Adhesion capacity is considered one of the selection criteria for probiotic strains. The purpose of this study was to determine the adhesion properties of two candidate probiotics, Lactobacillus plantarum Dad-13 and Lactobacillus plantarum Mut-7. The evaluation included the hydrophobicity of the cell surface using microbial adhesion to hydrocarbons (MATH), autoaggregation, and the adhesion of L. plantarum Dad-13 and L. plantarum Mut-7 to the intestinal mucosa of Sprague Dawley rat, followed by genomic analysis of the two L. plantarum strains. L. plantarum Dad-13 and L. plantarum Mut-7 showed a high surface hydrophobicity (78.9% and 83.5%) and medium autoaggregation ability (40.9% and 57.5%, respectively). The exposure of both isolates to the surface of the rat intestine increased the total number of lactic acid bacteria on the colon compartment, from 2.9 log CFU/cm² to 4.4 log CFU/cm² in L. plantarum Dad-13 treatment and to 3.86 log CFU/cm² in L. plantarum Mut-7 treatment. The results indicate the ability of two L. plantarum to attach to the surface of the rat intestine. The number of indigenous E. coli in the colon also decreased when the compartment was exposed to L. plantarum Dad-13 and Mut-7, from 2.9 log CFU/cm² to 1 log CFU/cm². Genomic analysis revealed that both strains have genes related to adhesion properties that could play an important role in increasing the adherence of probiotics to the intestinal mucosa such as gene encoding fibronectin-binding protein, chaperonin heat shock protein 33 (Hsp33), and genes related to the capsule and cell wall biosynthesis. Based on these findings, we believe that L. plantarum Dad-13 and L. plantarum Mut-7 have adhesion properties to the intestinal mucosa in the rat intestine model system. The present research will be essential to elucidate the molecular mechanism associated with adhesion in our two probiotic strains.

Cocoa bean fermentation is an important process in the manufacturing of cocoa products. It involves microbes, such as lactic acid bacteria, yeast, and acetic acid bacteria. The presence of mold in cocoa bean fermentation is undesired, as it reduces the quality and may produce mycotoxins, which can cause poisoning and death. Aspergillus niger is a fungus that produces ochratoxin A, which is often found in dried agricultural products such as seeds and cereals. In this study, we applied indigenous Candida famata HY-37, Lactobacillus plantarum HL-15, and Acetobacter spp. HA-37 as starter cultures for cocoa bean fermentation. We found that the use of L. plantarum HL-15 individually or in combination Candida famata HY-37, Lactobacillus plantarum HL-15, and Acetobacter spp. HA-37 as a starter for cocoa bean fermentation can inhibit the growth of A. niger YAC-9 and the synthesis of ochratoxin A during fermentation and drying. With biological methods that use indigenous Lactobacillus plantarum HL-15 individually or in combination with Candida famata HY-37 and Acetobacter spp. HA-37, we successfully inhibited contamination by ochratoxin-A-producing fungi. Thus, the three indigenous microbes should be used in cocoa bean fermentation to inhibit the growth of fungi that produce mycotoxins and thus improve the quality.

Malnutrition, which consists of undernutrition and overnutrition, is associated with gut microbiota composition, diet, and sociodemographic factors. Undernutrition is a nutrient deficiency that that should be identified to prevent other diseases. In this study, we evaluate the gut microbiota composition in undernourished children in association with diet and sociodemographic factors. We observed normal children (n= 20) and undernourished children (n= 20) for ten days in Lombok and Yogyakarta. Diet, sociodemographic factors, and medical records were recorded using food records, screening forms, and standard household questionnaires. Gut microbiota analysis was performed using 16S rRNA gene sequencing targeting the V3–V4 region. The result showed that the undernourished group had lower energy intake. In addition, the undernourished group had lower quality of medical records, parent knowledge, education, and exclusive breastfeeding. Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, and Verrucomicrobia were significantly different between normal and undernourished children. Based on LefSe, we determined that Akkermansia is a biomarker for undernourished children. In conclusion, diet and sociodemographic factors affect the gut microbiota composition of undernourished children.

Cocoa fermentation is an essential process that produces flavor precursors. However, many small farmers in Indonesia directly dry their cocoa beans without fermentation due to low yield and long fermentation time, resulting in fewer flavor precursors and cocoa flavor. Therefore, this study aimed to enhance the flavor precursors, particularly free amino acids and volatile compounds, of unfermented cocoa beans by hydrolysis, using bromelain. Unfermented cocoa beans were previously hydrolyzed with bromelain at concentrations of 3.5, 7, and 10.5 U/mL for 4, 6, and 8 h, respectively. An analysis of enzyme activity, degree of hydrolysis, free amino acids, reducing sugar, polyphenols, and volatile compounds was then conducted using unfermented and fermented cocoa beans as negative and positive controls, respectively. The results showed that the highest degree of hydrolysis was 42.95% at 10.5 U/mL for 6 h, although it was not significantly different from the hydrolysis at 3.5 U/mL for 8 h. This indicates a higher reducing sugar and lower polyphenols content than unfermented cocoa beans. There was also an increase in free amino acids, especially hydrophobic amino acids, such as phenylalanine, valine, leucine, alanine, and tyrosine, and desirable volatile compounds, such as pyrazines. Therefore, this suggests that hydrolysis with bromelain increased the flavor precursors and cocoa-bean flavors.

Black soybeans contain high antioxidant compounds such as isoflavone but mainly in glucoside form, with low antioxidant activities. Fermentation by lactic acid bacteria (LAB) can enhance the antioxidant properties, but its ability is strain-dependent. This study aims to study the ability of Indonesian indigenous LAB, Lactiplantibacillus plantarum WGK 4, Streptococcus thermophilus Dad 11, and Lactiplantibacillus plantarum Dad 13, to enhance the antioxidant properties during black soy milk fermentation. Fermentation was carried out at 37 °C for 24 h. Viable cell, acid production, Folin–Ciocalteu assay, antioxidant activity (DPPH), isoflavone aglycone daidzein and genistein, and β-glucosidase activity were measured every six hours. All LAB strains could grow well during the fermentation of black soy milk. Lactiplantibacillus plantarum WGK 4 produced the highest acid (1.50%). All three LAB strains could enhance antioxidant activity (DPPH) from 24.90% to 31.22–38.20%, followed by increased isoflavone aglycone. All strains could increase daidzein and genistein content, ranging from 61% to 107% and 81% to 132%, respectively. All three Indonesian indigenous LAB enhanced antioxidant properties of black soy milk relatively at the same level and potentially could be used as a starter culture of black soy milk fermentation.