Changes in biochemical compounds in flesh and peel from Prunus persica fruits grown in Tunisia during two maturation stages

Guizhi Fuling Wan ameliorates concanavalin A-induced autoimmune hepatitis in mice

BACKGROUND

Autoimmune hepatitis (AIH) is an immune-mediated hepatic disease associated with intense complications. AIH is more common in females and needs effective drugs to treat. Guizhi Fuling Wan (GZFLW) is a traditional Chinese herbal formula used to treat various gynecologic diseases. In this study, we aim to extend the new use of GZFLW for AIH.

METHODS

The tandem MS-based analysis was used to identify secondary metabolites in GZFLW. Therapeutic effects of GZFLW were tested in a concanavalin A (Con A)-induced AIH model in mice. Ethnopharmacological mechanisms underlying the antiapoptotic, antioxidant, and immunomodulatory protective effects were determined.

RESULTS

Oral administration of GZFLW attenuates AIH in a Con A-induced hepatotoxic model in vivo. The tandem MS-based analysis identified 15 secondary metabolites in GZFLW. The Con A-induced AIH syndromes, including hepatic apoptosis, inflammation, reactive oxygen species accumulation, function failure, and mortality, were significantly alleviated by GZFLW in mice. Mechanistically, GZFLW restrained the caspase-dependent apoptosis, restored the antioxidant system, and decreased pro-inflammatory cytokine production in the livers of Con A-treated mice. Besides, GZFLW repressed the Con A-induced hepatic infiltration of inflammatory cells, splenic T cell activation, and splenomegaly in mice.

CONCLUSIONS

Our findings demonstrate the applicable potential of GZFLW in treating AIH. It prompts further investigation of GZFLW as a treatment option for AIH and possibly other hepatic diseases.

Unsaponifiable Compounds and Phenols Content, Antioxidant and Antitrypsin Activities of Prunus persica Kernel Oil

Although peach kernels are rich in oil, there is a lack of information about its chemical and biological properties. Therefore, the purpose of this study was to determine the lipid profile, antioxidant capacity, and trypsin inhibitory propriety of peach oil extracted from two varieties (sweet cap and O'Henry) cultivated in Tunisia. The investigated peach kernel oil contains significant amount of unsaponifiable (2.1±0.5-2.8±0.2% of oil) and phenolic compounds (45.8±0.92-74.6±1.3 mg GAE/g of oil). Its n-alkane profile was characterized by the predominance of tetracosane n-C24 (47.24%) followed by tricosane n-C23 (34.43%). An important total tocopherol content (1192.83±3.1 mg/kg oil) has been found in sweet cap cultivar. Although rich in polyphenols and tocopherols, the tested oil did not display an inhibitory effect on trypsin. However, all peach oil samples showed effective antioxidant capacity and the highest values (86.34±1.3% and 603.50±2.6 μmol TE/g oil for DPPH test and ORAC assay, respectively) were observed for sweet cap oil. Peach oil has an excellent potential for application in the food and pharmaceutical industries as source of naturally-occurring bioactive substances.

Flavoromics Approach in Critical Aroma Compounds Exploration of Peach: Correlation to Origin Based on OAV Combined with Chemometrics

It is essential to seek the critical aroma compounds to identify the origins of peach as well as provide a guidance for quality evaluation. In this study, the peach was characterized by HS-SPME/GC-MS. Subsequently, the odor activity value (OAV) was calculated to specify the primary aroma-active compounds. Afterwards, the chemometrics methods were employed to explore the potentially critical aroma on the basis of p value, fold change (FC), S-plot, jack-knifing confidence interval, variable importance for projection (VIP), and the Shared and Unique Structures (SUS) plots. As a result, five compounds (methyl acetate, (E)-hex-2-enal, benzaldehyde, [(Z)-hex-3-enyl] acetate, and 5-ethyloxolan-2-one) were considered as critical aromas. Moreover, the multi-classification model was developed with an outstanding performance (accuracy of 100%) using the five critical aroma. Moreover, the potential chemical basis of odors was sought through sensory evaluation. In addition, this study provides the theoretical and practical foundation for geographical origin traceability and quality evaluation.

Pattern Recognition of Varieties of Peach Fruit and Pulp from Their Volatile Components and Metabolic Profile Using HS-SPME-GC/MS Combined with Multivariable Statistical Analysis

A fruit's aroma profile, composed of a complex mixture of volatile organic compounds, is among the core attributes related to the overall taste and consumer preference. Prunus persica L. is a preferred summer fruit with a distinct, favorable olfactory characteristic. The volatile compositions of both peach fruits and fruit pulps from eight peach cultivars (four native and four introduced) was investigated to compare their composition and assess flavor-contributing compounds. In total, 65 compounds were profiled after a HS-SPME-GC-MS analysis: 16 esters, 14 aldehydes, 5 alcohols, 7 hydrocarbons, 7 ketones, 8 acids, and 8 terpenes. The most common compounds were esters, acids, and aldehydes. Although the same compounds were identified in both fruit and pulp, their %TIC (total ion current) differed in favor of the whole fruit. Following the metabolic profiling of the whole fruit and fruit pulp, a total of 44 compounds were identified from the studied varieties. Among them, amino acids, organic acids, sugar alcohols, saccharides, fatty acids, and phenolic acids were identified as existing groups. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative %TIC of the identified volatile compounds fluctuated depending on the studied cultivar. No differences were visible in the PCA biplots, which suggested that the polar and lipid metabolites do not provide significant variations when considering different parts of the fruit, contrary to the volatile compounds. The obtained results could successfully be applied in the metabolic chemotaxonomy of peaches and the differentiation of the metabolites present in different parts of the peach.

Evaluation of Two Water Deficit Models on Phenolic Profiles and Antioxidant Activities of Different Peach Fruits Parts

The present work was designed to evaluate the effects of two water shortage strategies on the phenolic profile and antioxidants activities of four Prunus persica L. cultivars (Flordastar, Early May crest, Rubirich and O'Henry). Over the course of two successive seasons (2016 and 2017), three different irrigation strategies were tested: full irrigation (FI: 100 % crop evapotranspiration (Etc)), sustained deficit irrigation (SDI: 50 % ETc), and cyclic deficit irrigation (CDI: irrigation at 100 % field capacity with a soil moisture of 50 % field capacity). HPLC-UV/VIS profile of phenolic compounds, enzymatic and non-enzymatic antioxidant activities were assessed in exocarp and mesocarp. The results showed that deficit irrigation improved the content of phenolic compounds and the antioxidant activities. In O'Henry, ascorbate peroxidase activity increased significantly under CDI in exocarp (249 %). In conclusion, most cultivars showed an improvement of the fruit quality under SDI, whereas O'Henry fruits gathered the highest phenolic amounts and displayed the best antioxidant activity under CDI.

Chemical characterization and nutritional quality investigations of healthy extra virgin olive oil flavored with chili pepper

The production of extra virgin olive oil (EVOO) flavored with diverse spices, herbs, fruits, and vegetables or natural aromas is believed to provide advantageous properties considering either the high nutritional value or biological activity in addition to the flavoring and industrial aspects. The biological activities including antioxidant and antimicrobial properties of Tunisian EVOO obtained from "Chemlali" variety and mixed with chili pepper were investigated. Molecular analyses, including the detection of twelve olive-infecting viruses and Pseudomonas savastanoi pv savastanoi, were performed to ensure that the samples were obtained from healthy olive trees and EVOO quality was not affected. Quality parameters like free acidity, peroxide number, oxidative stability, and specific absorption at K232 nm and K270 nm were also investigated and no significant variation was revealed. The content of minor compounds such as chlorophylls, carotenoids, and total phenols showed minor changes. However, the profiles of the volatile compounds showed remarkable differences, which appeared to be the main factor for the observed variability in consumer acceptance. The results showed for the first time high quantities of polyphenols and ortho-diphenols. Four colorimetric methods were used for the determination of the antioxidant activity, namely DPPH, ABTS, FRAP, and β-carotene test. Compared to the control, a higher level of antioxidant activity was observed for the flavored EVOO. Furthermore, significant results were obtained in the antimicrobial tests. The quality parameters of the mixture showed no alteration compared to the control. Finally, all the measurements and the chemical characterization gave a scientific basis for food technology innovation of new food products.

Characterization of the major aroma-active compounds in peach (Prunus persica L. Batsch) by gas chromatography-olfactometry, flame photometric detection and molecular sensory science approaches

Aroma profiles and aroma-active compounds of "Yulu" peach from Fenghua (the peach known for the best flavor and quality in China) were investigated by headspace solid-phase microextraction (HS-SPME), solvent-assisted flavor evaporation (SAFE), gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and flame photometric detection (FPD). The combination of these methods improved the analysis and identification of aroma substances compared to the combination of a single aroma extraction method and GC-MS. A total of 85 aroma-active compounds, including 10 sulfur compounds were detected. Methional, methyl 3-(methylthio)propionate, methionol, and benzothiazole were first detected in peaches. These aroma compounds cannot only supplement the database of aroma substances of peaches, but also provide data support for traceability of the origins of "Yulu" peaches. In addition, the odor activity value (OAV) was used to identify the contributions of the most important compounds. The results indicated that hexanal, 3-methylbutanal, (E)-2-hexen-1-ol, 3-mercaptohexyl acetate, (E,E)-2,4-decadienal, 2-methylpropanal, γ-decalactone, 2-methylbutanal, theaspirane, and δ-decalactone were the key aroma-active compounds. The key characteristic aroma components were further ascertained by aroma reconstitution and omission experiments, which showed that the fruity, floral, sulfur, and sour notes could be well simulated. Finally, the perceptual interactions between different sulfur compounds and fruity recombination (FR) were explored. 3-mercaptohexanol and 4-methyl-4-mercaptopentan-2-one could significantly decrease the threshold of FR. The possible reason was that these two sulfur compounds had synergistic effects with the aroma compounds in FR, with the U model confirming the results of these synergistic effects. The perceptual interactions provide a basis for the regulation of characteristic fruity aroma of peach products.

Are Peach Cultivars Used in Conventional Long Food Supply Chains Suitable for the High-Quality Short Markets?

Peaches are climacteric and highly perishable fruits, with a short shelf life, and are prone to rapid deterioration after harvest. In this study, the chemical proprieties, aroma profile and a sensory evaluation were conducted to: (1) characterize and compare fruits of 13 different peach and nectarine cultivars, harvested at physiological maturation; and (2) assess the suitability of these cultivars, that are successfully used in long food supply chains (LFSCs), for their use in short food supply chains (SFSCs). Through statistical analysis clear differences were found among the studied cultivars, and in particular between cultivars suited to SFSCs compared to those suited for LFSCs. Results indicate that, despite all cultivars being planted in the same orchards and with the same pre-harvest management and practices, their post-harvest performances were mainly influenced by the cultivar genetic makeup. Therefore, cultivars conventionally used in SFSCs, such as “Guglielmina” and “Regina di Londa”, had the best aroma, sweetness and juiciness compared to LSCPs ones. In contrast, the LSCPs varieties showed interesting values for firmness and crunchiness.

Stone Fruit as Biofactories of Phytochemicals With Potential Roles in Human Nutrition and Health

Phytochemicals or secondary metabolites present in fruit are key components contributing to sensory attributes like aroma, taste, and color. In addition, these compounds improve human nutrition and health. Stone fruits are an important source of an array of secondary metabolites that may reduce the risk of different diseases. The first part of this review is dedicated to the description of the main secondary organic compounds found in plants which include (a) phenolic compounds, (b) terpenoids/isoprenoids, and (c) nitrogen or sulfur containing compounds, and their principal biosynthetic pathways and their regulation in stone fruit. Then, the type and levels of bioactive compounds in different stone fruits of the Rosaceae family such as peach (Prunus persica), plum (P. domestica, P. salicina and P. cerasifera), sweet cherries (P. avium), almond kernels (P. dulcis, syn. P. amygdalus), and apricot (P. armeniaca) are presented. The last part of this review encompasses pre- and postharvest treatments affecting the phytochemical composition in stone fruit. Appropriate management of these factors during pre- and postharvest handling, along with further characterization of phytochemicals and the regulation of their synthesis in different cultivars, could help to increase the levels of these compounds, leading to the future improvement of stone fruit not only to enhance organoleptic characteristics but also to benefit human health.

The molecular biology of fruity and floral aromas in beer and other alcoholic beverages

Aroma compounds provide attractiveness and variety to alcoholic beverages. We discuss the molecular biology of a major subset of beer aroma volatiles, fruity and floral compounds, originating from raw materials (malt and hops), or formed by yeast during fermentation. We introduce aroma perception, describe the most aroma-active, fruity and floral compounds in fruits and their presence and origin in beer. They are classified into categories based on their functional groups and biosynthesis pathways: (1) higher alcohols and esters, (2) polyfunctional thiols, (3) lactones and furanones, and (4) terpenoids. Yeast and hops are the main sources of fruity and flowery aroma compounds in beer. For yeast, the focus is on higher alcohols and esters, and particularly the complex regulation of the alcohol acetyl transferase ATF1 gene. We discuss the release of polyfunctional thiols and monoterpenoids from cysteine- and glutathione-S-conjugated compounds and glucosides, respectively, the primary biological functions of the yeast enzymes involved, their mode of action and mechanisms of regulation that control aroma compound production. Furthermore, we discuss biochemistry and genetics of terpenoid production and formation of non-volatile precursors in Humulus lupulus (hops). Insight in these pathways provides a toolbox for creating innovative products with a diversity of pleasant aromas.

Bioactivity and chemical characterization of Opuntia macrorhiza Engelm. seed oil: potential food and pharmaceutical applications

In the food industry, there is a continuous search for ingredients that might provide advantageous properties to food products, either considering their nutritional value or bioactivity, as well as flavouring and technological aspects. Crude oils are good examples of this type of ingredient, especially if obtained from nonconventional sources. Accordingly, the Opuntia macrorhiza Engelm. seed oil (OMSO) was chemically characterized and evaluated for different in vitro and in vivo bioactivities. OMSO presented physicochemical characteristics appropriate to be considered as an edible oil, namely low acidity value, stability to oxidation (high peroxide value and low K₂₃₂ and K₂₇₀ values), and high contents of unsaturated fatty acids (as shown by the iodine value) and saponifiable matter. Furthermore, this natural oil, owing to its rich phytochemical profile, showed relevant antioxidant activity (especially in lipid peroxidation inhibition assays), α-glucosidase inhibitory activity, cytotoxicity against human tumour cell lines, antibacterial (mainly against Gram positive species) and antifungal properties, as well as anti-inflammatory and analgesic activities. Furthermore, OMSO did not show any sign of acute toxicity on animals, highlighting its possible use in different applications, considering that this natural product is not expected to induce the adverse effects typically associated with synthetic bioactive agents (e.g., ampicillin, amphotericin B, or lysine acetylsalicilate).

Determination of fruit maturity and its prediction model based on the pericarp index of absorbance difference (IAD) for peaches

Harvest maturity is closely related to peach fruit quality and has a very important effect on the fresh fruit market. Unfortunately, at present, it is difficult to determine the maturity level of peach fruits by artificial methods. The objectives of this study were to develop quadratic polynomial regression models using near-infrared spectroscopy that could determine the peel color difference, fruit firmness, soluble solids content (SSC), soluble sugar, organic acid components, and their relationships with the absorbance of chlorophyll (index of absorbance difference, IAD) in late maturing 'Xiahui 8' peach and 'Xiaguang' nectarine fruits. The analysis was based on data for fruits at veraison, fruits at harvesting maturity, and all fruits. The results showed that firmness has the highest correlation coefficient with IAD. Prediction models for fruit maturity were established between firmness and the IAD of the two cultivars using the quadratic polynomial regression method. Further variance analysis on the one degree term and quadratic term of each equation showed that every partial regression coefficient reached a significant or extremely significant level. No significant difference was observed between estimated and observed values after regression prediction. The regression equations seem to fit well. Other peach and nectarine varieties were used to test the feasibility of maturity prediction by this method, and it was found that maturity was successfully predicted in all the samples. The result indicated that the IAD can be used as an index to predict peach fruit maturity.

Investigation of the aroma of commercial peach (Prunus persica L. Batsch) types by Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and sensory analysis

The aim of this study was to investigate the aroma and sensory profiles of various types of peaches (Prunus persica L. Batsch.). Forty-three commercial cultivars comprising peaches, flat peaches, nectarines, and canning peaches (pavías) were grown over two consecutive harvest years. Fruits were assessed for chemical aroma and sensory profiles. Chemical aroma profile was obtained by proton transfer reaction-mass spectrometry (PTR-MS) and spectral masses were tentatively identified with PTR-Time of Flight-MS (PTR-Tof-MS). Sensory analysis was performed at commercial maturity considering seven aroma/flavor attributes. The four types of peaches showed both distinct chemical aroma and sensory profiles. Flat peaches and canning peaches showed most distinct patterns according to discriminant analysis. The sensory data were related to the volatile compounds by partial least square regression. γ-Hexalactone, γ-octalactone, hotrienol, acetic acid and ethyl acetate correlated positively, and benzeneacetaldehyde, trimethylbenzene and acetaldehyde negatively to the intensities of aroma and ripe fruit sensory scores.

Carotenoids, Phenolic Profile, Mineral Content and Antioxidant Properties in Flesh and Peel of Prunus persica Fruits during Two Maturation Stages

Carotenoids and phenolic profile, antioxidant activity as well as concentrations of selected macronutrients (K, N, Mg, Ca and Na) and micronutrients (Zn, Cu and Mn) in flesh and peel of peach fruit were recorded at two harvest dates. Predominant mineral was potassium, followed by calcium, magnesium and sodium. The concentration of most micronutrients was greater in the peel than in the flesh especially in early season. The concentration of most elements in flesh and peel decreased during fruit maturation. Total carotenoids content varied with respect to the cultivar. β-cryptoxanthin and β-carotene were the major carotenoids in both tissues and flesh contain the lowest amounts. Neochlorogenic acid, chlorogenic acid, catechin, epicatechin, gallic acid, rutin, quercetin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, were detected in both peel and flesh, with chlorogenic acid and catechin being the predominant components. Peel extracts showed markedly higher antioxidant activities, when estimated by ABTS or DPPH assays, than the flesh counterparts, consistent with the observed higher phenolic content. Overall, total phenolics levels increased at full ripening stage in both peel and flesh. The results found herein provide important data on carotenoids, phenolic and macro- and micronutrient changes during fruit growth, and emphases peach fruit as a potential functional food.