LIPID EVALUATION OF SOME TUNISIAN CITRUS SEEDS

Nutrients and bioactives in citrus fruits: Different citrus varieties, fruit parts, and growth stages

Citrus fruits are consumed in large quantities worldwide due to their attractive aromas and taste, as well as their high nutritional values and various health-promoting effects, which are due to their abundance of nutrients and bioactives. In addition to water, carbohydrates, vitamins, minerals, and dietary fibers are important nutrients in citrus, providing them with high nutritional values. Citrus fruits are also rich in various bioactives such as flavonoids, essential oils, carotenoids, limonoids, and synephrines, which protect from various ailments, including cancer and inflammatory, digestive, and cardiovascular diseases. The composition and content of nutrients and bioactives differ significantly among citrus varieties, fruit parts, and growth stages. To better understand the nutrient and bioactive profiles of citrus fruits and provide guidance for the utilization of high-value citrus resources, this review systematically summarizes the nutrients and bioactives in citrus fruit, including their contents, structural characteristics, and potential health benefits. We also explore the composition variation in different citrus varieties, fruits parts, and growth stages, as well as their health-promoting effects and applications.

Fatty Acid Profile, Tocopherol Content of Seed Oil, and Nutritional Analysis of Seed Cake of Wood Apple (Limonia acidissima L.), an Underutilized Fruit-Yielding Tree Species

The present study was aimed at analyzing the fatty acid composition, tocopherols, and physico-chemical characterization of wood apple (Limonia acidissima L.) seed oil and the nutritional profile of seed cake. The fatty acids in seed oil were analyzed by gas chromatography–mass spectrometry (GC-MS), and the total seed oil was 32.02 ± 0.08%, comprising oleic (21.56 ± 0.57%), alpha-linolenic (16.28 ± 0.29%), and linoleic acid (10.02 ± 0.43%), whereas saturated fatty acid content was 33.38 ± 0.60% including palmitic (17.68 ± 0.65%) and stearic acid (14.15 ± 0.27%). A greater amount of unsaturated fatty acids (52.37%) were noticed compared to saturated fatty acids (33.38%); hence the seed is highly suitable for nutritional and industrial applications. Gamma-tocopherol was present in a higher quantity (39.27 ± 0.07 mg/100 g) as compared to alpha (12.64 ± 0.01 mg/100 g) and delta (3.77 ± 0.00 mg/100 g) tocopherols, which are considered as natural antioxidants. The spectrophotometric technique was used for quantitative analysis of total phenolic content, and it revealed 135.42 ± 1.47 mg gallic acid equivalent /100 g DW in seed cake. All the results of the studied seed oil and cake showed a good source of natural functional ingredients for several health benefits.

Extraction and Characterization of the Polar Lipid Fraction of Blackberry and Passion Fruit Seeds Oils Using Supercritical Fluid Extraction

The study of the phytochemical composition of seed oils is of upmost importance for the food and cosmetic industries, mainly considering their associated biological properties. Extraction of seed oils using supercritical fluids (SFE) is an ecological and green alternative to conventional extraction processes since it is able to provide with potent bioactive extracts, avoiding degradation and transformation of the compounds present originally in the raw material. The objective of the present work was the extraction of pure fractions of polar lipids and their chemical characterization using chromatographic techniques such as GC-MS and LC-DAD-MS/MS of blackberry (Rubus glaucus) and passion fruit (Passiflora edulis) seed oils extracted by supercritical carbon dioxide. Oleamides derived from oleic acid were identified as the main compounds in both samples; in particular, 9-octadecenamide was the major identified oleamide. Besides, the extract obtained from passion fruit showed to be a source of linoleic acid, while the SFE extract from blackberry presented important concentrations of vanillin. The chemical composition of these seed oils can be of high interest for their further use in cosmetics and food industry.

Fruit seeds and their oils as promising sources of value-added lipids from agro-industrial byproducts: oil content, lipid composition, lipid analysis, biological activity and potential biotechnological applications

Thousands of tons of fruit seeds are discarded every year worldwide as agro-industrial byproducts. Fruit seeds have a high oil content, are rich in monounsaturated fatty acids (FA) and in n-6 and n-3 polyunsaturated essential FA. Sterols, phospholipids, glycolipids, carotenoids, tocopherols and polyphenols are other seed phytochemicals that make them interesting from a commercial viewpoint. Fruit seeds have high potential as raw material for several industries, but their lipid profile remains poorly studied. Current analytical approaches for the analysis of lipids that are based on high-performance liquid chromatography and high-resolution mass spectrometry allow the separation and analysis of compounds with the accurate identification and structural characterization of molecular species in very small quantities. Even though lipidomic analysis of fruit seeds' lipids is still in its infancy, it will bring a new look over these value-added byproducts. This review covers the following topics: (a) the lipid content of various fruit seed oils; (b) their lipid composition (FA, triacylglycerol, sterol, phospholipid and glycolipid profiles), (c) current and future analytical methodologies for the analysis of lipids in fruit seeds; (d) biological activities of fruit seeds' extracts; and (e) potential biotechnological applications of fruit seed oils for their commercial valorization based on lipids.

Chemical characterization, antioxidant, cytotoxicity, Anti-Toxoplasma gondii and antimicrobial potentials of the Citrus sinensis seed oil for sustainable cosmeceutical production

There are growing concerns about the chronic and acute effects of synthetic additives such as antibacterial, fragrances, colourants and stabilizing agents used in the production of various household products. Many household products and materials including cosmetic products are reportedly suspected to be carcinogenic with some acting as endocrine disruptors among other effects. Thus, environmental-friendly alternatives such as products that are rich in bioactive phytochemicals are becoming consumers' preferred choice especially in the beauty and cosmetic sector. 'Green' preparation of medicinal soaps devoid of any synthetic additives was made from underutilized tropical seed of Citrus sinensis seed oil and some natural additives comprising of natural honey, Ocimum gratissimum leaves extract, Moringa oleifera seed oil and coconut oil. Precisely, the seed oil of the underexplored C. sinensis was obtained via soxhlet extraction and saponified with natural lye solution at different ratios to produce soaps of varying characteristics. The incorporation of honey and Ocimum gratissimum leaf extract provided additional antimicrobial, antioxidant and fragrance properties. Physico-chemical parameters of the oil and soaps were determined following standard procedures while the fatty acid profile of the trans-esterified oil was determined using GC-MS. The antimicrobial potential of the oil and soaps were assessed using agar diffusion method at concentrations 200 mg/mL and below. Linoleic acid (36%) and oleic acid (27%) were the most prominent in C. sinensis seed oil. The soap had antimicrobial potential comparable to commercial product. The soap samples recorded highest anti-bacteria activities (22.0 ± 1.0-23.0 ± 1.0) against Staphylococcus aureus and Bacillus subtilis and notable anti-fungi activities (18.0 ± 1.0) against Penicillium notatum and Candida albicans. Additionally, the oil showed moderate anti-parasite (anit-toxoplasma gondii) activity (EC50 ≤ 500 μg/mL) but with improved selectivity that precludes oxidative stress while the prepared medicinal soaps exhibited remarkable antioxidant property. The utilization of these locally sourced resources will prevent the daily introduction of synthetic antimicrobial and antioxidant chemicals into the environment. The initiative avail a sustainable production of environmentally-benign cosmetic products besides conversion of waste to wealth agrees which aligns with the Sustainable Development Goals (SDGs).

Comparing the effects of conventional and microwave roasting methods for bioactive composition and the sensory quality of cold-pressed orange seed oil

This study aims to report the composition of bioactives and volatile aromatic compounds, and determine the descriptive sensory properties of cold-pressed orange seed oil. The effects of oven pre-roasting and microwave pre-roasting of the seeds before cold pressing were compared. Thirteen sensory parameters were used to define the oil samples. The major bioactive components of the orange seed oils were naringin, hesperidin, and trans-ferulic acid. Flavonoids constituted the main phenolic class with 78.5% and 74.4%, followed by phenolic acids with 21.4% and 25.5% in the oven and microwave pre-roasted oil samples. The mean concentration of hesperidin and naringin varied from 903.4 to 909.6 mg/kg and from 234.3 to 299.8 mg/kg, respectively. The results showed for the first time in the literature that orange seed oil contains some volatile aromatic compounds and glycosylated flavanones that could have functional properties. Hence, cold-pressed orange seed oil could be suggested as the new potential health-promoting oil.

Cytotoxicity of 18 Cameroonian medicinal plants against drug sensitive and multi-factorial drug resistant cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Recommendations have been made stating that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account if selecting plants for anticancer screening, since these reflect disease states bearing relevance to cancer or cancer-like symptoms. Cameroonian medicinal plants investigated in this work are traditionally used to treat cancer or ailments with relevance to cancer or cancer-like symptoms.

AIM OF THE STUDY

In this study, 21 methanol extracts from 18 Cameroonian medicinal plants were tested in leukemia CCRF-CEM cells, and the best extracts were further tested on a panel of human cancer cell lines, including various multi-drug-resistant (MDR) phenotypes. Mechanistic studies were performed with the three best extracts.

MATERIALS AND METHODS

Resazurin reduction assay was used to evaluate cytotoxicity and ferroptotic effects of methanol extracts from different plants. Flow cytometry was used to analyze cell cycle, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) of extracts from Curcuma longa rhizomes (CLR), Lycopersicon esculentum leaves (LEL), and Psidium guajava bark (PGB).

RESULTS

In a pre-screening of all extracts, 13 out of 21 (61.9%) had IC₅₀ values below 80 µg/mL. Six of these active extracts displayed IC₅₀ values below 30 µg/mL: Cola pachycarpa leaves (CPL), Curcuma longa rhizomes (CLR), Lycopersicon esculentum leaves, Persea americana bark (PAB), Physalis peruviana twigs (PPT) and Psidium guajava bark (PGB). The best extracts displayed IC₅₀ values from 6.25 µg/mL (against HCT116 p53^-/-) to 10.29 µg/mL (towards breast adenocarcinoma MDA-MB-231-BCRP cells) for CLR, from 9.64 µg/mL (against breast adenocarcinoma MDA-MB-231 cells) to 57.74 µg/mL (against HepG2 cells) for LEL and from 1.29 µg/mL (towards CEM/ADR5000 cells) to 62.64 µg/mL (towards MDA-MB-231 cells) for PGB. CLR and PGB induced apoptosis in CCRF-CEM cells via caspases activation, MMP depletion and increase ROS production whilst LEL induced apoptosis mediated by caspases activation and increase ROS production.

CONCLUSION

The best botanicals tested were CLR and LEL, which are worth to be explored in more detail to fight cancers including MDR phenotypes.

The effect of drying temperatures on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol contents in citrus seed and oils

In this study, the effect of drying temperature on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol content of citrus seeds and oils were studied. Kinnow mandarin seed, dried at 60 °C, exhibited the highest antioxidant activity. Orlendo orange seed had the maximum total phenolic content and α-tocopherol content, with a value of 63.349 mg/100 g and 28.085 mg/g (control samples), respectively. The antioxidant activity of Orlendo orange seed (63.349%) was higher than seeds of Eureka lemon (55.819%) and Kinnow mandarin (28.015%), while the highest total phenolic content was found in seeds of Kinnow mandarin, followed by Orlendo orange and Eureka lemon (113.132). 1.2-Dihydroxybenzene (13.171), kaempferol (10.780), (+)-catechin (9.341) and isorhamnetin (7.592) in mg/100 g were the major phenolic compounds found in Kinnow mandarin. Among the unsaturated fatty acids, linoleic acid was the most abundant acid in all oils, which varied from 44.4% (dried at 80 °C) to 46.1% (dried at 70 °C), from 39.0% (dried at 60 °C) to 40.0% (dried at 70 °C). The total phenolic content, antioxidant activity and phenolic compounds of citrus seeds and tocopherol content of seed oils were significantly affected by drying process and varied depending on the drying temperature.

Antibacterial and Antibiotic-Modifying Activity of Methanol Extracts from Six Cameroonian Food Plants against Multidrug-Resistant Enteric Bacteria

The present work was designed to investigate the antibacterial activities of methanol extracts from six Cameroonian edible plants and their synergistic effects with some commonly used antibiotics against multidrug-resistant (MDR) Gram-negative bacteria expressing active efflux pumps. The extracts were subjected to qualitative phytochemical screening and the microdilution broth method was used for antibacterial assays. The results of phytochemical tests indicate that all tested crude extracts contained polyphenols, flavonoids, triterpenes, and steroids. Extracts displayed selective antibacterial activities with the minimal inhibitory concentration (MIC) values ranging from 32 to 1024 μg/mL. The lowest MIC value (32 μg/mL) was recorded with Coula edulis extract against E. coli AG102 and K. pneumoniae K2 and with Mangifera indica bark extract against P. aeruginosa PA01 and Citrus sinensis extract against E. coli W3110 which also displayed the best MBC (256 μg/mL) value against E. coli ATCC8739. In combination with antibiotics, extracts from M. indica leaves showed synergistic effects with 75% (6/8) of the tested antibiotics against more than 80% of the tested bacteria. The findings of the present work indicate that the tested plants may be used alone or in combination in the treatment of bacterial infections including the multidrug-resistant bacteria.

Cold pressed versus solvent extracted lemon (Citrus limon L.) seed oils: yield and properties

During the processing of lemon fruit, a large quantity of seeds is produced as a by-product. These seeds contain valuable components; therefore, required to be evaluated. This study aimed to compare the cold pressed with hexane-extracted lemon seed oils and determine their physicochemical and thermal properties. Cold pressing yielded significantly lower oil (36.84%) than hexane extraction (71.29%). In addition, the concentrations of free fatty acids, peroxides, and p-anisidine were lower in the cold pressed oil. Cold pressed oil showed higher total phenolics, α-tocopherol and antioxidant capacity. The major fatty acids found in the cold pressed oil were linoleic and palmitic acids, whereas β-sitosterol and campesterol were the dominant sterols. The crystallization and melting temperatures and enthalpies were also elucidated. In conclusion, this study proved that high quality of lemon seed oils can be produced by the cold pressing technique; this oil can be used in industries such as the food, cosmetic or chemical industries.

Effects of microwave roasting on the yield and composition of cold pressed orange seed oils

The aim of this study was to valorize orange (Citrus sinensis) seeds, which are generated as waste. This study presents data about raw orange seed, the meal gained after cold pressing, and characterization data of the cold pressed seed oils. Furthermore, the effects of microwave roasting of the seds compared to regular roasting (control) were determined. The oil yield of orange seed cold pressing was around 52.93–62.99%. After cold pressing, 13.57–17.97% oil remained in the meal together with 20.68–25.61% protein. Hence, pressed meals could be valorized for different purposes. Except for turbidity, the color b* value, free acidity, the p-anisidine value and antioxidant capacity, there was no significant difference between the two oil samples for the measured physicochemical properties. Six different fatty acids were quantified and the major fatty acids were linoleic, palmitic and oleic acids. The fatty acid composition of the orange seed oil can be accepted as nutritionally balanced. Among the fifteen sterols quantified, ß-sitosterol was dominant (around 77–78%). Likewise, the α-tocopherol content of the samples was not significantly different. The thermal onset and peak temperatures, and enthalpies for crystallization and melting were also reported. This study showed that good quality orange seed oils can be produced by cold pressing, and the oils could be used in food and non-food applications.

The physico-chemical properties of some citrus seeds and seed oils

The chemical properties, mineral contents, fatty acid and tocopherol contents of seed and seed oils of some citrus genus provided from several locations in Turkey and Saudi Arabia were determined. While Ca contents of seeds were between 5018 mg/kg (Kütdiken lemon) and 7619 mg/kg (kinnow mandarin), K contents of seeds varied between 7007 mg/kg (Orlando orange) and 10334 mg/kg (kinnow mandarin). Glucose and fructose contents of citrus seed samples varied between 3.75 g/kg and 5.75 g/kg, and 4.09 g/kg and 6.03 g/kg. Palmitic, oleic and linoleic acids were established as dominant fatty acids. Palmitic, oleic and linoleic acid contents of citrus seed oils varied between 19.6% (Kütdiken lemon) and 26.2% (pineapple orange), 21.3% (kinnow mandarin) and 31.4% (Kütdiken lemon) and 32.3% (Kütdiken lemon) and 43.7% (kinnow mandarin), respectively. The total amount of tocopherols of Turkish citrus oil varied between 0.5 mg/100 g (Fremont mandarin) and 18.8 mg/100 g (bitter orange).

Physicochemical characteristics of citrus seed oils from kerman, iran

Recently, there has been a great deal of attention on usage, byproducts, and wastes of the food industry. There have been many studies on the properties of citrus seeds and extracted oil from citrus grown in Kerman, Iran. The rate of oil content of citrus seeds varies between 33.4% and 41.9%. Linoleic acid (33.2% to 36.3%) is the key fatty acid found in citrus seeds oil and oleic (24.8% to 29.3%) and palmitic acids (23.5% to 29.4%) are the next main fatty acids, respectively. There are also other acids found at trivial rates such as stearic, palmitoleic, and linolenic. With variation between 0.54 meg/kg and 0.77 mgq/kg in peroxide values of citrus seed oils, acidity value of the oil varies between 0.44% and 0.72%. The results of the study showed that citrus seeds under study (orange and sour lemon grown in Kerman province) and the extracted oil have the potential of being used as the source of edible oil.