Kombucha, one of the ordinary fermented beverages consumed worldwide, is produced by fermenting tea and sugar with a symbiotic culture of bacteria and yeasts or so-called SCOBY. Kombucha can be made from different types of tea, such as black, green, white, red, and oolong teas, yielding various health benefits and properties. Several species of bacteria and yeasts are involved in the fermentation process, which generates many beneficial compounds, such as polyphenols, organic acids, amino acids, vitamins, minerals, organic nitrogens, and hydrolytic enzymes, which have significant health effects and therapeutic properties, such as antioxidant, anti-inflammatory, anticancer, and antimicrobial properties. This review describes recent research on kombucha fermentation, the microbial community in SCOBY, the chemical composition of kombucha, and its health benefits. The adverse effects and prospects of kombucha production were also discussed.

Several raw materials have been used as partial supplements or entire replacements for the main ingredients of kombucha to improve the biological properties of the resulting kombucha beverage. This study used pineapple peels and cores (PPC), byproducts of pineapple processing, as alternative raw materials instead of sugar for kombucha production. Kombuchas were produced from fusions of black tea and PPC at different ratios, and their chemical profiles and biological properties, including antioxidant and antimicrobial activities, were determined and compared with the control kombucha without PPC supplementation. The results showed that PPC contained high amounts of beneficial substances, including sugars, polyphenols, organic acids, vitamins, and minerals. An analysis of the microbial community in a kombucha SCOBY (Symbiotic Cultures of Bacteria and Yeasts) using next-generation sequencing revealed that Acetobacter and Komagataeibacter were the most predominant acetic acid bacteria. Furthermore, Dekkera and Bacillus were also the prominent yeast and bacteria in the kombucha SCOBY. A comparative analysis was performed for kombucha products fermented using black tea and a fusion of black tea and PPC, and the results revealed that the kombucha made from the black tea and PPC infusion exhibited a higher total phenolic content and antioxidant activity than the control kombucha. The antimicrobial properties of the kombucha products made from black tea and the PPC infusion were also greater than those of the control. Several volatile compounds that contributed to the flavor, aroma, and beneficial health properties, such as esters, carboxylic acids, phenols, alcohols, aldehydes, and ketones, were detected in kombucha products made from a fusion of black tea and PPC. This study shows that PPC exhibits high potential as a supplement to the raw material infusion used with black tea for functional kombucha production.

The potential benefits of natural plant extracts have received attention in recent years, encouraging the development of natural products that effectively treat various diseases. This is the first report on establishing callus and cell suspension cultures of Rhinacanthus nasutus (L.) Kurz. A yellow friable callus was successfully induced from in vitro leaf explants on Murashige and Skoog medium supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid and 1 mg/L 1-naphthalene acetic acid. A selected friable callus line was used to establish the cell suspension culture with the same medium. The antioxidant assays showed that the leaf- and ethanolic-suspension-cultured cell (SCC) extracts exhibited high antioxidant potential. In addition, the in vitro cytotoxicity revealed by the MTT assay demonstrated potent antiproliferative effects against the oral cancer cell lines ORL-48 and ORL-136 in a dose-dependent manner. Several groups of compounds, including terpenoids, phenolics, flavonoids, quinones, and stilbenes, were identified by UHPLC–QToF–MS, with the same compounds detected in leaf and SCC extracts, including austroinulin, lucidenic acid, esculetin, embelin, and quercetin 3-(2″-p-hydroxybenzoyl-4″-p-coumarylrhamnoside). The present study suggests the value of further investigations for phytochemical production using R. nasutus cell suspension culture.

The optimum fermentation conditions for ethanol production from sweet sorghum juice (SSJ) by the thermotolerant yeast Saccharomyces cerevisiae DBKKUY-53 were determined using a statistical experimental design. Based on the Plackett–Burman design (PBD), yeast cell concentration, sugar concentration, and yeast extract were the significant independent fermentation factors affecting the ethanol production from SSJ at 37 °C by S. cerevisiae DBKKUY-53. These significant factors were optimized using response surface methodology (RSM) based on a central composite design (CCD). The result revealed that the optimum conditions for ethanol fermentation were 7.85 × 107 cells/mL yeast cell concentration, 247 g/L sugar concentration, and 9.99 g/L yeast extract. Verification of the ethanol production using the optimum conditions revealed that the maximum ethanol concentration of 99.75 g/L and the productivity of 2.77 g/L/h were achieved. When the ethanol production was carried out in a 2 L fermentor under optimum conditions, the ethanol concentration was 101.81 g/L and the productivity was 2.83 g/L/h. This finding suggested that the thermotolerant yeast S. cerevisiae DBKKUY-53 has excellent potential for commercial ethanol production at high temperatures.

This study describes the in vitro propagation and ex vitro acclimatization of Philodendron erubescens pink princess, one of the most popular ornamental variegated foliage plants. For shoot proliferation, the protocorm-like bodies of the Philodendron pink princess were cultured on solid Murashige and Skoog (MS) media supplemented with 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA) at different concentrations. The results revealed that supplementation with BAP alone at a concentration of 1.0 mg/L yielded the maximum number of shoots and leaves. Furthermore, the application of BAP at 1.0 mg/L significantly enhanced the shoot proliferation of Philodendron pink princess when grown in liquid MS medium, yielding 11.2 shoots/explant and 4.7 leaves/explant. When the established microshoots were subjected to root induction using solid MS media supplemented with different kinds and concentrations of auxins, indole-3-butyric acid (IBA) at 3 mg/L resulted in the highest number of roots (3.2 roots/explant) and longest root length (1.9 cm). Three supporting materials, i.e., peat moss, vermiculite, and perlite, were used as planting media for the ex vitro acclimatization of the Philodendron pink princess plantlets. The results demonstrated that the in vitro plantlets acclimatized and exhibited a relatively high survival frequency in all planting media without morphological abnormalities. Peat moss outperformed all other types of planting media in terms of sustaining the vegetative growth of the plantlets. In the future, the approach established in this study could be employed for the extensive production of Philodendron pink princess.