ABSTRACT
This study aimed to improve the anticancer effect of Cordyceps militaris herbal extract (CME) on breast cancer cells with hyaluronic acid (HYA) surface-decorated lipid polymer hybrid nanoparticles (LPNPs) and evaluate the applicability of a synthesized poly(glycerol adipate) (PGA) polymer for LPNP preparation. Firstly, cholesterol- and vitamin E-grafted PGA polymers (PGA-CH and PGA-VE, respectively) were fabricated, with and without maleimide-ended polyethylene glycol. Subsequently, CME, which contained an active cordycepin equaling 9.89% of its weight, was encapsulated in the LPNPs. The results revealed that the synthesized polymers could be used to prepare CME-loaded LPNPs. The LPNP formulations containing Mal-PEG were decorated with cysteine-grafted HYA via thiol-maleimide reactions. The HYA-decorated PGA-based LPNPs substantially enhanced the anticancer effect of CME against MDA-MB-231 and MCF-7 breast cancer cells by enhancing cellular uptake through CD44 receptor-mediated endocytosis. This study demonstrated the successful targeted delivery of CME to the CD44 receptors of tumor cells by HYA-conjugated PGA-based LPNPs and the new application of synthesized PGA-CH- and PGA-VE-based polymers in LPNP preparation. The developed LPNPs showed promising potential for the targeted delivery of herbal extracts for cancer treatment and clear potential for translation in in vivo experiments.
ABSTRACT
The occurrence of the postharvest physiological disorder of dark spots on the peel of the ripened "Khai" banana has led to a reduction in its commercial value. The objective of the present study was to investigate the development mechanisms of senescence dark spots of the "Khai" (Musa AA group) banana peel in relation to chlorophyll degradation and stomata cell death. Freshly harvested bananas (commercial mature green stage) were let to ripened at 25 ± 2°C (90%-95% RH). Peel color, senescent spots, DNA degradation, chlorophyll content, chlorophyll-degrading enzyme activities were assessed. The senescent dark spots developed on the ripened bananas right after 6 days of storage, which coincided with remarkably increased DNA degradation, and a rapid decreased of hue angle value and total chlorophyll content which indicated the chlorophyll degradation. The activities of chlorophyllase, chlorophyll-degrading peroxidase and pheophytinase increased gradually to the highest point where the chlorophyll content drastically reduced and the appearance of the dark spots was first recorded after 6 days of storage. These dark spots were observed to be surrounded with a bright luminescent ring of hypermodified fluorescent chlorophyll catabolites (FCCs), the product of chlorophyll breakdown. Additionally, the scanning electron microscope (SEM) revealed that the dark spots were found to have originated from the collapsed cells around the stomata of the ripened banana peel whereby the chlorophyll was entirely diminished. PRACTICAL APPLICATIONS: This research revealed the senescent dark spot development mechanisms of the "Khai" banana peel. The dark spot development symptom on the banana peel surface was caused by the senescence and cell death of the relevant stomata, further associated with chlorophyll degradation. Therefore, any further research into minimizing the dark spot symptom must focus on preventing or delaying stomata senescence and cell death.
Subject(s)
Musa , Cell Death , ChlorophyllABSTRACT
This study was carried out to investigate the combined effects of vacuum packaging (VP) and cold shock (CS) of asparagus on lignification during storage at 4°C. Physiological and biochemical changes were analyzed. The VP + CS treatment reduced fresh weight loss and color change and prevented the increment of spear toughness the most compared to VP, CS, and control. Also, the VP + CS was most effective in suppressing the activities of lignin biosynthesis enzymes, including phenylalanine ammonia-lyase, cinnamyl-alcohol dehydrogenase, and peroxidase, thereby delaying lignin formation. In addition, the combined treatment delayed ethylene production peak and the reduction of total phenolic content. These results suggest that VP + CS may maintain eating quality of asparagus spears through delay of lignification. PRACTICAL APPLICATIONS: This study mainly focused on reducing lignification of asparagus spears using VP + CS, which is safe, eco-friendly, affordable, and practical. Our results showed that VP + CS significantly delayed lignification. Thus, VP + CS represents a promising postharvest handling approach for reducing the lignin content of asparagus, to preserve its integrity, and improve stability during shipment. This prospective technique will eliminate the use of chemical alternatives to prolong the storage life and maintain the quality of spears.
