Total phenolics,resveratrol content and antioxidant activity of seeds and calluses of pinto peanut (<Emphasis Type="Italic">Arachis pintoi</Emphasis> Krapov. &amp; W.C. Greg.)

Arachis pintoi is a peanut species native to Brazil, which is cultivated in many countries for animal forage, soil cover, landscaping, and recovery of degraded areas. Tissue culture studies for this species have been focused in plant production, whereas works on in vitro secondary metabolites production are scarce. The goal of the present work was to establish callus cultures from different seed explants of A. pintoi, aiming at evaluating the potential for metabolites production and antioxidant activity. Embryonic axes, leaflets, and cotyledons were cultured on solidified MS medium supplemented with picloram (PIC), 2,4-dichlorophenoxyacetic acid (2,4-D), thidiazuron (TDZ) or different combinations of 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA), under light or dark conditions. Friable calluses with a high biomass (4.3?±?0.3 g FW per callus) were obtained from embryonic leaflets cultured on medium supplemented with 17.6 µM BA plus 5.4 µM NAA, in the dark. Cotyledons and embryonic axes cultured in the presence of 4.4 µM BA combined with 10.8 µM NAA formed heterogeneous calluses with a compact base and a large friable surface. Trans-resveratrol and other stilbenes that were not found in seeds were detected in callus extracts, especially those originated from cotyledons, although these materials showed lower total phenolic contents (TPC) when compared with seeds with and without testa, as well as cotyledons. Extracts from seeds with testa and from calluses derived from cotyledons and embryonic axes showed the highest EC₅₀ in DPPH assays. No correlation between TPC, trans-resveratrol and antioxidant activity was observed.     

Fenomeni di Inattivazione e di Riattivazione Enzimatica in Endospermi di semi di Ricino

Abstract

Inactivation and riactivation of enzymes in endosperms of castor bean seeds. — On the basis of previous results, the possibility has been investigated of the reversible interconversion of active and inactive form of enzymes in castor bean seeds, during their development.

The results described here indicate that:

1. the activity of some glycolytic enzymes increases greatly (81% and 400% increase of, respectively, Gl-6-P-dehydrogenase and aldolase) upon incubation of dry seeds for few hours at 4 °C.

2. The decrease of enzyme activity upon dehydration of seeds and the increase during the subsequent imbibition can be shown reproducibly.

3. This same observation is made for oxygen uptake.

These results are interpreted to indicate the reversible inactivation of enzymes caused by dehydration of seeds.     

Effect of Weak Sinusoidal Magnetic Field on Germination and Yield of Cotton (Gossypium spp.)

This paper presents the results of a preliminary study on the effects of sinusoidal magnetic fields on percentage germination, growth, and yield of cotton (Gossypium species). The paper covers a brief account of the experimental setup, protocol, and the essential parameters employed. The study was carried out using var.spch‐1 cotton seeds having three different germination capacities (Type 1—31%, Type 2—49%, Type 3—64%). The seeds were subjected to magnetic fields with nine different frequencies and intensities as follows: A. 1 Hz, 100 nT; B. 1 Hz, 1500 nT; C. 1 Hz, 4000 nT; D. 10 Hz, 100 nT; E. 10 Hz, 1500 nT; F. 10 Hz, 4000 nT; G. 100 Hz, 100 nT; H. 100 Hz, 1500 nT; I. 100 Hz, 4000 nT. In Type 3 cotton seeds exposed to 10 Hz, 100 nT fields, the yield was 75.3% higher than that of control, and in Type 2 cotton seeds exposed to 100 Hz, 1500 nT fields, the yield was 85.2% higher than that of control.

The experiment leads to two major clear‐cut findings:

1. Pre‐sowing exposure of seeds to extremely low frequency (ELF) magnetic fields catalyzes certain varieties of cotton to yield as much as double the crop output yielded by unexposed controls.

2. The yield is strongly frequency dependent, i.e., the cotton varieties show outstanding responses only at specific frequencies.

     

Human milk and mucosal lacto- and galacto-<Emphasis Type="Italic">N</Emphasis>-biose synthesis by transgalactosylation and their prebiotic potential in <Emphasis Type="Italic">Lactobacillus</Emphasis> species

Lacto-N-biose (LNB) and galacto-N-biose (GNB) are major building blocks of free oligosaccharides and glycan moieties of glyco-complexes present in human milk and gastrointestinal mucosa. We have previously characterized the phospho-β-galactosidase GnbG from Lactobacillus casei BL23 that is involved in the metabolism of LNB and GNB. GnbG has been used here in transglycosylation reactions, and it showed the production of LNB and GNB with N-acetylglucosamine and N-acetylgalactosamine as acceptors, respectively. The reaction kinetics demonstrated that GnbG can convert 69 ± 4 and 71 ± 1 % of o-nitrophenyl-β-d-galactopyranoside into LNB and GNB, respectively. Those reactions were performed in a semi-preparative scale, and the synthesized disaccharides were purified. The maximum yield obtained for LNB was 10.7 ± 0.2 g/l and for GNB was 10.8 ± 0.3 g/l. NMR spectroscopy confirmed the molecular structures of both carbohydrates and the absence of reaction byproducts, which also supports that GnbG is specific for β1,3-glycosidic linkages. The purified sugars were subsequently tested for their potential prebiotic properties using Lactobacillus species. The results showed that LNB and GNB were fermented by the tested strains of L. casei, Lactobacillus rhamnosus (except L. rhamnosus strain ATCC 53103), Lactobacillus zeae, Lactobacillus gasseri, and Lactobacillus johnsonii. DNA hybridization experiments suggested that the metabolism of those disaccharides in 9 out of 10 L. casei strains, all L. rhamnosus strains and all L. zeae strains tested relies upon a phospho-β-galactosidase homologous to GnbG. The results presented here support the putative role of human milk oligosaccharides for selective enrichment of beneficial intestinal microbiota in breast-fed infants.     

Efficient bioconversion of <Emphasis Type="SmallCaps">l</Emphasis>-glutamate to γ-aminobutyric acid by <Emphasis Type="Italic">Lactobacillus brevis</Emphasis> resting cells

This work investigated the efficient bioconversion process of l-glutamate to GABA by Lactobacillus brevis TCCC 13007 resting cells. The optimal bioconversion system was composed of 50 g/L 48 h cultivated wet resting cells, 0.1 mM pyridoxal phosphate in glutamate-containing 0.6 M citrate buffer (pH 4.5) and performed at 45 °C and 180 rpm. By 10 h bioconversion at the ratio of 80 g/L l-glutamic acid to 240 g/L monosodium glutamate, the final titer of GABA reached 201.18 g/L at the molar bioconversion ratio of 99.4 %. This process presents a potential for industrial and commercial applications and also offers a promising feasibility of continuous GABA production coupled with fermentation. Besides, the built kinetics model revealed that the optimum operating conditions were 45 °C and pH 4.5, and the bioconversion kinetics at low ranges of substrate concentration (0 < S < 80 g/L) was assumed to follow the classical Michaelis–Menten equation.     

Enhancement of Nisin Production by <Emphasis Type="Italic">Lactococcus lactis</Emphasis> subsp. <Emphasis Type="Italic">lactis</Emphasis>

Lactococcus lactis subsp lactis BSA (L. lactis BSA) was isolated from a commercial fermented product (BSA Food Ingredients, Montreal, Canada) containing mixed bacteria that are used as starter for food fermentation. In order to increase the bacteriocin production by L. lactis BSA, different fermentation conditions were conducted. They included different volumetric combinations of two culture media (the Man, Rogosa and Sharpe (MRS) broth and skim milk), agitation level (0 and 100 rpm) and concentration of commercial nisin (0, 0.15, and 0.30 µg/ml) added into culture media as stimulant agent for nisin production. During fermentation, samples were collected and used for antibacterial evaluation against Lactobacillus sakei using agar diffusion assay. Results showed that medium containing 50 % MRS broth and 50 % skim milk gave better antibacterial activity as compared to other medium formulations. Agitation (100 rpm) did not improve nisin production by L. lactis BSA. Adding 0.15 µg/ml of nisin into the medium-containing 50 % MRS broth and 50 % skim milk caused the highest nisin activity of 18,820 AU/ml as compared to other medium formulations. This activity was 4 and ~3 times higher than medium containing 100 % MRS broth without added nisin (~4700 AU/ml) and 100 % MRS broth with 0.15 µg/ml of added nisin (~6650 AU/ml), respectively.     

Treatability of cheese whey for single-cell protein production in nonsterile systems: Part II. The application of aerobic sequencing batch reactor (aerobic SBR) to produce high biomass of Dioszegia sp. TISTR 5792

This study aimed to investigate the efficiency of an aerobic sequencing batch reactor (aerobic SBR) in a nonsterile system using the application of an experimental design via central composite design (CCD). The acidic whey obtained from lactic acid fermentation by immobilized Lactobacillus plantarum sp. TISTR 2265 was fed into the bioreactor of the aerobic SBR in an appropriate ratio between acidic whey and cheese whey to produce an acidic environment below 4.5 and then was used to support the growth of Dioszegia sp. TISTR 5792 by inhibiting bacterial contamination. At the optimal condition for a high yield of biomass production, the system was run with a hydraulic retention time (HRT) of 4 days, a solid retention time (SRT) of 8.22 days, and an acidic whey concentration of 80% feeding. The chemical oxygen demand (COD) decreased from 25,230 mg/L to 6,928 mg/L, which represented a COD removal of 72.15%. The yield of biomass production and lactose utilization by Dioszegia sp. TISTR 5792 were 13.14 g/L and 33.36%, respectively, with a long run of up to 180 cycles and the pH values of effluent were rose up to 8.32 without any pH adjustment.     

Purification and Characterization of Antioxidative Peptides Derived From Fermented Milk (<Emphasis Type="Italic">Lassi</Emphasis>) by Lactic Cultures

Fermentation of milk with lactic acid bacteria is the most suitable approach to enrich the bioactive peptides in fermented milk products. So in the present study, two sets of fermented milk (lassi) were prepared. The one lassi was prepared using standard Dahi culture NCDC-167(BD₄) and the other one was made with the same Dahi culture combined with Lactobacillus acidophilus NCDC-15 as an adjunct culture. The preparation steps i.e. preheat treatment and incubation period were optimized by using response surface methodology to obtain maximum antioxidant activity. Lassi prepared with adjunct culture using optimized conditions showed an antioxidant activity of 0.66?±?0.01 µM Trolox/mg protein which was significantly higher than that control (0.22?±?0.01 µM Trolox/mg protein). Out of 59 peptide fragments of β casein fermented by L. acidophilus and 24 peptides from control have been identified by LC–MS/MS. Most of the peptides showed the antioxidant activity. The therapeutic potential of fermented milk products could be improved by increased production of bioactive peptides through controlled fermentation using appropriate proteolytic starter strain.     

Enhancement of stilbene compounds and anti-inflammatory activity of methyl jasmonate and cyclodextrin elicited peanut hairy root culture

A highly stable and productive hairy root culture from peanut cultivar Tainan9 (T9-K599) was established using Agrobacterium rhizogenes strain K599 (NCPPB 2659)-mediated transformation. Valuable phenolic compounds with antioxidant activity and stilbene compounds were produced and secreted into the culture medium after elicitation with 100 µM methyl jasmonate (MeJA) and 6.87 mM cyclodextrin (CD). The antioxidant activity of the culture medium was increased to the highest Trolox equivalent antioxidant capacity (TEAC) value (28.30?±?2.70 mM Trolox/g DW) in the group treated with CD. The group co-treated with MeJA and CD exhibited the highest phenolic content, with a gallic acid equivalent (GAE) value of 10.80?±?1.00 µg gallic acid/g DW. The CuZn-SOD (CuZn superoxide dismutase) and APX (ascorbate peroxidase) antioxidant enzyme gene were up-regulated in the treatment with CD alone while the CuZn-SOD, GPX (glutathione peroxidase) and APX gene expression were down-regulated in the co-treatment with MeJA plus CD. The stilbene compounds resveratrol, trans-arachidin-1 and trans-arachidin-3 were detected by analysing the culture medium treated with CD alone and after co-treatment with MeJA and CD via HPLC. The LC-MS/MS results confirmed the presence of resveratrol, trans-arachidin-1, trans-arachidin-3, 4-Isopentadienyl-3,5,3′,4′-tetrahydroxystilbene (IPP), trans-3′-Isopentadienyl-3,5,4′-trihydroxystilbene (IPD) and arahypin-7. The results indicate that elicited peanut hairy roots can produce beneficial stilbene compounds that have antioxidant properties and anti-inflammatory activity. This peanut hairy root system could be applied as an experimental model to enhance the production of stilbene and other polyphenolic bioactive compounds.     

Effect of Cycloheximide on Development of Mitochondria in Germinating Pea Cotyledons

Polyethylene glycol (PEG) mediated transfection of Lactobacillus casei ATCC 27092 protoplasts by phage PL-1 DNA was done. The protoplasts were obtained by treatment with purified PL-1 phage N-acetylmuramidase in the presence of citrate. Optimum conditions for transfection were 50% PEG 4,000, 15 µg protamine sulfate/ml, 0.15 m sucrose, and 10 m m MgSO₄ in MR medium (pH 6.0). The extent of transfection was proportional to the amounts of DNA added, and the greatest efficiency of transfection after a 10-min incubation was about 3.3 × 10⁵ PFU/µg DNA. The eclipse period of growth of progeny phages in the transfectants was 3 hr and the average burst size was 200.     

Design,synthesis and cholinesterase inhibitory properties of new oxazole benzylamine derivatives

Abstract

The enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are primary targets in attenuating the symptoms of neurodegenerative diseases. Their inhibition results in elevated concentrations of the neurotransmitter acetylcholine which supports communication among nerve cells. It was previously shown for trans-4/5-arylethenyloxazole compounds to have moderate AChE and BChE inhibitory properties. A preliminary docking study showed that elongating oxazole molecules and adding a new NH group could make them more prone to bind to the active site of both enzymes. Therefore, new trans-amino-4-/5-arylethenyl-oxazoles were designed and synthesised by the Buchwald-Hartwig amination of a previously synthesised trans-chloro-arylethenyloxazole derivative. Additionally, naphthoxazole benzylamine photoproducts were obtained by efficient photochemical electrocyclization reaction. Novel compounds were tested as inhibitors of both AChE and BChE. All of the compounds exhibited binding preference for BChE over AChE, especially for trans-amino-4-/5-arylethenyl-oxazole derivatives which inhibited BChE potently (IC₅₀ in µM range) and AChE poorly (IC₅₀?100?µM). Therefore, due to the selectivity of all of the tested compounds for binding to BChE, these compounds could be applied for further development of cholinesterase selective inhibitors.

• HIGHLIGHTS

• Series of oxazole benzylamines were designed and synthesised

• The tested compounds showed binding selectivity for BChE

• Naphthoxazoles were more potent AChE inhibitors

     

Co-fermentation of cassava waste pulp hydrolysate with molasses to ethanol for economic optimization

Cassava waste pulp (CWP)–enzymatic hydrolysate was co-fermented with molasses (CWP-EH/molasses mixture) with the aim to optimize ethanol production by Saccharomyces cerevisiae TISTR 5606 (SC 90). The optimal fermentation conditions for ethanol production using this mixture were 245 g/L initial total sugar supplemented with KH₂PO₄ (8 g/L), at 30 °C for 48 h of fermentation under an oxygen-limited condition with agitation at 100 rpm, producing an ethanol concentration of 70.60 g/L (0.31 g ethanol/g total sugar). The addition of cassava tuber fiber (solid residue of CWP after enzymatic hydrolysis) at 30 g/L dry weight to the CWP-EH/molasses mixture increased ethanol production to 74.36 g/L (0.32 g ethanol/g total sugar). Co-fermentation of CWP-EH with molasses had the advantage of not requiring any supplementation of the fermentation mixture with reduced nitrogen.     

The impact of heterologous catalase expression and superoxide dismutase overexpression on enhancing the oxidative resistance in <Emphasis Type="Italic">Lactobacillus casei</Emphasis>

Two heme-dependent catalase genes were amplified from genomic DNA of Lactobacillus plantarum WCFS1 (KatE1) and Lactobacillus brevis ATCC 367 (KatE2), respectively, and a manganese-containing superoxide dismutase from Lactobacillus casei MCJΔ1 (MnSOD) were cloned into plasmid pELX1, yielding pELX1-KatE1, pELX1-KatE2 and pELX1-MnSOD, then the recombinant plasmids were transferred into L. casei MCJΔ1. The strains of L. casei MCJΔ1/pELX1-KatE1 and L. casei MCJΔ1/pELX1-KatE2 were tolerant at 2 mM H₂O₂. The survival rates of L. casei MCJΔ1/pELX1-KatE1 and L. casei MCJΔ1/pELX1-KatE2 were 270-fold and 300-fold higher than that of the control strain on a short-term H₂O₂ exposure, and in aerated condition, the survival cells counts were 146- and 190-fold higher than that of the control strain after 96 h of incubation. Furthermore, L. casei MCJΔ1/pELX1-MnSOD was the best in three recombinants which was superior in the living cell viability during storage when co-storage with Lactobacillus delbrueckii subsp. lactis LBCH-1.     

Enhancement of γ-aminobutyric acid production in recombinant Corynebacterium glutamicum by co-expressing two glutamate decarboxylase genes from Lactobacillus brevis

γ-Aminobutyric acid (GABA), a non-protein amino acid, is a bioactive component in the food, feed and pharmaceutical fields. To establish an effective single-step production system for GABA, a recombinant Corynebacterium glutamicum strain co-expressing two glutamate decarboxylase (GAD) genes (gadB1 and gadB2) derived from Lactobacillus brevis Lb85 was constructed. Compared with the GABA production of the gadB1 or gadB2 single-expressing strains, GABA production by the gadB1–gadB2 co-expressing strain increased more than twofold. By optimising urea supplementation, the total production of l-glutamate and GABA increased from 22.57 ± 1.24 to 30.18 ± 1.33 g L^?1, and GABA production increased from 4.02 ± 0.95 to 18.66 ± 2.11 g L^?1 after 84-h cultivation. Under optimal urea supplementation, l-glutamate continued to be consumed, GABA continued to accumulate after 36 h of fermentation, and the pH level fluctuated. GABA production increased to a maximum level of 27.13 ± 0.54 g L^?1 after 120-h flask cultivation and 26.32 g L^?1 after 60-h fed-batch fermentation. The conversion ratio of l-glutamate to GABA reached 0.60–0.74 mol mol^?1. By co-expressing gadB1 and gadB2 and optimising the urea addition method, C. glutamicum was genetically improved for de novo biosynthesis of GABA from its own accumulated l-glutamate.     

Probiotic Properties and Cellular Antioxidant Activity of <Emphasis Type="Italic">Lactobacillus plantarum</Emphasis> MA2 Isolated from Tibetan Kefir Grains

Lactobacillus plantarum MA2 was isolated from traditional Chinese Tibetan kefir grains. Its antioxidant properties had been demonstrated in vitro and in vivo previously. In the present study, the probiotic characteristics of this strain were further evaluated by investigating its acid and bile salt tolerances, cell surface hydrophobicity, and autoaggregation, respectively. In addition, the cellular antioxidant activity (CAA) assay was applied to test the antioxidant capacity of the isolate in different growth phases. Same method was also used to evaluate the antioxidant capacity of its fermentation supernatant, cell-free extract, and intact cell quantitatively. The results of probiotic characteristic tests showed that MA2 could survive at pH 2.5 and 0.3% bile salt. Meanwhile, the measurements of cell surface hydrophobicity and autoaggregation were 45.29?±?2.15 and 6.30?±?0.34%, respectively. The results of cellular antioxidant activity tests indicated that MA2 had high antioxidant potential. The CAA value of logarithmic phase cell-free extract of MA2 (39,450.00?±?424.05 μmol quercetin equivalents/100 g sample) was significantly higher than that in stationary phase cell-free extract (3395.98?±?126.06 μmol quercetin equivalents/100 g sample) and that of fermentation supernatant in logarithmic phase (2174.41?±?224.47 μmol quercetin equivalents/100 g sample) (p?<?0.05). The CAA method was successively applied to evaluate the antioxidant capacity of MA2 in this study, which suggests that it could be used as a useful method for lactic acid bacteria antioxidant potential evaluation.     

<Emphasis Type="Italic">Lactobacillus futsaii</Emphasis> CS3, a New GABA-Producing Strain Isolated from Thai Fermented Shrimp (<Emphasis Type="Italic">Kung</Emphasis>-<Emphasis Type="Italic">Som</Emphasis>)

Kung-Som is a popular traditional Thai fermented shrimp product. It is rich in glutamic acid, which is the major substrate for the biosynthesis of gamma-aminobutyric acid (GABA) by lactic acid bacteria (LAB). In the present study, LAB from Kung-Som were isolated, screened for GABA formation, and the two isolates that transform glutamic acid most efficiently into GABA were identified. Based on the API-CHL50 fermentation profile and a phylogenetic tree of 16S rDNA sequences, strain CS3 and CS5 were identified as Lactobacillus futsaii, which was for the first time shown to be a promising GABA producer. L. futsaii CS3 was the most efficient microorganism for the conversion of 25 mg/mL monosodium glutamate (MSG) to GABA, with a maximum yield of more than 99% conversion rate within 72 h. The open reading frame (ORF) of the glutamate decarboxylase (gad) gene was identified by PCR. It consists of 1410 bp encoding a polypeptide of 469 amino acids with a predicted molecular weight of 53.64 kDa and an isoelectric point (pI) of 5.56. Moreover, a good quality of the constructed model of L. futsaii CS3 was also estimated. Our results indicate that L. futsaii CS3 could be of interest for the production of GABA-enriched foods by fermentation and for other value-added products.     

Staining of Negri Bodies

The following procedure for staining Negri bodies in sections is based on methods previously described by MacNeal, by Haynes, and by Richter:

Fixation:

1. 1. Zenker's solution 4 hours at 37°C or Dominici's 3 hours.

2. 2. 70% alcohol, 12 to 18 hours at room temperature.

3. 3. 80% alcohol, about 5 to 6 hours.

4. 4. 90% alcohol, about 4 to 6 hours.

5. 5. Absolute alcohol about 16 hours.

6. 6. Ether and absolute alcohol aa, about 8 hours.

7. 7. 16 to 24 hours in the following mixture: celloidin 1 g., methyl salycilate 25 cc., abs. alcohol 25 cc., ether 25 cc.

8. 8. Chloroform and paraffin, 2 to 3 hours.

9. 10. Paraffin, 1 to 1 1/2 hours.

10. 11. Embed.

staining:

1. 1. Cut sections 4 to 5 μ.

2. 2. Bring section to water and cover with Lugol's iodine for 10 minutes.

3. 3. Decolorize with a 2% sodium thiosulfate (hypo).

4. 4. Wash thoroly with water.

5. 5. Cover with a mixture of equal parts of 0.5% phloxine and 1% eosin Y (National Aniline brand) and leave for 15 minutes.

6. 6. Wash with water and stain 2 to 5 minutes in 0.1% azure B (National Aniline).

7. 7. Wash with 96% alcohol and decolorize in a mixture of 2 parts absolute alcohol with 1 part clove oil, ordinarily for not more than 1/2 to 1 minute.

8. 8. Dehydrate rapidly, clear, and mount in Yucatan Elemi.

     

Das Vorkommen von Malatenzym und Malo-Lactat-Enzym bei verschiedenen Milchsäurebakterien

1. Malic enzyme was induced by malic acid and malo-lactic enzyme was induced by malic acid and glucose in cells of three strains ofLactobacillus casei that were able to grow on malate as carbon source. Two strains ofStreptococcus faecalis formed malic enzyme only, whereas only malo-lactic enzyme was formed by a glucose requiring strain ofStreptococcus lactis.
2. Given sequential induction, cells ofLactobacillus casei M40 were found to contain malic enzyme and malo-lactic enzyme simultaneously.
3. Malic enzyme and malo-lactic enzyme have been separated by chromatography on Sephadex G-200. These two enzymes have a different pH optimum, different affinities for substrates, form different end products from malate, and have molecular weights of 120000 and 150000 daltons respectively.

     

Biofilm formation and antimicrobial sensitivity of lactobacilli contaminants from sugarcane-based fuel ethanol fermentation

Industrial ethanol fermentation is subject to bacterial contamination that causes significant economic losses in ethanol fuel plants. Chronic contamination has been associated with biofilms that are normally more resistant to antimicrobials and cleaning efforts than planktonic cells. In this study, contaminant species of Lactobacillus isolated from biofilms (source of sessile cells) and wine (source of planktonic cells) from industrial and pilot-scale fermentations were compared regarding their ability to form biofilms and their sensitivity to different antimicrobials. Fifty lactobacilli were isolated and the most abundant species were Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum. The majority of the isolates (87.8%) were able to produce biofilms in pure culture. The capability to form biofilms and sensitivity to virginiamycin, monensin and beta-acids from hops, showed inter- and intra-specific variability. In the pilot-scale fermentation, Lactobacillus brevis, L. casei and the majority of L. plantarum isolates were less sensitive to beta-acids than their counterparts from wine; L. brevis isolates from biofilms were also less sensitive to monensin when compared to the wine isolates. Biofilm formation and sensitivity to beta-acids showed a positive and negative correlation for L. casei and L. plantarum, respectively.