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The rising concentration of CO2 in the atmosphere is approaching critical levels, posing a significant threat to life on Earth. Porous carbons derived from biobased materials, particularly waste byproducts, offer a viable solution for selective CO2 adsorption from large-scale industrial sources, potentially mitigating atmospheric CO2 emissions. In this study, we developed highly porous carbons from lemon peel waste through a two-step process, consisting of temperature pretreatment (500 °C) followed by chemical activation by KOH at 850 °C. The largest specific surface area (2821 m2/g), total pore volume (1.39 cm3/g), and micropore volume (0.70 cm3/g) were obtained at the highest KOH-to-carbon ratio of 4. In contrast, the sample activated with a KOH-to-carbon ratio of 2 demonstrated the greatest micropore distribution. This activated biocarbon exhibited superior CO2 adsorption capacity, reaching 5.69 mmol/g at 0 °C and 100 kPa. The remarkable adsorption performance can be attributed to the significant volume of micropores with diameters smaller than 0.859 nm. The Radke–Prausnitz equation, traditionally employed to model the adsorption equilibrium of organic compounds from liquid solutions, has been shown to be equally applicable for describing the gas–solid adsorption equilibrium. Furthermore, equations describing the temperature dependence of the Radke–Prausnitz equation's parameters have been developed. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to optimize the preparation process of polysaccharides from lemon peel and screen out the components with high hypoglycemic activity. Methods: Ultrasonic assisted enzymatic extraction of lemon peel polysaccharide, combined with response surface test to explore the best extraction process, through DEAE-52 anion chromatography and Sephadex G-100 gel column chromatography separation and purification to obtain a homogeneous polysaccharide fraction (named as LPs-1a). The effective hypoglycemic components of lemon peel polysaccharides were screened by α-glucosidase and their relative molecular weight, monosaccharide composition and characteristic groups were analyzed. Results: The optimal extraction process of lemon peel polysaccharide was ultrasonic treatment for at 55 ℃ for 44 min with solid-liquid ratio 1∶20 (g/mL) and cellulase addition rate 1.1%. Under the control of these conditions, the yield of lemon peel polysaccharide was 6.83%, which was close to the predicted value. The LPs-1a fraction significantly inhibited the activity of α-glucosidase with （1.22±0.04） mg/mL of IC50(P＜0.05). The relative molecular weight of this component was 195 260, and it was connected by α-glycosidic bonds and β-glycosidic bonds with a pyranose ring. The morphology of the polysaccharide was fibrous, and it was composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose and arabinose Conclusion: Ultrasound-assisted enzymatic method is helpful in screening the highly hypoglycemic active components of lemon peel polysaccharides.

The Food and Agricultural Organization estimates a 17% loss in the food production chain, making it imperative to adopt scientific and technological approaches to address this issue for sustainability. Industrial food production waste and its value-added applications, particularly in relation to a wide variety of pathogenic microorganisms and the health-related effects have not been thoroughly investigated. This study explores the potential of food production waste extracts—lemon peel (LP), hot trub (HT), and coffee silverskin (CSS) as sources of bioactive compounds. Extraction was conducted using hydro-methanolic extraction with yields in LP (482 mg/1 g) > HT (332 mg/1 g) > CSS (20 mg/1 g). The agar diffusion assay revealed the substantial antibacterial activity of all three extracts against Erwinia Amylovora, Escherichia coli, Bacillus subtilis, and Bacillus aquimaris. All extracts demonstrated activity against Gram-positive and Gram-negative bacteria, displaying minimum inhibitory concentrations effective against pathogenic bacteria like Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella enterica. Total phenolic content (TPC in mg GAE/1g) was 100, 20, and 100 for CSS, HT, and LP, respectively. Antioxidant activity by ABTS indicated IC50 of 3.09, 13.09, and 2.61 for LP, HT, and CSS, respectively. Also, the antioxidant activity of the extracts was further confirmed by DPPH assay with the best activity in CSS (9.84 GAEg−1) and LP (9.77 mg of GAEg−1) rather than in HT (1.45 GAEg−1). No adverse cytotoxic effects on HaCaT cells were observed. Pancreatic amylase inhibition demonstrated antidiabetic potential, with LP showing the highest levels (92%). LC-MS characterization identified polyphenols as the main compounds in CSS, prenylated compounds in HT, and flavanols in LP. The findings imply the potential sustainable use of food production waste in industry. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rising concentration of CO2 in the atmosphere is approaching critical levels, posing a significant threat to life on Earth. Porous carbons derived from biobased materials, particularly waste byproducts, offer a viable solution for selective CO2 adsorption from large-scale industrial sources, potentially mitigating atmospheric CO2 emissions. In this study, we developed highly porous carbons from lemon peel waste through a two-step process, consisting of temperature pretreatment (500 °C) followed by chemical activation by KOH at 850 °C. The largest specific surface area (2821 m2/g), total pore volume (1.39 cm3/g), and micropore volume (0.70 cm3/g) were obtained at the highest KOH-to-carbon ratio of 4. In contrast, the sample activated with a KOH-to-carbon ratio of 2 demonstrated the greatest micropore distribution. This activated biocarbon exhibited superior CO2 adsorption capacity, reaching 5.69 mmol/g at 0 °C and 100 kPa. The remarkable adsorption performance can be attributed to the significant volume of micropores with diameters smaller than 0.859 nm. The Radke–Prausnitz equation, traditionally employed to model the adsorption equilibrium of organic compounds from liquid solutions, has been shown to be equally applicable for describing the gas–solid adsorption equilibrium. Furthermore, equations describing the temperature dependence of the Radke–Prausnitz equation’s parameters have been developed.

The concentration of CO2 in the atmosphere has been increasing and is soon to reach a threatening level for life on the planet. Porous carbons made from biobased materials including from waste resources can be applied to selectively adsorb CO2 from large industrial sites and then lower atmospheric CO2 emissions. In this work, we synthesized highly porous carbons from lemon-peel wastes using two-step activation process involving hydrothermal carbonization followed by chemical activation with KOH, and KOH + alum at 800 °C. The sample activated with KOH + alum has the highest BET surface area (2143 m2/g) and total pore volume of 1.3 cc/g. Although the KOH activated sample has a lower surface area (1113 m2/g), it has better CO2 adsorption capacity ranging up to 4.5 mmol/g because of its well-developed pore structures and a high proportion (90 %) of micropore distributions. The isosteric heat of adsorption lower than 40 kJ/mol indicated that adsorption is mainly driven by physisorption. Better CO2/N2 selectivity suggested a high affinity of the activated carbons towards CO2. Particularly, the sample activated with KOH had selectivity in the range of 20 at the highest adsorption temperature (40 °C), making it a potentially viable option for direct CO2 adsorption applications from large industrial sources.

The study evaluated the impact of lemon peel fermented with Lactobacillus plantarum (FLP) being a practical feed additive, and its effects on growth performance, non-specific immune indicators, and disease resistance for whiteleg shrimp (Litopenaeus vannamei). The FLP was incorporated into the control diet at a graded level of 0%, 1%, 2%, and 3%. Four experimental feeds were randomly assigned to 4 replicates of L. vannamei with average weight of 2.37 g in a recirculation system for 56 days. Shrimp fed the four diets revealed similar (p > 0.05) weight gain percentage (489.01%−520.25%), feed conversion rate (2.46–2.70), protein efficiency ratio (1.05–1.14), and survival (78.75%−90.00%) after the feeding trial. Total hemocyte count (THC) was higher in shrimp delivered feeds containing 1% and 2% FLP whereas the phenoloxidase (PO) activity was advanced in shrimp fed the feed containing 2% FLP comparing with the FLP-free control group. In the V. alginolyticus challenge test, final survival after 72 h injection was higher in shrimp delivered feeds containing 2% and 3% FLP (66.67%−70.00%) than that in the control group (43.33%). The findings emphasize that fermented lemon peel is a potential functional feed additive on improving immunity and disease resistance for whiteleg shrimp, and showing no negative effects on growth and hepatopancreas morphology. An inclusion rate of 2% FLP is suggested for whiteleg shrimp to maximize the THC and PO activity and resistance ability to V. alginolyticus.

The Food and Agricultural Organization estimates a 17% loss in the food production chain, making it imperative to adopt scientific and technological approaches to address this issue for sustainability. Industrial food production waste and its value-added applications, particularly in relation to a wide variety of pathogenic microorganisms and the health-related effects have not been thoroughly investigated. This study explores the potential of food production waste extracts—lemon peel (LP), hot trub (HT), and coffee silverskin (CSS) as sources of bioactive compounds. Extraction was conducted using hydro-methanolic extraction with yields in LP (482 mg/1 g) > HT (332 mg/1 g) > CSS (20 mg/1 g). The agar diffusion assay revealed the substantial antibacterial activity of all three extracts against Erwinia Amylovora, Escherichia coli, Bacillus subtilis, and Bacillus aquimaris. All extracts demonstrated activity against Gram-positive and Gram-negative bacteria, displaying minimum inhibitory concentrations effective against pathogenic bacteria like Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella enterica. Total phenolic content (TPC in mg GAE/1g) was 100, 20, and 100 for CSS, HT, and LP, respectively. Antioxidant activity by ABTS indicated IC50 of 3.09, 13.09, and 2.61 for LP, HT, and CSS, respectively. Also, the antioxidant activity of the extracts was further confirmed by DPPH assay with the best activity in CSS (9.84 GAEg−1) and LP (9.77 mg of GAEg−1) rather than in HT (1.45 GAEg−1). No adverse cytotoxic effects on HaCaT cells were observed. Pancreatic amylase inhibition demonstrated antidiabetic potential, with LP showing the highest levels (92%). LC-MS characterization identified polyphenols as the main compounds in CSS, prenylated compounds in HT, and flavanols in LP. The findings imply the potential sustainable use of food production waste in industry.

The urgent need for efficient decontamination of organic dyes from polluted waters necessitates the search for a low-cost and suitable adsorbent. The large amount of lemon peel residue in actual production can be an ideal raw material for the preparation of adsorbents. Herein, a novel magnetic nanocomposite derived from lemon (Citrus limon L.) peel residue (Fe3O4/Lp-biochar) was successfully synthesized by one-step hydrothermal method and used for the adsorptive capture of methylene blue (MB) in aqueous solution. The prepared Fe3O4/Lp-biochar are spherical with a particle size of 8.3 nm and have a saturation magnetization intensity of 52.9 emu/g and a specific surface area of 64.30 m2/g. It was found that the maximum MB adsorption capacity of 26.36 mg/g by the Fe3O4/Lp-biochar can be achieved when the amount of nanocomposite was 0.10 mg/mL, the system's pH value was 10, the reaction temperature was 25 °C, and the adsorption time was 60 min. Adsorption kinetics of MB on the Fe3O4/Lp-biochar followed the pseudo-second-order kinetic model whilst the Freundlich isotherm model could well simulate the adsorption behavior of MB on magnetic biochar. The adsorption mechanism of MB by the Fe3O4/Lp-biochar predominantly include electrostatic attraction and mesoporous interaction. Furthermore, the Fe3O4/Lp-biochar exhibited a remarkable retention of 94.7% of the initial adsorption efficiency even after the 10th cycle of repeated use. It was concluded that the lemon peel-derived magnetic biochar can be a promising alternative to conventional adsorbents for wastewater treatment.

Lemon peel is the major by-product of lemon juice processing and is currently underutilized. In this study, we explored the feasibility of using lemon peel as a raw material for making vinegar. Lemon peel was homogenized, treated with pectinase (30,000 U/g, 0.1%) at 50 °C for 4 h, and then filtered. The obtained lemon peel juice was first subjected to alcoholic fermentation by Saccharomyces cerevisiae var. FX10, and then acetic fermentation by an acid tolerant Acetobacter malorum, OQY-1, which was isolated from the lemon peels. The juice yield of the lemon peel was 62.5%. The alcoholic fermentation yielded a lemon peel wine with an alcoholic content of 5.16%, and the acetic acid fermentation produced a vinegar with a total acid content of 5.04 g/100 mL. A total of 36 volatile compounds were identified from the lemon vinegar, with some compounds such as esters and some alcohols that increased significantly during alcoholic fermentation while alcohols, terpenoids, and some esters decreased significantly during the fermentations. E-nose and E-tongue analyses coupled with principal component and discriminant factor analyses (PCA and DFA) were able to discriminate the samples at different fermentation stages. Overall, this work demonstrates the potential to transform lemon peel into a valuable product, thus reducing the waste of lemon processing and adding value to the industry. [ABSTRACT FROM AUTHOR]

The impact of hydrogen infusion into solvents on the extraction of phytochemicals was evaluated. Pure (water, ethanol, methanol) and hydrogen-rich solvents at temperatures (25°C and 35°C) were used for extracting phenolics, flavonoids, anthocyanins, and antioxidants from lemon peel. Incorporating hydrogen into all solvents increased the extraction of all phytochemicals. The hydrogen incorporation into solvents led to the highest increase in phenolics and flavonoid contents shown for hydrogen-rich methanol (HRM) followed by hydrogen-rich ethanol (HRE) at both 25°C and 35°C. The highest antioxidant extraction was shown for HRM. The hydrogen incorporation showed the highest phytochemical extraction in methanol and at 35°C. The increase in temperature increased the extraction efficiency, but less efficiently than the hydrogen incorporation. The HPLC phenolic profile confirmed the positive effect of both temperature and hydrogen incorporation on the extraction of flavonoids and non-flavonoids. The improvement of the phytochemical extraction by the proposed method can bring many economic and ecological advantages.

Gout arthritis is a joint pain disorder characterized by swelling around joints and elevated uric acid levels. These elevated uric acid levels result in joint stiffness and pain. The elevated uric acid level is due to over activity of xanthine oxidase. Lemon peel can inhibit the activity of xanthine oxidase. In this study, twenty male albino Wistar rats with induced arthritis were enrolled and were divided into four groups; control group (Go) and treatment group G1, G2, and G3. Treatment groups were given three different levels of lemon peel 150mg, 300mg and 450 mg per kg of body weight. Serum uric acid levels were measured before and after the trial. Chemical characterization and phytochemical analysis were also performed. The presence of 9.07±1.16% moisture in lemon peel. A total of 1.71±0.13% ash was present in lemon peel while 62.45±8.09% of carbohydrates were present in lemon peel. 4.04±0.08% crude protein, 9.87±1.63% crude fat, and 12.86±0.09% crude fiber wass present in lemon peel. Lemon peel held a significant amount of TPC and TFC depicted in fig. 1. Total phenolic content (TPC) was 1204±23.02 mg GAE/100g and total flavonoid content (TFC) was 471.98±11.74 mg QE/100g. The investigation had shown a significant (p<0.05) reduction in uric levels in response to lemon peel powder in all treatment groups. ANOVA test showed a significant reduction in uric acid levels when lemon peel was given to subjects. [ABSTRACT FROM AUTHOR]

In this research, the effects of carboxymethyl cellulose (CMC) contains lemon peel and walnut shell essential oils as edible coatings on the shelf life and postharvest losses of mushrooms were studied. Mushrooms were stored at 4 °C for 12 days and physicochemical characteristics were analyzed after 0, 4, 8 and 12 days of storage. During cold storage, the uncoated mushrooms showed rapid weight loss and total soluble solid changes while mushrooms treated with CMC coating containing lemon peel and walnut shell essential oils significantly (p<0.05) delayed these phenomena. Although firmness of both coated and control samples decreased throughout storage, the use of CMC -essential oils coating significantly (p<0.05) reduced the loss of firmness in mushroom samples. The L* value changes of the mushrooms coated with CMC -essential oils was lower than that of others. A significant (p<0.05) decrease in L* value and a significant (p<0.05) increase in a and b values occurred in all mushrooms during the maintenance period. The use of edible coating led to significant (p<0.05) decrease in number of microorganisms of the mushrooms during all days of storage. Incorporation of the essential oils into CMC coating solution caused increase in microbial quality of the coated samples. Using the CMC coating containing 3% lemon peel essential oil led to significantly increasing (p<0.05) of sensory parameter scores, so that the treatment containing 3% lemon peel essential oil had the highest acceptability score compared to control and other treatments. [ABSTRACT FROM AUTHOR]

This research paper presents a study on the preparation and characterization of nano graphite materials (NGMs) from lemon and orange peel powder using the pyrolysis method. The NGMs were analyzed using X-ray Diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR) for structural and compositional properties. The XRD analysis confirmed the crystalline nature of the NGMs, while the FTIR analysis provided information about the functional groups present in the materials. Our results suggest that NGMs fabricated from lemon and orange peel powder have potential for applications in various fields, including energy storage and catalysis.

The food wastes have significant amount of functional ingredients that have valorization potential. Citrus limon (lemon), Mangifera Indica (mango) peels are maximally used as waste in food industries in all over the worlds. This work aimed to extract pectin from mango and pectin peels at different conditions, and pectin yield, degree of esterification (DE), intrinsic viscosity (η) and molecular weight (Mw) were determined. The best conditions of extraction were pH 2, temperature 80 °C, time 4 h for lemon and 5 h for mango, where pectin yields were 30.60 ± 0.95 and 31.70 ± 1.04%, respectively. At this condition, DE, η, Mw were 42.02%, 0.177 and 42,316 g/mol for lemon peel while 30.60%, 0.05 and 8364.01 g/mol for mango peel, respectively. The extracted pectin under optimal conditions was used to fabricate pectin-silica based film. All the composition of films showed considerable mechanical properties due to the presence of silica. The highest values of tensile strength and young modulus were found 61.31 MPa and 16.49 MPa, respectively, at the silica percentage of 1.25% (w/v) where toughness and elongation at break were decreased due to the more bonding between pectin and silica. This study demonstrated that incorporating silica at 1.25% (w/v) can improve the physicochemical properties of pectin film.

Lemon peel is the major by-product of lemon juice processing and is currently underutilized. In this study, we explored the feasibility of using lemon peel as a raw material for making vinegar. Lemon peel was homogenized, treated with pectinase (30,000 U/g, 0.1%) at 50 °C for 4 h, and then filtered. The obtained lemon peel juice was first subjected to alcoholic fermentation by Saccharomyces cerevisiae var. FX10, and then acetic fermentation by an acid tolerant Acetobacter malorum, OQY-1, which was isolated from the lemon peels. The juice yield of the lemon peel was 62.5%. The alcoholic fermentation yielded a lemon peel wine with an alcoholic content of 5.16%, and the acetic acid fermentation produced a vinegar with a total acid content of 5.04 g/100 mL. A total of 36 volatile compounds were identified from the lemon vinegar, with some compounds such as esters and some alcohols that increased significantly during alcoholic fermentation while alcohols, terpenoids, and some esters decreased significantly during the fermentations. E-nose and E-tongue analyses coupled with principal component and discriminant factor analyses (PCA and DFA) were able to discriminate the samples at different fermentation stages. Overall, this work demonstrates the potential to transform lemon peel into a valuable product, thus reducing the waste of lemon processing and adding value to the industry.

Jun Wang,1,2 Yulin Zhai,1 Mingguang Ou,3 Yunfeng Bian,4 Chenglong Tang,5 Wanchao Zhang,6– 8 Yujiao Cheng,1,2 Guijie Li1,2 1Citrus Research Institute, Southwest University, Chongqing, People’s Republic of China; 2National Citrus Engineering Research Center, Chongqing, People’s Republic of China; 3Guang’an Nongfeng Agricultural Development Co., Ltd, Sichuan, People’s Republic of China; 4Guang’an Zheng Wang Agriculture Co., Ltd, Sichuan, People’s Republic of China; 5Yuanyang Hongtu Grapefruit Agricultural Technology Development Co., Ltd, Yunnan, People’s Republic of China; 6Chongqing Institute of Medicinal Plant Cultivation, Chongqing, People’s Republic of China; 7National Patent Navigation Project (Chongqing) Research and Promotion Center, Chongqing, People’s Republic of China; 8Bio-Resource Research and Utilization Joint Key Laboratory of Sichuan and Chongqing, Chongqing, People’s Republic of ChinaCorrespondence: Wanchao Zhang Tel +86-13072382527Email boystory@163.comGuijie Li 15# Ganjucun, Xiema, Beibei District, Chongqing, 400712, People’s Republic of ChinaTel +86-17388209637Email liguijie@cric.cnAim: Lemon peel, a traditional Chinese medicine, was tested in this study for its novel application in inhibiting cellular oxidative stress, and the effect of lemon peel extract (LPE) on protecting H9c2 rat heart cells from oxidative stress was investigated.Methods: The scavenging effects of LPE on 1,1-diphenyl-2-picryhydrazyl (DPPH) and 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) free radicals were measured in extracellular experiments. The 3-(4,5-dimethyl-2-thiazolinyl)-2,5-diphenyl-2-h-tetrazolylammonium bromide (MTT) assay was used to detect the cell survival rate. The cell supernatant and intracellular oxidation-related indicators were detected by a kit, and the mRNA expression in H9c2 cells was detected by quantitative polymerase chain reaction (qPCR). The chemical substances of LPE were analyzed by high-performance liquid chromatography (HPLC).Results: The results showed that LPE exhibited better DPPH and ABTS free radical scavenging abilities than vitamin C. Compared with the cells in the normal state (control group), the cell survival rate in the model group decreased, and the level of lactate dehydrogenase (LDH) increased, the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) decreased, and the content of malondialdehyde (MDA) increased. Compared with the control group, the expression of Bcl-2-related X protein (Bax), caspase-3, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) in the model group was increased, and the expression of B-cell lymphoma-2 (Bcl-2) was reduced. Compared with the model group, LPE treatment improved the cell survival rate, reduced the levels of LDH and MDA, increased the levels of SOD, CAT, and GSH, downregulated the expression of Bax, caspase-3, Nrf2 and HO-1, and upregulated the expression of Bcl-2. The composition analysis showed that LPE contained catechin, rutin, naringin, quercetin, and hesperidin.Conclusion: The results indicated that LPE could protect H9c2 cells from oxidative stress through five active components. LPE has the potential to be developed into natural medicine or health food for the inhibition of cell oxidative damage.Keywords: lemon peel, oxidative stress, H9c2 rat heart cell, mRNA expression, HPLC

Synthetic dyes from different sources (wastewater and effluents) can be harmful to the environment even at minor quantity. Low cost natural biosorbent have been proved beneficial for water treatment and have excellent capability for the elimination of certain dyes from aqueous media. The present study purposed to utilize lemon peel as a natural sorbent for eosin dye in an aqueous media. The biosorbent were analyzed utilizing fourier transform infrared spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray analysis (EDX) and surface area analyzer (BET). The batch adsorption approach was carried out to optimize the basic parameters affecting the sorption phenomena. Anionic dye, eosin, was removed by adsorption utilizing lemon peel, as an biosorbent and such adsorption are affected by different physical factors i.e adsorbent dose, contact time, temperature etc. Freundlich and Langmuir's adsorption isotherm models are used to verify the results. The monolayer adsorption capacity was 8.240 mg/g at 30 °C that is calculated from Langmuir isotherm. The adsorption process is exothermic, shown by calculations thermodynamic parameters. Kinetics studies have represented that the adsorption process could be better explained by pseudo-second-order kinetics. All the parameters of biosorbent were compared with each other and proved that lemon peel, which is readily available, economic biosorbent, for the removal of eosin dye from the aqueous media.

Copyright of Journal of Food & Dairy Sciences is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simultaneous adsorption of heavy metals in complex multi metal system is insufficiently explored. This research gives results of key process parameters optimization for simultaneous removal of Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution (batch system). New lemon peel-based biomaterial was prepared and characterized by infrared spectroscopy with Fourier transformation (FTIR), scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS), while the quantification of metals was made by atomic absorption spectrometry (AAS). Simultaneous removal of seven metals ions was favorable at pH 5 with 300 mg/50 mL solid-liquid phase ratio, within 60 min at room temperature with total obtained adsorption capacity of 46.77 mg g−1. Kinetic modeling showed that pseudo-second order kinetic and Weber-Morris diffusion models best describe the adsorption mechanism of all seven heavy metals onto lemon peel.

The one-third of all food produced for human use is wasted each year which has made food waste a serious problem all around the world. Citrus juice manufacturing factories generate peel leftovers that can account for 50-60% of the weight of the fruit, contributing significantly to food waste. This study investigates the extraction of orange and lemon peel oils using the Soxhlet process and their analysis via gas chromatography. The aim is to identify and quantify key volatile compounds present in these oils, thereby putting the leftover peels to use. Fresh orange and lemon peels were transformed into zest and extracted using Hexane and Ethanol as solvent in a Soxhlet apparatus. Gas chromatography with a specialized column and detector unveiled major volatile compounds, including limonene, linalool, citral. These compounds contribute to the characteristic aroma and potential bioactivity of the oils. Orange peels displayed notably higher limonene content compared to lemon peels. This approach illuminated the chemical composition of the oils, offering opportunities in food, cosmetics, and fragrance industries. Orange peels contained 70-90% limonene, significantly more than lemon peels. The study concluded that peels harbor 28 volatile substances, with limonene responsible for their distinctive citrus scent. In sum, this research underscores the effectiveness of Soxhlet extraction, providing insights into orange and lemon peel oils’ composition using Gas chromatography and applications.

The main purpose of the agriculture circular economy is waste recycling with the intended goal of economic efficiency and environmental protection. In this study, the potential use of lemon peel, an agricultural waste, as a functional feed additive in aquafeed was evaluated by estimating the effects of fermented lemon peel (FLP) supplementation in diet on the growth, immune responses, and intestinal morphology of Asian sea bass, Lates calcarifer. Lemon peel was fermented by Lactobacillus plantarum. Basal diet was supplemented with 0%, 1%, 3%, and 5% FLP. Four experimental diets were each fed in triplicate to juvenile Asian sea bass (initial weight: 11.42 ± 0.39 g) in a recirculation rearing system for 8 weeks. Final weight, weight gain, feed intake, and survival were similar (p > 0.05) among all dietary treatments. Plasma lysozyme activity was higher in fish fed the diet with 3% FLP than that in fish fed the diet with 5% FLP. Hepatic thiobarbituric acid-reactive substance values were lower in fish fed diets with ≤3% FLP than that in fish fed the diet with 5% FLP. Fish fed diets with 1% and 3% FLP showed a tight lamina propria (LP) in microvilli compared with fish fed diets with 0% and 5% FLP. The microvilli area/height ratio was higher in fish fed diets with 0% and 5% FLP than that in fish fed diets with 1% and 3% FLP. The minimum level obtained from the second-order polynomial regression model were 0.26 % for microvilli area and area/height ratio. Results indicate that diets supplemented with 1 %–3 % fermented lemon peel can improve intestinal health for Asian sea bass. However, 5% FLP supplementation may lead to low immune response and high oxidative stress.

Considering the environmental and energy concerns, the need for finding an alternative fuel is increasing greatly. But also, the toil associated with finding the suitable fuel for the engine under study is very high. As a measure to reduce this work, theoretical analysis can be used in the search of suitable fuel blends. The present study deals with the creation of an Artificial Neural network (ANN), training, testing the network and finally comparing the predicted values with the experimental values. The test engine was operated with lemon peel oil, with different ratios of Di tertiary butyl peroxide (DTBP), rice husk nanoparticles and water injection. Six engine output parameters (BTE, BSFC, HC, NOx, CO & Smoke) were predicted for different input values of engine load, DTBP proportions, RH nanoparticle concentration and water injection percentage. A single cylinder constant speed direct injection diesel engine is used for obtaining all the experimental values. From the obtained results a data set of 70 experimental values were used to train and test the neural network formed. The predicted values were correlated with the experimental values and the R2 was found for each correlation. The R2 values, thus obtained is in the range of 0.98209 to 0.99744 (which is very close to unity) thus proving that the network created were able to predict the performance and emissions of engine accurately. This work shows the prediction of multi component fuel mixture using ANN, which is new and also helps to reduce the experimental works needed to find the engine output parameters.

Objective: The importance of oral care has recently been suggested based on the role of periodontal disease bacteria in the pathogenesis of arteriosclerotic disease and diabetes, the relationship between chewing power and brain function, and the relationship between saliva and healthy life expectancy. In the present study, the effects of domestic lemon peel on saliva secretion and oral bacterial counts were measured to investigate its potential use in oral care. Materials and Methods: The subjects enrolled in the present study were 36 community-dwelling healthy elderly individuals aged 60 years or older (age: 70.0 ± 5.9 years old). The duration of the intervention period was set at 2 weeks and a survey with a single ingestion was conducted before and after the intervention. Subjects were divided into water (11 subjects (control)), lemon juice (11), and lemon peel (12) groups. Measurement items are saliva secretion and measurement of viable bacterial counts in saliva. The Kruskal-Wallis test was used to analyze differences among the intervention beverages (inter-individual levels among the water, lemon juice, and lemon peel groups) as a factor and saliva secretion and bacterial counts in saliva as response variables. The Bonferroni test was used for multiple comparisons. Results: Changes in saliva secretion and viable bacterial counts in saliva after sample ingestion were investigated. An immediate increase in saliva secretion was observed after the ingestion of samples containing lemon peel, but not after the ingestion of water. Furthermore, slight decreases were noted in oral bacterial counts. Conclusion: An increase in saliva secretion may be useful in oral care not only for the maintenance and protection of the intraoral environment, but also physical function and QOL. [ABSTRACT FROM AUTHOR]

The role of dietary lemon peel (LM) and/or Bacillus licheniformis (BL) on the growth, immunity, and resistance against Aeromonas hydrophila in common carp, Cyprinus carpio was investigated in this study. LM and BL were included in diets at 0% (T0), 108 CFU/g BL (T1), 1.5% LM and 108 CFU/g BL (T2), and 3% LM and 108 CFU/g BL (T3). Fish fed with T1, T2, or T3 had higher weight gain, specific growth rate, white blood cells count, and blood total protein with lower feed conversion ratio than T0 group (p <.05). The albumin increased significantly (p <.05) in fish fed both BL and LM (T3). The serum superoxide dismutase (SOD), catalase, lysozyme, and bactericidal activities were significantly increased in fish fed both BL and LM (T2 and T3), while serum glutathione peroxidase increased in fish fed BL (T2) (p <.05). Fish fed T1, T2, and T3 diets displayed higher SOD and lower malondialdehyde than fish fed T0 (p <.05). After the A. hydrophila challenge, the mortality rate was significantly lower in T1, T2, and T3 groups than the T0 group (p <.05). The obtained results revealed that LM and BL could be used to increase resistance against A. hydrophila infection in carp. However, further field studies should be performed to confirm the obtained results. [ABSTRACT FROM AUTHOR]

The citrus juice industry produces a significant amount of peel residues; it can represent between 18 and 30% of the total weight of the fruit. In recent years, there has been an increase in its use as a source of fiber. The objective of this study was to evaluate the Tahiti lemon peel flour (Citrus latifolia Tanaka) as a fat mimetic (10, 20 and 30%) in a cake. The chemical and nutritional characterization of the lemon peel, the determination of the drying conditions to obtain the flour of the lemon peel, and the physical, chemical, and nutritional characterization of the lemon peel flour and cake was evaluated. A high content of dietary fiber for Tahiti lemon peel (89.15 ± 0.00 g/100 g) and flour (85.30 ± 0.06 g/100 g) was obtained. For the drying conditions to obtain the lemon peel flour, a temperature of 60 °C during 16 h was selected. The cake with greater acceptability had a 10% fat replacement with lemon peel flour, which presented a reduction of 19.16% in the fat content and an approximately double increase in the dietary fiber content. This study suggests that the flour obtained from Tahiti lemon flavedo can be used as a mimetic of fat in cakes, contributing to the nutritional characteristics of the food in which it is included. [ABSTRACT FROM AUTHOR]

Lemon peel can be used as traditional Chinese medicine. Flavonoids are the most important components in lemon peel, which can be developed as natural medicine without side effects. This study investigated the protective effect of lemon peel polyphenols (LPP) on human keratinocyte HaCaT cells under oxidative stress. The active components of LPP were determined by high performance liquid chromatography. The abilities of LPP to scavenge DPPH and ABTS+ free radicals were studied for detection of antioxidation in vitro. Cell survival rates were determined by MTT assay. The antioxidant enzyme activity and antioxidant index of cells were determined using kit. The mRNA and protein expression of cells were determined by qPCR and western blot. The ability of LPP to scavenge DPPH and ABTS+ free radicals were stronger than those of vitamin C (Vc) at the same concentration. As expected, compared with the normal group of cells, the model group had decreased cell survival, increased lactate dehydrogenase (LDH), decreased levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH), and increased malondialdehyde (MDA) content. qPCR and western blot results indicated that the expression of Bcl-2-related X protein (Bax), caspases-3, erythroid-derived nuclear factor 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were decreased and the expression of B-cell lymphoma-2 (Bcl-2) was increased in the model group, compared with the normal group. LPP treatment improved cell survival rate, reduced intracellular LDH and MDA levels, increased intracellular SOD, CAT, GSH levels, down-regulated Bax, caspases-3, Nrf2, HO-1 expression, and up-regulated Bcl-2 expression. Component analyses found that LPP contains gallic acid, neochlorogenic acid, (+)-catechin, caffeic acid, (−)-Catechin gallate, isochlorogenic acid A, rosmarinic acid, and protocatechuic acid. LPP was found to regulate the Nrf2/HO-1 signaling pathway through 8 active substances to protect HaCaT cells against oxidative stress in vitro.

Lemon peel powder (LPP) obtained after drying (microwave, infrared, and oven) showed the lowest (58.72%) DPPH-radical scavenging activity in oven-dried and the highest (67.84%) in infrared-dried LPP while that of fresh lemon peel remained 63.22%. Orange peel powder (OPP) showed the lowest DSA (61.65) after microwave and the lowest (63.54%) after infrared-drying while that of fresh orange peel was 63.48%. Total phenolics were between 114.58 (fresh) and 179.69 mgGAE/100 g (oven) in LPP and between 158.54 (fresh) and 177.92 mgGAE/100 g (infrared) in OPP. The total flavonoid contents were 380.44 (fresh)–1043.04 mg/100 g (oven) in case of LPP and 296.38 (fresh)–850.54 mg/100 g (oven) in case of OPP. The gallic acid contents were 2.39 (fresh)–14.02 mg/100 g (oven) in LPP. The (+)-catechin contents were 1.10 (fresh)–49.57 mg/100 g (oven) for LPP and 0.82 (fresh)–7.63 mg/100 g (infrared) in case of OPP. The oleic acid content was 22.99 (infrared)–58.85% (fresh) in LPP-oil and 28.59 (microwave)–61.65% (fresh) in OPP-oil. The linoleic acid contents were 13.76 (fresh)–36.90% (oven) in LPP-oil and 14.14 (fresh)–37.08% (infrared) in case of OPP-oil. The drying techniques showed profound but variable effects on radical scavenging activity, total phenolics, flavonoid, carotenoids, phenolic compounds and fatty acid composition of both LPP and OPP and oven-drying (60 °C) was the most effective in improving these bioactive constituents. [ABSTRACT FROM AUTHOR]

In this study, lemon peel flavonoids (LPF) were administered to investigate its effect on the anti-fatigue and antioxidant capacity of mice that undergo exercise until exhaustion. LPF (88.36 min in LPFH group mice) significantly increased the exhaustion swimming time compare to the untreated mice (40.36 min), increased the liver glycogen and free fatty acid content in mice and reduce lactic acid and BUN content in a dose-dependent manner. As the concentration of lemon peel flavonoids increased, the serum creatine kinase, aspartate aminotransferase, and alanine aminotransferase levels of mice gradually decreased. LPF increases superoxide dismutase (SOD) and catalase (CAT) levels in mice and reduces malondialdehyde levels in a dose-dependent manner. And LPF raises hepatic tissue SOD, CAT activities and reduces skeletal muscle tissue iNOS, TNF-α levels of mice compared to the control group. LPF also enhanced the expression of copper/zinc-superoxide dismutase (Cu/Zn-SOD), manganese-superoxide dismutase (Mn-SOD), and CAT mRNA in mouse liver tissue. LPF also enhanced the expression of alanine/serine/cysteine/threonine transporter 1 (ASCT1) mRNA and attenuate the expression of syncytin-1, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α in mouse skeletal muscle. According to high-performance liquid chromatography (HPLC) analysis, it was found that LPF contains flavonoids such as rutin, astragalin, isomangiferin, naringin, and quercetin. Our experimental data show that LPF has good anti-fatigue effects and anti-oxidation ability. In summary, LPF has high prospects to be developed and added to nutritional supplements. [ABSTRACT FROM AUTHOR]

This study examines the ameliorative effects of lemon (Citrus limon) peel (LP) powder on intestinal inflammation and barrier defects in dextran sulfate sodium (DSS)-induced colitic mice. The whole LP powder was fractionated into methanol (MetOH) extract and its extraction residue (MetOH residue), which were rich in polyphenolic compounds and dietary fibers, respectively. Mice were fed diets containing whole LP powder, MetOH extract, and MetOH residue for 16 d. DSS administration for 9 d induced bodyweight loss, reduced colon length, reduced the colonic expression of tight junction proteins including zonula occludens-1 and -2, and claudin-3 and -7, and upregulated colonic mRNA expression of interleukin 6, chemokine (C-X-C motif) ligand 2, and C-C motif chemokine ligand 2. Feeding LP powder restored these abnormalities, and the MetOH residue, but not MetOH extract, also showed similar restorations. Feeding LP powder and MetOH residue increased fecal concentrations of acetate and n-butyrate. Taken together, LP powder reduced intestinal damage through the protection of tight junction barriers and suppressed an inflammatory reaction in colitic mice. These results suggest that acetate and n-butyrate produced from the microbial metabolism of dietary fibers in LP powder contributed to reducing colitis.

The urgent need for efficient decontamination of organic dyes from polluted waters necessitates the search for a low-cost and suitable adsorbent. The large amount of lemon peel residue in actual production can be an ideal raw material for the preparation of adsorbents. Herein, a novel magnetic nanocomposite derived from lemon (Citrus limon L.) peel residue (Fe 3 O 4 /Lp-biochar) was successfully synthesized by one-step hydrothermal method and used for the adsorptive capture of methylene blue (MB) in aqueous solution. The prepared Fe 3 O 4 /Lp-biochar are spherical with a particle size of 8.3 nm and have a saturation magnetization intensity of 52.9 emu/g and a specific surface area of 64.30 m2/g. It was found that the maximum MB adsorption capacity of 26.36 mg/g by the Fe 3 O 4 /Lp-biochar can be achieved when the amount of nanocomposite was 0.10 mg/mL, the system's pH value was 10, the reaction temperature was 25 °C, and the adsorption time was 60 min. Adsorption kinetics of MB on the Fe 3 O 4 /Lp-biochar followed the pseudo-second-order kinetic model whilst the Freundlich isotherm model could well simulate the adsorption behavior of MB on magnetic biochar. The adsorption mechanism of MB by the Fe 3 O 4 /Lp-biochar predominantly include electrostatic attraction and mesoporous interaction. Furthermore, the Fe 3 O 4 /Lp-biochar exhibited a remarkable retention of 94.7% of the initial adsorption efficiency even after the 10th cycle of repeated use. It was concluded that the lemon peel-derived magnetic biochar can be a promising alternative to conventional adsorbents for wastewater treatment. [ABSTRACT FROM AUTHOR]

Pb(II) adsorption from the water using adsorbents such as acid and/or base activated walnut shell and lemon peel was carried out in a continuous stirring batch system. The original and activated adsorbents were characterized by SEMEDS and FTIR analyses. SEM photographs of both adsorbents showed that while the presence of irregularly shaped and layered structures were observed before activation, more porous and curved surfaces were observed after activation. Adsorption studies showed that the activation was effective for increasing the adsorption efficiency and while more than 5 0% of the lead ions were removed at the first 10 min, the equilibrium was reached at 180 min. Furthermore, they showed that the adsorption rate was determined by a pseudo second order kinetic model. Additionally, Freundlich and Langmuir isotherm models were investigated for Pb(II) adsorption on WS-NaOH and LP-HNO3 adsorbents and it was found that the equilibrium data were more suitable for Freundlich model. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of material type (artichoke leave, lemon peel, flaxseed meal), extraction temperature (50, 100, 120, 140, 160, 180, 200 °C) and static extraction time (5, 15, 30, 45 min) on 5-hydroxymethylfurfural (5-HMF) formation during subcritical water extraction. 5-HMF content of artichoke leave and lemon peel extracts increased 7.2 and 26.1 times with the rise of extraction temperature from 160 to 180 °C for 5 min during subcritical water extraction, respectively. Besides, 5-HMF content of artichoke leave, lemon peel and flaxseed meal extracts increased 1.4, 2.0 and 4.5 times as static extraction time increased from 15 to 45 min at 180 °C during subcritical water extraction, respectively. The highest 5-HMF content of artichoke leave and lemon peel extracts were obtained as 58.83 and 231.21 mg/L at 180 °C and 45 min, respectively. However, for flaxseed meal, the highest 5-HMF content (222.94 mg/L) was obtained at 200 °C and 15 min during subcritical water extraction. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of the hydroalcohol extract of lemon peel (LP) on a rat model of type 2 diabetes (T2D). Method: The rat model of T2D by injection of streptozotocin was established. The effects of a hydroalcoholic extract of LP was characterised on a rat model of type 2 diabetes based on body weight, food intake, fasting blood glucose (FBG), glucose tolerance test, and insulin tolerance test. Antioxidant activity and oxidative stress were analysed by superoxide dismutase (SOD) and malonaldehyde (MDA) assays. Results: In acute toxicity studies, administration of LP extract at 2000 mg/kg orally did not cause any symptoms of poisoning or death after 14 days. The body weight of rats increased after treatment with LP extracts. Food intake in diabetic rats decreased with LP extract treatment. Continual treatment with LP extracts for 35 days significantly reduced blood glucose levels in diabetic rats. Glucose tolerance improved, and insulin resistance was reduced after treatment with LP extracts. SOD and MDA data indicate that treatment with LP extract alleviated the oxidative stress in diabetic rats as well as enhanced the antioxidant activity of liver in a dosage-dependent manner. Conclusion: LP extract decreased food intake and FBG, but increased body weight in rats. The effect of LP on T2D is likely related to improved antioxidant activity and reduced oxidative stress. Thus, LP extract has potentials for the treatment of T2D. [ABSTRACT FROM AUTHOR]

Microwave assisted extraction treatments showed the higher pectin yields of 10.07% and 8.83% in pretreated samples by microwave and 9.4% and 8% in the extraction of dried after microwave treatment in lemon peel and apple pomace samples, respectively. Lemon peel pectin in pretreated samples by microwave and extraction of dried after microwave treatment showed the higher degree of esterification 71.8% and 70%, respectively, while apple pomace revealed 68% and 65.4% in same treatments. Furthermore, lemon peel pectin exhibited the highest galacturonic content of 74.5% in extraction of pretreated samples by microwave, while apple pomace pectin indicated the higher galacturonic acid content of 70.5% and 70% in both extraction of dried after microwave treatment and extraction of dried samples. Texture analysis of jellies prepared by various extracted pectin indicated the highest fracturability in the microwave-assisted drying treatment of 33 N and 32.5 N for apple pomace and lemon peel pectin, respectively. [ABSTRACT FROM AUTHOR]

In the present study, a high-surface area activated carbon was prepared by chemical activation of lemon peel with H3PO4 as the active agent. Then, the adsorption behavior of Malachite green dye and Pb(II) ions on the produced activated carbon was studied. Batch process was employed for sorption kinetics and equilibrium studies. Experimental data were �tted to various isotherm models. According to the Langmuir model, the maximum adsorption capacities of Malachite green dye and Pb(II) ions were found to be 66.67 and 90.91 mg g-1, respectively, at room temperature. Kinetic studies showed the adsorption process followed a pseudo second-order rate model. The sorption kinetics were controlled by intra-particle diffusion. The results indicated that the produced activated carbon can be economically and effectively used as an adsorbent for the removal of Malachite green dye and Pb(II) ions from wastewaters.