Fruit cracking is a common physiological disease. Many fruits such as tomato, sweet cherry, apple, jujube, pomegranate, and litchi are liable to crack, causing considerable economic loss and agricultural resources waste. The mechanisms of fruit cracking are comprehensive. Some correlations have been observed between susceptibility of fruit cracking and some fruit traits (genetic, fruit size, fruit shape, fruit growth rate, water content, fruit skin characteristics, related gene expression, etc). Also, environmental condition (temperature, light, rainfall, etc) and orchard management (irrigation, sun-shade, mineral, growth regulator, etc) can influence fruit cracking. Here, progress in studies on fruit cracking is reviewed to provide a reference for prevention and control of fruit cracking.
Fruit ; Litchi ; Lycopersicon esculentum

Litchi (Litchi chinensis Sonn.) and longan (Dimocarpus longan Lour.) fruits have a succulent and white aril with a brown seed and are becoming popular worldwide. The two fruits have been used in traditional Chinese medicine as popular herbs in the treatment of neural pain, swelling, and cardiovascular disease. The pericarp and seed portions as the by-products of litchi and longan fruits are estimated to be approximately 30% of the dry weight of the whole fruit and are rich in bioactive constituents. In the recent years, many biological activities, such as tyrosinase inhibitory, antioxidant, anti-inflammatory, immunomodulatory, anti-glycated, and anti-cancer activities, as well as memory-increasing effects, have been reported for the litchi and longan pericarp and seed extracts, indicating a potentially significant contribution to human health. With the increasing production of litchi and longan fruits, enhanced utilization of the two fruit by-products for their inherent bioactive constituents in relation to pharmacological effects is urgently needed. This paper reviews the current advances in the extraction, processing, identification, and biological and pharmacological activities of constituents from litchi and longan by-products. Potential utilization of litchi and longan pericarps and seeds in relation to further research is also discussed.
Fruit ; chemistry ; Humans ; Litchi ; chemistry ; Phytochemicals ; analysis ; Plant Extracts ; pharmacology ; Sapindaceae ; chemistry ; Seeds ; chemistry

BACKGROUND/OBJECTIVES: Natural products or active components with a protective effect against oxidative stress have attracted significant attention for prevention and treatment of degenerative disease. Oligonol is a low molecular weight polyphenol containing catechin-type monomers and oligomers derived from Litchi chinensis Sonn. We investigated the protective effect and its related mechanism of oligonol against oxidative stress. MATERIALS/METHODS: Oxidative stress in C6 glial cells was induced by hydrogen peroxide (H2O2) and the protective effects of oligonol on cell viability, nitric oxide (NO) and reactive oxygen species (ROS) synthesis, and mRNA expression related to oxidative stress were determined. RESULTS: Treatment with oligonol inhibited NO and ROS formation under cellular oxidative stress in C6 glial cells. In addition, it recovered cell viability in a dose dependent-manner. Treatment with oligonol also resulted in down-regulated mRNA expression related to oxidative stress, nuclear factor kappa-B (NF-kappaB) p65, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS), compared with the control group treated with H2O2. In particular, expression of NF-kappaB p65, COX-2, and iNOS was effectively reduced to the normal level by treatment with 10 microg/mL and 25 microg/mL of oligonol. CONCLUSIONS: These results indicate that oligonol has protective activity against oxidative stress-induced inflammation. Oligonol might be a promising agent for treatment of degenerative diseases through inhibition of ROS formation and NF-kappaB pathway gene expression.
Biological Products ; Cell Survival ; Cyclooxygenase 2 ; Gene Expression ; Hydrogen Peroxide ; Inflammation* ; Litchi ; Molecular Weight ; Neuroglia* ; NF-kappa B ; Nitric Oxide ; Nitric Oxide Synthase Type II ; Oxidative Stress ; Reactive Oxygen Species ; RNA, Messenger

BACKGROUND/OBJECTIVES: Oligonol, mainly found in lychee fruit, is an antioxidant polyphenolic compound which has been shown to have anti-inflammatory and anti-cancer properties. The detailed mechanisms by which oligonol may act as an anti-aging molecule have not been determined. MATERIALS/METHODS: In this study, we evaluated the ability of oligonol to modulate sirtuin (SIRT) expression in human lung epithelial (A549) cells. Oligonol was added to A549 cells and reactive oxygen species production, mitochondrial superoxide formation, and p21 protein levels were measured. Signaling pathways activated upon oligonol treatment were also determined by western blotting. Furthermore, the anti-aging effect of oligonol was evaluated ex vivo in mouse splenocytes and in vivo in Caenorhabditis elegans. RESULTS: Oligonol specifically induced the expression of SIRT1, whose activity is linked to gene expression, metabolic control, and healthy aging. In response to influenza virus infection of A549 cells, oligonol treatment significantly up-regulated SIRT1 expression and down-regulated viral hemagglutinin expression. Oligonol treatment also resulted in the activation of autophagy pathways and the phosphorylation of AMP-activated protein kinase (AMPK). Furthermore, oligonol-treated spleen lymphocytes from old mice showed increased cell proliferation, and mRNA levels of SIRT1 in the lungs of old mice were significantly lower than those in the lungs of young mice. Additionally, in vivo lethality assay revealed that oligonol extended the lifespan of C. elegans infected with lethal Vibrio cholerae. CONCLUSIONS: These data demonstrated that oligonol may act as an anti-aging molecule by modulating SIRT1/autophagy/AMPK pathways.
Aging ; AMP-Activated Protein Kinases ; Animals ; Autophagy ; Blotting, Western ; Caenorhabditis elegans ; Cell Proliferation ; Fruit ; Gene Expression ; Hemagglutinins, Viral ; Humans ; Litchi ; Lung ; Lymphocytes ; Mice ; Orthomyxoviridae ; Phosphorylation ; Reactive Oxygen Species ; RNA, Messenger ; Spleen ; Superoxides ; Vibrio cholerae