Extraction of Essential Oil Form Sweet Lime Orange Peel: A Comparison Study

This research work was designed to extract essential oil from sweet lime peel (solid waste). The feed material selected for study is sweet lime peel. The disposal of waste product such as peels often has a legal restriction problem and treatment process involved requires higher costs. Transformation of this waste in to useful products could cut global treatment costs. Hence the objective of our experimental work was to convert sweet lime peel in to essential oil which is in huge demand in food, pharma and cosmetic industry. In our experimental work eextraction of essential oil was evaluated and comparison study was made between steam distillation, hydro-distillation, solvent extraction and hydro-steam distillation. Maximum extraction yield of 2.4 % was achieved at 90 min of contact by hydro-distillation. Hydro-distillation method offers advantages in comparison with other three methods in terms of energy saving, cleanliness and reduced waste water. Chemical constituents of essential oil samples were evaluated in terms of qualitative and quantitative analyses by gas chromatography/mass spectrometry and physical techniques. The chemical profile includes thirty two components which were identified in the extracts by Gas chromatography-Mass spectroscopy (GC-MS) analysis. The dominant component identified was limonene (65 .2 to 72.8%).

Extraction and Isolation of Phenolic compounds from Sweet lime and Evaluation of Anticancer potentiality followed by Molecular docking against Topoisomerase II

The main aim and objective of the present research work was the isolation of some novel bioflavanoids from methanolic extract of peels of sweet lime (MEE-PSWL) and evaluation of in vitro anticancer activity followed by molecular docking against target protein topoisomerase II. The extraction was done by reflux condensation method and preliminary phytochemical screening of MEE-PSWL was carried out for the evaluation of bioactive molecules, the bioflavanoids present in MEE-PSWL was confirmed by spectral analysis such as ESI-MS-MS and FTIR. Molecular docking of isolated compounds was carried out against target protein Topoisomerase II with PDB id 1ZXM by Auto dock program and the best dock pose was selected based on the interaction study analysis. In vitro anticancer activity MEE-PSWL was evaluated by SRB assay toward human colon adenocarcinoma cell line SW620 and the test was carried out at different concentrations. A preliminary screening displayed that the MEE-PSWL was able to inhibit the proliferation of more than 60% of human colon adenocarcinoma SW620 cells. The maximum growth of inhibition was found to be at 125µg/ml (IC50 4.5µg/ml) and the standard drug doxorubicin was found to inhibit the maximum proliferation at concentration 75µg/ml (IC50 3µg/ml).

Aromatic compounds secreted by plants of the genus Citrus L. in greenhouse conditions

Using the GC/MS method analysis of the chemical composition of aromatic volatile compounds released by the leaves of tropical representatives of the genus Citrus L. (sweet lime (limetta) - Citrus limetta Risso and its varieties: Citrus limetta ‘Marokko', Citrus limetta ‘Kislaya oranzhevaya', sour lime - Citrus aurantiifolia ‘Taiti' and Citrus aurantiifolia ‘Foro', as well as lemon - Citrus limon ‘Beskolyuchii') in greenhouse conditions were studied. The number of aromatic substances of the gas phase of natural essential oils of leaves revealed for each of them was 38, 41, 37, 44, 37 and 30 compounds, respectively. 10 components were characteristic of all six taxa under study, which confirm their genetic affinity: D-limonene, Z-citral (neral), E-citral (geranial), elemene isomer, α-copaene, trans-α-bergamotene, benzoic acid, 3-hexenyl ester, trans-γ-bisabolene, β-caryophyllene oxide, a-humulene epoxide II. For hybrids and varieties of sweet lime (limetta) and sour lime, 7 more components belonging to the class of terpenoids are also characteristic: oxygen-containing compounds (citronellal, citronellol, citronellyl, β-sinensal) and sesquiterpenes (cadina-3.5-diene, β-caryophyllene, trans-β-bergamotene), as well as a number of individual aromatic substances, characteristic for each of the varieties in the bouquet of their citrus-coniferous aroma of leaves. The studied taxa can be recommended as part of compositions of aromatic plants in interiors for various functional purposes.

Green synthesis strategy for producing doped and undoped ZnO nanoparticles: their photocatalytic studies for industrial dye degradation

Facile and green method for synthesizing Zinc Oxide nanoparticles (ZnO NPs) was successfully carried out using unutilized sweet lime i.e., Citrus Limetta rind pulp (U-CLRP) extract. The structural, morphological and optical studies were elucidated to confirm the crystallinity, size, shape of the synthesized NPs. Copper doping on ZnO NPs (CZnO NPs) was carried out to enhance the optical properties. The as prepared and doped nanoparticle's potential for efficient degradation of a commercial dye, Methylene Blue (MB) was tested under Ultraviolet (UV) and visible light radiation. ZnO NPs showed promising results for dye degradation while improved result was witnessed for CZnO NPs. ZnO NPs showed 74% of degradation of MB dye under UV irradiation and 57% degradation under visible light radiation. CZnO NPs presented 85 and 90% degradation in the UV and visible radiation, respectively. This green reduction method utilizing biological waste sources shows a promising path for photocatalysts to be developed economically as well as efficiently in the future. These CZnO/ ZnO NPs proved their potential for embedding them as efficient catalysts for wastewater treatment plants of textile industries.

Inhibitory and complementary therapeutic effect of sweet lime (Citrus limetta) against RNA-viruses

Sweet lime (), known as 'Mousambi' or 'Mosambi' in India, is one of the best citrus fruits regarding its nutrient contents. Its bioactive compounds (BAC) are exclusively used for multiple clinical applications considering many therapeutic benefits not only in Asian countries but also in the western world. The fruit pulp and juice are the best sources of ascorbic acid, B-vitamins, amino acids, and other secondary metabolites. Specifically, polyphenols such as flavanones, hesperetin, naringenin, and chlorogenic acid are highly rich in the fruit. The nutrients in sweet lime altogether provide significant anti-inflammatory, antioxidant, anti-cancer, and neuroprotective effects. The purpose of this study is to review and analyze the inhibitory and complementary therapeutic effects of sweet lime's pulp and juices to inhibit the virulence caused by RNA viruses, mainly SARS-CoV-2. This review study was designed based on extensive online searches of relevant open-access literature available in the best quality and reliable databases by using specific keywords and boolean operators. After a rigorous review, we found that flavanones in the fruit can alter or inhibit the polyproteins (pp1a and pp1b) responsible for viral replication. Therefore, sweet lime has potentialities to provide an inhibitory and a complementary therapeutic effect against RNA viruses, mainly SARS-CoV-2. About the antiviral activities, more clinical trials are needed to prove its efficacy; however, reviewing current knowledge, is one of the potent antioxidant, inflammatory fruits available and affordable almost worldwide.

Green synthesis of copper oxide nanoparticles using Citrus limetta (sweet lime) peel waste

The fast development of nanomaterials in the quest for green, eco-friendly routes for new products often culminates in the utilization plant biomasses for the synthesis of sustainable nanoparticles. In this study, an eco-friendly, and cost-effective method has been established for the synthesis of copper oxide nanoparticles (CuONPs) using sweet lime peel extract. The synthesized nanoparticles were characterized using UV-visible spectroscopy and scanning electron microscopy. The CuONPs formed were almost agglomerated spherical in shape with a discrete rough appearance. The particle sizes measured from scanning electron microscopy (SEM) ranged from 90-175 nm. The results revealed the cost effective, time saving, renewable, green and sustainable route for CuONPs to be formed. This may open a new avenue of methods to reuse sweet lime peels.

Active Biodegradable Films Based on Sweet Lime Peel Residue and Its Effect on Quality of Fish Fillets

Residual sweet lime peels after the extraction of essential oil by solvent free microwave extraction were used for developing biodegradable film. Glycerol as a plasticizer, soya lecithin as an emulsifier and sweet lime essential oil (0, 1, 2 and 3%) as an active agent was employed. Developed films were analyzed for their mechanical, barrier and antimicrobial properties. The films (with 3% essential oil) which reported highest antimicrobial property against E. coli (24.24 ± 2.69 mm) were wrapped on fish fillet and stored at the refrigerated condition for 12 days. The quality of fish fillets was evaluated every 4 days and compared with polyethylene wrapped and control fish fillets. The active film wrapped sample showed less surface microbial count (3.28 ± 0.16 log cfu/cm2) compared to polyethylene wrapped sample. The hardness values were increased during storage and cohesiveness and springiness of all wrapped samples decreased from day 0 to day 12.

Effect of Process Parameters on Extraction of Pectin from Sweet Lime Peels

Pectin is a heterogeneous polysaccharide found in the cell wall, middle lamellae of many fruits and vegetables, and is widely used as gelling agent, emulsifier and stabilizer in food industry. In keeping the importance of pectin in the food industry, ultrasound-assisted extraction of pectin from sweet lime peel was investigated. The individual and interactive effect of solid-solvent ratio, ultrasound power intensity and sonication time on the pectin yield, equivalent weight and methoxyl content were studied and analyzed using multiple regression analysis. The maximum pectin yield (36.4 g/100 g), equivalent weight (740.3 mg) and methoxyl content (7.1%) was obtained under optimal condition (solid-solvent ratio of 1:24.3 g/ml, ultrasound power intensity of 80 W/cm2 and sonication time of 18.4 min). Significant (p < 0.05) effect of process parameters was found in all responses of pectin extracted from sweet lime peel. It was also revealed from the present study that ultrasound-assisted extraction of pectin from sweet lime peel is an efficient approach toward waste valorization and extraction of pectin with high yield and good quality attributes.