Leuconostoc Sp Research Articles

Microbiota-derived acetylcholine can promote gut motility in Drosophila melanogaster.

The gut microbiota is crucial for intestinal health, including gastrointestinal (GI) motility. How commensal bacterial species influence GI motility has not been fully elucidated. A major factor of GI motility is the gut contraction promoting the propulsive movement of orally ingested materials. Here, we developed a method to monitor and quantify gut contractions in living Drosophila melanogaster larvae. We found that the culture medium of an isolated strain Lactiplantibacillus plantarum Lsi promoted gut contraction in vivo, which was not observed in Leuconostoc sp. Leui nor Acetobacter persici Ai culture medium. To identify bacteria-derived metabolites, we performed metabolome analysis of the culture media by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Of the 66 metabolites detected, we found that some metabolites changed in a species-specific manner. Among them, acetylcholine was specifically produced by L. plantarum. Feeding exogenous acetylcholine increased the frequency of gut contractions, which was blocked by D-tubocurarine, an inhibitor of nicotinic acetylcholine receptors. In this study, we propose a mechanism by which the gut microbiota influences Drosophila gut motility. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.

Detoxification of Bacterial Toxins in Soured Soups Using the Extract of Aidan Tree (Tetrapleura Tetraptera L.) Fruit

The study evaluated the use of Tetrapleura tetraptera fruit extract to detoxify bacterial toxins in soured soups. Tetrapleura tetraptera fruit extracts were prepared and analyzed for phytochemicals. Three different types of soured soups (egusi, ogbono, and Abua native soup) were used. The soups were prepared and left for 24 hours at room temperature to sour. The pour-plate method and streaking techniques were used to isolate and identify the bacteria. The lateral flow assay device, Biothreat Alert test strip, and enzyme immunoassay kits were used to detect the bacterial toxins, while the extracts were used to test the detoxifying effectiveness of the bacterial toxins. The results showed that Lactobacillus sp, Bifidobacterium sp, Streptococcus sp, Pediococcus sp, Leuconostoc sp Bacillus cereus, Clostridium perfringens, Campylobacter jejuni, Vibrio parahaemolyticus, Yersinia enterocolitica, Salmonella sp, Shigella sp, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes were associated with the soured soups; alkaloids, cardiac glycosides, flavonoids, phenols, saponins, steroids, tannins, and terpenoids were present. The quantity of saponin (5.670±0.15), steroid (4.102±0.13), terpenoid (3.194±0.03), and alkaloid (0.596± 0.01) were very high in concentrations; phenol (0.373±0.02) and tannin (0.366±0.02) were present in moderately high concentrations, while cardiac glycoside (0.007± 0.00) and flavonoid (0.073±0.00) were present in low concentrations. The toxins detected in the soured soups included Bacillus cereus and Staphylococcus aureus exotoxins. Therefore, it is concluded that the extract of Tetrapleura tetraptera has no detoxifying effect on the stability of the bacterial toxins and should, therefore, be discouraged.

Influence of selected lactic acid bacteria on the sensory characteristics of soft cheese with natural rind

Cheese is obtained by the coagulation of milk, followed by maturation under the action of microorganisms which are responsible for the development of physicochemical and organoleptic characteristics of cheese. Among various microorganisms, lactic acid bacteria (LAB) play an essential role in establishing sensory characteristics of the cheese. In Cameroon, the effect of isolated LAB on the sensory characteristics of cheese produced from local cow milk has not yet been investigated. Therefore, the present work aimed to isolate LAB and evaluate their influence on the physicochemical and sensory characteristics of locally produced soft cheeses. Four strains of LAB were isolated and identified as Enterococcus sp.1, Enterococcus sp.2, Pediococcus sp., and Leuconostoc sp. These isolates were combined in batches for production of cheeses, including Frm 741 (Enterococcus sp.1 and Enterococcus sp.2), Frm 891 (Enterococcus sp.2 and Leuconostoc sp.), Frm 683 (Pediococcus sp. and Enterococcus sp.1), Frm 425 (Pediococcus sp. and Leuconostoc sp.), Frm 503 (Pediococcus sp. and Enterococcus sp.2), Frm 439 (Leuconostoc sp. and Enterococcus sp.1), and Frm 625 (Enterococcus sp.1, Enterococcus sp.2, Leuconostoc sp., and Pediococcus sp.). Cheese produced from the combination of Enterococcus sp.1 and Enterococcus sp.2 (Frm 741), unlike the others, did not drain properly throughout the production process. However, all products showed excellent microbiological quality in relation to biological contaminants, such as Salmonella, staphylococci, and coliforms. Moreover, cheese Frm 425 was most appreciated by consumers for its sweet taste, yellow colour, pleasant smell, and low acidity (51.7°D). On the other hand, cheese Frm 439 was least appreciated by consumers owing to its bad odour, bitter taste, and high acidity (144.9°D). Taken together, the present work demonstrated that the isolated LAB could be used to produce soft cheese with a natural rind and unique sensory characteristics that are appreciated by Cameroonian consumers.

EDUCATION AND TRAINING REGARDING BENEFICIAL PROPERTIES OF KIMCHI’S PROBIOTICS AS AN EFFORT TO INCREASE HEALTH WORKERS’ KNOWLEDGE

Introduction: Kimchi is a traditional Korean dish made by fermenting various kinds of vegetables with lactic acid bacteria, such as Lactobacillus sp. And Leuconostoc sp. These micro bacteria can serve as a probiotic that can exert the human immune system. This knowledge is essential for a global society, including health professionals. The aim of this education and training activity is to increase health workers’ knowledge about kimchi, probiotics, and their role so that they can conduct further research and educate their patients and also the larger community. Methods: This education and training is carried out using lecture-based talks, with interactive communication. The audience is 25 nurses as health workers at Sultan Agung Islamic Hospital. Pre-post test questionnaire was used to evaluate participants’ knowledge about probiotics and Kimchi. Results: Before the education and training activity was carried out, a pre-test of Kimchi Knowledge revealed that 84% of the participants had good knowledge. After the education and training activity was done, the results showed an increase in knowledge where 96% of the participants had good knowledge (p=0,018). The results of the pre-test of Probiotic Knowledge revealed that 68% of the participants had good knowledge. After the education and training activity was done, the results showed an increase in knowledge where 84% of the participants had good knowledge (p=0,001). Conclusion: Education and Training regarding the beneficial properties of Kimchi, probiotics, and their role can increase health workers’ knowledge so that they can use it as a starting point to develop new studies and educate the larger community.

Assessment of Effect of Different Packaging Materials on Microbial Quality of Locust Beans during Storage

This study assesses the effect of different packaging materials on the microbial quality of Africa Locust beans during storage. Locust beans (Dawadawa) also known as iru, among the Yorubas in South-west Nigeria, is a popular condiment used as a taste and flavour enhancer in soup and dishes in Africa. Locust bean is traditionally produced from locust beans seed (Parkia biglobosa) and preserved using different packaging materials before use in order to prolong its shelf life. The Microbiological examination of the produced locust beans was carried out on samples wrapped with different packaging materials such as plastic containers, nylon, and dry banana leaves. The suspected organisms isolated include Salmonella spp, Staphylococcus aureus, Streptococcus lactis, Pseudomonas aeruginosa, Lactobacillus plantarium, Bacillus cereus, Bacillus subtilis, Leuconostoc sp, Escherichia coli and Micrococcus sp. It was observed from this study that locust beans packaged with banana leaves had the highest microbial load, few of which are of public health concern while plastic containers had the least microbial load. It is therefore recommended that locust beans should be produced and packaged with sealed plastic containers to avoid contamination by pathogenic organisms.

Antibiofilm and Antivirulence Activities of Gold and Zinc Oxide Nanoparticles Synthesized from Kimchi-Isolated Leuconostoc sp. Strain C2.

The rapid emergence of antimicrobial resistance (AMR) among bacterial pathogens results in antimicrobial treatment failure and the high mortality rate associated with AMR. The application of nanoparticles synthesized from probiotics will be widely accepted due to their efficacy and biocompatibility in treating microbial infections in humans. The current work sought to isolate and identify lactic acid bacteria (LAB) from Kimchi. Based on 16S rRNA gene sequencing, the LAB isolate C2 was identified as a member of the genus Leuconostoc. The obtained supernatant from Leuconostoc sp. strain C2 was employed for the green synthesis of metal (AuNPs) and metal oxide (ZnONPs) nanoparticles. UV-vis absorption spectra, FTIR analysis, XRD, DLS, FE-TEM, and EDS mapping were used to fully characterize these C2-AuNPs and C2-ZnONPs. The C2-AuNPs were found to be spherical in shape, with a size of 47.77 ± 5.7 nm and zeta potential of -19.35 ± 0.67 mV. The C2-ZnONPs were observed to be rod-shaped and 173.77 ± 14.53 nm in size. The C2-ZnONPs zeta potential was determined to be 26.62 ± 0.35 mV. The C2-AuNPs and C2-ZnONPs were shown to have antimicrobial activity against different pathogens. Furthermore, these nanoparticles inhibited the growth of Candida albicans. The antibiofilm and antivirulence properties of these NPs against Pseudomonas aeruginosa and Staphylococcus aureus were thoroughly investigated. C2-AuNPs were reported to be antibiofilm and antivirulence against P. aeruginosa, whereas C2-ZnONPs were antibiofilm and antivirulence against both P. aeruginosa and S. aureus. Furthermore, these nanoparticles disrupted the preformed mature biofilm of P. aeruginosa and S. aureus. The inhibitory impact was discovered to be concentration-dependent. The current research demonstrated that C2-AuNPs and C2-ZnONPs exhibited potential inhibitory effects on the biofilm and virulence features of bacterial pathogens. Further studies are needed to unravel the molecular mechanism behind biofilm inhibition and virulence attenuation.

Occurrence of Lactobacilli in the Traditional Preparation of Curd

Curd is a dairy product produced via way of means of coagulating milk in a process known as curdling. The objective of this current study was to prepare curd traditionally in the laboratory and identify Lactobacilli species with potential probiotic activities. Cow and goat milk was collected, and curd was prepared by adding lime and starter culture in different amounts. Among prepared curd samples, best quality curd was selected, and from the selected curd samples, lactic acid bacteria were isolated and subsequent subculturing was carried out, and ten different Lactobacilli isolates were obtained and identified based on morphological, physiological and biochemical characteristics.Isolates were subjected to test the antagonistic effect among the Lactobacilli isolates and against selected bacterial strains by standard agar well diffusion method. Antibiotic sensitivity test by disc method was carried out by using antibiotics and the production of lactic acid by titration method.Ten different Lactobacilli isolates were classified into three different genera Lactobacillus sp., Pediococcus sp. and Leuconostoc sp. Growth of all Lactobacilli was observed under acidic and neutral pH. Lactic acid bacteria exhibited different tolerant levels to bile salt. No antagonistic effect was observed among the Lactobacilli isolates. But 80% of lactobacilli isolates had antibacterial activity on selected bacterial species. The growth of Bacillus sp. was predominantly inhibited by Lactic acid bacterial isolates (90%), Pseudomonas aeruginosa (30%), Proteus sp. and Staphylococcus aureus (50%) and E.coli (30%). Lactobacillus sp. (CL2) predominantly inhibited all tested bacteria (100%). Growth of the Lactobacilli isolates was inhibited by tested antibiotics except for Lactobacillus sp. (CC3) was resistant to bacitracin only. All of the Lactic acid bacterial isolates produced a considerable amount of lactic acid. Under the controlled conditions, the Lactobacillus sp. (GL1) produced a significantly high level of lactic acid (0. 315%), whereas Lactobacillus sp. (CL3) produced less amount of lactic acid (0.099%). Keywords: Curd, Lactic acid bacteria, Antagonistic effect, Antibacterial sensitivity, Lactic acid

​Potential of Lactic Acid Bacteria in Plant Growth Promotion

Background: Lactic acid bacteria are regarded the most important bacteria concerning food fermentation, pharmaceutical and special dietary applications. Strains have been isolated from environments rich in available carbohydrate substrates, such as food and feed, but also in human and animal cavities and in sewage and plant material. Besides lactic acid, other side products include acetate, ethanol, CO2, formate and succinate. The most important advantage of Lactic acid bacteria making them suitable for the use in food biotechnology, is that they are generally recognized as safe (GRAS). Studies on Lactic acid bacteria isolated from aerial parts of plants are scarce. Bacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria. Several substances produced by antagonistic rhizobacteria have been related to pathogen control and indirect promotion of growth in many plants. The present work explores the potential use of Lactic acid bacteria in promotion of plant growth. Methods: Three isolates were obtained from aerial parts of pomegranate plant and confirmed by 16S rRNA sequencing to belong to Leuconostoc sp. The isolates were checked for plant growth promoting traits viz. antifungal activity, production of plant growth hormones, enzymes and 1-amino cyclopropane carboxylate deaminase activity. Result: As LAB showed plant growth promoting traits, they can be suitably used for plant growth promotion.

Comparative lactic acid bacteria (LAB) profiles during dadih fermentation with spontaneous and back-slopping methods, as identified by terminal-restriction fragment length polymorphism (T-RFLP)

The diversity of lactic acid bacteria (LAB) present during the manufacture of traditional fermented buffalo milk from West Sumatra, known as dadih, was studied via a culture-independent approach using terminal-restriction fragment length polymorphism (T-RFLP) to compare the dynamic diversity in back-slopping and spontaneous fermentation methods. Total LAB and pH were measured in freshly prepared buffalo milk and in \textit{dadih} fermented for 24 and 48 hours. The results indicated significant differences between the fermentation methods, with higher total LAB, and greater phylotype richness and relative abundance being identified in the back-slopping method. Terminal fragment lengths (TRFs) of 68 and 310 bp were common to both techniques, similar to those of Lactobacillus fermentum, Fructobacillus pseudoficulneus, Leuconostoc citreum, Leuconostoc kimchii, and Leuconostoc sp. The changes in phylotype number (species number) and relative abundances of LAB communities identified are expected to produce data needed to formulate the best fermentation process for dadih manufacturing. A 24-hour back-slopping fermentation method is recommended, as fermentation time of longer than 24 hours reduced viable LAB significantly. Our results also indicated that the T-RFLP technique is not only clearly sensitive enough and adequate for segregating LAB diversity in both fermentation methods, but that it also provides good information regarding the structure of microbial communities and their composition change during the fermentation process.

Potential antimicrobial and antiadhesive activity of crude bio-surfactants produced by Leuconostoc sp strains coated on rubber-silicone tubes

The present study focused on screening of biosurfactants produced by Leu-conostoc strains isolated from dromedary milk with antimicrobial and antiad-hesive properties against various pathogenic microorganisms and its poten-tial application in medical fields as an antibiofilm agent. After identification of the selected strains by mass spectrometry, screening methods for biosur-factants production were used, including drop collapse, oil displacement, surface tension and emulsification index. Antiadhesive assays were carried out against six pathogenic microorganisms in polystyrene surface, and ap-plied on rubber silicone tubes. Four lactic acid bacteria were isolated and identified as Leuconostoc sp according to MALDITOF MS spectrometry. Bio-surfactants isolated from Leuconostoc strains reduced tension surface from 72.0 to 45.7 by strain BY14, with an emulsification efficiency (E24) after 24h of 63%. The crude biosurfactants were effective against most pathogenic microorganisms with inhibition percentage from 92.3% to 44.3% after adhe-sion to polystyrene. Otherwise, the antiadhesive activity displayed values from 75.67% to 13.2%. The result of application test demonstrated that the selected crude biosurfactants reduced significantly all the deposited microbi-al biofilm from rubber silicone tubes. This study suggest that biosurfactants could have a promising role as an effective antibiofilm to prevent microbial colonization on medical devices.

Bacteriological quality of commercially prepared fermented Ogi (Akamu) sold in Some Parts of Afikpo Area in Ebonyi State

In this study ogi (akamu) prepared from fermented maize sold in Enohia, Afikpo and Unwana were subjected to bacteriological test together with the laboratory prepared ogi for bacterial quality using the standard microbiological method. The commercial purchased ogi from the markets of (Enohia, Unwana and Afikpo) showed total bacterial growth of 5.6 × 107, 2.0 × 103, 4.2 × 102 and 3.6 × 106 respectively. Staphylococci growth count of 4.2×102, 2.9×102 and 3.5 × 102 were recorded respectively, while Coliform count recorded 2.0×103, 1.2×103 and 1.5×103 and Lactic acid bacterial loads of 3.6×106, 2.7×106 and 3.2 × 106 respectively. The bacteria isolated from the commercial and laboratory fermented pap were Lactobacillus sp, Staphylococcus sp, Leuconostoc sp, Micrococcus sp, Salmonella sp, E. coli, Citrobacter sp and Klebsiella sp. Lactobacillus sp Leuconostoc sp and Citrobacter sp were present in all the samples, Micrococcus sp and Klebsiella sp were isolated from Enohia and Unwana markets ogi respectively, while E. coli and Staphylococcus sp were present in Enohia, Unwana and Afikpo markets. Salmonella sp were isolated from the three markets. No pathogenic bacteria was isolated from the laboratory Prepared ogi (Akamu). Hence, there are chances of contracting food borne diseases from commercially prepared ogi in the local areas of study. Therefore, there is need for sanitary measures in the production of fermented cereals such as ogi so as to minimize the rate of food borne pathogens during processing and storage of such cereals.

Effect of Starter Culture on the Fatty Acid and Amino Acid Profile of Fermented <i>Parkia biglobosa</i> Seeds

Iru , a condiment used for seasoning soup is often obtained from the fermentation of Parkiabiglobosa seeds. The present study therefore investigates the effect of different starter culture on the amino and fatty acid profile of Parkiabiglobosa seed fermented to produce iru. Starter culture of Lactobacillus plantarum, Bacillus subtilis and Leuconostoc sp were used to ferment Parkiabiglobosa seeds. The bacterial load increased from 0.00 log10cfu/g in boiled raw sample to 8.67 log10cfu/g in naturally fermented sample. Fermentation significantly (P<0.05) increased the quantity of the amino acids in fermented samples. Aspartic acid (25.85 g/100g) and linoleic acid (42.99 %) were the highest amino and fatty acids respectively in the fermented samples. The result from this study reveals that fermentation significantly increase the amino and fatty acid profile of Parkiabiglobosa fermented to produce iru, a Nigerian condiment.

Comparative genome analysis provides shreds of molecular evidence for reclassification of Leuconostoc mesenteroides MTCC 10508 as a strain of Leu. suionicum

This study presents the whole-genome comparative analysis of a Leuconostoc sp. strain, previously documented as Leu. mesenteroides MTCC 10508. The ANI, dDDH, dot plot, and MAUVE analyses suggested its reclassification as a strain of Leu. suionicum. Functional annotation identified a total of 1971 genes, out of which, 265 genes were mapped to CAZymes, evincing its carbohydrate transforming capability. The genome comparison with 59 Leu. mesenteroides and Leu. suionicum strains generated the core and pan-genome profiles, divulging the unique genes in Leuconostoc sp. MTCC 10508. For the first time, this study reports the genes encoding alpha-xylosidase and copper oxidase in a strain of Leu. suionicum. The genetic information for any possible allergenic molecule could not be detected in the genome, advocating the safety of the strain. The present investigation provides the genomic evidence for reclassification of the Leuconostoc sp. strain and also promulgates the molecular insights into its metabolic potential.

Wild bacterial probiotics fed to larvae of mass-reared Queensland fruit fly [Bactrocera tryoni (Froggatt)] do not impact long-term survival, mate selection, or locomotor activity.

Queensland fruit fly [Bactrocera tryoni (Froggatt), Diptera, Tephritidae] is the most devastating insect pest impacting Australian horticulture. The Sterile Insect Technique (SIT) is an important component of tephritid pest management programs. However, mass-rearing and irradiation (to render insects sterile) may reduce the fitness and performance of the insect, including the ability of sterile males to successfully compete for wild females. Manipulation of the gut microbiome, including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass-reared sterile flies, however there are fewer published studies targeting the larval stage. In this study, we supplemented the larval stage of mass-reared B. tryoni with bacterial probiotics. We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B. tryoni larvae including Asaia sp., Enterobacter sp., Lactobacillus sp., Leuconostoc sp. We also tested a consortium of all four of these bacterial isolates. The fitness parameters tested included adult survival in field cages, laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females, and laboratory locomotor activity of adult flies. None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival, mate selection or locomotor activity of adult B. tryoni, which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids. Future work is needed to determine if feeding the same, and/or other probiotics to adults, as opposed to larvae can positively impact survival, mating performance, mating competitiveness and locomotor activity of B. tryoni. The bacterial group(s) and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass-rearing programs.

The potency of cassava starch (var. kristal merah and var. revita) for bio-succinic acid production using indigenous lactic acid bacteria (Leuconostoc sp)

Cassava of local strain, a plentiful agricultural product in Indonesia was evaluated for biosuccinic acid production via saccharification and fermentation using indigenous lactic acid bacteria (Leuconostoc sp). Cassava starch is an ideal biosuccinic acid feedstock due to its low price and high sugar content. Conversion of cassava starch into succinic acid is an effort to obtain added-value of the local product. Succinic acid has been well-known as an important platform chemical and being top 12 building block in the chemical industries. In the current study, saccharification of starch was carried out using available glucoamylase enzymes produced by Aspergillus awamori KT 11 (Glutech) in the temperature 60°C and 200 rpm. Results revealed the best yield of total reducing sugar accumulation (62.3 g L−1) was obtained when the ratio of starch solution of var. kristal merah (25% w/v) and glucoamylase was kept to 3:1. HPLC analysis of sugar also showed three different sugar were produced during saccharification: glucose, maltose, and maltotriose. Fermentation of the liquid sugar as a carbon source in various media showed that Leuconostoc sp could produce highest succinic acid in medium SPM, with concentration 3.4 g L−1 in 72 h for var. kristal merah and 3.6 g L−1 g in 48 h for var. revita. The other valuable organic acids, such as lactic acid, citric acid, formic acid, and acetic acid were also formed during fermentation process, with concentration less than 3 g L−1. The results suggested that cassava starch of 2 local strains (var. kristal merah and var. revita) has the potential to be an alternative substrate for efficient and economic valuable organic acids production such as succinic acid.

Screening of Lactic Acid Bacteria from Effluent Samples of Jaipur Dairy

Probiotics are good or friendly bacteria that are essential for good health. Probiotic literally means “for life” as opposed to antibiotic meaning “against life.” Probiotics are single-celled lactic bacteria organisms occurring primarily singly or in pairs. Probiotics are live microbial food supplements or components of bacteria, which have been shown to have beneficial effects on human health. The most commonly used probiotic strains belong to genera Lactobacillus sp., Bifidobacterium and Saccharomyces sp. taking into consideration, the above cited facts, and the present study was conducted to isolate and characterise probiotic strains from dairy waste water. Untreated and treated dairy waste water samples were collected from Jaipur dairy in accordance with standard procedures. Morphological and biochemical tests were conducted to identify the strains. The most common and predominant isolate was found to be associated with genera Leuconostoc sp.

Effect of fermentation and malting on some cereal weaning foods enriched with African locust beans

Effect of fermentation and malting on some cereal weaning foods enriched with African locust beans were carried out. Cereals (wheat and millet) were malted for the period of 144 hours and further fermented for 48 hours by natural fermentation. The millet, wheat and locust bean flours were mixed together in the ratio 70:70:40 (w/w) to produce fortified fermented-malted food .The same ratio were used in the formulation of unmalted /unfermented food and fortified products. Microbial analysis of the prepared foods were carried out using pour plate method. Physicochemical, proximate analysis were carried out using standard procedures. Nine (9) points hedonic scale were used for the sensory evaluation on the products .Bacteria such as Lactobacillus sp, Bacillus sp, Clostridium sp, Leuconostoc sp, Staphylococcus sp, Streptococcus sp, E.coli, Salmonella sp and fungal isolates include Aspergillu ssp, Saccharomyces sp, Candida sp, Penicillium sp, Mucor and Rhizopus sp were isolated from the fermented grains. Staphylococcus sp, E.coli, Salmonella sp and some Moulds were isolated after 24 hours of fermentation and malting of the grains. The pH of 3.89 in millet and 4.04 in wheat were observed during malting and fermentation processes. Total titratable acidity (TTA) of malted/fermented millet was 2.46% and wheat had 2.31% TTA. Percentage crude protein increased from 3.33% in malted/fermented blend (sample A) to 6.3% while unmalted/unfermented (sample B) and fortified product (sample C) had decrease in % crude protein. Percentage fat content decreased from 6.17% in sample A to 5.9%. The % crude carbohydrate content decrease from 80.43 in sample A to 80.15 but higher values were obtained in sample B with sample C having 80.35%.Percentage moisture and ash content decreased after malting and fermentation in sample A and B except in sample C. The mean scores of sensory evaluation revealed that the formulated malted/fermented and fortified foods were liked very much compared to the unmalted/unfermented foods which are moderately and slightly liked.Keywords: Fermentation, bacteria, malting, cereal weaning foods, moulds

Changes in soymilk during fermentation with kefir culture: oligosaccharides hydrolysis and isoflavone aglycone production

The objective of this study was to evaluate the changes in oligosaccharides and isoflavone aglycone content in soymilk during fermentation with commercial kefir culture. Soymilk was fermented with kefir culture at 25 °C for 30 h. The counts of lactic acid bacteria, Lactococcus lactis, Leuconostoc sp and yeasts; measurements of pH, acidity, α-galactosidase and β-glucosidase activity, sugar and isoflavone contents were performed at the intervals of time. In the fermented soymilk, the lactic acid bacteria counts increased from 7.6 log to 9.1 CFU g−1, pH reached to 4.9 and lactic acid reached 0.34 g 100 g− 1. The α-galactosidase was produced (0.016 AU g−1) with 100% raffinose and 92% stachyose hydrolysis being observed after the depletion of galactose, glucose and sucrose. Kefir culture produced β-glucosidase (0.0164 AU g−1), resulting in 100% bioconversion of glycitin and daidzin and 89% bioconversion of genistin into the corresponding aglycones. The fermented soymilk presented 1.67 μmol g−1 of daidzein, 0.28 μmol g−1 of glicitein and 1.67 μmol g −1 of genistein.

Optimization of a novel coconut milk supplemented dahi - a fermented milk product of Indian subcontinent

In this very first study, preparation of coconut milk supplemented dahi (curd) was reported. Coconut milk and cow milk in a ratio of 30:70 resulted in a good quality dahi. Two sets of cultures (Lactococcus lactis MTCC 3041 + Leuconostoc sp. MTCC 10508 and Lc. lactis MTCC 3041 + Lactobacillus plantarum MTCC 5422) were found to be suitable for fermentation of coconut milk and cow milk blend after 14 and 16 h of incubation at 30 and 37 °C, respectively, with a viable count of lactic acid bacteria was around 150 × 107 cfu/ml. The coconut milk blend dahi samples had a pH, titratable acidity and fat content of 4.5, 1.2 % lactic acid and 8.1 %, respectively. Addition of 10 % skim milk powder increased the water holding capacity of dahi. Addition of 6 % sucrose reduced the bitter like after-taste generated during the fermentation by Lb. plantarum. The coconut milk based dahi fermented using Lc. lactis and Lb. plantarum was found to be viscous than the dahi developed using Lc. lactis and Leuconostoc sp. 10508. The coconut milk based dahi was well accepted in sensory analysis. Coconut flavour profiling of coconut milk dahi detected by electronic nose matched well with the sensory analysis.

Comparison of biological activities in Sargassum siliquanstrum fermented by isolated lactic acid bacteria

Brown alga Sargassum siliquanstrum was fermented by isolated lactic acid bacteria including Weissella sp. SH-1, Lactobacillus sp. SH-1, Leuconostoc sp. SH-1, and Streptococcus sp. SH-1, which could efficiently utilize its biologically active materials. Total polyphenol contents, total flavonoid contents and angiotensin converting enzyme inhibitory activities were measured after confirmation of pH and 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activities. pH and DPPH radical scavenging activities plateaued after 2 days fermentation for each bacterium. Fermentation without algal debris showed better biological activities than fermentation with debris. Fermentation increased DPPH radical scavenging activities from 3.13% to 16.85% compared with non-fermented condition, with Lactobacillus sp. SH-1 being the most efficient. Weissella sp. SH-1 and Leuconostoc sp. SH-1 increased total polyphenol contents by 18.43% and total flavonoid contents by 5.70%, respectively, compared with non-fermented condition. Fermentation by Lactobacillus sp. SH-1 showed the highest angiotensin converting enzyme inhibitory activity (73.93%). Biological activities of S. siliquanstrum were upgraded by isolated lactic acid bacteria, which might be exploited in the development of functional materials or healthy drink products.