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Many studies have shown that flavonoids have various physiological activities such as anti-inflammatory, antibacterial, anti-cancer, and hepatoprotective activities. Meanwhile, its hydrophilic nature has led to low absorption into the body and the limitations of its bioactivity. Many acylated flavonoids and their bioactivities, including those obtained as natural compounds and those synthesized biochemically or chemically, have been reported to improve their bioavailability. This review focuses on the recent developments of the cancer chemopreventive activity of acylated flavonoids. Novel acylated flavonoids have been identified from nature since 2015, and many of them have shown high cytoprotective and anti-inflammatory effects by acylation of glycosyl residues. A large number of acylated flavonoids have been synthesized by enzyme-catalyzed and chemical methods, and their bioactivity has been evaluated. The introduction of acyl groups in the sugar residues showed higher antioxidant activity with increased lipophilicity and improved anti-inflammatory and cytoprotective effects and the ability of apoptosis induction in cancer cells. In contrast, introducing acyl groups into the hydroxy groups of aglycones resulted in less antioxidant activity but improved cancer proliferation inhibition and anti-inflammatory effects. Acylation of flavonoids tends to increase their bioactivity over the parent compound. The increased bioactivity by acylation can be attributed to increased lipophilicity and improved membrane permeability. Acylated flavonoids are one of a group of promising compounds that have cancer chemopreventive effects. However, the study of ADME (Absorption, Distribution, Metabolism, Excretion) will be essential to elucidate the relationship between acylation of flavonoids and the improvement of their bioactivity.

Background Weaning is one of the major factors that cause stress and intestinal disease in piglets. Protocatechuic acid (PCA) is an active plant phenolic acid which exists in Chinese herb, Duzhong (Eucommia ulmoides Oliver), and is also considered as the main bioactive metabolite of polyphenol against oxidative stress and inflammation. This study aimed to investigate the effect of PCA on growth performance, intestinal barrier function, and gut microbiota in a weaned piglet model challenged with lipopolysaccharide (LPS). Methods Thirty-six piglets (Pig Improvement Company line 337 × C48, 28 d of age, 8.87 kg ± 0.11 kg BW) were randomly allocated into 3 treatments and fed with a basal diet (CTL), a diet added 50 mg/kg of aureomycin (AUR), or a diet supplemented with 4000 mg/kg of PCA, respectively. The piglets were challenged with LPS (10 μg/kg BW) on d 14 and d 21 by intraperitoneal injection during the 21-d experiment. Animals (n = 6 from each group) were sacrificed after being anesthetized by sodium pentobarbital at 2 h after the last injection of LPS. The serum was collected for antioxidant indices and inflammatory cytokines analysis, the ileum was harvested for detecting mRNA and protein levels of tight junction proteins by PCR and immunohistochemical staining, and the cecum chyme was collected for intestinal flora analysis using 16S rRNA gene sequencing. Results Dietary supplementation of PCA or AUR significantly increased the expression of tight junction proteins including ZO-1 and claudin-1 in intestinal mucosa, and decreased the serum levels of thiobarbituric acid reactive substances (TBARS) and IL-6, as compared with CTL group. In addition, PCA also decreased the serum levels of IL-2 and TNF-α (P P Prevotella 9, Prevotella 2, Holdemanella, and Ruminococcus torques group (P Roseburia and Desulfovibrio (P Conclusions These results demonstrated that both PCA and AUR had protective effect on oxidative stress, inflammation and intestinal barrier function in piglets challenged with LPS, and PCA potentially exerted the protective function by modulating intestinal flora in a way different from AUR. Holdemanella

Turmeric (Curcuma spp.) are rhizomatous perennial herbs with broad spectrum of pharmacological actions. There are more than 80 species of turmeric and 70 varieties/strains of Curcuma longa, which may have different chemical properties and biological activities. Hence, we compared the major active components (curcuminoides) and antifungal activity of three Curcuma longa strains (Ryudai gold (RD), Okinawa ukon, and BK2), C. xanthorrhiza, C. aromatica, C. amada, and C. zedoaria against Fusarium solani sensu lato (FSSL). The content of curcuminoides was determined by HPLC and the antifungal activity was measured by the diameter of colonies grown on Petri dish, microscopic observation, and CLSI microdilution methods. The BK2 turmeric contained highest concentration of curcumin, demethoxycurcumin, and bisdemethoxycurcumin followed by RD, C. xanthorrhiza, Okinawa ukon, and C. aromatica. These compounds were not detected in C. amada and C. zedoaria. All turmeric species inhibited fungal growth in a concentration-dependent manner. The order of IC50 against FSSL was RD (78 to 92 μg/ml) > BK2 (89 to 101 μg/ml) > C. xanthorrhiza (98 to 114 μg/ml) > C. aromatica (183 to 204 μg/ml) > C. amada (183 to 206 μg/ml) > Okinawa ukon (191 to 216 μg/ml) > C. zedoaria (354 to 385 μg/ml). The results showed a correlation between the antifungal activity and curcuminiods contents of turmeric. Curcumin itself showed marked antifungal activity against FSSL (IC50 = 23 to 25 μg/ml) followed by demethoxycurcumin (IC50 = 25 to 27 μg/ml), while the antifungal activity of bisdemethoxycurcumin was extremely low (IC50 = 216 to 238 μg/ml). However, C. amada and C. zedoaria had no curcuminoids but showed antifungal effects which indicated that other compounds could also inhibit the growth of FSSL. The obtained results demonstrated that turmeric species C. longa (strains Ryudai gold and BK2) and C. xanthorrhiza had higher content of curcuminoids and showed excellent antifungal activity against FSSL.

Chymotrypsinogen is a principal precursor of pancreatic proteolytic enzymes. We previously isolated a cDNA clone for human prechymotrypsinogen from a human pancreatic cDNA library. In the present study, we used this cDNA sequences to isolate genomic DNA clones. Three overlapping cosmid clones spanning approximately 65-kb genomic sequences were isolated from a human cosmid library. The genomic DNA clones were characterized by restriction enzyme mapping and by hybridizing them to subfragments of the cDNA. The sequence tagged sites for human chymotrypsinogen gene were created by designing two oligonucleotides. Furthermore, the isolated genomic clones were confirmed to be localized on chromosome 16q23 by fluorescence in situ hybridization and G-banding analysis.

A chymotrypsinogen showing the phenotype AA of chymotrypsin was purified from quail pancreas, and its chromatographic behavior, molecular weight, and electrophoretic mobility were very similar to those of another chymotrypsinogen, showing the aa phenotype of chymotrypsin. However, after activation, this chymotrypsinogen from AA showed band 5 of chymotrypsin, while the other chymotrypsinogen from aa did not. Peptide mapping demonstrated that the molecular structures of the two chymotrypsinogens are different. It was recognized that chymotrypsin variants result from activated products of different molecular structures of chymotrypsinogens.

A genetic variation was found in pancreatic proteinase of Japanese quail. In eight bands of proteinase isozymes, the variation of band 5 (presence or absence) was detected among quails. Band 5 was identified as a chymotrypsin. The presence and absence of band 5 are controlled by a pair of allelic genes (Prt-5A and Prt-5a) on an autosomal locus, and gene Prt-5A, causing expression of band 5, is dominant to gene Prt-5a, a null allele for band 5. Zymograms of proteinases and their zymogens were also compared; no variation of chymotrypsinogen; corresponding to chymotrypsin Prt 5 were detected. It is suggested that the Prt-5 variant of chymotrypsin may be formed during activation of chymotrypsinogen.