Identification of phenolic compounds in soursop (Annona muricata) pulp by high-performance liquid chromatography with diode array and electrospray ionization mass spectrometric detection

Nutritional and technological potential of umbu-caja and soursop co-product flours

Umbu-caja and soursop from the Northeast region of Brazil are rich in nutrients and bioactive compounds and are widely processed by the fruit agroindustry. However, there is a lack of research examining the composition and nutritional/technological potential of these co-product fruits. The present study evaluated the nutritional and technological characteristics of umbu-caja and soursop co-product flours (UCF and SCF, respectively), in addition to cytotoxicity in healthy cells. The results demonstrated that they are rich in dietary fiber (approximately 53 %), low in protein (approximately 8.0 %), and have minimal moisture content (<15 %). The mineral composition of the flours exhibited a notable presence of copper, iron, zinc, manganese, and boron. The evaluation of antioxidant capacity using the DPPH, ABTS, and FRAP methods demonstrated the presence of antioxidants that resisted processing, indicated by a high antioxidant capacity. Furthermore, the flours were found to contain phenolic compounds, predominantly rutin (UCF) and p-coumaric acid (SCF). The cytotoxicity test demonstrated that both co-product flours did not exert detrimental effects on healthy cells according to the MTT assay. The technological analyses highlighted low pH values (2.38 and 3.61 for UCF and SCF, respectively), which is favorable for a greater shelf life and suggests applications in fermented products. In addition, the flours have good water and oil holding capacity and low foaming, and they could be incorporated into food products that require these properties. The results demonstrated promising qualities of the UCF and SCF for incorporation into the human diet and product development, mainly due to their high fiber content, antioxidant capacity and low cytotoxicity.

Phytochemical and bioactive potentials of African Annonaceae species

This review aims to gather available information on the medicinal, nutritional, and bioactive profiles of Annonaceae species in the African continent, sponsoring their use worldwide and mainly in African communities, where access to food and medicines for basic health care is scarce. >60 medicinal taxa were compiled, belonging to 22 genera, namely Annickia, Annona, Anonidium, Artabotrys, Cleistochlamys, Cleistopholis, Dennettia, Duguetia, Greenwayodendron, Hexalobus, Isolona, Lettowianthus, Monanthotaxis, Monodora, Neostenanthera, Polyceratocarpus, Sphaerocoryne, Uvaria, Uvariastrum, Uvariodendron, Uvariopsis and Xylopia; the most diverse and economically important genera were the genera Annona, Uvaria and Xylopia with 7 species each. Annonaceae species hold a valuable nutritional profile, rich in proteins, fibers, and minerals, being also good sources of a wide range of bioactive compounds of high biological relevance. These compounds are especially important in developing countries, where most of these species are available for direct use as food and/or medicines by the most deprived populations.

Antimutagenic and antitumor activities of a water-soluble fraction of soursop (syn Graviola, Annona muricata L.) fruit pulp

Soursop (Annona muricata) is a tropical tree whose decoction derived from bark, root, seed, or leaf has been used for medicinal uses. In addition, the fruit itself is considered a food, and the juice is utilized to treat heart and liver diseases. The aim of this study was to determine the phenolic content. In addition, a water-soluble fraction of the soursop fruit pulp (WSSP) was examined for the following properties: antioxidant, mutagenic, and antimutagenicity. UV-visible spectrophotometry determined total phenolic content by the Folin-Ciocalteu method to be 11.22 ± 0.6 mg of gallic acid equivalent per gram dried extract, and free-radical scavenging activity by the 2,2'-diphenyl-1-picryl-hydrazyl (DPPH•) showed an EC50 of 1032 µg/ml. In the Salmonella/microsome assay, no marked mutagenicity was induced following WSSP treatment, and a chemopreventive capacity was observed in the antimutagenic assay. The cytotoxicity assays were carried out using the water-soluble tetrazolium salt and lactate dehydrogenase (LDH) assays demonstrated that WSSP induced significant cytotoxicity in MCF-7 and Caco-2 cells, indicating greater effectiveness of cytotoxic action by destroying cell membrane integrity. Data suggest that WSSP may exert beneficial effects as a DNA chemopreventive and antitumor agent.

Metabolomics approach for phenolic compounds profiling of soursop (Annona muricata L.) fruit during postharvest storage

INTRODUCTION

Soursop (Annona muricata L.) is a crop with medicinal properties and numerous bioactive compounds. Ripening is a complex process that regulates fruit quality and changes in metabolite content, such as flavonoids, polyphenols, and organic acids.

OBJECTIVES

This study aimed to analyze the phenolic profiling of soursop fruit ripening.

METHODS

The metabolic changes in different days of storage of soursop fruits were investigated using a semi-metabolomic approach based on ultra-performance liquid chromatography coupled to electrospray ionization quadrupole-time of flight mass spectrometry (UPLC-ESI-QTOF-MS). Further, multivariate analysis such as supervised partial least squares discriminant analysis (PLS-DA) was conducted to identify differential metabolites.

RESULTS

A total of 68 metabolites were identified in soursop fruit during postharvest storage. A higher number of metabolites were identified in the Day zero (D0) compared to the Day one (D1), Day three (D3), and Day five (D5), belonging to flavonoids, other polyphenols, phenolic acids, and organic acids. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the pathways of flavone and flavonol biosynthesis, flavonoid biosynthesis, and biosynthesis of secondary metabolites were mostly enriched. Additionally, we included all the compounds and their postharvest storage in the public Phenolics profile database.

CONCLUSIONS

Here, we show that the stage of ripening has a significant effect on the phenolic content, highlighting the point of cut (D0) and the onset of senescence (D5). The findings of this study provide new insights into the soursop fruit quality and may contribute to the identification of metabolic markers for its storage.

Annona Muricata L. extract restores renal function, oxidative stress, immunohistochemical structure, and gene expression of TNF-α, IL-β1, and CYP2E1 in the kidney of DMBA-intoxicated rats

Introduction: 7,12-dimethylbenz (a) anthracene (DMBA) is a harmful polycyclic aromatic hydrocarbon derivative known for its cytotoxic, carcinogenic, and mutagenic effects in mammals and other species. Annona muricata, L. (Graviola; GRV) is a tropical fruit tree traditionally well-documented for its various medicinal benefits. This investigation is the first report on the potential antioxidant and antinfammatory reno-protective impact of GRV against DMBA-induced nephrotoxicity in rats. Methods: Forty male albino rats were allocated into four equal groups (n = 10). The 1st group served as the control, the 2nd group (GRV) was gastro-gavaged with GRV (200 mg/kg b.wt), the 3rd group (DMBA) was treated with a single dose of DMBA (15 mg/kg body weight), and the 4th group (DMBA + GRV) was gastro-gavaged with a single dose of DMBA, followed by GRV (200 mg/kg b.wt). The GRV administration was continued for 8 weeks. Results and Discussion: Results revealed a significant improvement in renal function, represented by a decrease in urea, creatinine, and uric acid (UA) in the DMBA + GRV group. The antioxidant potential of GRV was confirmed in the DMBA + GRV group by a significant decline in malondialdehyde (MDA) and a significant increase in catalase (CAT), superoxide dismutase (SOD), glutathione S transferase (GST), and reduced glutathione (GSH) compared to DMBA-intoxicated rats; however, it was not identical to the control. Additionally, the antiinflammatory role of GRV was suggested by a significant decline in mRNA expression of cytochrome P450, family 2, subfamily e, polypeptide 1 (CYP2E1), tumor necrosis factor-alpha (TNF-α), and interleukin 1 beta (IL-1β) in the DMBA + GRV group. Moreover, GRV improved the histopathologic and immunohistochemical expression of TNF-α, CYP450, and IL1β in DMBA-intoxicated kidney tissue. Conclusively, GRV is a natural medicinal product that can alleviate the renal injury resulting from environmental exposure to DMBA. The reno-protective effects of GRV may involve its anti-inflammatory and/or antioxidant properties, which are based on the presence of phytochemical compounds such as acetogenins, alkaloids, and flavonoids.

Soursop (Annona muricata) Properties and Perspectives for Integral Valorization

The increased international interest in the properties of soursop (Annona muricata) alerts us to the sustainability of productive chain by-products, which are rich in phytochemicals and other properties justifying their industrial application in addition to reducing the environmental impact and generating income. Chemical characteristics of soursop by-products are widely known in the scientific community; this fruit has several therapeutic effects, especially its leaves, enabling it to be used by the pharmaceutical industry. Damaged and non-standard fruits (due to falling and crushing) (30-50%), seeds (3-8.5%), peels (7-20%), and leaves, although they constitute discarded waste, can be considered as by-products. There are other less cited parts of the plant that also have phytochemical components, such as the columella and the epidermis of the stem and root. Tropical countries are examples of producers where soursop is marketed as fresh fruit or frozen pulp, and the valorization of all parts of the fruit could represent important environmental and economic perspectives. Based on the chemical composition of the fruit as well as its by-products and leaves, this work discusses proposals for the valorization of these materials. Soursop powder, bioactive compounds, oil, biochar, biodiesel, bio-oil, and other products based on published studies are presented in this work, offering new ideas for opportunities for the regions and consumers that produce soursop.

Kinetic Model of Moisture Loss and Polyphenol Degradation during Heat Pump Drying of Soursop Fruit (Annona muricata L.)

The aim of this study is to investigate the impact of time and temperature of the heat pump drying process of soursop slices at different levels on moisture content and total polyphenol content (TPC). Twelve types of classical kinetic models have been used in this work to describe the suitability of experimental data with models. The conformity is assessed based on statistical values (e.g., coefficient of determination (R2), Chi–square value (X2), etc.). The loss of moisture in the material is described in accordance with Fick’s diffusion law. Value of moisture rate (MR), and effective moisture diffusivities (Deff) have been identified. Experimental results show that MR value depends on the time and drying temperature, Deff increases when increasing the drying temperature from 20–50 °C with values of 1.24 × 10−9, 1.85 × 10−8, 7.69 × 10−8, and 5.54 × 10−7 m/s2. The Singh et al. model is the best option to describe the moisture of the sliced soursop drying process at 30 °C (R2 = 0.97815). The largest TPC decomposition occurs at a temperature of 50 °C. The ability to decompose TPC is proportional to the drying temperature. The TPC decomposition dynamic model follows a first–order reaction when drying at 20 °C with a determinant coefficient R2 = 0.9693.

LC-MS Characterization and Quantification of Known and Unknown (Poly)phenol Metabolites-Possible Pitfalls and Their Avoidance

This review focuses on the LC-MS characterization and quantification of dietary (poly)phenols and their metabolites. It draws attention to errors, omissions, and misunderstandings that appear frequently in published papers, and suggests strategies for their avoidance. Aspects covered include the use of authentic standards and surrogate reference materials, the importance of collecting and archiving Total Ion Current MS data, the limitations of using on-line compilations of accurate mass MS data to assign unknown components when multiple isomers are possible, and the often understated magnitude of person-to-person variation that may significantly impact at population level any potential health benefit.

Pharmacological Activities of Soursop (Annona muricata Lin.)

Soursop (Annona muricata Lin.) is a plant belonging to the Annonaceae family that has been widely used globally as a traditional medicine for many diseases. In this review, we discuss the traditional use, chemical content, and pharmacological activities of A.muricata. From 49 research articles that were obtained from 1981 to 2021, A.muricata’s activities were shown to include anticancer (25%), antiulcer (17%), antidiabetic (14%), antiprotozoal (10%), antidiarrhea (8%), antibacterial (8%), antiviral (8%), antihypertensive (6%), and wound healing (4%). Several biological activities and the general mechanisms underlying the effects of A.muricata have been tested both in vitro and in vivo. A.muricata contains chemicals such as acetogenins (annomuricins and annonacin), alkaloids (coreximine and reticuline), flavonoids (quercetin), and vitamins, which are predicted to be responsible for the biological activity of A.muricata.

Current Situation and Perspectives of Fruit Annonaceae in Mexico: Biological and Agronomic Importance and Bioactive Properties

The Annonaceae family is one of the oldest angiosperms. The genus Annona is the one with the most species and, together with Asimina, the only ones that contain edible fruits. In the last 10 years, interest in these fruit species has increased, mainly due to their nutritional properties and their application in the treatment of human diseases. Mexico is the center of origin for most of them. However, at present much of the basic agronomic information, postharvest handling of the fruits, and their potential as new crops for areas with poor soils in organic matter or semi-dry climates is unknown. It is considered that these custard apple species may be an option to change towards instead of crops that have lost profitability and sustainability. A review of the current state of knowledge in different areas of the species A. muricata, A. macroprophyllata, A. reticulata, A. squamosa, and A. cherimola was carried out and to focus research efforts on the topics of greatest interest and on those where is required to achieve a sustainable production and use of these resources in Mexico. However, knowledge about the cultivation and potential uses of these species is needed to increase their commercialization; the integration of interdisciplinary and interinstitutional groups is required.

Screening of antidiabetic and antioxidant potential along with phytochemicals of Annona genus: a review

Background

Annona species can be found in the subtropical and tropical parts of the world. Because of their medicinal capabilities and highly exotic edible fruits, they are one of the most important members of the Annonaceae family. Isoquinolines, pyrimidine-β-carboline alkaloids, lectins, acetogenins, and volatile oils are among the active metabolites found in this genus, all of which have been shown to have anti-diabetic and antioxidant activities.

Main body

The fundamental objective of this review was to summarize the antidiabetic and antioxidant activity based on reported secondary data from different plants of the genus Annona. These species include Annona cherimola, Annona squamosa, Annona macroprophyllata, Annona muricate, Annona reticulata, Annona carcans, Annona coriacea, Annona cornifolia, and Annona senegalensis. The Annona species investigated had significant antihyperglycemic and antioxidant properties.

Conclusion

The available evidence, both in vitro and in vivo, confirms the ability of Annona species to treat diabetes in addition to producing oxidative damage.

Development of comprehensive liquid chromatography with diode array and mass spectrometric detection for the characterization of (poly-)phenolic and flavonoid compounds and application to asparagus

The main objective of the present work was to develop a method for the simultaneous and comprehensive analysis of (poly-)phenolic and flavonoid compounds with liquid chromatography with diode array and mass spectrometric detection and its application to green asparagus samples. To this end, a representative set of polyphenols was used to develop the method. A through method validation was carried out with these. The method was applied to asparagus samples known as a healthy vegetable being rich in bioactive compounds. Polyphenol contents of asparagus samples were determined by carrying out quantitative and qualitative analyses by LC-DAD-ESI/MS. In this context asparagus sample extracts were obtained using solvents of different polarity. The results were evaluated statistically and showed that rutin is the major phenolic compound in asparagus. This demonstrates the versatility of this rapid and sensitive method for the simultaneous analysis of (poly-)phenolic and flavonoid compounds which was successfully applied to asparagus samples.

Phenolic Compounds in Mesoamerican Fruits-Characterization, Health Potential and Processing with Innovative Technologies

Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage.

Phenolic Compounds and Metals in Some Edible Annonaceae Fruits

The concentrations of 3,4-dihydroxybenzoic acid, caffeic acid, catechin, chlorogenic acid, epicatechin, gallic acid, p-coumaric acid, quercetin, rutin, ferulic acid, and the major metals in graviola (Annona muricata), atemoya (A. squamosa x A. cherimola), fruta do conde (A. squamosa), biribá (Rollinia mucosa), and the North American pawpaw (Asimina triloba) were determined by UPLC-ESI (-)-MS/MS. It enabled the identification and quantification of phenolic compounds. Catechin was only found in atemoya, at a concentration of 38.6 μg/g-dw. Only 3,4-dihydroxybenzoic acid was found in the fruit pulps of all five fruits analyzed. Atemoya stands out for not only having catechin but also for having much more epicatechin (239 μg/g-dw) than the other fruits. At the same time, graviola had more p-coumaric acid (62.6 μg/g-dw), and the North American pawpaw had more chlorogenic acid (48.1 μg/g-dw) than the other fruits. Metals were determined by ICP equipped with axially viewed plasma. All five fruit pulps had relatively high levels of potassium, with concentrations ranging from 7640 to 15,000 μg/g-dw, with pawpaw being the lowest and atemoya being the highest. The concentrations of other metals ranged from Ca 547 to 1110, Na 14.3 to 123, P 1210 to 1690, Mg 472 to 980, Mn 1.86 to 5.27, and Zn 5.55 to 7.32 μg/g-dw. All five fruits in the Annonaceae family that were analyzed in this study have several phenolic compounds in them and were good sources of potassium, calcium, phosphorus, and magnesium.

Phytochemical and Antioxidant Dynamics of the Soursop Fruit (Annona muricata L.) in response to Colletotrichum spp

This work evaluates the effect of the pathogens Colletotrichum siamense and C. gloeosporioides on the response of soursop fruits. The bioactive compounds (total phenols, flavonoids, anthraquinones, coumarins, steroids, terpenoids, alkaloids, and saponins) were evaluated qualitatively in soursop pulp. Positive phytochemicals and antioxidant activity (DPPH•, ABTS•+, and FRAP) were quantified at day zero, one, three, and five. Fruits treated with C. gloeosporioides showed higher disease severity (P<0.05). Early fruit response (day one) was observed with both pathogens, increased the concentration of saponins and repressed the production of quercetin 3-O-glucoside (P<0.05). Likewise, C. siamense decreased total soluble phenols and flavonoids and increased antiradical activity DPPH•. Besides, C. gloeosporioides decreased the levels of kaempferol 3-O-rutinoside and ferulic acid (P<0.05). Regarding the late response (day three), both pathogens decreased the concentration of saponins and increased flavonoids and phytosterols (P<0.05). Nevertheless, C. siamense increased the levels of total soluble phenols, p-coumaric acid, kaempferol, and antiradical activity FRAP (P<0.05). Also, C. gloeosporioides repressed the production of quercetin 3-O-glucoside at day five (P<0.05). Soursop fruits had a response to the attack of Colletotrichum during ripening at physicochemical and oxidative levels, which is associated with the production of compounds related to the development inhibition of pathogens. Even so, soursop fruits showed higher susceptibility to C. gloeosporioides and higher sensitivity to the attack of C. siamense.

Effect of moderate thermal treatments on the inactivation of a strain of Listeria monocytogenes and physicochemical properties of soursop pulp

Soursop (Annona muricata L.) is a commercially important tropical fruit, whether fresh or processed as a pasteurized or frozen pulp used to prepare juice, drinks, nectar, ice cream, popsicles, and desserts. Besides preserving quality, another preoccupation in the processing of fruit pulps is product safety. Several studies show the association between pulp processing and the development of various microorganisms; however, few have focused on the association between L. monocytogenes and the pulp of sour fruits. The objective was to evaluate the effect of moderate thermal treatments on the inactivation of L. monocytogenes and the physicochemical properties in soursop pulp in order to determine the best processing conditions that will allow to maintain quality as well as to achieve an adequate level of safety. Thermal inactivation kinetics were obtained for L. monocytogenes inoculated in soursop pulp at five levels of temperature (50, 52.5, 55, 57.5, and 60 ℃) and different exposure times (0-60 min). The survival curves did not suggest a log-linear relationship, and were, consequently, fitted to the modified Gompertz equation. The results indicated that the modified Gompertz equation provided an acceptable goodness of fit. Five-log₁₀ cycles reductions of L. monocytogenes were achieved at 50 ℃/60 min, 52.5 ℃/16 min, 55 ℃/10 min, 57.5 ℃/5 min, and 60 ℃/1.25 min. These 5-log₁₀ treatments applied to the soursop pulp indicated that the soursop pulp showed changes in the color parameters and a decrease in the content of total sugars, reducing sugars, ascorbic acid, total phenols, and pH.

Effect of Annona Muricata L. on Metabolic Parameters in Diabetes Mellitus: A Systematic Review

In recent decades, numerous scientific investigations have been conducted to study the antidiabetic effects of Annona muricata L. However, no comprehensive evidence-based systematic review regarding this topic is available. Hence, this study was conducted to systematically evaluate the studies of the efficacy of A. muricata in diabetes management. Six online databases used to search for the related articles. The search terms used were A. muricata/ soursop in combination with diabetes, glucose, and insulin. Seventeen studies were identified that fit the inclusion criteria (1 clinical, 10 in vivo, 4 in vitro, 1 in vivo/ in vitro and 1 in silico). A clinical study showed the positive adjuvant effect of A. muricata to glibenclamide in type 2 diabetes patients. In vivo studies reported beneficial effects of A. muricata in murine models to include decreasing fasting blood glucose level, attenuating diabetes-associated weight loss, increasing serum insulin, improving the lipid profile, normalizing the activity of antioxidant enzymes, and exerting pancreas-protective and hepatoprotective effects. In vitro studies of A. muricata demonstrated its potential for reducing post-prandial glucose level by inhibiting pancreatic α-amylase, lipase, and α-glucosidase and lowering oxidative stress by inhibiting glycation and lipid peroxidation. Additionally, the in-silico study suggested a positive effect of A. muricata in enhancing insulin sensitivity. A. muricata showed a promising effect on the metabolic parameters in diabetes mellitus. Considering that A. muricata is widely consumed worldwide, further exploration of its therapeutic potential is worthwhile.

Valorization of byproducts from tropical fruits: Extraction methodologies, applications, environmental, and economic assessment: A review (Part 1: General overview of the byproducts, traditional biorefinery practices, and possible applications)

Tropical fruits represent one of the most important crops in the world. The continuously growing global market for the main tropical fruits is currently estimated at 84 million tons, of which approximately half is lost or wasted throughout the whole processing chain. Developing novel processes for the conversion of these byproducts into value-added products could provide a viable way to manage this waste problem, aiming at the same time to create a sustainable economic growth within a bio-economy perspective. Given the ever-increasing concern about sustainability, complete valorization through a bio-refinery approach, that is, zero waste concept, as well as the use of green techniques is therefore of utmost importance. This paper aims to report the status on the valorization of tropical fruit byproducts within a bio-refinery frame, via the application of traditional methodologies, and with specific attention to the extraction of phenolics and carotenoids as bioactive compounds. The different types of byproducts, and their content of bioactives is reviewed, with a special emphasis on the lesser-known tropical fruits. Moreover, the bioactivity of the different types of extracts and their possible application as a resource for different sectors (food, pharmaceutical, and environmental sciences) is discussed. Consequently, this review presents the concepts of tropical fruit biorefineries, and the potential applications of the isolated fractions.

Evaluation of nutritional characteristics and bioactive compounds of soursop-yoghurt and soursop-frozen dessert

The nutritional quality, sensory attributes, polyphenols and acetogenins content in yoghurt and frozen dessert formulated with soursop pulp were investigated. The addition of soursop pulp to yoghurt and frozen dessert improved the sensory attributes and the nutritional quality of soursop dairy products resulting in a composition of 0.92 and 2.17% of dietary fiber, 11.25 and 9.84 mg/100 g of vitamin C as well as 243.02 and 490.98 mg/100 g of total polyphenols, respectively. Acetogenins were extracted from both dairy products using maceration, sonication, microwave and Soxhlet. Sonication showed to be faster and safer than the other methods for acetogenins extraction. Higher annonacin (an acetogenin) content was found in yoghurt (38 ng/g) than in frozen dessert (15 ng/g). The quantification of bioactive compounds implied the nutraceutical properties to yoghurt and ice cream when they are added with soursop pulp. The results are useful for the consumers seeking healthier foods.

Theoretical study of the antioxidant capacity of the flavonoids present in the Annona muricata (Soursop) leaves

A theoretical approach was used to evaluate the antioxidant capacity of 20 flavonoids reported in Annona muricata leaves. The theoretical study was at the GGA level using the wB97XD functional and the cc-pvtz basis set. The calculations were performed in gas phase and implicit solvent phase. The flavonol robinetin (03c) and the flavanol gallocatechin (01c) are species that exhibited the best antioxidant capacity in the HAT, SEPT, and SPLET mechanisms. On the other hand, in the SET I mechanism, flavonol quercetin (03b) was the best, and in the SET II mechanism, the most favored species is the flavanol catechin (01a). However, these species do not achieve to overcome the antioxidant capacity presented by the Trolox.

Compuestos fenólicos y actividad antioxidante de los extractos de la hoja de chirimoya (Annona cherimola Mill)

Después de la cosecha del fruto chirimoya, los árboles liberan enormes cantidades de hojas, las cuales son quemadas por los agricultores. Este trabajo muestra que las hojas pueden ser usadas para nuestro beneficio como antioxidante. Se determinaron los compuestos fenólicos (CF) y la actividad antioxidante (AA) de los extractos de la hoja seca de Annona cherimola Mill en etanol al 70% v/v, agua a 80 °C, y agua subcrítica (AS) a 110, 120 y 130 °C, siguiendo un diseño factorial con el programa Minitab. Los CF se cuantificaron con la metodología de Folin Ciocalteu y la AA con el 2,2-difenil-1-picrilhidrazilo (DPPH) y con el poder antioxidante reductor del hierro (FRAP). Los resultados indicaron que el tipo de solvente y el tiempo de extracción presentaron un efecto significativo en el contenido de CF y AA de los extractos. Se concluyó que el extracto de hoja de chirimoya es un potencial antioxidante. El extracto de AS a 130 °C presentó el mayor contenido de CF (5,6 g EAG/100 g de hoja seca) y el extracto etanólico presentó mayor AA (0,86 mg equivalente trolox/mg extracto seco; IC50=0,020 mg de extracto seco/mL de extracto de hoja seca y FRAP de 1710,14 μmol equivalente trolox /g de hoja seca) y los extractos obtenidos con AS a menor temperatura presentaron mayores valores de AA.

Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Annona muricata By-Products and Pulp

Ultrasound-assisted extraction (UAE) is widely used; however, the efficiency of extraction depends on the raw materials. Therefore, optimization of UAE must be investigated for each type of plant material. By-products from soursop fruit have not been studied as a source of bioactive compounds. In this work, the optimization of UAE conditions (extraction time (5, 10, and 15 min), pulse cycle (0.4, 0.7, and 1 s), and sonication amplitude (40%, 70%, and 100%)) for the extraction of phenolic compounds (soluble, hydrolyzable, condensed tannins, and total polyphenols) from soursop by-products (seed, peel, and columella) and pulp was evaluated using response surface methodology. The optimal conditions for UAE to obtain the highest total polyphenol content from by-products and pulp was dependent on the raw material. Peel resulted in the highest content of total polyphenols (187.32 mg/g dry matter [DM]) followed by columella (164.14 mg/g DM), seed (36.15 mg/g DM), and pulp (33.24 mg/g DM). The yield of polyphenolic content from peel and columella obtained with UAE was higher (32⁻37%) than conventional extraction for 2 h under stirring (14⁻16%). The contents of gallic acid (0.36⁻15.86 µg/g DM), coumaric acid (0.07⁻1.37 µg/g DM), and chlorogenic acid (9.18⁻32.67 µg/g DM) in the different parts of the fruit were higher in the extracts obtained by UAE compared with a conventional extraction method (0.08⁻0.61, 0.05⁻0.08, 3.15⁻13.08 µg/g DM, respectively), although it was dependent on the raw materials. Soursop by-products can be functionally important if they are used to extract bioactive compounds by UAE; a technology with high potential for commercial extraction on a large scale.

Purification and biochemical characterization of polyphenol oxidase from soursop (Annona muricata L.) and its inactivation by microwave and ultrasound treatments

The soursop (Annona muricata L.) is a climacteric fruit that may undergo enzymatic browning during ripening, mainly by the activity of polyphenol oxidase (PPO). Soursop PPO was purified 160-fold by hydrophobic interaction and ion-exchange chromatography. The native structure has a molecular weight of 112 kDa corresponding to a dimeric structure. The protein has an optimum pH and temperature of 6.5 and 25°C, respectively; and activation energy of 40.97 kJ·mol^-1 . The lowest K_m value was observed for caffeic acid (0.47 mM); the best substrate was 4-methyl-catechol (1,067 U·mM^-1  min^-1 ). Inactivation assays showed that PPO was completely inactivated by tropolone, Na₂ S₂ O₅ and ascorbic acid, and thermally at 55°C for <5 min, microwave exposure reduced activity to 57% at 70 W in 30 s and ultrasound treatment diminished activity to 43% at 120 W in 220 s. This study allows a better understanding of soursop PPO behavior and provides inactivation information. PRACTICAL APPLICATIONS: The conservation of fresh fruits is complicated due to the enzymatic reactions that are present in fruits, such as enzymatic browning. The enzymes responsible for these reactions can be inactivated by, different chemical compounds as well as by the use of emerging technologies, such as microwaves and sonication, which seek to satisfy the consumer needs to obtain fresh products with good nutritional characteristics and adequate safety.

Exploring the Leaves of Annona muricata L. as a Source of Potential Anti-inflammatory and Anticancer Agents

The use of anti-inflammatory natural products to treat inflammatory disorders for cancer prevention and therapy is an appealing area of interest in the last decades. Annona muricata L. is one of the many plant extracts that have been explored owing to their anti-inflammatory and anticancer effects. Different parts of A. muricata especially the leaves have been used for various ethnomedicinal purposes by traditional healers to treat several diseases including cancer, inflammation, diabetes, liver diseases, and abscesses. Some of these experience-based claims on the use of the plant have been transformed into evidence-based information by scientific investigations. The leaves of the plant have been extensively investigated for its diverse pharmacological aspects and found eminent for anti-inflammatory and anticancer properties. However, most studies were not on the bioactive isolates which were responsible for the activities but were based on crude extracts of the plant. In this comprehensive review, all significant findings from previous investigations till date on the leaves of A. muricata, specifically on their anti-inflammatory and anticancer activities have been compiled. The toxicology of the plant which has been shown to be due to the presence of neurotoxic annaceous acetogenins and benzyltetrahydro-isoquinoline alkaloids has also been updated to provide recent information on its safety aspects. The present knowledge of the plant has been critically assessed, aimed at providing direction toward improving its prospect as a source of potential anti-inflammatory and anticancer agents. The analysis will provide a new path for ensuring research on this plant to discover new agents to treat inflammatory diseases and cancer. Further in vitro and in vivo studies should be carried out to explore the molecular mechanisms underlying their anti-inflammatory responses in relation to anticancer activity and more detail toxicity study to ensure they are safe for human consumption. Sufficient preclinical data and safety data generated will allow clinical trials to be pursued on this plant and its bioactive compounds.

Annonaceae: Breaking the Wall of Inflammation

Inventories of tropical forests have listed Annonaceae as one of the most diverse plant families. For centuries, it is employed in traditional medicines to cure various pathological conditions including snakebite, analgesic, astringent, diarrhea, dysentery, arthritis pain, rheumatism, neuralgia, and weight loss etc. Phytochemical analysis of Annonaceae family have reported the occurrence of alkaloids, flavonoids, triterpenes, diterpenes and diterpene flavone glycosides, sterols, lignans, and annonaceous acetogenin characteristically affiliated with Annonaceae sp. Numerous past studies have underlined the pleotropic pharmacological activities of the crude extracts and isolated compounds from Annonaceae species. This review is an effort to abridge the ethnobotany, morphology, phytochemistry, toxicity, and particularly focusing on the anti-inflammatory activity of the Annonaceae species.

Cold Storage of Two Selections of Soursop (Annona muricataL.) in Nayarit, Mexico

The maturity of two selections of soursop (G1 and G2) from Nayarit, Mexico, was evaluated under environmental conditions at 22°C and refrigeration at 15°C stored for 6 and 8 days, respectively. Maximum CO2and ethylene values were present on the fifth and sixth day. The fruits exposed at 15°C had a significantly lower weight loss (5%) and showed no chilling injury. The firmness of two selections decreased more than 90%. The concentration of TSS increased to 5.3 to 15°Brix, and the titratable acidity was higher for fruit stored at 22°C. The highest concentration of phenols was recorded on the fourth day of storage at 22°C. The enzymatic activity of PPO was increased from physiological ripening to consumption ripening for both treatments. The two selections stored at 22°C registered the highest level of PME activity at ripeness. Shelf life was increased by up to 8 days (4 days at 15°C plus 4 days at 22°C) without causing chilling injury or alterations in the ripening process of the fruits. No significant differences were observed between the two selections evaluated; postharvest handling was considered to be similar; however, it would be advisable to evaluate other technologies combined with refrigeration.

Label-free potentiometric biosensor based on solid-contact for determination of total phenols in honey and propolis

We developed a label-free potentiometric biosensor using tyrosinase extracted from Musa acuminata and immobilized by covalent bond on a surface of a solid-contact transducer. The transducer was manufactured containing two layers. The first layer contained a blend of poly(vinyl) chloride carboxylated (PVC-COOH), graphite and potassium permanganate. On this layer, we deposited a second layer containing just a mixture of poly(vinyl chloride) carboxylated and graphite. On the last layer of the transducer, we immobilized the tyrosinase enzyme by reaction with N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride. The solid-contact potentiometric biosensor presented at low detection limit of 7.3×10^-7M and a linear range to catechol concentration between 9.3×10^-7M and 8.3×10^-2M. This biosensor was applied to determine the amount of total phenols in different samples of honey and propolis. The results agreed with the Folin-Ciocalteu method.

Distribution of Phenolic Contents, Antidiabetic Potentials, Antihypertensive Properties, and Antioxidative Effects of Soursop (Annona muricata L.) Fruit Parts In Vitro

Soursop fruit has been used in folklore for the management of type-2 diabetes and hypertension with limited information on the scientific backing. This study investigated the effects of aqueous extracts (1 : 100 w/v) of Soursop fruit part (pericarp, pulp, and seed) on key enzymes linked to type-2 diabetes (α-amylase and α-glucosidase) and hypertension [angiotensin-I converting enzyme (ACE)]. Radicals scavenging and Fe(2+) chelation abilities and reducing property as well as phenolic contents of the extracts were also determined. Our data revealed that the extracts inhibited α-amylase and α-glucosidase and ACE activities dose-dependently. The effective concentration of the extract causing 50% antioxidant activity (EC50) revealed that pericarp extract had the highest α-amylase (0.46 mg/mL), α-glucosidase (0.37 mg/mL), and ACE (0.03 mg/mL) inhibitory activities while the seed extract had the least [α-amylase (0.76 mg/mL); α-glucosidase (0.73 mg/mL); and ACE (0.20 mg/mL)]. Furthermore, the extracts scavenged radicals, reduced Fe(3+) to Fe(2+), and chelated Fe(2+). The phenolic contents in the extracts ranged from 85.65 to 560.21 mg/100 g. The enzymes inhibitory and antioxidants potentials of the extracts could be attributed to their phenolic distributions which could be among the scientific basis for their use in the management of diabetes and hypertension. However, the pericarp appeared to be most promising.

Annona muricata (Annonaceae): A Review of Its Traditional Uses, Isolated Acetogenins and Biological Activities

Annona muricata is a member of the Annonaceae family and is a fruit tree with a long history of traditional use. A. muricata, also known as soursop, graviola and guanabana, is an evergreen plant that is mostly distributed in tropical and subtropical regions of the world. The fruits of A. muricata are extensively used to prepare syrups, candies, beverages, ice creams and shakes. A wide array of ethnomedicinal activities is contributed to different parts of A. muricata, and indigenous communities in Africa and South America extensively use this plant in their folk medicine. Numerous investigations have substantiated these activities, including anticancer, anticonvulsant, anti-arthritic, antiparasitic, antimalarial, hepatoprotective and antidiabetic activities. Phytochemical studies reveal that annonaceous acetogenins are the major constituents of A. muricata. More than 100 annonaceous acetogenins have been isolated from leaves, barks, seeds, roots and fruits of A. muricata. In view of the immense studies on A. muricata, this review strives to unite available information regarding its phytochemistry, traditional uses and biological activities.

Antiproliferative activity and induction of apoptosis by Annona muricata (Annonaceae) extract on human cancer cells

Background

Annona muricata (A. muricata) is widely distributed in Asia, Africa and South America. Different parts of this plant are used to treat several diseases in Cameroon. The aim of this study is to determine the in vitro anti-proliferative effects and apoptotic events of A. muricata extracts on HL-60 cells as well as to quantify its phenols content.

Methods

The cell viability was measured by using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay while the changes in morphology of HL-60 cells, membrane mitochondrial potential (MMP) and the cell cycle were used for assessment apoptosis induction.

Results

The results show that the concentration of phenols, flavonoids and flavonols in the extracts varied depending on the part of the plant. All the extracts tested inhibited the proliferation of HL-60 cells in a concentration dependent manner with IC₅₀ varied from 6–49 μg/mL. The growth inhibition of the cells by extracts was associated with the disruption of MMP, reactive oxygen species (ROS) generation and the G0/G1 cell arrest.

Conclusion

These findings suggest that the extracts from A. muricata have strong antiproliferation potential and can induce apoptosis through loss of MMP and G0/G1 phase cell arrest.