processing. Up to one-third of vitamin C contents were lost during blanching, and further slight losses were detected during storage. Folic acid turned out to be very sensitive to blanching, with more than half of the vitamin being lost, but was stable during freezer storage. Carotenoids and sterols were not affected by blanching or freezer storage. The usefulness of the applied screening methods for evaluation of the effects of processing on vegetables is shown.  2003 Society of Chemical Industry

The plant sterol contents of the most important vegetables, fruits and berries available in Finland were determined by capillary gas chromatography. The sample preparation procedure included both acid and alkaline hydrolysis to liberate sterols from their conjugates. The plant sterol contents of fresh vegetables ranged from 51 to 370 mg kg−1 fresh weight (fw) in samples obtained from retail sale. The highest contents (>300 mg kg−1) were measured in broccoli, Brussels sprouts, cauliflower and dill and the lowest (51 mg kg−1) in potato. The range of sterol contents on a dry weight (dw) basis was high, 246–4100 mg kg−1 dw. Considerable variation was also observed when individual samples of some vegetables were compared. Sitosterol was the main sterol (proportion 43–86%) in all vegetables except cucumber and spinach, in which Δ7-sterols dominated. The total sterol contents were in the range 116–228 mg kg−1 fw in all fresh fruits except avocado, which contained more sterols, 752 mg kg−1 fw. In fresh berries the corresponding range was 60–279 m kg−1 fw. The wild berries lingonberry and blueberry were better plant sterol sources than the cultivated berries blackcurrant, redcurrant and strawberry. In fruits and berries the proportion of sitosterol ranged from 61–93% total sterols. On the basis of the results, the contribution of vegetables, fruits and berries to the total average daily plant sterol intake was estimated to be ca 60 mg. © 2003 Society of Chemical Industry

By using a batch in vitro anaerobic fecal fermentation model, we have shown that the fecal microflora can rapidly deconjugate rutin, isoquercitrin, and a mixture of quercetin glucuronides. High levels of beta,D-glucosidase, alpha,L-rhamnosidase, and beta,D-glucuronidase were present. Rutin underwent deglycosylation, ring fission, and dehydroxylation. The main metabolite, 3,4-dihydroxyphenylacetic acid, appeared rapidly (2 h) and was dehydroxylated to 3-hydroxyphenylacetic acid within 8 h. The pattern of in vitro fermentation of rutin was not changed by changing the pH (6.0 or 6.9), fermentation scale (10 or 1000 mL), or donors of the inoculum. Hydroxyphenylacetic acids were not methylated by colon flora in vitro. The colonic microflora has enormous potential to transform flavonoids into lower molecular weight phenolics, and these might have protective biological activities in the colon. The site of absorption of flavonoids and the form in which they are absorbed are critical for determining their metabolic pathway and consequent biological activities in vivo.

Microbial reactions in the gut have an essential role not only in gut health, but in general human health. The gut is the site of active fermentation of non-digestible diet components, as well as bioconversions and absorption of plant-derived compounds, such as phenolics. When developing nutritionally designed foods that promote health through gut microbial reactions, three different types of food ingredients can be used: living micro-organisms (probiotics), non-digestible carbohydrates (dietary fiber and prebiotics) and bioactive plant secondary metabolites (e.g. phenolics).

Scope: Urinary hippuric acid has been proposed as a biomarker for fruit, vegetable and polyphenol consumption. We assessed how serum hippuric acid changes after a bilberry-enriched diet (BB; high anthocyanin intake) and another berry diet including strawberries, raspberries and cloudberries (SRC; lower anthocyanin intake) and how these changes associate with insulin and glucose metabolism. Methods and results: Hippuric acid was measured with LC-QTOF-MS metabolite profiling analysis from fasting serum samples at baseline and after an 8-week intervention in 47 individuals with features of the metabolic syndrome who were randomized to either a BB diet (n = 15), a SRC diet (n = 20) or a control diet (n = 12). Fasting serum hippuric acid increased significantly (3.5-fold, p = 0.001) only in the BB group and correlated with changes in fasting plasma glucose concentration (r = -0.54, p

Bacteria use quorum sensing signalling in various functions, e.g. while forming biofilms, and inhibition of this signalling could be one way to control biofilm formation. The aim of this study was to evaluate the production of signalling molecules and its correlation with the biofilm formation capability of bacteria isolated from brewery filling process. A further aim was to study berry extracts and wood-derived terpenes for their possible quorum sensing inhibitory effects. Out of the twenty bacteria studied, five produced short-chain and five long-chain AHL (acyl homoserine lactone) signalling molecules when tested with the Chromobacterium violaceum CV026 reporter bacterium. Production of AI-2 (autoinducer-2) signalling molecules was detected from nine strains with the Vibrio harveyi BB170 bioassay. Over half of the strains produced biofilm in the microtitre plate assay, but the production of AHL and AI-2 signalling molecules and biofilm formation capability did not directly correlate with each other. Out of the 13 berry extracts and wood-derived terpenes screened, four compounds decreased AHL signalling without effect on growth. These were betulin, raspberry extract and two cloudberry extracts. The effect of these compounds on biofilm formation of the selected six bacterial strains varied. The phenolic extract of freeze-dried cloudberry fruit caused a statistically significant reduction of biofilm formation of Obesumbacterium proteus strain. Further experiments should aim at identifying the active compounds and revealing whether quorum sensing inhibition causes structural changes in the biofilms formed.

The impact of bioprocessing on lingonberry flavour was studied by sensory evaluation and chemical analysis (organic acids, mannitol, phenolic compounds, sugars and volatile compounds). Bioprocessing of lingonberries with enzymes, lactic acid bacteria (LAB) or yeast, or their combination (excluding pure LAB fermentation) affected their perceived flavour and chemical composition. Sweetness was associated especially with enzyme treatment but also with enzyme+LAB treatment. Yeast fermentation caused significant changes in volatile aroma compounds and perceived flavour, whereas minor changes were detected in LAB or enzyme-treated berries. Increased concentration of organic acids, ethanol and some phenolic acids correlated with perceived fermented odour/flavour in yeast fermentations, in which increase in benzoic acid level was significant. In enzymatic treatment decreasing anthocyanins correlated well with decreased perceived colour intensity. Enzyme treatment is a potential tool to decrease naturally acidic flavour of lingonberry. Fermentation, especially with yeast, could be an interesting new approach to increase the content of natural preservatives, such as antimicrobial benzoic acid.

The availability and quality of wild berry material is strongly affected by seasonal variations, human resources, and both chemical and biological pollutants. Here we describe for the first time the industrial scale biotechnological production of cloudberry (Rubus chamaemorus) cells of consistent quality and defined chemical composition. Callus was initiated from sterile cuts of the wild cloudberry leaves. Bright yellow, soft callus of uniform quality was selected by regular subculturing, and a stable line successfully used for suspension culture was obtained within 18 months. The cultivation process of the cell culture was initiated in 250 mL shake flasks and stepwise expanded to a stirred tank bioreactor of 300 L working volume. Each growth period in flasks and fed-batch cultures in bioreactors was 10 ± 3 days. Viability of the cultures was approximately 90% throughout the cultivation processes. The 300 L culture was harvested by pressure filtration and the biomass was freeze-dried. The 300 L yields of fresh cells and freeze-dried material were 19 and 2 kg, respectively. The unusual phenolic profile of cloudberry cells including flavanols, as well as their fatty acid composition with a high proportion of α-linolenic acid and high protein content, make them a unique and interesting alternative for industrial applications for various industrial fields.

Ellagitannins are polyphenols abundant in strawberries, raspberries, and cloudberries. The effects of a mixture of these berries were studied in a randomized controlled trial with subjects having symptoms of metabolic syndrome. The study focused on serum lipid profiles, gut microbiota, and ellagitannin metabolites. The results indicate that bioavailability of ellagitannins appears to be dependent on the composition of gut microbiota.

Scope: Low‐grade inflammation is a hallmark of cardiometabolic risk. Bilberries (Vaccinium myrtillus) are rich in polyphenols with potential anti‐inflammatory properties. We studied the impact of bilberries on inflammation and gene expression profile in peripheral blood mononuclear cells in subjects with metabolic syndrome. Methods and results: In randomized, controlled dietary intervention, the participants consumed either a diet rich in bilberries (n = 15) or a control diet (n = 12). The bilberry group consumed daily an equivalent dose of 400 g fresh bilberries, while the control group maintained their habitual diet. No differences were found between the groups in body weight, glucose, or lipid metabolism, but bilberry supplementation tended to decrease serum high‐sensitivity C‐reactive protein, IL‐6, IL‐12, and LPS concentrations. An inflammation score was significantly different between the groups (p = 0.024). In transcriptomics analyses (three participants with improved oral glucose tolerance test in the bilberry group), Toll‐like receptor signaling, cytoplasmic ribosomal proteins, and B‐cell receptor signaling pathways were differently regulated. QPCR analyses (n = 13 and 11 in the bilberry and control groups, respectively) showed decreased expression of MMD and CCR2 transcripts associated with monocyte and macrophage function associated genes. Conclusion: Regular bilberry consumption may reduce low‐grade inflammation indicating decreased cardiometabolic risk in the long term.

European, small-fruited cranberries (Vaccinium microcarpon) and lingonberries (Vaccinium vitis-idaea) were characterized for their phenolic compounds and tested for antioxidant, antimicrobial, antiadhesive, and antiinflammatory effects. The main phenolic compounds in both lingonberries and cranberries were proanthocyanidins comprising 63−71% of the total phenolic content, but anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and flavonols were also found. Proanthocyanidins are polymeric phenolic compounds consisting mainly of catechin, epicatechin, gallocatechin, and epigallocatechin units. In the present study, proanthocyanidins were divided into three groups: dimers and trimers, oligomers (mDP 4−10), and polymers (mDP > 10). Catechin, epicatechin, A-type dimers and trimers were found to be the terminal units of isolated proanthocyanidin fractions. Inhibitions of lipid oxidation in liposomes were over 70% and in emulsions over 85%, and in most cases the oligomeric or polymeric fraction was the most effective. Polymeric proanthocyanidin extracts of lingonberries and cranberries were strongly antimicrobial against Staphylococcus aureus, whereas they had no effect on other bacterial strains such as Salmonella enterica sv. Typhimurium, Lactobacillus rhamnosus and Escherichia coli. Polymeric fraction of cranberries and oligomeric fractions of both lingonberries and cranberries showed an inhibitory effect on hemagglutination of E. coli, which expresses the M hemagglutin. Cranberry phenolic extract inhibited LPS-induced NO production in a dose-dependent manner, but it had no major effect on iNOS of COX-2 expression. At a concentration of 100 μg/mL cranberry phenolic extract inhibited LPS-induced IL-6, IL-1β and TNF-α production. Lingonberry phenolics had no significant effect on IL-1β production but inhibited IL-6 and TNF-α production at a concentration of 100 μg/mL similarly to cranberry phenolic extract. In conclusion the phenolics, notably proanthocyanidins (oligomers and polymers), in both lingonberries and cranberries exert multiple bioactivities that may be exploited in food development.

Background and aim: Cloudberries are a rich source of phenolics, mainly ellagitannins (ETs) and ellagic acid (EA), which have recently been associated with human health benefits. Our aim is to induce changes in cloudberry phenolic composition based on microbial fermentations with different lactic acid bacteria (LAB) and evaluate the antimicrobial and antioxidant properties. Materials and Methods: Cloudberry fermentations were carried out with different strains such as, Lactobacillus plantarum, Lactococcus lactis, Leuconostoc citreum and Pediococcus pentosaceus, during 7 and 14 days. The changes produced in the phenolic profiles were analyzed by HPLC-DAD. Additionally, we also have examined the antimicrobial activity of these berry fermentations against Staphylococcus aureus and Escherichia coli and yeast, Candida albicans and antioxidant activity by DPPH assay. Results: HPLC-DAD analysis showed changes in the phenolic composition of fermented berry samples. All LAB used increased the EA content up to 5-fold when compared to the starting point. In addition, an EA-conjugate was detected after seven days of fermentation and it increased after fourteen days (2-4 mg/g dry-weight). In contrast, ETs present in cloudberry extracts were decreased. These changes could be explained by the hydrolysis of ETs during fermentation, which liberated EA. Other phenolic compounds, as quercetin-3-O-hexoside (0.3-0.4 mg/g dry-weight) and benzoic acid (4.1-6.8 mg/g dry-weight) were stable after 14 days of fermentation with Lb. plantarum, Lc. citreum and P. pentosaceus. The highest amount of EA was observed when cloudberry was fermented with P. pentosaceus (28 mg/g dry-weight). This fermentation, improved in EA content, also showed good antimicrobial activity against S. aureus and E. coli but no activity was seen against C. albicans. In addition, increasing trend in DPPH radical scavenging activity was detected during LAB fermentations. Conclusions: These results demonstrated that EA-enriched cloudberry material obtained after LAB fermentations has an added-value for further use in functional food products and drug development, which could exert more beneficial effects.

We have isolated the birch homologue (BP8) for the carrot embryogenic gene DC8 by heterologous hybridization. The birch BP8 gene encodes a putative protein of 53 kDa, showing 52% sequence identity with the DC8 gene at the amino acid level. The putative BP8 protein contains 20 repeats of 11 amino acids and thus belongs to the group of LEA proteins isolated from such plants as carrot, cotton and wheat. Northern hybridization of mRNA isolated from birch cells representing different stages of somatic embryogenesis and non-embryogenetic material with a PB8 probe gave no signals, suggesting a low expression level of the BP8 gene.

Berries contain a large variety of different phenolic compounds such as anthocyanins, flavonols, tannins, and phenolic acids. Due to variation in the nature and content of the phenolic compounds, the antioxidant effect and other bioactivities of berry phenolics are strongly dependent on the berry raw material as the activities differ between the different phenolic constituents. In the present study, wild rowanberries (Sorbus aucuparia) and four cultivated sweet rowanberries, Burka, Granatnaja, Titan, and Zoltaja, were characterized for their phenolic composition and screened for antioxidant, antimicrobial, and antiadhesive activities. The HPLC and LC-MS analyses of phenolic composition revealed that the main phenolic constituents were caffeoylquinic acids, varying from 56 to 80% total phenolics. The cultivated species contained less caffeoylquinic acids and more anthocyanins (up to 28.5%). The phenolics derived from wild rowanberries were significantly effective at inhibiting lipid oxidation both in liposomes and in emulsions, especially when assessed by inhibition of the formation of hexanal (86−97% inhibition depending on concentration). The increase in anthocyanin content in the cultivated species did not result in significantly increased antioxidant activity. Both wild and cultivated rowanberry phenolics exhibited a bacteriostatic effect toward Staphylococcus aureus. In addition, the phenolic extract from Zoltaja was weakly inhibitory toward Salmonella sv. Typhimurium, whereas both Zoltaja- and Granatnaja-derived phenolics retarded Escherichia coli growth. The phenolic extracts of wild rowanberries and Burka showed an inhibitory effect on hemagglutination of E. coli HB101 (pRR7), which expresses the M hemagglutinin. It can be concluded that cultivation of rowanberries resulted in increased anthocyanin content, but this did not diminish their bioactivity in comparison to wild rowanberries rich in caffeoylquinic acids.

The effects of nine cell wall-degrading enzymes on the antimicrobial and antioxidant activities of bilberry were studied. Antimicrobial activity was measured using the human pathogens Salmonella enterica sv. Typhimurium and Staphylococcus aureus as test strains. Enzyme treatments liberated phenolics from the cell wall matrix, which clearly increased the antimicrobial activity of berry juices, press cakes, and berry mashes on the basis of plate counts. Antibacterial effects were stronger against Salmonella than against Staphylococcus bacteria. In general, the increase in activity measured as colony-forming units per milliliter was 3–5 logarithmic units against Salmonella and 1–2 units against Staphylococcus bacteria. Increase in antimicrobial activity was observed only in acidic conditions, which is also the natural environment in various berry products, such as juices. The activity profile of the pectinase preparation affected the chemistry of the phenolics due to the presence of deglycosylating activities in some preparations. The difference in phenolic profiles was reflected in the antimicrobial effects. Bilberry mashes treated with Pectinex Ultra SP-L, Pectinex 3 XL, and Pectinex BE XXL were most efficient against Salmonella bacteria, whereas mashes treated with Pectinex Smash, Pectinex BE 3-L, and Biopectinase CCM showed the strongest antimicrobial activity against Staphylococcus bacteria. Due to the liberation of phenolics from the cell wall matrix the antioxidant activity measured as radical scavenging activity was also increased on average about 30% by the enzymatic treatments. The highest increase in phenolic compounds was about 40%. Highest increases in anthocyanins and in antioxidant activity were observed in berry mash treated with Pectinex Smash XXL enzyme, and the lowest increase was observed after treatment with Pectinex BE 3-L. Enzyme-assisted processing is traditionally used to improve berry and fruit juice yields. However, enzymatic treatments also have an impact on the functional properties of the products. The increased liberation of phenolics from the cell wall matrix can prolong the shelf life of berry products by limiting the growth of contaminants during processing or storage. The increased amount of phenolic compounds may also have a positive effect on gut well-being.

Berry fruits are rich in phenolic compounds, such as flavonoids, phenolic acids, lignans and complex polymeric tannins, with wide variation in their contents depending on the plant species and environmental factors. The main phenolics in strawberry fruits are anthocyanins and ellagitannins. We have shown earlier that ellagitannins possess strong antimicrobial properties against human gastrointestinal pathogens. As an alternative to use of strawberry fruits, plant leaves and cell cultures are interesting choice for production of strawberry phenolics, as well as other, potentially novel secondary metabolites with interesting biological effects. As far as we know, strawberry cell cultures have not been used for production of berry and plant phenolics earlier. In this study, sterile in vitro strawberry plants were germinated from sterilized seeds. Cuts of the in vitro leaves were treated with plant growth hormones for production of callus, and the most productive calli were used for establishment of strawberry cell cultures. Analysis of phenolic extracts of strawberry fruits, leaves and cell cultures were performed using HPLC-DAD and LC-MS, and comparison of phenolic compound patterns of in vivo strawberry fruits and leaves to those of in vitro leaves and cell cultures revealed interesting differences. Also antimicrobial activities against selected human pathogenic bacteria and anti-oxidative activities, measured as radical scavenging activity, varied depending on the origin of the material of phenolic extract. These results showed that strawberry leaves are interesting and rich sources of bioactive phenolic compounds.

Antimicrobial activity and mechanisms of phenolic extracts of 12 Nordic berries were studied against selected human pathogenic microbes. The most sensitive bacteria on berry phenolics were Helicobacter pylori and Bacillus cereus. Campylobacter jejuni and Candida albicans were inhibited only with phenolic extracts of cloudberry, raspberry, and strawberry, which all were rich in ellagitannins. Cloudberry extract gave strong microbicidic effects on the basis of plate count with all studied strains. However, fluorescence staining of liquid cultures of virulent Salmonella showed viable cells not detectable by plate count adhering to cloudberry extract, whereas Staphylococcus aureus cells adhered to berry extracts were dead on the basis of their fluorescence and plate count. Phenolic extracts of cloudberry and raspberry disintegrated the outer membrane of examined Salmonella strains as indicated by 1-N-phenylnaphthylamine (NPN) uptake increase and analysis of liberation of [14C]galactose- lipopolysaccharide. Gallic acid effectively permeabilized the tested Salmonella strains, and significant increase in the NPN uptake was recorded. The stability of berry phenolics and their antimicrobial activity in berries stored frozen for a year were examined using Escherichia coli and nonvirulent Salmonella enterica sv. Typhimurium. The amount of phenolic compounds decreased in all berries, but their antimicrobial activity was not influenced accordingly. Cloudberry, in particular, showed constantly strong antimicrobial activity during the storage.

Phenolic compounds present in berries selectively inhibit the growth of human gastrointestinal pathogens. Especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. Complex phenolic polymers, such as ellagitannins, are strong antibacterial agents present in cloudberry, raspberry and strawberry. Berry phenolics seem to affect the growth of different bacterial species with different mechanisms. Adherence of bacteria to epithelial surfaces is a prerequisite for colonization and infection of many pathogens. Antimicrobial activity of berries may also be related to anti-adherence activity of the berries. Utilization of enzymes in berry processing increases the amount of phenolics and antimicrobial activity of the berry products. Antimicrobial berry compounds are likely to have many important applications in the future as natural antimicrobial agents for food industry as well as for medicine.

R. PUUPPONEN-PIMIA¨ , L. NOHYNEK, S. HARTMANN-SCHMIDLIN, M. KAHKONEN, M. HEINONEN, K. MAATTA¨ -RIIHINEN AND K.-M. OKSMAN-CALDENTEY. 2005. Aims: To investigate the effects of berries and berry phenolics on pathogenic intestinal bacteria and to identify single phenolic compounds being responsible for antimicrobial activity. Methods and Results: Antimicrobial activity of eight Nordic berries and their phenolic extracts and purified phenolic fractions were measured against eight selected human pathogens. Pathogenic bacterial strains, both Gram- positive and Gram-negative, were selectively inhibited by bioactive berry compounds. Cloudberry and raspberry were the best inhibitors, and Staphylococcus and Salmonella the most sensitive bacteria. Phenolic compounds, especially ellagitannins, were strong inhibitory compounds against Staphylococcus bacteria. Salmonella bacteria were only partly inhibited by the berry phenolics, and most of the inhibition seemed to originate from other compounds, such as organic acids. Listeria strains were not affected by berry compounds, with the exception of cranberry. Phenolic compounds affect the bacteria in different mechanisms. Conclusions: Berries and their phenolics selectively inhibit the growth of human pathogenic bacteria. Significance and Impact of the Study: Antimicrobial properties of berries could be utilized in functional foods. Furthermore these compounds would be of high interest for further evaluation of their properties as natural antimicrobial agents for food and pharmaceutical industry.

Berries are traditionally an important part of the Nordic diet. About 50 different berries are grown in the northern region, and about half of them are edible. The most well-known and important wild berries are lingonberry, bilberry, raspberry, cloudberry, cranberry, buckthorn berry and crowberry. The annual crop of lingonberry and bilberry in Finland has been estimated to be as large as 500 million kg and 250 million kg, respectively. However, only a small part of this is harvested. Thus wild berries in the Nordic region form an enormous natural source, only a fractional part of which has been advantaged so far. In North America cranberry along with blueberry are two important native fruits which are commercially grown. Around 500 million tons are produced every year. Only 5% of the annual crop is harvested for fresh fruit and most of it is used for processing. Interest in the composition of berries has been intensified because of the increased awareness of their possible health effects. Berry fruits are rich sources of bioactive compounds, such as phenolics and organic acids, which have antimicrobial activities against harmful bacteria and human pathogens. Among different berries and berry phenolics, especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. These antimicrobial effects on different bacteria may also be species or strain dependent in character. Complex phenolic polymers, like ellagitannins, are strong antibacterial agents present in cloudberry and raspberry. Several mechanisms of action in the growth inhibition of bacteria are involved, such as destabilization of cytoplasmic membrane, permeabilization of plasma membrane, inhibition of extracellular microbial enzymes, direct actions on microbial metabolism and deprivation of the substrates required for microbial growth. Antimicrobial activity of berries may also be related to antiadherence of bacteria to epithelial cells, which is a prerequisite for colonization and infection of many pathogens. The antiadherence properties have so far been reported to cranberry phenolics. Berry juices are often very acidic due to high content of organic acids, and this may have an impact on the antimicrobial properties of the phenolics. Thus pH is a very important parameter when evaluating the antimicrobial activity of the berry compounds either in various food matrices or in the human body. Antimicrobial berry compounds may have important applications in the future in food industry as well as in medicine.

Anthocyanins are flavonoids which produce blue, purple red and intermediate colours in plants. They are present as glycosides with an anthocyanidin C6-C3-C6 skeleton, whose structure is dependent on pH. Anthocyanins are poorly detected from the biological fluids: plasma and urine. They may be poorly absorbed or they undergo changes in their structure. Nevertheless, large amounts of the ingested compounds are likely to enter the colon either within the matrix of the dietary source or through enterohepatic circulation. In vitro and in vivo studies have shown that colonic bacteria transform various flavonoids to smaller phenolic acids. However, there is very little information on bacterial transformations of anthocyanins. Aims of the study were to find out the release and changes of anthocyanins in the in vitro upper intestinal model and their bacterial metabolism in the colon model. Frozen berries, bilberry (Vaccinium myrtillus) and red raspberry (Rebus idaeus, v. Ottawa), were subjected to physiological conditions in the presence and absence of active or heat-inactivated alimentary enzymes (salivary amylase, pepsin, pancreatin and mucin) in successive stages of mouth, stomach and duodenum. Changes in stomach and duodenum were compared for their anthocyanin response by HPLC detected at 520 nm. Bacterial transformations of pure anthocyanins (cyanidin-3-glucoside and -rutinoside) isolated from red blum (Prunus domestica L.) and red grapes (Vitis vinifera L.) were studied in an in vitro colon model using human faecal microbiota as an inoculum. Metabolites were analysed and characterized by HPLC-DAS and LC-MS. They were identified by comparing their characteristics with those of available standards, and semi-quantified using the amount of substrate analysed from samples at initial timepoint. Anthocyanins gave a good response as flavylium cations in 520 nm in acidic conditions mimicking stomach and the detection was decreased dramatically in neutral to mildly basic conditions of duodenum indicating opening of the flavylium cation to quinoidal base. In the colon model in vitro cyanidin-3-rutinoside and cyanidin-3-glucoside were deglycosylated and formation of three low molecular weight metabolites were shown. The major metabolite at earlier time points was identified as protocatechuic acid. Furthermore, reconjugation of the aglycone with other groups, non-typical for dietary anthocyanins, was evident at the later timepoints. In conclusion, anthocyanins are poorly detected due to their pH dependent structural characteristics and their bioavailability is difficult to define on the basis of detection of flavylium cations only. Also, smaller molecular weight metabolites are formed due to bacterial actions in the colon, which involve the cleavage of glycosidic linkages, breakdown of the anthocyanidin heterocycle and reconjugation of the aglycone. Information about the health effects of the bacterial metabolites in general is scarce and therefore research directed to this area is necessary.

In this work antimicrobial activity of eight Finnish berries and their phenolic extracts were measured against selected Gram-positive and Gram-negative human pathogens. The results showed that berry compounds selectively inhibit the growth of pathogenic bacterial species, specially Salmonella and Staphylococcus strains, and cloudberry and raspberry were the best inhibitors. In general, berry compounds did not affect the growth of probiotic Lactobacillus rhamnosus strain and of Listeria strains. The only exception was cranberry, which inhibited the growth of Listeria bacteria. Introduction Berries are good sources of plant phenolics which besides their other health-inducing effects have been found to possess antimicrobial activities. Our previous studies showed that phenolic berry extracts especially inhibited the growth of Gram-negative but not Gram-positive bacteria such as Lactobacillus. Especially cloudberry, raspberry and strawberry extracts proved to be strong inhibitors of the avirulent Salmonella (I ). Materials and methods Bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), cranberry (Vaccinium oxycoccus), raspberry (Rubus idaeus, var. Ottawa), cloudberry (Rubus chamaemorus), strawberry (Fragaria ananassa Seaga Sengana), blackcurrant (Rites nigrum, var. Ojeby) and sea buckthorn berry (Hippophae rhamnoides), were used in the study. For antimicrobial studies berries were freeze-dried and ground to fine powder. Phenolics were extracted from the berries by aqueous 70% acetone (2). Antimicrobial activity of freeze-dried grounded berries (2 or 10 mg/ml) and phenolic berry extracts (1 or 5 mg/ml) was analysed by determining the bacterial growth curves in liquid cultures (I). The bacterial strains used were Listeria monocytogenes VTT E-991205, L. innocua VTT E-981011, Salmonella enterica ser. Typhimurium VTT E-981151, S. enterica ser. Infantis VTT E-97738, Staphylococcus aureus VTT E-70045 and Lactobacillus rhamnosus VTT E-96666 (ATCC 53103). Results discussion Salmonella strains were inhibited by all the berries. Cloudberry, raspberry, strawberry and bilberry extracts inhibited the growth during the first 12 h incubation. However, during the next 12 h the number of viable cells started to increase. Cloudberry extract was the best inhibitor showing strong antimicrobial effects. Slaphylococcus strains were strongly inhibited by all the berries and berry extracts. The number of viable cells did not increase at the end of cultivation. The tested Listeria or Lactobacillus strains were not sensitive to berries or berry extracts, with the exception of cranberry, which showed inhibitory effects against Listeria bacteria (Figure 1). The results showed that antimicrobial properties of the berry compounds aren't restricted to the avirulent Salmonella but inhibited also the virulent strains. The inhibition of the Staphylococcus aureus suggessted that also the structure of Gram-positive bacteria is sensitive to the antimicrobial compounds of the berries. Bioactive berry compounds seem to inhibit the growth of pathogenic bacteria with several mechanisms. The difference in the antimicrobial properties of the berries and the berry extracts also suggested that other bioactive compounds are involved in the cell growth inhibition. In the future, the most interesting berry extracts will be fractionated with the aim of identifying the antimicrobially active components. In addition the mechanism of action against gastrointestinal bacteria, especially intestinal pathogens, will be extensively studied. The results will be utilised in functional food development and in pharmaceutical applications.

Berries are good sources of phenolic compounds, which often act as defence compounds in plants. In humans plant phenolics besides their other health-inducing effects have been found to possess antimicrobial activities. Our previous studies showed that phenolic berry extracts especially inhibited the growth of Gram-negative but not Gram-positive bacteria such as Lactobacillus. Especially cloudberry, raspberry and strawberry extracts proved to be strong inhibitors of the avirulent Salmonella (1). Materials and Methods Bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), cranberry (Vaccinium oxycoccus), raspberry (Rubus idaeus, var. Ottawa), cloudberry (Rubus chamaemorus), strawberry (Fragaria ananassa Senga Sengana), blackcurrant (Ribes nigrum, var. Öjeby) and sea buckthorn berry (Hippophae rhamnoides), were used in the study. For antimicrobial studies berries were freeze-dried and ground to fine powder. Phenolics were extracted from the berries by aqueous 70% acetone (2). Antimicrobial activity of freeze-dried grounded berries (2 or 10 mg/ml) and phenolic berry extracts (1 or 5 mg/ml) was analysed by determining the bacterial growth curves in liquid cultures (1). The bacterial strains used were Listeria monocytogenes VTT E-991205, L. innocua VTT E-981011, Salmonella enterica ser. Typhimurium VTT E-981151, S. enterica ser. Infantis VTT E-97738, Staphylococcus aureus VTT E-70045 and Lactobacillus rhamnosus VTT E-96666 (ATCC 53103). Results Salmonella strains were inhibited by all the berries. Cloudberry, raspberry, strawberry and bilberry extracts inhibited the growth during the first 12 h incubation. However, during the next 12 h the number of viable cells started to increase. Cloudberry extract was the best inhibitor showing strong antimicrobial effects. Staphylococcus strains were strongly inhibited by all the berries and berry extracts. The number of viable cells did not increase at the end of cultivation. The tested Listeria or Lactobacillus strains were not sensitive to berries or berry extracts, with the exception of cranberry, which showed inhibitory effects against Listeria bacteria. Conclusions The results showed that antimicrobial properties of the berry compounds aren't restricted to the avirulent Salmonella but inhibited also the virulent strains. The inhibition of the Staphylococcus aureus suggested that also the structure of Gram-positive bacteria is sensitive to the antimicrobial compounds of the berries. Bioactive berry compounds seem to inhibit the growth of pathogenic bacteria with several mechanisms. The difference in the antimicrobial properties of the berries and the berry extracts also suggested that other bioactive compounds are involved in the cell growth inhibition. In the future, the most interesting berry extracts will be fractionated with the aim of identifying the antimicrobially active components. In addition the mechanism of action against gastrointestinal bacteria, especially intestinal pathogens, will be extensively studied. The results will be utilised in functional food development and in pharmaceutical applications.

The antioxidant activities of the methanol extracts of selected varieties and parts of garlic and onion were determined by two methods: inhibition of lipid peroxidation induced by tert-butyl hydroperoxide in isolated rat hepatocytes and scavenging activity against diphenylpicrylhydrazyl radical. The total phenolics and the main flavonoids of the hydrolysed onion and garlic samples were also analysed. The antioxidant activities obtained by the two methods were compared. Both methods gave similar antioxidant activities for pure compounds and Allium extracts. However, the radical scavenging method had many benefits compared to the lipid peroxidation method, being easier, cheaper, more specific and reproducible. The radical scavenging activities also correlated positively with the total phenolics of the extracts. Onions had clearly higher radical scavenging activities than garlic, red onion being more active than yellow onion. The skin extracts of onion possessed the highest activities.

Aims: To investigate the antimicrobial properties of phenolic compounds present in Finnish berries against probiotic bacteria and other intestinal bacteria, including pathogenic species.Methods and Results: Antimicrobial activity of pure phenolic compounds representing flavonoids and phenolic acids, and eight extracts from common Finnish berries, was measured against selected Gram‐positive and Gram‐negative bacterial species, including probiotic bacteria and the intestinal pathogen Salmonella. Antimicrobial activity was screened by an agar diffusion method and bacterial growth was measured in liquid culture as a more accurate assay. Myricetin inhibited the growth of all lactic acid bacteria derived from the human gastrointestinal tract flora but it did not affect the Salmonella strain. In general, berry extracts inhibited the growth of Gram‐negative but not Gram‐positive bacteria. These variations may reflect differences in cell surface structures between Gram‐negative and Gram‐positive bacteria. Cloudberry, raspberry and strawberry extracts were strong inhibitors of Salmonella. Sea buckthorn berry and blackcurrant showed the least activity against Gram‐negative bacteria.Conclusions: Different bacterial species exhibit different sensitivities towards phenolics.Significance and Impact of the Study: These properties can be utilized in functional food development and in food preservative purposes.