Evaluation of the mineral and antioxidant contents of fermented and extruded green plantain enriched with soyabean

Milk-derived proteins and minerals alter serum osteocalcin in prepubertal boys after 7 days

Lactic acid bacteria (LAB) play an important role as natural food preservatives. However, the characterization of the variety of their metabolites is limited. The objective of this study was to determine the production of specific metabolites of Lacticaseibacillus rhamnosus, Levilactobacillus brevis and Lactiplantibacillus plantarum by an optimized liquid chromatography with an ultraviolet/diode detection (HPLC-UV/DAD) method and to investigate their potential antimicrobial activity against specific food pathogens. Based on the results of this study, the main metabolites detected in Levilactobacillus brevis were 103.4 μg mL−1 DL-p-Hydroxyphenyllactic acid (OH-PLA) and 2.59 μg mL−1 vanillic acid, while 216.2 μg mL−1 OH-PLA, 19.0 μg mL−1 salicylic acid, 3.7 μg mL−1 vanillic acid, 6.9 μg mL−1 ferulic acid, 4.2 μg mL−1 benzoic acid and 1.4 μg mL−1 4-Hydrocinnamic acid were identified in the Lactiplantibacillus plantarum strain and 147.6 μg mL−1 OH-PLA and 4.9 μg mL−1 ferulic acid were identified in Lacticaseibacillus rhamnosus. This study provides alternative approaches for the molecules involved in the antimicrobial activity of food microorganism fermentation. These molecules may be used as antimicrobial ingredients in the food industry instead of conventional chemical preservatives.

This research produced wine from unripe plantain fruits using spontaneous fermentation method. The period of production was five days. The purpose of this study was to isolate and identify microorganisms associated with unripe plantain fruits, determine the physicochemical parameters of the fermenting medium. Microbial count, foaming density, alcohol content, enzymes assay, sensory analysis, physicochemical properties, mineral content, antioxidants properties, and antinutrient content of the sample were investigated every 24 h for 5 days. A total of seven bacteria and four fungi consisting of yeasts and moulds were isolated during the study. The microbial loads of bacteria and fungi of the unfermented plantain fruits were 8.0 × 106 ± 0.01 cfu/mL and 14.2 × 104 ± 0.01 sfu/mL respectively. The temperature (ºC), pH and titratable acidity (%) ranged from 25.55-32.50, 4.51-5.50 and 0.99-3.50 respectively. The sample was observed to be colourless all through the fermentation periods. Turbidity of the samples increased during fermentation from 43.50 to 111.00. The data obtained from this work has shown the importance of unripe plantain micro-flora in the production of “Agadagidi”. It is also concluded that consortium of microorganisms inherent within the plantain fruits are involved in plantain fruits fermentation. This information can contribute to a better understanding of the “Agadagidi” production process for a consistent quality beverage.

This work studied the proximate, mineral and phytochemical content of fermented and roasted Tamarind (Tamarindus indica) seed nuts, using standard analytical methods. The seeds were divided into two; one portion was roasted at temperature 85 - 100 oC for 15 mins while the second portion was fermented for 48 hours in the presence of yeast. The proximate analysis of the roasted and fermented samples revealed the values of moisture, ash, crude lipid, Crude protein, crude fibre, carbohydrate and calorific values of the fermented sample were 10.70±0.21 %, 3.06±0.71 %, 2.30±0.19 %, 19.25±0.16 %, 5.75±0.33 %, 58.94±0.23% and 301.29±0.31kcal/100g while values for the roasted sample were 2.00±0.82 %, 3.34±0.53 %, 7.60±0.43 %, 23.63±0.11 %, 5.22±0.74 %, 58.21±0.17 % and 329.08±0.92 kcal/100g respectively. Mineral elements present were K (336.75±0.31 mg/100g), Mg (166.90±0.37 mg/100g), P (106.42±0.65 mg/100g), Na (186.52±0.09 mg/100g) and Ca (10.33±0.15 mg/100g) for the fermented sample and values obtained for K, Mg, P, Na and Ca in roasted sample were 784.95±0.43, 187.65±0.17, 122.38±0.29, 54.36±0.13 and 12.65±0.11 mg/100g respectively. Results of phytochemical content showed that fermented Tamarindus indica contained tannin (64.61±0.43 mg/100 g), saponnins (127.33±0.79 mg/100 g), flavonoid (3.53±0.18 mg/100 g) and alkaloid (23.56±0.37 mg/100 g) while phytochemicals in the roasted sample were 40.97±0.21, 94.69±0.29, 1.96±0.51 and 14.33±0.12 mg/100g for tannins, saponins, flavonoid and alkaloids respectively, and were significantly lower than those in the fermented sample. Correlation analysis indicate a correlation exist between nutritional content of fermented and roasted samples of T. indica. The high crude protein, carbohydrate, calorific value and mineral content in fermented and roasted T. indica seeds indicate that the seeds could be good source of nutrient.

The aim of this research was to assess the antibacterial and antioxidant properties as well as the variation in metabolites of the cell-free supernatant (CFS) produced by lactic acid bacteria (LAB) from local plants: Lactiplantibacillus plantarum ngue16, L. plantarum ng10, Enterococcus durans w3, and Levilactobacillus brevis w6. The tested strains exhibited inhibitory effects against pathogens, including Bacillus cereus, B. subtilis, Cronobacter sakazakii, Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus using the agar spot assay and well diffusion method. The CFS from all four strains displayed antibacterial activity against these pathogens with minimum inhibitory concentration (MIC) values ranging from 3.12 to 12.5 mg/mL and minimal bactericidal concentration (MBC) values ranging from 6.25 to 25.0 mg/mL. Moreover, the CFS demonstrated resilience within specific pH (3–8) and temperature (60–100 °C) ranges and lost its activity when treated with enzymes, such as Proteinase K and pepsin. Furthermore, the CFS exhibited antioxidant properties as evidenced by their ability to inhibit the formation of two radicals (1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) compared to the negative control, De Man, Rogosa, and Sharpe (MRS) broth. The use of proton-based nuclear magnetic resonance (1H-NMR) spectroscopy revealed the presence and quantification of 48 metabolites in both the CFS and MRS broths. Principal Component Analysis (PCA) effectively differentiated between CFS and MRS broth by identifying the specific metabolites responsible for the observed differences. The partial least squares (PLS) model demonstrated a significant correlation between the metabolites in the LAB supernatant and the tested antibacterial and antioxidant activities. Notably, anserine, GABA, acetic acid, lactic acid, uracil, uridine, propylene glycol, isopropanol, serine, histidine, and indol-3-lactate were identified as the compounds contributing the most to the highest antibacterial and antioxidant activities in the supernatant. These findings suggest that the LAB strains investigated have the potential to be utilized in the production of functional foods and the development of pharmaceutical products.

The presence of lactic acid bacteria (LAB) in the vaginal microbiota is fundamental for reproductive health, primarily due to their role in sustaining an acidic pH and providing a defense against urogenital pathogens. The aim of this study was to identify six bacterial isolates (G 4.4 G 13.1, G 21.K.2, G38.0.1, G42.10.2 and G46.M.3) from the vaginal microbiome that had previously demonstrated strong antagonistic activity. The identification of the studied isolates was performed using classical bacteriological methods based on the analysis of their morphological, physiological, and biochemical characteristics. MALDI-TOF MS analysis was conducted in duplicate using the Bruker Microflex® LT/SH smart system (Bruker Daltonics, Bremen, Germany). All tested strains showed limited growth on the surface of MRS agar and produced lenticular or round, milky-white colonies measuring up to 1 mm in diameter within the depth of the agar. Research indicates that the optimal temperature for growth of the studied strains is generally 37℃, whereas strains G 13.1 and G46.M.3 exhibit optimal growth at 33℃. None of the isolates synthesized indole or deaminated arginine. All were negative for oxidase, catalase, urease, and amylase activities, exhibited homofermentative metabolism, and tested positive for gelatinase. The G46.M.3 isolate exhibits lipolytic and caseinolytic activities. The isolates demonstrated the ability to ferment a wide range of carbohydrates. According to MALDI-TOF MS analysis, strain G 4.4 was identified as Lactobacillus delbrueckii subsp. lactis, G 13.1 as Lacticaseibacillus rhamnosus, G 21.K.2 as Lactobacillus delbrueckii subsp. lactis DSM 20355, G 38.0.1 as Lacticaseibacillus paracasei, G 42.10.2 as Lacticaseibacillus rhamnosus, and G 46.M.3 as Enterococcus faecalis 20247_4 CHB. These results enhance the understanding of vaginal microbiota composition and highlight specific LAB with potential probiotic properties. Their demonstrated antagonistic activity suggests a promising role in supporting vaginal and reproductive health.

Probiotics are different kinds of living organisms that have beneficial health effects on humans. Their first origin was from dairy products, but today most probiotic organisms are sources from fermenting fruits and other agricultural products. Lactic acid bacteria (LAB) majorly used as probiotics are groups of Gram-positive, non-sporulating, anaerobic or facultative aerobic cocci or rods, which produce lactic acid as one of the main fermentation products of metabolism from carbohydrates sources. This study investigated the probiotic potential of lactic acid bacteria (LAB) isolated from different types of ogi (pap), a traditional fermented cereal porridge made from maize (Zea mays), millet (Pennisetum typhoideum), and guinea corn (Sorghum bicolor). A total of fifteen ogi samples were collected from Eke Awka market, Nigeria. Using pour-plate method, total bacterial count was done using nutrient agar while total LAB count was done using deMan Rogosa and Sharpe (MRS) agar. Isolates that developed on the plates were characterized and identified using standard biochemical methods. Molecular identification of the isolates were also done using 16s rRNA sequencing. The isolates were evaluated for probiotic properties, including tolerance to NaCl (2–8%), bile salts (0.3%), and phenol (0.1–0.4%). The antimicrobial activity of crude bacteriocins from the LAB isolates was tested against multidrug-resistant clinical specimen namely; Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, Escherichia coli, Salmonella enterica, and Pseudomonas aeruginosa. Results indicated that the total bacterial counts ranged from 3.50 × 104 to 2.30 × 105 CFU/ml, while LAB counts ranged from 1.80 × 104 to 8.90 × 104 CFU/ml in seven of the samples. Five LAB isolates were phenotypically identified as Pediococcus acidilactici, Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus fermentum, and Leuconostoc mesenteroides. Molecular identification via 16S rRNA sequencing confirmed the isolates to be Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus. All LAB isolates exhibited inhibitory effects against at least three pathogens, with Lactiplantibacillus plantarum (J3) showing broad-spectrum activity against all test organisms. The findings showed that traditionally fermented ogi is a valuable source of probiotic LAB which can be harnessed and purified and used against some multidrug resistant organisms to achieve healthy conditions.

Aims: To investigate the effect of food blends (plantain, soybean and ginger) on the blood glucose, lipid profile and haematological indices on streptozotocin induced diabetic rats.
 Methodology: A total of 35 rats of mean body weight 219.07 g separated into7 groups (5 per group) where induced by a single intraperitoneal (I.P) injection of streptozotocin (0.1 g dissolved in 5 ml of freshly prepared sodium citrate buffer 0.1 M, pH 4.5) at a dose of 40 mg/kg body weight after fasting for 12 hours and fed with flours/blends. The flours were produced from plant materials for different treatments/blends (blend A=100% unripe plantain, B=80% unripe plantain, 14% soybean, 6% ginger, C=70% unripe plantain, 26% soybean, 4% ginger, D= 60% unripe plantain, 38% soybean, 2% ginger, E= 50% unripe plantain, 50% soybean) and the phytochemicals and minerals content were determined. Blood glucose was determined at 5 days interval for 25 days. Diabetes was confirmed in rats with blood glucose concentrations >200 mg/dl. After 25 days rats were anaesthetized with chloroform vapour and blood samples collected by cardiac puncture for haematology and lipid profile determination.
 Results: The results showed that unripe plantain, soya beans and ginger in adequate proportion(C=70% unripe plantain, 26% soybean, 4% ginger or D= 60% unripe plantain, 38% soybean, 2% ginger) could help to reduce blood glucose, improve haematological parameters and lipid profile. Significant reduction was observed in the blood glucose level of rats fed blends C and D from 286 to 85 mg/dl and 307 to 90 mg/dl respectively at the end of experiment. These results also demonstrated that the inclusion of ginger at 6% causes rise in blood glucose level. Total cholesterol (TC) increased in all the blends. However, the lowest concentration of TC was observed in blends C and D. The highest packed cell volume (60%) and Haemoglobin (20 g/dl) level observed in rats fed blend C was significantly higher than the normal control fed conventional feeds. The increase in packed cell volume (PCV) (50%) and Hb (17 g/dl) in diabetic rats demonstrated that the formulated blend C was able to raise PCV and Hb above 50% and 17 g/dl (Normal control NC) respectively. Significant increase (P<0.05) in low density lipoprotein cholesterol (LDLc) was also observed in all the blends with blend C having the least (4.0 mg/dl) close to NC (2.0 mg/dl).
 Conclusion: From the results it is evident that blend C will manage and improve the health status of diabetic patients.

This study aimed to investigate the effects of Levilactobacillus brevis, Lacticaseibacillus paracasei, and Lacticaseibacillus rhamnosus strains isolated from Mihalic cheese, also known as “weeping cheese”, on fermentation kinetics, microbial viability, and textural and aromatic properties of the butter matrix. The effects of the isolates were determined on acidification kinetics (Vmax, Tvmax, pHvmax), viability proportion index (VPI), textural parameters (firmness, work of shear, stickiness, work of adhesion), and volatile aroma compounds (GC-MS) formation. This study found that the BLR sample containing Lacticaseibacillus rhamnosus maintained its limited viability under acidic stress conditions despite its high fermentation rate and low pHvmax values. The BLP sample containing Lacticaseibacillus paracasei exhibited high viability due to its low acidification rate and limited pH change. Determining the chemical classes to which the aroma compounds in the BLP sample belonged revealed a composition rich in fatty acids. The BLB sample containing Levilactobacillus brevis produced a high ΔpH value and an aroma profile rich in aldehyde compounds. Examination of the macro-structural properties of the butter samples revealed that the sample containing Lacticaseibacillus rhamnosus, similar to the control sample (BMC), was more compact and rigid during storage. In contrast, samples containing Lacticaseibacillus paracasei and Levilactobacillus brevis had a softer/spreadable texture. These findings demonstrate the potential of lactic acid bacteria isolates from the traditional Mihalic cheese microbiota as biological catalysts for the development/improvement of texture, aroma, and sensory quality in high-fat dairy products and for the industrial production of products modified to meet consumer preferences.

Currently, consumption of spontaneously fermented milks is common in Algeria, making it a feasible source of diverse lactic acid bacteria (LAB) with the potential to be used as adjunct cultures to improve quality and safety of fermented dairy products. In this context, to select eligible indigenous strains which could be applied as bioprotective and/or starter cultures, the present study aimed to characterize the genomic variability, biotechnological potential, and safety of thirty-eight LAB isolated from Algerian dairy and farm sources of western Algeria. The isolates were unequivocally identified by 16S rRNA gene and fingerprint-based methods. The following species were identified: Enterococcus faecium (n = 15), Enterococcus durans (n = 2), Enterococcus hirae (n = 2), Enterococcus lactis (n = 1), Lactiplantibacillus plantarum (n = 6), Lactococcus lactis (n = 4), Levilactobacillus brevis (n = 3), Lacticaseibacillus paracasei (n = 3), Lacticaseibacillus rhamnosus (n = 1), and Pediococcus acidilactici (n = 1). Among the strains, three of them, L. lactis LGMY8, Lb. plantarum LGMY30 and Lb. paracasei LGMY31 were safe and showed some valuable biotechnological properties, such as high acidification, proteolytic activity, EPS production, and inhibition of undesirable bacteria that made them powerful candidates to be used as starter.

Lactic acid bacteria supplementation: A bioprotective approach to mitigating cadmium-induced toxicity and modulating gene expression in murine models

Fermentation is a sustainable bio-preservation technique that can improve the organoleptic quality of fruit juices. Mango juices were fermented by monoculture strains of Lactiplantibacillus plantarum subsp. plantarum (MLP), Lacticaseibacillus rhamnosus (MLR), Lacticaseibacillus casei (MLC), Levilactobacillus brevis (MLB), and Pediococcus pentosaceus (MPP). Volatile compounds were sorbed using headspace solid phase microextraction, separated, and identified with gas chromatography-mass spectrometry. Forty-four (44) volatile compounds were identified. The control, MPP, and MLB had higher amounts of ethyl acetate, ethyl butyrate, 2-hexenal, 2,6-nonadienal, 2,2-dimethylpropanal, β-selinene, γ-gurjunene, α-copaene, and δ-cadinene, while MLC, MLP, and MLR had higher amounts of 2,3-butanedione and a cyclic hydrocarbon derivate. Consumers (n = 80) assessed their overall liking and characterized sensory attributes (appearance, color, aroma, flavor, consistency, acidity, and sweetness) using check-all-that-apply, and penalty analysis (just-about-right). Overall liking was associated with ‘mango color’, ‘pulp’, ‘mango aroma’, ‘sweet’, ‘natural taste’, and ‘mango flavor’ that described the control, MLB, MLC and MPP. Juices MLR and MLP were described as ‘bitter’, ‘sour’, ‘aftertaste’, and ‘off-flavor’. Multivariate analysis revealed relationships between the volatile compounds, mango juices fermented by different lactic acid bacteria, and sensory characteristics. Thus, the type of lactic acid bacteria strains determined the volatile and sensory profile of mango juices.

Innovative enhancement of flavor profiles and functional metabolites composition in Pandanus amaryllifolius through lactic acid bacteria fermentation

Research in metagenomics and metaproteomics can reveal how microbiological interactions in fermented foods contribute to their health benefits. This study examined three types of fermented vegetables: a standard formulation, a probiotic formulation with Lacticaseibacillus rhamnosus GG, and a polyphenol formulation with vitexin from Mung bean seed coat. Measurements were taken at day 0 (after 36 h of fermentation at room temperature) and after 15 days. We applied 16S rRNA sequencing to evaluate microbial diversity and utilized LC-MS/MS to investigate the proteomic profiles of specific genera (Lactobacillus and Weissella) and species (Lacticaseibacillus rhamnosus and Levilactobacillus brevis) of lactic acid bacteria (LAB). All of these taxa demonstrated significant relative abundance between 0 and 15 days of fermentation in our metagenomic analysis. Our findings from principal component analysis and clustering analysis categorically distinguished protein expression patterns at various stages of fermentation. By comparing samples from day 0 to day 15, we identified proteins associated with DNA replication and repair mechanisms, including transcription elongation factor GreA, tRNA pseudouridine synthase B, and helicases. We also observed their roles in protein synthesis, which encompasses oxidoreductases and aspartokinase. Furthermore, we identified strong correlations of specific proteins across the three formulations with antioxidant markers. In conclusion, the results of this study decisively enhance our understanding of the role of the proteins related to specific LAB in fermented foods, highlighting their potential to improve texture, flavor, nutritional quality, and health benefits.

Lactic acid bacteria (LAB) are the most important bacteria in desirable food fermentations, being responsible for the fermentation of sourdough bread, fermented foods and beverages, all fermented milks and fermented vegetables. They play essential roles in the production of all dairy products and is involved in the production of many other fermented foods and beverages, sausages, pickles, etc. This study aimed to produce lactic acid using lactic acid bacteria isolated from pap “akamu” and liquid milk samples. The following procedures were conducted to achieve the objectives of the study, which include sample collection, isolation of lactic acid bacteria (LAB) from samples, screening of LAB for lactic acid production, characterisation of selected lactic acid bacteria, and optimisation of process parameters for lactic acid production. Results from the study showed that the highest lactic acid production (6.39 mg/ml) from milk samples was observed from an isolate from milk sample 2, while for the pap samples, the highest lactic acid production (2.79 mg/ml) was observed from an isolate from pap sample 4. The highest lactic acid producers from the milk and pap samples were identified based on their macroscopic, microscopic and molecular characteristics. The bacteria were identified as Lactobacillus paracasei (sample milk 2) and Levilactobacillus brevis (sample pap 4). Biochemical characterisation indicated the metabolic capabilities of these isolates, including acidifying properties, enzyme production, and fermentation abilities. The highest production of lactic acid by co-cultures of Lactobacillus paracasei and Levilactobacillus brevis was observed after 96 h of incubation. Enhanced lactic acid yield by the co-cultures was observed at pH 5.5 (8.6 mg/ml), while the lactic acid production decreased at a higher pH. The lactic acid concentration increased to the optimum lactic acid value (8.60 mg/mL) at 35°C, then decreased at 45°C. Maximum lactic acid production of 11.2mg/ml was observed at 200 rpm, the least of 4.9 mg/ ml was observed at zero or no agitation. The lactic acid production increased gradually with increasing inoculum size up to the maximum value (10.7 mg/mL) at 5% inoculum size. Lactic acid actually had the highest peak area, retention time and concentration in the GCFID chromatogram, while the other components had low values, further revealing the successful extraction of the lactic compound. The results of the present study indicated that the co-cultures of Lactobacillus paracasei (milk 2) and Levilactobacillus brevis (pap 4) isolated from milk and akamu, respectively, hold significant potential for lactic acid production.