Effect of Lactic Fermentation and Spray Drying Process on Bioactive Compounds from Ngoc Linh Ginseng Callus and Lactobacillus plantarum Viability

Abstract

Ngoc Linh ginseng is one of the most valuable endemic medicinal herbs in Vietnam. In this study, Ngoc Linh ginseng callus was fermented by Lactobacillus plantarum ATCC 8014 (at 6, 7, and 8 log CFU/ml) to evaluate the extraction efficiency of bioactive compounds. The post-fermentation solution was spray-dried using maltodextrin with or without Stevia rebaudiana (3% and 6% v/v) as the wall material. Bioactive compounds such as polyphenols, polysaccharides, and total saponins, and L. plantarum viability during fermentation and after spray-drying, as well as under simulated gastric digestion, were evaluated in this study. The results showed that probiotic density had a significant effect on bioactive compounds, and L. plantarum at 8 log CFU/ml showed the best results with a short fermentation time compared to other tests. The total content of polyphenols, polysaccharides, and saponins reached 5.16 ± 0.18 mg GAE/g sample, 277.2 ± 6.12 mg Glu/g sample, and 4.17 ± 0.15 mg/g sample, respectively after 20 h of fermentation at the initial density of L. plantarum (8 log CFU/ml). Although there was no difference in the particle structure of the preparation, the microencapsulation efficiency of the bioactive compound in the samples containing S. rebaudiana was higher than that with only maltodextrin. The study also indicated that adding S. rebaudiana improved the viability of L. plantarum in gastric digestion. These results showed that S. rebaudiana, a component stimulating probiotic growth, combined with maltodextrin as a co-prebiotic, improved the survival rate of L. plantarum in simulated gastric digestion.

Effect of Microwaves, Ultrasound, Enzyme, and Lactic Bacteria on Extraction Efficiency of Bioactive Compounds from Agarwood Leaves (Aquilaria spp.)

“…This could be due to the bioactive compounds, after being released from cells by the fermentation process, were then affected by temperature, light, and external environment, and were oxidized. Furthermore, the presence of lactic acid bacteria contributed to simple phenolic conversion and reduction of phenolic compounds of high molecular weight, decreasing the content of bioactive substances during fermentation [13]. The flavonoid content tended to decrease during fermentation, but this reduction was not significant (p<0.05) (Figure 9).…”

“…The total polysaccharide content was determined following the procedure outlined by Dong et al [13], with some modifications. Initially, 1 mL of the sample was combined with 5 mL of 96% ethanol (v/v) and allowed to cool to 40°C for 24 h. The precipitate was collected, dissolved, and mixed with 10 mL of hot water at 70°C.…”