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Acteoside and salidroside are major phenylethanoid glycosides (PhGs) in Osmanthus fragrans Lour. flowers with extensive pharmacological activities and poor oral bioavailability. The absorption mechanisms of these two compounds remain unclear. This study aimed to investigate the bioaccessibility of these compounds using an in vitro gastrointestinal digestion model and to examine the absorption and transport mechanisms of PhGs using the Caco-2 cell model. The in vitro digestion model revealed that the bioaccessibility of salidroside (98.7 ± 1.35%) was higher than that of acteoside (50.1 ± 3.04%), and the superior bioaccessibility of salidroside can be attributed to its stability. The absorption percentages of total phenylethanoid glycoside, salidroside, and acteoside were 1.42-1.54%, 2.10-2.68%, and 0.461-0.698% in the Caco-2 model, respectively. Salidroside permeated Caco-2 cell monolayers through passive diffusion. At the concentration of 200 μg/mL, the apparent permeability ( P app ) of salidroside in the basolateral (BL)-to-apical (AP) direction was 23.7 ± 1.33 × 10 -7 cm/s, which was 1.09-fold of that in the AP-to-BL direction (21.7 ± 1.38 × 10 -7 cm/s). Acteoside was poorly absorbed with low P app (AP to BL) (4.75 ± 0.251 × 10 -7 cm/s), and its permeation mechanism was passive diffusion with active efflux mediated by P-glycoprotein (P-gp). This study clarified the bioaccessibility, absorption, and transport mechanisms of PhGs. It also demonstrated that the low bioavailability of acteoside might be attributed to its poor bioaccessibility, low absorption, and P-gp efflux transporter.

Ethnopharmacological Relevance: Osmanthus fragrans var. thunbergii (O. fragrans) flower has been consumed as folk medicine for thousands of years. O. fragrans flower extract is a well-characterized phenylethanoid glycoside-rich extract, which has been used as a natural anti-oxidant. The aim of this study was to evaluate the safety of O. fragrans flower phenylethanoid glycoside-rich extract (OFFE)., Materials and Methods: The OFFE was extracted by 80% (v/v) aqueous ethanol with 0.01% sodium isoascorbate (w/v) from the O. fragrans flower and purified on HPD300 resins. The total phenylethanoid glycosides content and individual phenylethanoid glycosides was determined by photocolorimetric method and reversed phase UPLC respectively. An acute oral toxicity study, reverse mutation test, bone marrow cell micronucleus test, and sperm abnormality test as well as a 90-day oral toxicity study were performed on experimental animals., Results: The total content of phenylethanoid glycosides in OFFE was 73.4g acteoside equivalent per 100g of extract, include acteoside (52.5g per 100g of extract), salidroside (13.8g per 100g of extract), and isoacteoside (2.6g per 100g of extract) and so on. No acute lethal effect at the maximal tested OFFE dose of 10g/kg body weight (bw) in either rats or mice was observed, suggesting that OFFE can be considered nontoxic. No evidence for mutagenicity was detected in any of the three mutagenic tests. Administration at levels of 0.50, 1.00, and 2.00g/kg bw to rats for 90 days failed to induce any significant hematological, clinical, chemical, or histopathological changes. The no-observed adverse-effect-level for OFFE was >2.00g/kg bw for the study on subchronic toxicity., Conclusion: The results showed that consuming OFFE has no adverse effects and poses no health risk in the acute oral toxicity study, subchronic oral toxicity study, and in the micronucleus test, which may provide supportive evidence for the safety of OFFE powder that has been used in medicine as well as in functional foods, and dietary supplements., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Osmanthus fragrans flower extract (OFE) is an organic extract from O. fragrans flower, which exhibits neuroprotective, free radical scavenging, and antioxidant effects. Therefore, the protective effect of OFE and acteoside against aging was studied. An aging ICR mouse model was established by chronically administering d-galactose (250 mg/kg) for 8 weeks. d-galactose induced spatial learning and memory impairments that were successfully inhibited by OFE and acteoside, which could shorten escape latency, improve platform crossing times, and increase zone time. The antioxidant potential of OFE and acteoside in vivo was evaluated by estimating the following: activities of antioxidant enzymes, such as glutathione peroxidase and aging-related enzyme, particularly monoamine oxidase; contents of lipid peroxidation methane dicarboxylic aldehyde, advanced glycation end products, and 8-hydroxy-2'-deoxyguanosine (a DNA damage product); and levels of nuclear factor-erythroid 2-related factor 2. OFE and acteoside also inhibited d-galactose-induced neurological aging by suppressing the increase in glial fibrillary acidic protein and neurotrophin-3. Considering the dose-dependent protective effects of OFE and acteoside, we concluded that OFE, rich in acteoside, was a good source of natural antiaging compounds.

Antioxidant capacities and phytochemicals such as phenolics, flavonoids, triterpenoids, phytosterols of four parts of two sugarcane cultivars have been characterised. The total triterpenoid content (TTC), total phenolic content (TPC), total flavonoid content (TFC) and total sterol content (TSC) were different among parts and cultivars of sugarcane. The node of both cultivars contained the highest TTC (2096.02 and 1779.66 mg ursolic acid/100g DW for green-rind and red-rind sugarcane, respectively). However, the highest TPC, TFC and TSC were found in the rind. Green-rind sugarcane cultivars contained higher TSC than the red-rind sugarcane cultivars in most parts, while opposite trend were found in TPC and TFC. Stigmasterol and β-sitosterol were found as two main phytosterols. Furthermore, TPC and TFC revealed good correlations with DPPH and FRAP. As cultivars and parts could affect phytochemical content, present result may provide a theoretical basis for further exploitation of the health beneficial resources of sugarcane., (Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.)

The free and bound phenolic compounds in 10 common Chinese edible flowers were investigated using reversed phase high-performance liquid chromatography. Their antioxidant capacities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging activity, oxygen radical absorption capacity (ORAC), ferric reducing antioxidant power (FRAP), and cellular antioxidant activity (CAA). Free factions were more prominent in phenolic content and antioxidant capacity than bound fractions. Paeonia suffruticosa and Flos lonicerae showed the highest total phenolic content (TPC) 235.5 mg chlorogenic acid equivalents/g of dry weight and total flavonoid content 89.38 mg rutin equivalents/g of dry weight. The major phenolic compounds identified were gallic acid, chlorogenic acid, and rutin. P. suffruticosa had the highest antioxidant capacity in the DPPH, ABTS, and ORAC assays, which were 1028, 2065, 990 μmol Trolox equivalents/g of dry weight, respectively, whereas Rosa chinensis had the highest FRAP value (2645 μmol Fe(2+) equivalents /g of dry weight). The P. suffruticosa soluble phenolics had the highest CAA, with the median effective dose (EC50 ) 26.7 and 153 μmol quercetin equivalents/100 g of dry weight in the phosphate buffered saline (PBS) and no PBS wash protocol, respectively. TPC was strongly correlated with antioxidant capacity (R = 0.8443 to 0.9978, P < 0.01), which indicated that phenolics were the major contributors to the antioxidant activity of the selected edible flowers., (© 2014 Institute of Food Technologists®)

Cardiovascular protective functions of bamboo shoot angiotensin converting enzyme (ACE) inhibitory peptide (BSP) from bamboo shoot were evaluated, including antihypertensive effect on spontaneously hypertensive rats (SHRs) and antihyperlipidemic effect on high-fat-diet-induced rats. Thirty-day antihypertensive effects of BSP on SHRs were assayed. Asp-Tyr [10 mg/day kg body weight (BW)] and BSP (50 mg/day kg BW) significantly reduced ACE activity in lung at the same level (p < 0.05), while BSP (50 mg/day kg BW) reduced systolic blood pressure (SBP) more effectively for its phenolic compounds, such as ferulic acid and p-coumaric acid, which when combined with ACE inhibitor exert a synergistic effect. BSP could significantly reduce SBP, improve oxidant stress status (GSH-Px, SOD, TAC and MDA), and increase NO level in serum and NOS activity in kidney. BSP decreased total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-c) content and MDA level of hyperlipidemic rats, which might contribute to the ACE inhibitory capacity of Asp-Tyr and the fatty acid synthase inhibitory activity of phenolic compounds.

Unlabelled: The inhibitory effects of oiltea camellia extracts (OCEs) and its active components on fatty acid synthase (FAS) were investigated. OCE potently inhibited the activity of FAS with an half-maximal inhibitory concentration (IC₅₀) value of 2.30 μg/mL. The inhibition kinetic results showed that OCE and acetyl-CoA competitively inhibited FAS but these compounds exhibited mixed inhibition against malonyl-CoA and NADPH. Further study uncovered that the active components of OCE, ellagic acid (EA) and 3-O-methylellagic acid 4'-O-β-D-glucopyranoside (MEAG), which were isolated and purified by high-speed counter-current chromatography (HSCCC) using a 2-phase solvent system of chloroform-ethanol-water-acetic acid (4:3:2:0.01, v/v/v/v), inhibited FAS with IC₅₀ of 2.50 and 37.73 μg/mL, respectively. Their inhibition kinetics were different from that of OCE. Both of them exhibited uncompetitive inhibition for nicotinamide adenine dinucleotide phosphate (NADPH) and decreased the FAS activity through inactivation of acetyl/malonyl transferase on FAS. These results suggest that OCE could be a valuable resource for bioactive substances., Practical Application: With the gradual increase in tea oil production, it was in urgent need of dealing with Camellia fruit hull, which was always discarded because of low economic benefits. Camellia fruit hull has been shown to have significant antioxidant effects including 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability and ferric-reducing antioxidant power. This study found that the ethanolic extract of Camellia fruit hull at low concentration efficiently inhibited FAS activity, which is a potential therapy target of both obesity and cancer. These results suggest that OCE could be a valuable resource for bioactive substances., (© 2011 Institute of Food Technologists®)

Unlabelled: The purpose of this study was to evaluate the mutagenicity and safety of water extract of the fruit hull of Camellia oleifera Abel (WECO), which was prepared using hot-reflux method. The oral maximum tolerated dose (MTD) of WECO was above 20 g/kg body weight both in rats and in mice, which can be regarded as virtually nontoxic. No mutagenicity was found in Ames test, mouse bone marrow cell micronucleus test and mouse sperm abnormality test. In the subacute study, the SD rats were administered orally at 0.5, 1, or 2 g/kg/BW for 30 d. There were no treatment-related toxic effects from WECO. No significant differences were found in parameters of body weight, hematology value, clinical chemistry value, and organ/body weight ratio. The level of no observed adverse effect level (NOAEL) for WECO was 2 g/kg/BW for subacute toxicity study., Practical Application:   With the gradual increase in tea oil production, it was in urgent need of dealing with Camellia fruit hull, which was always discarded because of low economic benefits. Camellia fruit hull has been shown to have significant antioxidant effects including DPPH radical-scavenging ability and ferric-reducing antioxidant power (Zhang and others 2010). Toxicological evaluation of WECO provided a safety assurance of WECO for developing dietary supplements and functional foods.

The ethanolic extract of Prunus mume (EPM) is a novel polyphenol preparation derived from branches (with leaves) of Prunus mume, which could be used as a functional ingredient for antioxidant and antiobesity therapy. The purpose of this study was to evaluate the safety of EPM. An EPM was prepared and evaluated for oral acute and subacute toxicity in Sprague-Dawley rats, while its mutagenic potential was assessed by a reverse mutation test using Salmonella typhimurium, by a bone marrow cell micronucleus test using ICR mice, and by a sperm abnormality test using ICR mice. The results showed no acute lethal effects at the maximal tested EPM dose of 20 g/kg bw in either rats or mice, suggesting that EPM can be regarded as virtually nontoxic. Administration at levels of 0.84, 1.67, and 3.33 g/kg bw to rats for 30 d did not induce any significant hematological, clinical, chemical, or histopathological changes. No mutagenicity evidence was detected in any of the 3 mutagenic tests. The level of "no observed adverse effect" (NOAEL) for EPM was above 3.33 g/kg bw for the subacute toxicity study.

The antioxidant of bamboo leaves (AOB) is a kind of polyphenols-rich extract from bamboo leaves of the Phyllostachys Sieb. et Zucc. family. It has been certificated as a natural antioxidant by the Ministry of Health of the People's Republic of China in 2003, which has a warrant for use in edible oil, meat product, aquatic product and puffed food as a novel food additive. For safely using AOB, it was required to systemic safety evaluation studies. As part of an extensive program of safety evaluation studies, the traditional teratogenicity test and the reproduction study were conducted in Sprague-Dawley rats. In the traditional teratogenicity test, the treatment was well tolerated and no mortality occurred at doses of 0, 1.43, 2.87 and 4.30 g/kg bw per day; weight gain during gestation, food consumption, and food efficiency were similar in all groups; reproductive performance was not effected by the treatment; examination of the fetuses for external, visceral, and skeletal alterations did not reveal any fetotoxic, embryotoxic, or teratogenic effects of AOB. Therefore, a nominal dietary AOB level of 4.30 g/kg bw per day (The value of intended use and potential exposure to human is 860 mg/60 kg bw per day dependent on the period of the study.) was considered to be the no-observed-adverse-effect level following daily oral administration of AOB. The results of our studies indicate safety of AOB and support the use of AOB as a food additive.

Abstract: This study was carried out to evaluate the feasibility of using near infrared (NIR) spectroscopy for determining three antioxidant activity indices of the extract of bamboo leaves (EBL), specifically 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing/antioxidant power (FRAP), and 2,2′-azinobis-(3-ethylbenz-thiazoline-6-sulfonic acid) (ABTS). Four different linear and nonlinear regressions tools (i.e. partial least squares (PLS), multiple linear regression (MLR), back-propagation artificial neural network (BP-ANN), and least squares support vector machine (LS-SVM)) were systemically studied and compared in developing the model. Variable selection was first time considered in applying the NIR spectroscopic technique for the determination of antioxidant activity of food or agricultural products. On the basis of these selected optimum wavelengths, the established MLR calibration models provided the coefficients of correlation with a prediction (r pre) of 0.863, 0.910, and 0.966 for DPPH, FARP, and ABTS determinations, respectively. The overall results of this study revealed the potential for use of NIR spectroscopy as an objective and non-destructive method to inspect the antioxidant activity of EBL. [Copyright &y& Elsevier]