Peel of araticum fruit (Annona crassiflora Mart.) as a source of antioxidant compounds with α-amylase, α-glucosidase and glycation inhibitory activities

Flavonoids with lipase inhibitory activity from lemon squeezing waste: isolation, multispectroscopic and in silico studies

BACKGROUND

Obesity is recognized as a lifestyle-related disease and the main risk factor for a series of pathological conditions, including cardiovascular diseases, hypertension and type 2 diabetes. Citrus limon is an important medicinal plant, and its fruits are rich in flavonoids investigated for their potential in managing obesity. In the present work, a green extraction applied to lemon squeezing waste (LSW) was optimized to recover pancreatic lipase (PL) inhibitors.

RESULTS

The microwave-assisted procedure yielded an extract with higher lipase inhibitory activity than those obtained by maceration and ultrasound. The main compounds present in the extract were identified by high-performance liquid chromatographic-mass spectrometric analysis, and hesperidin, eriocitrin and 4'-methyllucenin II were isolated. The three compounds were evaluated for in vitro PL inhibitory activity, and 4'-methyllucenin II resulted in the most promising inhibitor (IC50 = 12.1 μmol L-1; Ki = 62.2 μmol L-1). Multispectroscopic approaches suggested the three flavonoids act as competitive inhibitors and the binding studies indicated a greater interaction between PL and 4'-methyllucenin II. Docking analysis indicated the significant interactions of the three flavonoids with the PL catalytic site.

CONCLUSION

The present work highlights flavonoid glycosides as promising PL inhibitors and proposes LSW as a safe ingredient for the preparation of food supplements for managing obesity. © 2024 Society of Chemical Industry.

Exploring the composition and properties of Centella asiatica metabolites and investigating their impact on BSA glycation, LDL oxidation and α-amylase inhibition

Centella asiatica (L.) Urb. is a small herbaceous plant belonging to the Apiaceae family that is rich in triterpenes, such as asiaticoside and madecassoside. Centella asiatica finds broad application in promoting wound healing, addressing skin disorders, and boosting both memory and cognitive function. Given its extensive therapeutic potential, this study aimed not only to investigate the Centella asiatica ethanolic extract but also to analyze the biological properties of its organic fractions, such as antioxidant antiglycation capacity, which are little explored. We also identified the main bioactive compounds through spectrometry analysis. The ethanolic extract (EE) was obtained through a static maceration for seven days, while organic fractions (HF: hexane fraction; DF: dichloromethane fraction; EAF: ethyl acetate fraction; BF: n-butanol fraction and HMF: hydromethanolic fraction) were obtained via liquid-liquid fractionation. The concentration of phenolic compounds, flavonoids, and tannins in each sample was quantified. Additionally, the antiglycation (BSA/FRU, BSA/MGO, and ARG/MGO models) and antioxidant (FRAP, ORAC, and DPPH) properties, as well as the ability to inhibit LDL oxidation and hepatic tissue peroxidation were evaluated. The inhibition of enzyme activity was also analyzed (α-amylase, α-glycosidase, acetylcholinesterase, and butyrylcholinesterase). We also evaluated the antimicrobial and cytotoxicity against RAW 264.7 macrophages. The main compounds present in the most bioactive fractions were elucidated through ESI FT-ICR MS and HPLC-ESI-MS/MS analysis. In the assessment of antioxidant capacity (FRAP, ORAC, and DPPH), the EAF and BF fractions exhibited notable results, and as they are the phenolic compounds richest fractions, they also inhibited LDL oxidation, protected the hepatic tissue from peroxidation and inhibited α-amylase activity. Regarding glycation models, the EE, EAF, BF, and HMF fractions demonstrated substantial activity in the BSA/FRU model. However, BF was the only fraction that presented non-cytotoxic activity in RAW 264.7 macrophages at all tested concentrations. In conclusion, this study provides valuable insights into the antioxidant, antiglycation, and enzymatic inhibition capacities of the ethanolic extract and organic fractions of Centella asiatica. The findings suggest that further in vivo studies, particularly focusing on the butanol fraction (BF), may be promising routes for future research and potential therapeutic applications.

Antifungal activity of Annona crassiflora Mart. dichloromethane fraction against strains of C. albicans

Products derived from medicinal plants with antimicrobial activity are considered a promising alternative in the treatment of fungal infections. In this perspective, this study proposed to evaluate the antifungal activity of the dichloromethane fraction of Annona crassiflora Mart. against C. albicans strains. Tests were carried out to determine Minimum Inhibitory Concentration (MIC), Minimum Fungicide Concentration (MFC), microbial growth kinetics, fungal cell wall and membrane mechanisms of action, antifungal biofilm activity, and cytotoxic effects on human erythrocytes. The extract presented MIC and MFC values that ranged from 256 µg/mL to 1,024 µg/mL, with fungicidal activity in the microbial growth kinetics assay. The mechanism of action did not occur through damage to the cell wall or via binding to ergosterol in the membrane, though the fraction presents activity against biofilm and is not cytotoxic in human erythrocytes. The dichloromethane fraction of Annona crassiflora Mart. presented antifungal activity and reduced biofilm growth, without toxicity against human erythrocytes; however, further studies are needed to define its mechanism of action.

Araticum (Annona crassiflora Mart.): A critical review for the food industry

This review aimed to critically and comparatively analyze the physicochemical, proximate, nutritional, phytochemical composition, and bioactivities of araticum (Annona crassiflora Mart.) (AAc), a fruit from the Brazilian Cerrado. Additionally, the potential applications of this fruit in the food industry were reviewed. Data and information were collected from the Scopus, Web of Science, and Google Scholar databases. AAc, a fruit mainly studied in the Brazilian regions of Minas Gerais and Goiás, has well-documented physicochemical, proximate, and nutritional characteristics. It is rich in fiber, sugars, vitamins A and C, minerals, and oil, making it attractive to the food industry. However, there are research gaps, such as the impact of climatic conditions on the AAc chemical composition. Additional studies are needed, especially for the peel and seeds, and investigations of pre-treatments effect on the chemical composition are recommended. The application of AAc in food products is mainly limited to pulp, but there is potential for using peels and seeds. AAc is a rich source of phytochemical compounds with various biological properties, such as antioxidants, hepatoprotective, and antimicrobial activities. Future studies should explore other phytochemicals present in the fruit beyond phenolic compounds. The consumption of AAc can contribute to combating food insecurity malnutrition, and promoting the conservation of the Brazilian Cerrado.

Annona crassiflora Mart. Fruit Peel Polyphenols Preserve Cardiac Antioxidant Defense and Reduce Oxidative Damage in Hyperlipidemic Mice

Dyslipidemia and oxidative stress are directly related to the pathogenesis of cardiovascular diseases. Annona crassiflora Mart. (ACM) has been traditionally used in folk medicine to alleviate inflammation and pain. This plant is rich in polyphenols, which exhibit high antioxidant capacity. The present study aimed to elucidate the antioxidant properties of ACM in the heart of hyperlipidemic mice. The animals were orally administered either a crude ethanol extract (CEAc) or a polyphenols-rich fraction (PFAc) obtained from ACM fruit peel. There were correlations between blood and fecal biochemical data with cardiac oxidative stress biomarkers. Here, the pre-treatment with CEAc for 12 d led to an increase in glutathione content (GSH) and a reduction in the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase. Moreover, PFAc was found to enhance the total antioxidant capacity as well as GSH, SOD and CAT activities, which were reduced by Triton WR-1339-induced hyperlipidemia. Moreover, the administration of PFAc before the treatment resulted in a decrease in protein carbonylation and lipid peroxidation levels, as well as a reduction in the activities of glutathione reductase and glucose-6-phosphate dehydrogenase. ACM fruit peel showed improvement in the glutathione system, mainly its polyphenols-rich fraction, indicating a potential cardioprotective antioxidant usage of this plant extract.

Scientific Advances in the Last Decade on the Recovery, Characterization, and Functionality of Bioactive Compounds from the Araticum Fruit (Annona crassiflora Mart.)

Araticum (Annona crassiflora Mart.) is a native and endemic species to Brazilian Cerrado whose fruits have high sensorial, nutritional, bioactive, and economic potential. Its use in local folk medicine, associated with recent scientific findings, has attracted growing interest from different industrial sectors. Therefore, understanding the scientific advances achieved so far and identifying gaps to be filled is essential to direct future studies and transform accumulated knowledge into innovative technologies and products. In this review, we summarize the phytochemical composition, bioactivities, and food products from araticum fruit that have been reported in the scientific literature over the past 10 years. The compiled data showed that araticum fruit parts contain a wide range of bioactive compounds, particularly phenolic compounds, alkaloids, annonaceous acetogenins, carotenoids, phytosterols, and tocols. These phytochemicals contribute to different biological activities verified in araticum fruit extracts/fractions, including antioxidant, anti-inflammatory, anti-Alzheimer, anticancer, antidiabetic, anti-obesity, antidyslipidemic, antinociceptive, hepatoprotective, healing of the cutaneous wound, antibacterial, and insecticide effects. Despite the promising findings, further studies-particularly toxicological (especially, with byproducts), pre-clinical, and clinical trials-must be conducted to confirm these biological effects in humans and assure the safety and well-being of consumers.

Xanthones from the latex and twig extracts of Garcinia nigrolineata Planch. ex T. Anderson (Clusiaceae) and their antidiabetic and cytotoxic activities

A new geranylated xanthone, nigrolineaxanthone AA (1) together with 18 known compounds (2-19) were isolated from latex and twig extracts of Garcinia nigrolineata Planch. ex T. Anderson. Some of the isolated compounds were assessed for their antidiabetic activities and cytotoxicity against three cancer cell lines. Of these, compounds 12 (IC₅₀ value of 25.8 ± 0.2 µM), 16 (IC₅₀ value of 124.8 ± 0.7 µM), and 17 (IC₅₀ value of 44.4 ± 1.1 µM) exhibited the highest α-glucosidase inhibitory, α-amylase inhibitory, and glycation inhibition activities, respectively. Compound 11 showed glucose consumption and glucose uptake with IC₅₀ values of 14.2 ± 0.8 µM and 3.1-fold. Compound 10 displayed cytotoxic activity against colon cancer (SW480) with an IC₅₀ value of 4.3 ± 0.1 µM), while compound 2 showed cytotoxicity against leukemic cancer (K562) with IC₅₀ value of 4.4 ± 0.3 µM.

An Integrative Approach to the Flavonoid Profile in Some Plants' Parts of the Annona Genus

The Annonaceae family is widely distributed in subtropical and tropical regions. Several species of this family are known for their pharmacological and beneficial properties to human health, mainly attributed to flavonoids. The objective of this work was to carry out an integrative review in order to identify the main flavonoids found in some plant parts belonging to the Annona genus: araticum tree (Annona crassiflora Mart.), graviola tree (Annona muricata), atemoya tree (Annona cherimolia Mill × Annona squamosa L.), pinha tree (Annona squamosa), bananinha tree (Annona leptopetala), and marolinho tree (Annona coriacea). Only articles published between the years 2016 to 2021 that answered the guiding question were considered, in order to obtain recent data. Then, search strategies were designated for each database used: Science Direct, CAPES Periodicals, and Scielo. Most of the studies retrieved from the databases are related to fruits. The results showed that the number of flavonoids identified varies according to the analytical methodology used to identify and quantify the compounds. Quercetin was the most commonly found compound in all fruits of the Annona genus studied, and epicatechin, rutin, and kaempferol were also found to a lesser extent. The presence of these compounds in Annona makes the fruit promising, with potential applicability in the pharmaceutical and food industry.

Phytochemical Analysis of the Fruit Pulp Extracts from Annona crassiflora Mart. and Evaluation of Their Antioxidant and Antiproliferative Activities

Annona crassiflora Mart., the marolo fruit of the Cerrado biome, is one of the most frequently consumed species from the Brazilian Midwest. This study aimed to evaluate the chemical composition and the antioxidant and cytotoxic properties of the fruit pulp of A. crassiflora collected at Chapada das Mesas, Maranhão, Brazil. The volatile concentrate was identified as mainly ethyl octanoate, ethyl hexanoate, and methyl octanoate. From the ethanol (LFP-E) and ethyl acetate (LFP-A) extracts were identified phenolic acids (p-coumaric, gallic, quinic, and ferulic), flavones and derivatives (apigenin, epicatechin, 2′-5-dimethoxyflavone, 3′,7-dimethoxy-3-hydroxyflavone, kaempferol-3-O-glucoside and 3-O-rutinoside, quercetin-3-O-glucoside, procyanidin B2, and rutin), aporphine alkaloids (xylopine, stephagine, and romucosine), and acetogenin (annonacin). For the LFP-E and LFP-A extracts, the total phenolic compound values were 15.89 and 33.16 mg GAE/g, the flavonoid compound content values were 2.53 and 70.55 mg QE/g, the DPPH radical scavenging activity showed EC₅₀ values of 182.54 and 57.80 µg/mL, and the ABTS radical activity showed TEAC values of 94.66 and 192.61 µM TE/g. The LFP-E extract showed significant cytotoxicity and cell selectivity for the U251-glioma strain, presenting a GI₅₀ value of 21.34 µg/mL, which is close to doxorubicin (11.68 µg/mL), the standard chemotherapeutic drug. The marolo fruit seems to be a promising source for developing innovative and healthy products for the food industry.

Polyphenols-Rich Fraction from Annona muricata Linn. Leaves Attenuates Oxidative and Inflammatory Responses in Neutrophils, Macrophages, and Experimental Lung Injury

Annona muricata Linn. is a common plant found in the warmest regions of South and Central America and its use in traditional medicine has been reported for the treatment of various illnesses. In the current study, we investigate the antioxidant and anti-inflammatory activities of crude extract and fractions from A. muricata L. leaves in isolated murine phagocytic immune cells as well as experimental LPS-induced acute lung injury (ALI). In a luminol-dependent chemiluminescence assay, we showed that ethyl acetate (EtOAc.f) and n-butanol (BuOH.f) fractions—both rich in polyphenols—reduced the generation of reactive oxygen species (ROS) by neutrophils stimulated with opsonized zymosan; similar results were found in culture of bone marrow-derived macrophages (BMDMs). By evaluating anti-inflammatory activity in BMDMs, EtOAc.f and BuOH.f reduced secretion of IL-6 and expression of the co-stimulatory molecule CD40. Furthermore, in LPS-induced ALI, oral administration of EtOAc.f reduced myeloperoxidase (MPO) activity in lung tissue. In addition, on a mechanism dependent on glutathione levels, the oxidative damage was also attenuated. These findings revealed direct antioxidant and anti-inflammatory activities of polyphenols-rich fractions of A. muricata L. leaves on neutrophils and macrophages. Moreover, the reduced oxidative damage and levels of inflammatory markers in experimental ALI suggest that these fractions might be explored for the development of new therapies for inflammatory conditions.

Topic use of Annona crassiflora Mart. contributes to wound healing due to the antioxidant and proliferative effects of fibroblasts

Annona crassiflora Mart. is a species native to the Cerrado biome, whose fruit is known as araticum or marolo. Plant parts are widely used in folk medicine to treat inflammation and pain associated with rheumatism, wounds, venereal diseases, snakebites, and microbial infections. Thus, we investigated a fraction rich in phenolic compounds (PCAc) obtained from the crude extract of the peel of these fruits on non-cytotoxic, anti-inflammatory, antioxidant, and collagen biosynthesis properties in the healing of wounds induced on the back of BALB/c mice. For the control group, the induced wounds were not treated and for the others, wounds were treated topically with vehicle or vehicle plus PCAc. Both fractions contained in PCAc demonstrated effective protection on fibroblasts. We highlight the effect of the ethyl acetate fraction which, in addition to the protective effect, has a proliferative activity on these cells. In addition, PCAc caused improvement in healing after 7 days of treatment and in the longest period of treatment with PCAc (7, 14, and 21 days) there was a greater contraction of the wound, accompanied by resolution of the inflammatory process, antioxidant defense, increasing collagen synthesis, and modulation of metalloproteinases. PCAc demonstrated better re-epithelialization and organization of the dermis at the end of treatment. The changes promoted by the phenolic compounds of A. crassiflora were important in the healing process, especially in activities related to inflammation, oxidative stress, and fibrogenesis.

Antioxidant compounds of Kielmeyera coriacea Mart. with α-amylase, lipase and advanced glycation end-product inhibitory activities

Chronic hyperglycemia and hyperlipidemia are associated with excessive formation of reactive oxygen species and advanced glycation end-products. The present study aimed to evaluate the potential in vitro antidiabetic properties of Kielmeyera coriacea inner bark. The main phytochemical compounds were identified by UHPLC-ESI/MSⁿ and the ethanol extract and its fractions were used to evaluate their antioxidant and anti-glycation capacities, as well as their inhibitory potential against glycoside and lipid hydrolases activities. The polar fractions, especially the n-butanol fraction, had free radical scavenging and quenching properties (ORAC and FRAP values>1800 and 1000 µmol trolox eq/g, respectively, and DPPH IC₅₀<4 µg/mL), and inhibited ROS production (p < 0.01), lipid peroxidation (p < 0.001), glycation (IC₅₀ ~ 10 µg/mL in the BSA-fructose assay; IC₅₀ ~ 200 µg/mL in the BSA-methylglyoxal and arginine-methylglyoxal assays), α-amylase (IC₅₀<0.1 µg/mL) and lipase (IC₅₀<5 µg/mL), with no cytotoxicity. Biomolecules well-known as potent antioxidants were identified for the first time in the inner bark of K. coriacea, such as protocatechuic acid, epicatechin and procyanidins A, B and C. Together, our results support the antioxidant, anti-glycation and glycoside and lipid hydrolases inhibitory properties of the inner bark of K. coriacea, a species found in the Brazilian savanna, which makes it especially useful to combat oxidative stress and hyperglycemia and hyperlipidemia.

Antioxidant compounds from Annona crassiflora fruit peel reduce lipid levels and oxidative damage and maintain the glutathione defense in hepatic tissue of Triton WR-1339-induced hyperlipidemic mice

Dyslipidemia is a risk factor for the pathogenesis of several diseases, such as obesity, hypertension, atherosclerosis and cardiovascular diseases. In addition to interfering with serum concentrations of cholesterol and triglycerides, hyperlipidemia is involved in oxidative stress increase and reduction of the endogenous antioxidant defenses. The fruit peel of Annona crassiflora crude extract (CEAc) and its polyphenols-rich fraction (PFAc) were investigated against hypertriglyceridemia, hypercholesterolemia and hepatic oxidative stress in Triton WR-1339-induced hyperlipidemic mice. Lipid parameters in serum, feces and liver, as well as hepatic oxidative status, and enzymatic and non-enzymatic antioxidant defense systems were analyzed. Pre-treatment with CEAc for 12 days decreased hepatic triglycerides and total cholesterol, and similar to PFAc, increased the high-density lipoprotein level. There were reductions in lipid peroxidation and protein carbonylation, as well as restoration of the glutathione defense system and total thiol content in the liver of the hyperlipidemic mice treated with PFAc. The fruit peel of A. crassiflora, a promising natural source of bioactive molecules, showed a potential lipid-lowering action and hepatoprotective activities triggered by reduction of oxidative damage and maintenance of the enzymatic and non-enzymatic antioxidant systems impaired by the hyperlipidemic state.

Stinging Nettles as Potential Food Additive: Effect of Drying Processes on Quality Characteristics of Leaf Powders

Stinging nettle (Urtica dioica L.) is a ubiquitous, multi-utility, and under-utilized crop with potential health benefits owing to its nutritional and bioactive components. The objective of the work is to produce powders by drying wild stinging nettle leaves as a storable, low-cost functional additive to be used in bakery and ready-to-cook products. Convective drying (CD) and freeze-drying (FD) were applied on unblanched (U) or blanched (B) leaves, which were then milled to nettle powders (NPs). The obtained NPs were evaluated for selected physicochemical (moisture, color), techno-functional (flow indices, hygroscopicity), and phytochemical (pigments, phenols) characteristics as well as mineral contents. Blanching improved mass transfer and reduced the oxidative degradation of pigments during drying, but it caused a loss of total phenols content, antioxidant activity, and potassium content. As for the drying method, CD resulted in better flow properties (i.e., Carr Index and Hausner Ratio), while FD retained better the color, pigments, magnesium content, phenolic, and antioxidant parameters. Overall, the evaluated processing methods resulted in different technological properties that can allow for better evaluation of NPs as a food additive or ingredient. Among the NPs, blanched and freeze-dried powders despite showing inferior technological properties can be recommended as more suitable ingredients targeted f or food enrichment owing to better retention of bio-active components.

LC-ESI-QTOF-MS/MS Profiling and Antioxidant Activity of Phenolics from Custard Apple Fruit and By-Products

Custard apple is an edible fruit grown in tropical and subtropical regions. Due to its abundant nutrient content and perceived health benefits, it is a popular food for consumption and is utilized as a medicinal aid. Although some published research had provided the phenolic compound of custard apple, the comprehensive phenolic profiling of Australian grown custard apple is limited. Hence, this research aimed to evaluate the phenolic content and antioxidant potential by various phenolic content and antioxidant assays, followed by characterization and quantification of the phenolic profile using LC-ESI-QTOF-MS/MS and HPLC-PDA. African Pride peel had the highest value in TPC (61.69 ± 1.48 mg GAE/g), TFC (0.42 ± 0.01 mg QE/g) and TTC (43.25 ± 6.70 mg CE/g), followed by Pink’s Mammoth peel (19.37 ± 1.48 mg GAE/g for TPC, 0.27 ± 0.03 mg QE/g for TFC and 10.25 ± 1.13 mg CE/g for TTC). African Pride peel also exhibited the highest antioxidant potential for TAC (43.41 ± 1.66 mg AAE/g), FRAP (3.60 ± 0.14 mg AAE/g) and ABTS (127.67 ± 4.60 mg AAE/g), whereas Pink’s Mammoth peel had the highest DPPH (16.09 ± 0.34 mg AAE/g), RPA (5.32 ± 0.14 mg AAE/g), •OH-RSA (1.23 ± 0.25 mg AAE/g) and FICA (3.17 ± 0.18 mg EDTA/g). LC-ESI-QTOF-MS/MS experiment successfully characterized 85 phenolic compounds in total, encompassing phenolic acids (20), flavonoids (42), stilbenes (4), lignans (6) and other polyphenols (13) in all three parts (pulp, peel and seeds) of custard apple. The phenolic compounds in different portions of custard apples were quantified by HPLC-PDA, and it was shown that African Pride peel had higher concentrations of the most abundant phenolics. This is the first study to provide the comprehensive phenolic profile of Australian grown custard apples, and the results highlight that each part of custard apple can be a rich source of phenolics for the utilization of custard apple fruit and waste in the food, animal feeding and nutraceutical industries.

Antidiabetic and antimicrobial flavonoids from the twigs and roots of Erythrina subumbrans (Hassk.) Merr

The phytochemical investigation of the twig and root extracts of Erythrina subumbrans (Hassk.) Merr. (Fabaceae) resulted in the isolation and identification of a new pterocarpan, erythrinocarpan (1), along with 27 known compounds (2-28). All isolated compounds were evaluated for their antidiabetic, antimicrobial, and anti-inflammatory properties. Compounds 3, 8, 9, and 22 had α-glucosidase inhibitory activity with IC50 values of 13.4 ± 0.05, 24.5 ± 0.13, 29.0 ± 0.05, and 12.8 ± 0.14 μM, respectively, while compound 2 inhibited α-amylase activity with an IC50 value of 67.6 ± 1.12 μM. Compounds 22 and 24 inhibited glycation activity with the IC50 values of 36.9 ± 0.62 and 40.5 ± 0.37 μM, respectively. From cell-based assays, compound 27 showed the highest ability to induce glucose consumption (IC50 29.1 ± 0.86 μM) and glucose uptake (2.8-fold), and to inhibit nitric oxide (NO) production (IC50 52.5 ± 0.56 μM) without cell toxicity. Furthermore, compound 9 showed antimicrobial activities against Gram-positive bacteria and fungi with MIC values ranging from 2-4 μg/mL.

Antidiabetic Activity of Aloe vera Leaves

This research evaluated the potential of using the methanol extract of Aloe vera (L.) Burm.f (AVM) to prevent the formation of AGEs by means of the BSA/glucose assay, BSA-methylglyoxal assay, arginine-methylglyoxal assay, fructosamine, Nɛ-(carboxymethyl) lysine (CML), thiol groups, and carbonyl protein in vitro. The effect of AVM was also evaluated with regard to inhibiting the enzymes α-amylase, α-glucosidase, and pancreatic lipase. For this, the plant was dried, ground, and subsequently macerated with methanol. Aloe vera methanol extract (AVM) significantly decreased the formation of AGEs, as well as the formation of fructosamine, CML, and carbonyl protein. The concentration of 5 mg/ml of AVM presented the best results. AVM significantly inhibited the α-amylase and α-glucosidase enzymes. As regards the content of thiol groups, a significant increase was observed during the four weeks of the experiment. So, we can conclude that Aloe vera methanol extract decreases the formation of AGEs and may inhibit the increase in postprandial glucose, suggesting that AVM can prevent diabetes complications associated with AGE.

Usage of supercritical fluid techniques to obtain bioactive alkaloid-rich extracts from cherimoya peel and leaves: extract profiles and their correlation with antioxidant properties and acetylcholinesterase and α-glucosidase inhibitory activities

The agroindustrial sector is highly concerned with regards to reducing the environmental impact of waste from pruning activities (leaves, branches and bark) and from food industry processes (peels and seeds). In this sense, the wastes generated by cherimoya cultivation and processing industries should be contemplated as a valuable source of biologically active compounds. In this work, we have studied the bioactivity of alkaloid-rich Annona cherimola Mill. extracts obtain by means of supercritical fluid extraction techniques. The extracts were obtained from the peel and leaves using the following optimal conditions: 100 bar of pressure, 75 °C and 15% methanol as co-solvent. High antioxidant capacity (5304.23 ± 73.60 to 21 705.20 ± 1069.31 μmol Trolox equivalent per 100 g), and acetylcholinesterase (IC₅₀ = 87.69 ± 3.42 to 515.02 ± 29.25 μg mL^-1) and α-glucosidase (IC₅₀ = 1097.76 ± 121.12 to 3206.88 ± 97.06 μg mL^-1) inhibitory activities were exhibited by both peel and leaf extracts. Larger alkaloid contents were determined by UHPLC-ESI-MS analysis, with peel extracts presenting a high concentration of N-trans-feruloyl phenethylamine, while leaf extracts were rich in anonine. This work reports novel data on bioactivity of cherimoya peel and leaves and their potential as a source of bioactive compounds.

A New Italian Purple Corn Variety (Moradyn) Byproduct Extract: Antiglycative and Hypoglycemic In Vitro Activities and Preliminary Bioaccessibility Studies

The reuse of byproducts from agricultural and food industries represents the key factor in a circular economy, whose interest has grown in the last two decades. Thus, the extraction of bioactives from agro-industrial byproducts is a potential source of valuable molecules. The aim of this work was to investigate the in vitro capacity of byproducts from a new Italian corn variety, named Moradyn, to inhibit the accumulation of advanced glycation end products (AGEs) involved in several chronic age-related disorders. In addition, the hypoglycemic effect of Moradyn was tested by in vitro enzymatic systems. A Moradyn phytocomplex and its purified anthocyanin fraction were able to inhibit fructosamine formation and exhibited antiglycative properties when tested using BSA-sugars and BSA-methylglyoxal assays. These properties could be attributed to the polyphenols, mainly anthocyanins and flavonols, detected by RP-HPLC-DAD-ESI-MSⁿ. Finally, a Moradyn phytocomplex was submitted to a simulated in vitro digestion process to study its bioaccessibility. Moradyn could be considered as a promising food ingredient in the context of typical type 2 diabetes risk factors and the study will continue in the optimization of the ideal formulation to preserve its bioactivities from digestion.

Antioxidant, antiproliferative and healing properties of araticum (Annona crassiflora Mart.) peel and seed

Araticum (Annona crassiflora Mart.) is a native fruit from Brazilian Cerrado widely used by folk medicine. Nevertheless, the biological effects of its seeds and peel have not been extensively evaluated. We evaluate herein the antioxidant, antiproliferative and healing potential of araticum peel and seeds extracts. HPLC-ESI-MS/MS analysis showed flavonoids, namely epicatechin and quercetin, as the main compounds in peel and seeds extracts, respectively. These extracts showed high content of phenolic compounds (7254.46 and 97.74 µg/g extract) and, as consequence, high antioxidant capacity. Interesting, the seeds extract was more effective than peel extract against all tested cancer cells, especially on NCI-ADR/RES (multidrug resistant ovary adenocarcinoma) cell line. In the cell migration assay by using HaCaT (keratinocyte), the seeds extract induced migration, while the peel extract showed an inhibitory effect. In this way, phenolic content could be related to antioxidant capacity, but it was not related to antiproliferative and healing effect. The araticum seeds extract showed an interesting response to in vitro biological assay although of its low content of phenolic compounds. Unidentified compounds, such as alkaloids and annonaceous acetogenins could be related to it. Araticum has potential to be used as therapeutic plant especially as antiproliferative and healing drug.

Stephalagine, an aporphine alkaloid from Annona crassiflora fruit peel, induces antinociceptive effects by TRPA1 and TRPV1 channels modulation in mice

Pain relief represents a critical unresolved medical need. Consequently, the search for new analgesic agents is intensively studied. Annona crassiflora, a native species of the Brazilian Savanna, represents a potential source for painful treatment. This study aimed to investigate the antinociceptive potential of A. crassiflora fruit peel, focusing on its major alkaloid, stephalagine, in animal models of pain evoked by the activation of transient receptor potential ankyrin 1 (TRPA1) and vanilloid 1 (TRPV1) channels. Male C57BL/6/J mice were submitted to formalin-, cinnamaldehyde-, and capsaicin-induced nociception tests to assess nociceptive behavior, and to the open-field and rotarod tests for motor performance analyses. Moreover, the stephalagine's effect was tested on capsaicin- and cinnamaldehyde-induced Ca²⁺ influx in spinal cord synaptosomes. In silico assessments of the absorption, distribution, metabolism and central nervous system permeability of stephalagine were carried out. The ethanol extract and alkaloidal fraction reduced the nociception induced by formalin. When administered by oral route (1 mg/kg), stephalagine reduced the spontaneous nociception and paw edema induced by TRPV1 agonist, capsaicin, and by TRPA1 agonists, cinnamaldehyde- and formalin, without altering the animals' locomotor activity. The prediction of in silico pharmacokinetic properties of stephalagine suggests its capacity to cross the blood-brain barrier. Furthermore, this alkaloid reduces the capsaicin- and cinnamaldehyde-mediated Ca²⁺ influx, indicating a possible modulation of TRPV1 and TRPA1 channels, respectively. Together, our results support the antinociceptive and anti-edematogenic effects of the A. crassiflora fruit peel and suggest that these effects are triggered, at least in part, by TRPV1 and TRPA1 modulation by stephalagine.

B procyanidins of Annona crassiflora fruit peel inhibited glycation, lipid peroxidation and protein-bound carbonyls, with protective effects on glycated catalase

Advanced glycation end-products (AGEs) have been reported as results of increased oxidative stress. Consequently, the search for new antioxidant and anti-glycating agents is under intense investigation. Plant-derived procyanidins have previously demonstrated anti-glycation properties. Thus, this study aimed to isolate procyanidins from Annona crassiflora fruit peel, a species from the Brazilian Savanna, and investigate their antioxidant and anti-glycation effects. Free radical scavenging and quenching properties, formation of reactive oxygen species (ROS), AGEs, protein carbonyl and thiol groups, lipid peroxidation, crosslinked AGEs, as well as glycated catalase activity, were analyzed. In addition, in silico assessment of absorption, distribution, metabolism, excretion and toxicity was carried out. The procyanidins-enriched fraction, named here as F7, showed high antioxidant and anti-glycation capacities, with inhibitory activities against lipid peroxidation, and AGEs and ROS formation. In addition, there were reductions in AGEs-induced crosslinks and protein carbonyls and protective effects against oxidation of thiol groups and glycated-catalase. ADMET predictions of F7 showed favorable absorption and distribution, with no hepatotoxicity or mutagenicity. Together, our results support the anti-glycation activities of the procyanidins-enriched fraction from A. crassiflora, and suggest that these effects are triggered, at least in part, by scavenging free radical and dicarbonyls intermediates.

Protective effects of a polyphenol-enriched fraction of the fruit peel of Annona crassiflora Mart. on acute and persistent inflammatory pain

Different parts of Annona crassiflora Mart., a native species from Brazilian savanna, were traditionally used for the treatment of a wide variety of ailments including arthritis. Thus, this study aimed to investigate the possible antinociceptive and anti-inflammatory properties of a polyphenol-enriched fraction of the fruit peel of A. crassiflora, named here as EtOAc, in mice. Pro-inflammatory cytokines and nitric oxide (NO) production were evaluated in LPS-activated macrophages. Then, EtOAc fraction was administered by oral route in male C57BL/6/J mice, and the animals were submitted to glutamate-induced nociception and complete Freund's adjuvant (CFA)-induced monoarthritis tests to assess nociception (mechanical, spontaneous and cold pain) and inflammation (edema and neutrophil infiltration), and to the open-field and rotarod tests for motor performance analysis. EtOAc fraction inhibited the production of IL-6 and NO in the LPS-induced macrophages, and reduced spontaneous nociception induced by glutamate, without altering the animals' locomotor activity. In addition, the polyphenol-enriched fraction was able to revert the early and late hyperalgesia induced by CFA, as well as edema at the acute phase. Reduction of myeloperoxidase activity and inflammatory cell infiltration was observed in the paw tissue of mice injected with CFA and treated with EtOAc fraction. Together, our results support the antinociceptive and anti-inflammatory effects of the polyphenol-enriched fraction of A. crassiflora fruit peel and suggest that these effects are triggered, at least in part, by suppressing pro-inflammatory cytokines and neutrophils infiltration.

Araticum (Annona crassiflora Mart.) as a source of nutrients and bioactive compounds for food and non-food purposes: A comprehensive review

Araticum (Annona crassiflora Mart.) is a fruitful tree native to the Brazilian Cerrado biome that holds high nutritional, functional and economic potential. This plant has been used since ancient times by folk medicine for the treatment of several pathological conditions. There has been increasing interest in the development of pulp-based food products as well as the by-products utilization to obtain value-added ingredients. Understanding the chemical composition and biological activities of different botanical parts of Annona crassiflora Mart. provides a basis to support future researches and applications. In this context, this paper carries out an exhaustive review of the scientific literature, on the main phytochemicals of different botanical parts of Annona crassiflora Mart. (fruit, leaves, stem and root) and their biological activities, assessing their potential uses for several industrial segments. Annona crassiflora Mart. fruits and especially their by-products (peel and seeds) and leaves have been shown a wide range of bioactive compounds such as phenolic compounds, alkaloids, annonaceous acetogenins, tocols, carotenoids, phytosterols, dietary fiber, vitamins, minerals and essential oils. These compounds contribute to various biological activities, including antioxidant, hepatoprotective, anti-inflammatory, antitumoral, analgesic, antidiabetic, skin healing, antidiarrhoeic, antimicrobial, antiparasitic, insecticide and herbicide activities of Annona crassiflora Mart. extracts. Therefore, these findings demonstrate that Annona crassiflora Mart. fruit, by-products and leaves can be excellent candidates to be used as functional foods and/or sources for obtaining bioactive compounds for the food, cosmetics and pharmaceutical applications.

Dietary polyphenols modulate starch digestion and glycaemic level: a review

Polyphenols, as one group of secondary metabolite, are widely distributed in plants and have been reported to show various bioactivities in recent year. Starch digestion not only is related with food industrial applications such as brewing but also plays an important role in postprandial blood glucose level, and therefore insulin resistance. Many studies have shown that dietary phenolic extracts and pure polyphenols can retard starch digestion in vitro, and the retarding effect depends on the phenolic composition and molecular structure. Besides, dietary polyphenols have also been reported to alleviate elevation of blood glucose level after meal, indicating the inhibition of starch digestion in vivo. This review aims to analyze how dietary polyphenols affect starch digestion both in vitro and in vivo. We can conclude that the retarded starch digestion in vitro by polyphenols results from inhibition of key digestive enzymes, including α-amylase and α-glucosidase, as well as from interactions between polyphenols and starch. The alleviation of postprandial hyperglycemia by polyphenols might be caused by both the inhibited starch digestion in vivo and the influenced glucose transport. Therefore, phenolic extracts or pure polyphenols may be alternatives for preventing and treating type II diabetes disease.

Effects of high-intensity ultrasound process parameters on the phenolic compounds recovery from araticum peel

In this work, we investigated the effects of the nominal ultrasonic power (160-640 W) and process time (0.5-5.0 min) on the phenolic compounds recovery and antioxidant activity from araticum peel. The individual and synergistic effects of the process variables on the phenolic recovery were estimated using a full factorial experimental design. Operating at high nominal ultrasonic powers was possible to obtain high phenolic yields and antioxidant activities at short process times (≤5 min). The HPLC-ESI-QTOF-MS/MS analysis revealed that the araticum peel sample possessed 142 phytochemicals, 123 of which had not been reported in the literature for this raw material yet. The most abundant phenolic compounds recovered were epicatechin, rutin, chlorogenic acid, catechin and ferulic acid. Thus, high-intensity ultrasound technology proved to be a simple, efficient, fast and low environmental impact method for obtaining phenolic compounds from araticum peel. In addition, araticum peel showed to be a promising source bioactive natural phenolics for further applications in the food, nutraceutical, cosmetic and pharmaceutical industries.

Antifungal and cytotoxicity activities of Banisteriopsis argyrophylla leaves

OBJECTIVES

This work aimed to evaluate the antifungal and cytotoxic activity of the EtOH extract and fractions of Banisteriopsis argyrophylla leaves, and to perform the identification of these bioactive metabolites.

METHODS

The EtOAc fraction (EAF) obtained from the ethanolic extract of B. argyrophylla leaves showed better antifungal potential against Candida spp. In this fraction, ten flavonoids have been identified by UHPLC-ESI-MSⁿ . Then, EAF was submitted to column chromatography to give four new fractions (A1-A4). The cytotoxicity was determined against Vero cells.

KEY FINDINGS

The EAF showed better antifungal potential against Candida spp. with minimum inhibitory concentrations (MICs) between 31.25 and 93.75 μg/ml. The (-)-catechin (fraction A1) showed a MIC of 2.83 μg/ml against Candida glabrata. Fractions A2, A3 and A4 were rich in quercetins and kaempferols and showed good inhibitory concentrations (5.86-46.87 μg/ml) against C. albicans, C. glabrata and C. tropicalis.

CONCLUSIONS

The EtOH extract, fractions and the isolated (-)-catechin showed lower toxicity to Vero cells than cisplatin, used as a positive control. Thus, the leaves of B. argyrophylla are a promising source of antifungal agents.

Antioxidant and anti-glycation capacities of some medicinal plants and their potential inhibitory against digestive enzymes related to type 2 diabetes mellitus

ETHNOPHARMACOLOGICAL RELEVANCE

Plants preparations are used by traditional medicine in the treatment of various diseases, such as type-2 diabetes mellitus. Some medicinal plants are capable of controlling the complications of this metabolic disease at different levels, for example, providing antioxidant compounds that act against oxidative stress and protein glycation and others which are capable of inhibiting the catalysis of digestive enzymes and thus contribute to the reduction of hyperglycemia and hyperlipidemia. Our objective was to investigate the antioxidant and anti-glycation activities of some medicinal plants and their potential inhibitory against α-amylase, α-glucosidase and pancreatic lipase activities.

MATERIAL AND METHODS

Based on the ethnobotanical researches carried out by academic studies conducted at the Federal University of Uberlandia, ten plants traditionally used in the treatment of type-2 diabetes mellitus were selected. Ethanol (EtOH) and hexane (Hex) extracts of specific parts of these plants were used in enzymatic assays to evaluate their inhibitory potential against α-amylase, α-glucosidase and lipase, as well as their antioxidant (DPPH, ORAC and FRAP) and anti-glycation (BSA/fructose model) capacities.

RESULTS

The results indicate that EtOH extract of four of the ten analyzed plants exhibited more than 70% of antioxidant and anti-glycation capacities, and α-amylase and lipase inhibitory activities; no extract was able to inhibit more than 40% the α-glucosidase activity. The EtOH extracts of Bauhinia forficata and Syzygium. cumini inhibited α-amylase (IC₅₀ 8.17 ± 2.24 and 401.8 ± 14.7 μg/mL, respectively), whereas EtOH extracts of B. forficata, Chamomilla recutita and Echinodorus grandiflorus inhibited lipase (IC₅₀ 59.6 ± 10.8, 264.2 ± 87.2 and 115.8 ± 57.1 μg/mL, respectively). In addition, EtOH extracts of B. forficata, S. cumini, C. recutita and E. grandiflorus showed, respectively, higher antioxidant capacity (DPPH IC₅₀ 0.7 ± 0.1, 2.5 ± 0.2, 1.3 ± 0.2 and 35.3 ± 9.0 μg/mL) and anti-glycation activity (IC₅₀ 22.7 ± 4.4, 246.2 ± 81.7, 18.5 ± 2.8 and 339.0 ± 91.0 μg/mL).

CONCLUSIONS

EtOH extracts of four of the ten species popularly cited for treatment of type 2 diabetes mellitus have shown promising antioxidant and anti-glycation properties, as well as the ability to inhibit the digestive enzymes α-amylase and lipase. Thus, our results open new possibilities for further studies in order to evaluate the antidiabetic potential of these medicinal plants.

Annona muricata Linn. leaf as a source of antioxidant compounds with in vitro antidiabetic and inhibitory potential against α-amylase, α-glucosidase, lipase, non-enzymatic glycation and lipid peroxidation

Annona muricata leaves are used in traditional medicine to manage diabetes mellitus and its complications. The aim of this study was to evaluate the potential in vitro antidiabetic properties of Annona muricata leaf by identifying its main phytochemical constituents and characterizing the phenolic-enriched fractions for their in vitro antioxidant capacity and inhibitory activities against glycoside and lipid hydrolases, advanced glycation end-product formation and lipid peroxidation. Ethanol extract of A. muricata leaf was subjected to a liquid-liquid partitioning and its fractions were used in enzymatic assays to evaluate their inhibitory potential against α-amylase, α-glucosidase and lipase, as well as their antioxidant (DPPH, ORAC, FRAP and Fe²⁺-ascorbate-induced lipid peroxidation assays) and anti-glycation (BSA-fructose, BSA-methylglyoxal and arginine-methylglyoxal models) capacities. In addition, identification of the main bioactive compounds of A. muricata leaf by HPLC-ESI-MS/MS analysis was carried out. Ethyl acetate (EtOAc) and n-butanol (BuOH) fractions showed, respectively, antioxidant properties (ORAC 3964 ± 53 and 2707 ± 519 μmol trolox eq g^-1, FRAP 705 ± 35 and 289 ± 18 μmol trolox eq g^-1, and DPPH IC₅₀ 4.3 ± 0.7 and 9.3 ± 0.8 μg mL^-1) and capacity to reduce liver lipid peroxidation (p < .01). Also, EtOAc and BuOH, respectively, inhibited glycation in BSA-fructose (IC₅₀ 45.7 ± 13.5 and 61.9 ± 18.2 μg mL^-1), BSA-methylglyoxal (IC₅₀ 166.1 ± 21.6 and 413.2 ± 49.5 μg mL^-1) and arginine-methylglyoxal (IC₅₀ 437.9 ± 89.0 and 1191.0 ± 199.0 μg mL^-1) assays, α-amylase (IC₅₀ 9.2 ± 2.3 and 6.1 ± 1.6 μg mL^-1), α-glucosidase (IC₅₀ 413.1 ± 121.1 and 817.4 ± 87.9 μg mL^-1) and lipase (IC₅₀ 74.2 ± 30.1 and 120.3 ± 50.5 μg.mL^-1), and presented lower cytotoxicity, when compared to the other fractions and crude extract. Various biomolecules known as potent antioxidants were identified in these fractions, such as chlorogenic and caffeic acids, procyanidins B2 and C1, (epi)catechin, quercetin, quercetin-hexosides and kaempferol. This study presents new biological activities not yet described for A. muricata, which contributes to the understanding of the potential effectiveness in the use of the A. muricata leaf, especially its polyphenols-enriched fractions, for the management of diabetes mellitus and its complications.

Determination of free, esterified, glycosylated and insoluble-bound phenolics composition in the edible part of araticum fruit (Annona crassiflora Mart.) and its by-products by HPLC-ESI-MS/MS

Phenolics present in the free, esterified, glycosylated and insoluble-bound forms of araticum pulp, peel and seed were for the first time characterized and quantified using HPLC-ESI-MS/MS. Levels of total phenolics, flavonoids, condensed tannins and antioxidant activities from araticum fruit followed the order peel > pulp > seed. Overall, insoluble-bound and esterified phenolics were the dominant forms of phenolics from araticum fruit parts and the highest contributors to their antioxidant activities. Extracts were found to contain contrasting levels of phenolics that were specific to each fruit part. From 10 phenolics quantified in araticum fruit, catechin and epicatechin were the major ones from pulp and peel, whereas seed displayed caffeic acid, catechin and epicatechin as its main phenolics. Araticum fruit was found to provide a good source of phenolics, and the full exploitation of this fruit may find applications in the food, cosmetic and pharmaceutical industries.

Compounds isolated from Eriobotrya deflexa leaves protect against ultraviolet radiation B-induced photoaging in human fibroblasts

Ultraviolet (UV) irradiation leads to skin photoaging because of the upregulation of matrix metalloproteinase (MMP)-1 and downregulation of type I collagen and tissue inhibitor of metalloproteinase (TIMP)-1. Eriobotrya deflexa (Hemsl.) Nakai (Rosaceae) is a flowering plant endemic to Taiwan, and its leaves have been used as an expectorant and in antitussive folk remedy. Our previous studies have demonstrated that an E. deflexa leaf extract functions as a free radical scavenger. The current evaluated the antiphotoaging effect of partitioned fractions and specific compounds from the leaves of E. deflexa by using bioguided isolation, compound identification, and biological activity testing with UVB-irradiated human fibroblasts (WS-1 cells). E. deflexa leaves were extracted with 95% ethanol and then partitioned using a sequential treatment of n-hexane, ethyl acetate, and n-butanol (n-BuOH). The bioactive n-BuOH fraction was used for isolation and purification through chromatography. The compounds were identified by analyzing their physical and spectroscopic properties. We identified eight compounds from this fraction; of these compounds, 3-O-α-l-rhamnopyranosyl-(1‴→6″)-β-d-galactopyranoside (1), hyperin (2), afzelin (5), and cryptochlorogenic acid methyl ester (7) were isolated from E. deflexa for the first time, and they exhibited MMP-1 inhibition activity. The IC₅₀ values were 96.5, 89.5, 93.4, and 92.8μM for 1, 2, 5, and 7, respectively. These compounds also enhanced the expression of procollagen type I, and TIMP-1 and hyperin (2) were found to be most effective with IC₅₀ values of 56.7 and 70.3μM, respectively. Hyperin (2) could reduce intracellular reactive oxygen species production in UVB-irradiated WS-1 cells, with the corresponding IC₅₀ value being 80.7μM. Liquid chromatography triple-quadrupole mass spectrometry was used for the quantitative and chemical fingerprint analysis of active compounds. Quercetin 3-O-α-l-rhamnopyranosyl-(1‴→6″)-β-d-galactopyranoside (1), hyperin (2), afzelin (5), and cryptochlorogenic acid methyl ester (7) constituted 24.2±3.9, 5.5±1.0, 3.4±0.3, and 67.1±8.1mg/g of dry weight in the active n-BuOH fraction, respectively. Our results demonstrate that the extract and the isolated active compounds from E. deflexa leaves possess the potential for protection against skin photoaging.

Hepatoprotective Properties of a Polyphenol-Enriched Fraction from Annona crassiflora Mart. Fruit Peel against Diabetes-Induced Oxidative and Nitrosative Stress

A polyphenol-enriched fraction from Annona crassiflora fruit peel (Ac-Pef) containing chlorogenic acid, (epi)catechin, procyanidin B2, and caffeoyl-glucoside was investigated against hepatic oxidative and nitrosative stress in streptozotocin-induced diabetic rats. Serum biochemical parameters, hepatic oxidative and nitrosative status, glutathione defense system analysis, and in silico assessment of absorption, distribution, metabolism, excretion, and toxicity (ADMET) of the main compounds of Ac-Pef were carried out. Ac-Pef treatment during 30 days decreased serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activities, as well as hepatic lipid peroxidation, protein carbonylation and nitration, inducible nitric oxide synthase level, and activities and expressions of glutathione peroxidase, superoxide dismutase, and catalase. There were increases in antioxidant capacity, glutathione reductase activity, and reduced glutathione level. ADMET predictions of Ac-Pef compounds showed favorable absorption and distribution, with no hepatotoxicity. A. crassiflora fruit peel showed hepatoprotective properties, indicating a promising natural source of bioactive molecules for prevention and therapy of diabetes complications.