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Chirality is a widespread phenomenon in nature and in living organisms and plays an important role in living systems. The sensitive discrimination of chiral molecular enantiomers remains a challenge in the fields of chemistry and biology. Establishing a simple, fast, and efficient strategy to discriminate the spatial configuration of chiral molecular enantiomers is of great significance. Chiral perovskite nanocrystals (PNCs) have attracted much attention because of their excellent optical activity. However, it is a challenge to prepare perovskites with both chiral and fluorescence properties for chiral sensing. In this work, we synthesized two chiral fluorescent perovskite nanocrystal assembly (PNA) enantiomers by using l- or d-phenylalanine (Phe) as chiral ligands. PNA exhibited good fluorescence recognition for l- and d-proline (Pro). Homochiral interaction led to fluorescence enhancement, while heterochiral interaction led to fluorescence quenching, and there is a good linear relationship between the fluorescence changing rate and l- or d-Pro concentration. Mechanism studies show that homochiral interaction-induced fluorescence enhancement is attributed to the disassembly of chiral PNA, while no disassembly of chiral PNA was found in heterochiral interaction-induced fluorescence quenching, which is attributed to the substitution of Phe on the surface of chiral PNA by heterochiral Pro. This work suggests that chiral perovskite can be used for chiral fluorescence sensing; it will inspire the development of chiral nanomaterials and chiral optical sensors.

This study was conducted to recover edible bird’s nest (EBN) hydrolysates from different grades of EBN, including the industrial by-products, using enzymatic treatment. The nutrient, physicochemical properties and antioxidant activities of the recovered hydrolysates at different hydrolysis times were evaluated. Results showed that the recovery yield of enzymatic hydrolysis was above 89 % for all grades of EBN and the degree of hydrolysis increased over time. Nitrite content (0.321–0.433 mg/L) was below the permissible tolerance level for all samples. Interestingly, the antioxidant activities (DPPH and ABTS scavenging activities and ferric reducing antioxidant powder (FRAP) activity) were significantly higher (P≤ 0.05) in hydrolysates recovered from EBN by-products (EBNhCand EBNhD) as compared to the high grade EBN hydrolysates (EBNhAand EBNhB). The in-vitroprobiotic activity of EBN and its hydrolysates were examined using the probiotic bacterium Lactobacillus plantarum. Evidently, EBN by-products hydrolysate (EBNhD) recorded the highest number of L. plantarum(1.1 × 1011CFU/mL), indicating that low grade EBN has the potential as prebiotic material that promotes probiotic activity. This study demonstrated the concept of using EBN by-products hydrolysates for various applications, such as functional ingredients with enhanced bioactivities, to improve its economic value.

Gastrointestinal (GI) complications, that severely impact patient quality of life, are a common occurrence in patients with Parkinson’s disease (PD). Damage to enteric neurons and the accumulation of alpha-synuclein in the enteric nervous system (ENS) are thought to contribute to this phenotype. Copper or iron chelators, that bind excess or labile metal ions, can prevent aggregation of alpha-synuclein in the brain and alleviate motor-symptoms in preclinical models of PD. We investigated the effect of ATH434 (formally PBT434), a small molecule, orally bioavailable, moderate-affinity iron chelator, on colonic propulsion and whole gut transit in A53T alpha-synuclein transgenic mice. Mice were fed ATH434 (30 mg/kg/day) for either 4 months (beginning at ∼15 months of age), after the onset of slowed propulsion (“treatment group”), or for 3 months (beginning at ∼12 months of age), prior to slowed propulsion (“prevention group”). ATH434, given after dysfunction was established, resulted in a reversal of slowed colonic propulsion and gut transit deficits in A53T mice to WT levels. In addition, ATH434 administered from 12 months prevented the slowed bead expulsion at 15 months but did not alter deficits in gut transit time when compared to vehicle-treated A53T mice. The proportion of neurons with nuclear Hu+ translocation, an indicator of neuronal stress in the ENS, was significantly greater in A53T than WT mice, and was reduced in both groups when ATH434 was administered. ATH434 can reverse some of the GI deficits and enteric neuropathy that occur in a mouse model of PD, and thus may have potential clinical benefit in alleviating the GI dysfunctions associated with PD.

Kombucha is produced by fermenting sweetened tea with symbiotic culture of bacteria and yeast (SCOBY). Kombucha is slightly sweet and acidic tea beverage that is popular all over the world due to its refreshing taste and health-promoting active metabolites formed during the fermentation process. Sucrose-sweetened tea is the traditional substrate for kombucha fermentation. However, due to consumers’ demand as well as availability of resources, various alternative substrates, such as honey, molasses and coffee, have been used in the production of kombucha over time to promote additional health benefits. Aside from that, kombucha fermentation supplementation, such as with herbs, bee pollen, and lactic acid bacteria, have also been used to develop new novel kombucha, to value-add the biological activities and sensory properties. The activity of Komagataeibacterspp. bacteria results in the formation of a polymeric cellulose pellicle during the kombucha fermentation process. The cellulose produced has a wide range of application in a variety of fields. In this review, conventional and alternative fermentation methods were reviewed to better understand the development of kombucha.