Fermented curly kale as a new source of gentisic and salicylic acids with antitumor potential

Fermenting kale (Brassica oleracea L.) enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors

The properties of kale as a functional food are well established. We sought to determine how fermentation further enhances these properties. We tested different fermentation conditions: (i) spontaneous fermentation with naturally occurring bacteria, (ii) spontaneous fermentation with 2% salt, (iii) Lactococcus lactis, (iv) Lactobacillus acidophilus, (v) mixture of L. lactis and L. acidophilus, (vi) mixture of L. lactis, L. acidophilus, and Clostridium butyricum. We quantified selected bioactive components using high-performance liquid chromatography (HPLC) and antinutritional factors using a gravimetric method and spectrophotometry. We then determined (i) the antioxidant capacity of the vegetable, (ii) anti-inflammation capacity, and (iii) the surface microbiota composition by 16S sequencing. All fermentation methods imparted some benefits. However, fermentation with mixed culture of L. lactis and L. acidophilus was most effective in increasing polyphenols and sulforaphane accessibility, increasing antioxidant activity, and reducing antinutritional factors. Specifically, fermentation with L. lactis and L. acidophilus increased total polyphenols from 8.5 to 10.7 mgGAE/g (milligrams of gallium acid equivalent per gram) and sulforaphane from 960.8 to 1777 μg/g (microgram per gram) but decreased the antinutritional factors oxalate and tannin. Total oxalate was reduced by 49%, while tannin was reduced by 55%-65%. The antioxidant capacity was enhanced but not the anti-inflammation potential. Both unfermented and fermented kale protected equally against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and prevented increases in inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 messenger RNA (IL-6 mRNA) expression by 84.3%, 62%, 68%, and 85.5%, respectively. Unfermented and naturally fermented kale had high proportions of sulfur reducing Desulfubrio and Proteobacteria usually associated with inflammation. Fermenting with L. lactis and/or L. acidophilus changed the bacterial proportions, reducing the Proteobacteria while increasing the genera Lactobacilli and Lactococcus. In summary, fermentation enhances the well-known beneficial impacts of kale. Fermentation with mixed cultures of L. lactis and L. acidophilus imparts higher benefits compared to the single cultures or fermentation with native bacteria present in the vegetable.

Studies on the Effects of Fermentation on the Phenolic Profile and Biological Activity of Three Cultivars of Kale

Fermentation is used not only to preserve food but also to enhance its beneficial effects on human health and achieve functional foods. This study aimed to investigate how different treatments (spontaneous fermentation or fermentation with the use of starter culture) affect phenolic content, antioxidant potential, and cholinesterase inhibitory activity in different kale cultivars: 'Halbhoner Grüner Krauser', 'Scarlet', and 'Nero di Toscana'. Chosen samples were further tested for their protective potential against the Caco-2 cell line. HPLC-MS analysis revealed that the fermentation affected the composition of polyphenolic compounds, leading to an increase in the content of rutin, kaempferol, sinapinic, and protocatechuic acids. In general, kale cultivars demonstrated various antioxidant activities, and fermentation led to an increase in total phenolic content and antioxidant activity. Fermentation boosted anti-cholinesterase activity most profoundly in 'Nero di Toscana'. Extracts of spontaneously fermented 'Scarlet' (SS) and 'Nero di Toscana' (NTS) showed cytoprotective properties, as revealed by the malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) assays. Additionally, strong anti-inflammatory activity of NTS was shown by decreased release of cytokines IL-1β and TNF-α. Collectively, the conducted studies suggest fermented kale cultivars as a potential source for functional foods.

Tumour-specific hybrid nanoparticles in therapy of breast cancer

In this study, salicylic acid (SA) dopped into poly(3-hydroxybutyrate) (PHB) and prepared nanoparticles (NPs) to increase encapsulation efficiency, anti-cancer activity of caffeic acid (Caff), and folic acid (FA) for breast cancer treatment. NPs were prepared by solvent evaporation method and characterised by FTIR, DSC, SEM, and entrapment-loading efficiencies. The mean diameter, polydispersity index (PDI), and zeta potential (ZP) were evaluated by dynamic light scattering (DLS). In vitro release and stability studies were done via eppendorf method. The cytotoxicity, cell dead and internalisation of NPs were shown by MTT, fluorescein and confocal microscopy. The diameter and ZP of NPs were 172 ± 7 nm and -29 ± 0.38 mV. The entrapment efficiencies of 5 and 10 Caff NPs were 79 ± 0.23% and 70 ± 0.42%. NPs showed good stability within 30 d and sustained release over 25 d. FA-5Caff NPs showed 37 ± 0.3% viability on MCF-7. FA-Caff NPs were identified as promising carrier system for breast cancer therapy.

Synergistic Antioxidant and Anti-Inflammatory Activities of Kale Juice Fermented with Limosilactobacills reuteri EFEL6901 or Limosilactobacills fermentum EFEL6800

This study investigates the synergistic impact of fermenting kale juice with Limosilactobacillus strains on its antioxidant and anti-inflammatory properties. Kale's rich nutrient profile, especially its flavonoids, offers potential health benefits. Probiotic lactic acid bacteria are employed in kale fermentation to enhance nutrient bioavailability and generate bioactive compounds. Kale juices fermented with L. reuteri EFEL6901 or L. fermentum EFEL6800 exhibited superior microbial growth. Free sugars and amino acids were converted to alcohols and organic acids, affecting the organoleptic and health-related properties of the product. In addition, fermentation increased quercetin and kaempferol content, indicating improved availability. Furthermore, the fermented juice exhibited notable antioxidant activity and suppressed nitric oxide (NO) production, revealing anti-inflammatory potential. Gene expression analysis confirmed reduced pro-inflammatory markers such as iNOS, COX-2, IL-6, and IL-1β and elevated anti-inflammatory cytokines, including IL-10. This research highlights the promising potential of fermented kale juice, enriched with Limosilactobacillus strains, as a functional food with combined antioxidant and anti-inflammatory benefits.

Exploring the Anti-Cancer Effects of Fish Bone Fermented Using Monascus purpureus: Induction of Apoptosis and Autophagy in Human Colorectal Cancer Cells

Fish bone fermented using Monascus purpureus (FBF) has total phenols and functional amino acids that contribute to its anti-oxidant and anti-inflammatory properties. Colorectal cancer, one of the most prevalent cancers and the third largest cause of death worldwide, has become a serious threat to global health. This study investigates the anti-cancer effects of FBF (1, 2.5 or 5 mg/mL) on the cell growth and molecular mechanism of HCT-116 cells. The HCT-116 cell treatment with 2.5 or 5 mg/mL of FBF for 24 h significantly decreased cell viability (p < 0.05). The S and G2/M phases significantly increased by 88-105% and 25-43%, respectively (p < 0.05). Additionally, FBF increased the mRNA expression of caspase 8 (38-77%), protein expression of caspase 3 (34-94%), poly (ADP-ribose) polymerase (PARP) (31-34%) and induced apoptosis (236-773%) of HCT-116 cells (p < 0.05). FBF also increased microtubule-associated protein 1B light chain 3 (LC3) (38-48%) and phosphoinositide 3 kinase class III (PI3K III) (32-53%) protein expression, thereby inducing autophagy (26-52%) of HCT-116 cells (p < 0.05). These results showed that FBF could inhibit HCT-116 cell growth by inducing S and G2/M phase arrest of the cell cycle, apoptosis and autophagy. Thus, FBF has the potential to treat colorectal cancer.

Antioxidant and Antiproliferative Activities of Kale (Brassica oleracea L. Var. acephala DC.) and Wild Cabbage (Brassica incana Ten.) Polyphenolic Extracts

Brassicaceae are rich in healthy phytochemicals that have a positive impact on human health. The aim of this study was to analyze the phenolic compounds and antioxidant and anticancer potential of traditional Croatian kale (Brassica oleracea L. var. acephala DC.) and wild cabbage (Brassica incana Ten.) extracts. The phenolic groups and antioxidant activity were determined by spectrophotometry, selected phenolic compounds (ferulic acid, sinapic acid, salicylic acid, kaempferol, and quercetin) were analyzed by LC-MS/MS, and anticancer potential was evaluated in vitro using HeLa cells. The extracts of both plant species are rich in phenolic compounds and showed significant antioxidant activity at similar levels. LC-MS/MS detected sinapic acid as the most abundant phenolic acid, followed by ferulic acid, while salicylic acid was present at lower concentrations. A comparative analysis showed that wild cabbage contained significantly more sinapic acid, while kale contained more kaempferol and quercetin. Both Brassica extracts at a concentration of 50 µg mL^-1 showed an antiproliferative effect on HeLa cells, while they did not affect the proliferation of normal human skin fibroblasts. Wild cabbage extract also showed an antiproliferative effect on HeLa cells at a lower applied concentration of 10 µg mL^-1 of extracts. The clonogenic analysis also revealed the inhibitory effect of the extracts on HeLa colony growth.

Changes in the content of glucosinolates, polyphenols and carotenoids during lactic-acid fermentation of cruciferous vegetables: a mini review

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Cruciferous vegetables as fermented products has been used since ancient times.

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During fermentation of cruciferous vegetables complete fermentation of glucosinolates occur.

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Fermentation decrease the content of complex polyphenols, while increase the content of polyphenols in free form.

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Carotenoid content decrease during fermentation of cruciferous vegetables.

Cruciferous vegetables are considered functional foods because of their content of health-related compounds. They are grown and consumed in various cultures around the world. Fermentation as a preservation method for cruciferous vegetables has been used since ancient times. This process results in fermented products that have a unique flavour and odour, high bioactivity, and a distinctly different phytochemical profile than raw vegetables. In this mini review, we summarize data on changes in phytochemical content during lactic-acid fermentation of various cruciferous vegetables. The main focus was on the changes in the group of glucosinolates, polyphenols and carotenoids.

Changes in Phenolic Profiles and Inhibition Potential of Macrophage Foam Cell Formation during Noni (Morinda citrifolia Linn.) Fruit Juice Fermentation

The dynamic changes in phenolic composition and antioxidant activity, and the potential effect on foam cell formation and cholesterol efflux during noni (Morinda citrifolia Linn.) fruit juice fermentation were investigated in this study. The composition of phenolic compounds was significantly different at various fermentation times. Rutin, quercetin, and isoquercitrin were the major phenolics in fermented noni fruit juice based on a quantitative analysis of representative phenolics. The contents of caffeic acid, 2,4-dihydroxybenzoic acid, p-coumaric acid, rutin, and quercetin tended to increase, while those of isoquercitrin decreased during the fermentation process. Fermented noni juice extracts showed high antioxidant activities against 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), hydroxyl radical scavenging activity, and ferric reducing antioxidant power. Notably, the highest antioxidant activity was observed after 28 days of fermentation. Furthermore, the treatment of fermented noni juice extracts was shown to reduce foam cell formation, intracellular cholesterol level, and the cholesterol esterification ratio. A correlation analysis indicated a strong positive relationship between the phenolic composition, antioxidant activity, and the ratio of cholesterol ester and total cholesterol. This study may provide a theoretical basis for the quality improvement and standardized production of fermented noni fruit juice, thus promoting the development of the noni food industry.

Multitherapeutic Efficacy of Curly Kale Extract Fabricated Biogenic Silver Nanoparticles

Purpose

Due to the biomedical applications universally, the Ag nanoparticles are one of the most commonly investigated nanoparticles (NPs). Curly kale (BroL) leaves contain numerous beneficial nutrients and phytochemicals. The aim of the current study is the fabrication of the Ag nanoparticles using the extracts of curly kale and to investigate their biological potentials.

Methods

The characterization of the generated BroLAgNPs was done through UV-Vis spectro study, Fourier-transform infrared spectro study, scanning electron microscope analysis, energy-dispersive X-ray study, distribution of size and zeta potential investigation, and X-ray powder diffraction study, and their biological effects were evaluated by antidiabetic, antioxidant, antibacterial and cytotoxicity effect.

Results

BroL-Ag nanoparticle displayed surface plasmon resonance at 432 nm. The Zeta potential of BroL (-26.6) AgNPs displayed a highly negative charge. In antidiabetic assay, BroL-AgNPs was highly effective with IC50 value 2.29 µg/mL at 1.0 µg/mL concentration. In cytotoxicity assay, BroL-AgNPs displayed strong activity at 10.0 µg/mL concentration. It showed inhibitory action against three food-borne pathogenic bacteria (9.29-11.44 mm inhibition zone) and displayed moderate antioxidant potential.

Conclusion

This study as a whole report an eco-friendly green synthesis of AgNPs using leafy vegetable aqueous extract and its multi-biological effects which could serve as a promising candidate in pharmacological and related industries.

Effects of humate and neodymium on phytochemical levels in kale at different ontogenetic stages

The increased global mortality caused by the rise in chronic diseases can be reduced by the consumption of antioxidant-rich foods. Leafy green kale (Brassica oleracea var. sabellica) has high nutritional value due to its high antioxidant content and its consumption is highly correlated with a reduced risk of developing some chronic diseases. The paper focuses on examining the effects of two different mineral nutrients – neodymium and potassium humate – on the accumulation of flavonoids, vitamin C, phenolic compounds, carotenoids and malondialdehyde (MDA) content in field-grown leafy green kale. Leaves from treated plants were collected at three stages of maturity –14 weeks, 18 weeks, and 22 weeks and subjected to spectrophotometric analysis. The results showed that the stimulatory effect of both mineral nutrients on the phytochemicals varied at the different growth stages - the highest significant effect of neodymium has been mostly observed at week 18 with high flavonoid, vitamin C, and carotenoid levels. Phenolic compounds for this variant are the same as in the control samples, while the level of malondialdehyde was reduced by 21.8%, signifying increased antioxidant activity. The rare earth element primarily maintained some phytochemical content at weeks 14 and 22. Following soil treatment with potassium humate, the levels of studied phytochemical compounds were either maintained or elevated at weeks 14, 18, and 22. Humic acid exerted the greatest decrease in malondialdehyde content in kale at week 14, indicating a reduction in the lipid peroxidation process in leaves. Accordingly, the harvest date of leafy green kale (Brassica oleracea var. sabellica) should depend on the type of mineral nutrient applied. The obtained results provide information that may be relevant to the production of functional varieties and enhance the nutritional and possibly the economic value of kale.

Controlled fermentation of curly kale juice with the use of autochthonous starter cultures

The aim of this paper was to evaluate the influence of different indigenous lactic acid bacteria isolates - as a single culture or bacterial consortium - on the functional and physicochemical properties of fermented curly kale juice. All tested variants exhibited good growth parameters, manifested by efficient pH lowering, increases in acidity, and fructose and glucose metabolism, as well as a significant inhibition of pathogens. A slight increase in total phenolic content was observed, while antioxidant activity remained unchanged. L. sakei and MIX A were associated with an increase in riboflavin and pyridoxine content, while L. plantarum only contributed to an increase in vitamin B₆ content. Bioconversion of individual phenolic compounds, carotenoids, and glucosinolates strongly depended on the strain-specific metabolism. In the process, the levels of ferulic acid and other hydroxycinnamic acids were maintained, while the content of 9-cis lutein increased. Considering presented results and our previous research regarding probiotic features of LAB strains, among tested starter cultures - L. plantarum seemed to possess the best characteristics as a potential starter culture for controlled fermentation of curly kale juice.

Development of a High-Fibre Multigrain Bar Technology with the Addition of Curly Kale

The aim of this study was to find the effect of kale and dietary fibre (DF) on the physicochemical properties, nutritional value and sensory quality of multigrain bars. A recipe of multigrain bars was prepared with the addition of fresh kale (20% and 30%) and DF preparations (apple, blackcurrant, chokeberry and hibiscus). The bars were baked at 180 °C for 20 min. These snack bars, based on pumpkin seeds, sunflower seeds, flaxseed and wholegrain oatmeal, are a high-calorie product (302-367 kcal/100 g). However, the composition of the bars encourages consumption. In addition to the ability to quickly satisfy hunger, such bars are rich in many natural ingredients that are considered pro-health (high fibre content (9.1-11.6 g/100 g), protein (11.2-14.3 g/100 g), fat (17.0-21.1 g/100 g, including unsaturated fatty acids), carbohydrates (20.5-24.0 g/100 g), as well as vitamins, minerals and a large number of substances from the antioxidant group. The addition of kale caused a significant increase of water content, but reduction in the value of all texture parameters (TPA profiles) as well as calorific values. The content of polyphenols was strongly and positively correlated with the antioxidant activity (r = 0.92). In the bars with 30% addition of kale (422 mg GA/100 g d.m.), the content of polyphenols was significantly higher than based ones (334 mg GA/100 g d.m.). Bars with the addition of the DF were characterized by a higher antioxidant activity, and the content of carotenoids, chlorophyll A and B and polyphenols. High sensory quality was demonstrated for all (from 4.8 to 7.1 on a 10-point scale). The addition of fibre preparations was also related to technological aspects and allows to create attractive bars without additional chemicals.

Ethnomycological Investigation in Serbia: Astonishing Realm of Mycomedicines and Mycofood

This study aims to fill the gaps in ethnomycological knowledge in Serbia by identifying various fungal species that have been used due to their medicinal or nutritional properties. Ethnomycological information was gathered using semi-structured interviews with participants from different mycological associations in Serbia. A total of 62 participants were involved in this study. Eighty-five species belonging to 28 families were identified. All of the reported fungal species were pointed out as edible, and only 15 of them were declared as medicinal. The family Boletaceae was represented by the highest number of species, followed by Russulaceae, Agaricaceae and Polyporaceae. We also performed detailed analysis of the literature in order to provide scientific evidence for the recorded medicinal use of fungi in Serbia. The male participants reported a higher level of ethnomycological knowledge compared to women, whereas the highest number of used fungi species was mentioned by participants within the age group of 61–80 years. In addition to preserving ethnomycological knowledge in Serbia, this study can present a good starting point for further pharmacological investigations of fungi.

Transepithelial Anti-Neuroblastoma Response to Kale among Four Vegetable Juices Using In Vitro Model Co-Culture System

Juicing vegetables is thought to be an anticancer treatment. Support exists for a rank order of anticancer greens (kale > dandelion > lettuce > spinach) based on degrees of bioavailability of different phytochemicals, also offset by some noxious molecules (i.e., calcium-oxalate). We developed a new in vitro transepithelial anti-neuroblastoma model system. The juices were diluted as predicted once in the small intestine. They were applied to apical Caco-2Bbe1 cells atop dividing SH-SY5Y neuroblastoma cells, and changes in transepithelial electrical resistance (TEER) and cell growth were considered with juice spectroscopies. Studied first in monoculture, kale and dandelion were the most cytostatic juices on SH-SY5Ys, lettuce showed no effect, and high (4.2%) spinach was cytotoxic. In co-culture, high (4.2%) kale was quickest (three days) to inhibit neuroblastoma growth. By five days, dandelion and kale were equally robust. Lettuce showed small anti-proliferative effects at five days and spinach remained cytotoxic. Spinach’s cytotoxicity corresponded with major infrared bands indicative of oxalate. Kale juice uniquely induced reactive oxygen species and S-phase cell cycle arrest in SH-SY5Y. The superiority of kale and dandelion was also apparent on the epithelium, because raising TEER levels is considered healthy. Kale’s unique features corresponded with a major fluorescent peak that co-eluted with kaempferol during high performance liquid chromatography. Because the anticancer rank order was upheld, the model appears validated for screening anticancer juices.

Gentisic acid prevents diet-induced obesity in mice by accelerating the thermogenesis of brown adipose tissue

Gentisic acid prevents diet-induced obesity in mice by accelerating the thermogenesis of brown adipose tissue.

The Effect of Different Extraction Protocols on Brassica oleracea var. acephala Antioxidant Activity, Bioactive Compounds, and Sugar Profile

The extraction of glucosinolates in boiling aqueous methanol from freeze dried leaf tissues is the most common method for myrosinase inactivation but can be hazardous because of methanol toxicity. Although freeze drying is the best dehydration method in terms of nutritional quality preservation, the main drawbacks are a limited sample quantity that can be processed simultaneously, a long processing time, and high energy consumption. Therefore, the aim of this study is to evaluate the effects of applying high temperature for myrosinase inactivation via hot air drying prior to the extraction step, as well as the effects of cold aqueous methanol extraction on total antioxidant activity, total glucosinolates, total phenolic content, and sugar profile in 36 landraces of kale. The results from our study indicate that cold aqueous methanol can be used instead of boiling aqueous methanol with no adverse effects on total glucosinolate content. Our results also show that hot air drying, compared to freeze drying, followed by cold extraction has an adverse effect on antioxidant activity measured by DPPH radical scavenging, total glucosinolate content, as well as on the content of all investigated sugars.

The value of bioactive compounds of cruciferous vegetables (Brassica) as antimicrobials and antioxidants: A review

Nowadays, consumers are demanding nutrient-rich products for health optimal benefits. In this regard, Brassicaceae family plants, previously named cruciferous, group a large number of widely consumed species around the world. The popularity of Brassica is increasing due to their nutritional value and pharmacological effects. The group includes a large number of vegetable foods such as cabbages, broccoli, cauliflower, mustards as well as, oilseed rapeseed, canola, among others. In recent years, the phytochemical composition of Brassicaceae has been studied deeply because they contain many valuable metabolites, which are directly linked to different recognized biological activities. The scientific evidence confirms diverse medical properties for the treatment of chronic diseases such as obesity, type-2 diabetes, cardiovascular diseases (hypertension, stroke), cancer, and osteoporosis. The unique features of Brassicaceae family plants conferred by their phytochemicals, have extended future prospects about their use for beneficial effects on human nutrition and health worldwide. PRACTICAL APPLICATIONS: For years, the Brassicaceae plants have been a fascinating research topic, due to their chemical composition characterized by rich in bioactive compounds. The implementation of extracts of these vegetables, causes various beneficial effects of high biological value in the treatment of diseases, owing to their bioactive properties (anti-obesity, anticancer, antimicrobial, antioxidant, hepatoprotective, cardioprotective, gastroprotective, anti-inflammatory, antianemic, and immunomodulator). Therefore, this review summarizes the chemical composition, describes the bioactive compounds isolated in the plant extracts, and highlights diverse biological activities, mainly the antimicrobial and antioxidant capacity. Brassica plants, as source of natural bioactive agents, have a great potential application to improve the human nutrition and health.

Comprehensive LC-MS/MS-based phytochemical perspectives and osteogenic effects of Uraria crinita

Osteogenesis plays a vital role in the maintenance of bone health. Imbalances in osteogenesis influence the onset of several bone loss-associated diseases. The intake of Uraria crinita (Fabaceae) through dietary supplements is advised for childhood bone dysplasia. This botanical provides edible tonics and detoxifiers, and is also used as a folk beverage. We evaluated the osteogenic effects of a 50% ethanol extract of the root of U. crinita on primary human osteoblasts (HObs) and initiated a novel comprehensive phytochemical strategy using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quality control of this functional food. Two isoflavones, genistein (5) and 5,7-dihydroxy-3',5'-dihydroxyisoflavone (6), increased the alkaline phosphatase activity (differentiation stage); the flavone glycoside vitexin (1), and the phenolic acid salicylic acid (2) enhanced the mineralization (mature stage). The isoflavone 2'-hydroxygenistein (4) possessed high osteogenic potential among the isolated compounds in HObs. It promoted osteogenesis-related stages and upregulated the gene expressions in a dose-dependent manner. The major compounds in the active fraction were quantitatively analyzed via phytochemical fingerprint detection. These LC-MS/MS-based phytochemical perspectives can act as reference standards in developing food supplements from U. crinita.