Effects of Cultivation Month and Genetic Background on Phenolic Content of Citrus tachibana Peel

Investigation of changes in non-traditional indices of maturation in Navel orange peel and juice using GC-MS and LC-QTOF/MS

Changes in non-traditional indices of maturity, such as flavonoids and volatile compounds, during maturation were studied in Navel orange. Navel oranges were obtained at four stages of maturation, and non-volatile and volatile compounds in the peel and juice were analysed using liquid chromatography coupled with a quadrupole time-of-flight detector (LC-QTOF/MS) and gas chromatography with mass spectrometry and a flame ionisation detector (GC-MS/FID), respectively. Twenty-eight non-volatile and 62 volatile compounds in the peel as well as 22 non-volatile and 11 volatile compounds in the juice were found to have significant changes (p < 0.05) in abundances during maturation. Notably, most flavonoids (e.g. narirutin) and limonoids (e.g. nomilin) showed decreasing abundances during maturation. For volatile compounds, majority of detected alcohols peaked in abundances during middle maturation stages, while almost all detected aldehydes peaked at full maturity. Most terpenes peaked at earlier maturation stages in juice extracts compared to peel oil extracts. This comprehensive study could facilitate selection of Navel oranges for the extraction of valuable bioactive or flavour contributing compounds that are of interest to fragrance, flavour and nutraceutical industries.

Evaluation of dynamic changes in the bioactive components in Citri Reticulatae Pericarpium (Citrus reticulata 'Chachi') under different harvesting and drying conditions

BACKGROUND

The Citrus reticulata 'Chachi' pericarp (CRCP) is one cultivar of Citri Reticulatae Pericarpium (Chenpi), which is widely applied in medicine and food. To determine the potential value of CRCP harvested at different stages and subjected to different drying processes, the dynamic changes in the bioactive components were profiled and evaluated in this study.

RESULTS

The contents of all non-volatile components, i.e. synephrine, limonin, phenolic acids and flavonoids, decreased with delayed harvest time. The volatiles thujene, α-pinene, β-pinene, d-citronellol, d-citronellal, decanal, linalool, geraniol, l-cis-carveol, terpinen-4-ol, α-terpineol, carvacrol, perillaldehyde, methyl 2-(methylamino)benzoate and d-limonene were considered the characteristic components for distinguishing CRCP harvested at different stages. Phenolic acids, synephrine and limonin were stable at different drying temperatures; however, high-temperature drying at 60 °C induced a significant transformation in the flavonoids (especially polymethoxyflavones) and volatile substances in CRCP.

CONCLUSIONS

The results suggested that most of the bioactive components declined with the growth of Citrus reticulata 'Chachi'. And it is believed that the fresh peel should be naturally sun-dried or dried at low temperature (30 or 45 °C) rather than at high temperature (60 °C) to prevent excessive loss of nutrients. © 2020 Society of Chemical Industry.

The Anti-Aging Potential of Extracts from Chaenomeles sinensis

The Chaenomeles sinensis fruit is used as an effective antitussive agent, analgesic, and diuretic in traditional Chinese medicine. It has been reported that C. sinensis fruit extracts have antimicrobial and anti-inflammatory effects. However, there are very few reports about the effects of C. sinensis extracts on skin. In this study, we investigated the effect of C. sinensis extracts on skin aging. The results of in vitro assays showed that whole fruit extracts of C. sinensis had superoxide dismutase (SOD)-like activity and inhibited the activity of dermal extracellular matrix proteases: Elastase and collagenase. The inhibitory effect of the whole fruit (containing seeds) extract on elastase activity was higher than that of the sarcocarp (seeds removed) extract. Further, the sarcocarp extract showed a higher level of SOD-like activity and a greater inhibitory effect on collagenase activity than the whole fruit extract. In particular, among the three activities studied, the sarcocarp extract showed the most significant inhibitory effect on collagenase activity at low concentrations. The polyphenol-rich fraction obtained from the sarcocarp showed significant collagenase inhibition. Based on these results, we concluded that phenolic compounds from C. sinensis sarcocarp have the potential to protect against skin aging through anti-collagenase activity.