Drying diverse temperatures alters the Physico-chemical and phytochemical properties of moringa flowers

P Selvakumar

doi:10.4103/jpdtsm.jpdtsm_77_22

ORIGINAL ARTICLE

Year : 2023 | Volume : 2 | Issue : 1 | Page : 60-66

Drying diverse temperatures alters the Physico-chemical and phytochemical properties of moringa flowers

P Selvakumar
Department of Chemistry, Dhaanish Ahmed Institute of Technology, Coimbatore, Tamil Nadu, India

Date of Submission	16-Dec-2022
Date of Decision	20-Jan-2023
Date of Acceptance	19-Feb-2023
Date of Web Publication	13-Mar-2023

Correspondence Address:
P Selvakumar
Department of Chemistry, Dhaanish Ahmed Institute of Technology, Coimbatore - 641 105, Tamil Nadu
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jpdtsm.jpdtsm_77_22

Abstract

BACKGROUND: Moringa flowers are most excellent suited for both raw and lightly cooked application such as frying or simmer. Moringa flowers are a good quality foundation of vitamin A, a nutrient that can facilitate boost the immune system and guard overall vision health. Moringa oleifera contains vital nutrients such as minerals, vitamins and phytochemicals such as tannins and flavonoids.
AIMS AND OBJECTIVE: The present work aims to study the optimization and quality attributes retention in moringa flower through freeze dryer (FD) because the conventional drying process takes more time and energy which also affects the product quality and safety.
MATERIALS AND METHODS: Different solvents, such as ethanol, chloroform, hexane, acetone and ethyl acetate, were used to determine the presence of phytochemicals (alkaloids, tannins, flavonoids, steroids, terpenoids and saponins) in the moringa flower.
RESULTS: From Qualitative and quantitative screenings of moringa flower, the phytochemicals were highly present in methanol and ethanol extracts. Dried moringa flower powder was prepared by using fresh moringa flower, steam blanched for 2-5 min and then sulfated at 0.1% for 10 min. After that, the dehydration process was performed at different temperatures (45, 55 and 65°C) in an FD drier. FD dried moringa flower powder at 55°C was found maximum physicochemical properties and higher retention of phytochemical with special reference to β – carotene (55.41 mg), total antioxidant (460.18 mg), flavonoids (19.34 mg/RE), phenol (234.13 mg/GAE), vitamin C (485.09 mg).
CONCLUSION: According to the findings of this study, FD drying is one of the best drying techniques for preserving nutritional quality features while also being efficient and cost-effective for the entire food processing industry.

Keywords: Freeze dryer, Moringa flower, nutraceutical and phytochemicals

How to cite this article:
Selvakumar P. Drying diverse temperatures alters the Physico-chemical and phytochemical properties of moringa flowers. J Prev Diagn Treat Strategies Med 2023;2:60-6

How to cite this URL:
Selvakumar P. Drying diverse temperatures alters the Physico-chemical and phytochemical properties of moringa flowers. J Prev Diagn Treat Strategies Med [serial online] 2023 [cited 2023 Mar 31];2:60-6. Available from: http://www.jpdtsm.com/text.asp?2023/2/1/60/371635

Introduction

Moringa flowers are tiny, averaging two centimeters in diameter, and are establish hanging in delicate cluster from the undergrowth of the moringa tree. Each flower contain five soft, thin, and white petals that are occasionally glowing with yellow and have a relaxed quality, budding in multiple direction.^{[1],[2],[3],[4],[5]} Moringa oleifera (M. oleifera) is also known as the “tree of life” because of its crucial importance. Moringa belongs to the solitary genus from the family Moringaceae and contains 13 known species. Among them, M. oleifera is a highly exploited species. The other names used for moringa are horseradish tree, Mulangay, benzolive, drumstick tree, Sajna and kelor. It is also popularly denoted as a miracle tree“, “natural gift or “mother's best friend”. India is a leading moringa producer in the world, with a yearly production of 2.2 million tons and a productivity of 51 tons of tender pods per hectare. Tamil Nadu is the leading moringa-producing state in India, with an average production of 6.71 lakh tonnes of tender pods annually from a cultivated area.^[6],[7],[8] Moringa has been used in folk medicine to treat many diseases, including cardiac and circulatory stimulants; antitumor, antipyretic, antiepileptic, anti-inflammatory, antiulcer, antispasmodic, diuretic, antihypertensive, lowering cholesterol, antioxidant, antidiabetic, hepatoprotective, antibacterial, and antifungal properties; and antitumor, antipyretic, antiepileptic, anti-inflammatory.^{[9],[10],[11],[12]} Furthermore, evidence points to antioxidant activity as one of the main mechanisms of action underlying the medicinal properties of moringa leaf.^{[13],[14],[15],[16],[17]}

To prevent postharvest losses in the moringa, there is a need for processing, and it will meet the demand of the market throughout the year. Dehydration is a traditional method of preservation; hot air is used to dry food and plant materials. During the drying process, a higher temperature can lower the flavour, colour, heat-sensitive nutrients and bioactive compounds. The quality of the dried products can be improved by reducing the process temperature when compared to higher ones. Based on the product type, availability of dryer, cost, time and energy consumption desired drying techniques.^{[18],[19],[20],[21],[22]} The conventional drying process takes more time and energy than advanced techniques, and it also results in microbial contamination of food products due to prolonged processing time and improper handling, which will also affect the organoleptic properties and product quality in terms of mould growth during storage. Alternatives to conventional drying advanced dryers, viz., freeze-or vacuum-drying and heat pump-assisted dehumidified air drying (HPD), is used for dry heat-sensitive materials.^{[23],[24],[25]}

Moringa flowers applications

Moringa flowers are best suited for both raw and lightly cooked applications such as frying or simmering. The flowers must be soaked in water before consumption as many insects are attracted to the flowers and may still be inside the petals when harvested. The stamen and pistils should also be removed before eating. Once cleaned, the petals can be sprinkled into salads, blended into smoothies or juices, or pressed into oils. Moringa flowers can also be stir-fried into rice and noodle dishes, used as a garnish for curries, soups, and stews, fried and eaten as a snack, or incorporated into omelets, pasta, pizza, and seafood dishes.^{[26],[27],[28]} In India, Moringa flowers are frequently stir-fried into thoran, a side dish blending chile peppers, spices, and onions into a paste and using it to flavor the flowers. Besides fresh applications, Moringa flowers can be dried and steeped in hot water to make a nutritional tea. Moringa flowers pair well with spices such as garam masala, turmeric, curry powder, and cumin, aromatics such as ginger, garlic, and shallots, coconut, bell pepper, green beans, and meats such as mutton, poultry, and fish.^{[29],[30],[31]} Moringa flowers should be used immediately for the best quality and flavor and will keep for a couple of days when stored in an airtight container in the refrigerator. Dried Moringa flowers will keep up to one year when stored in an airtight container in a dark location.^{[32],[33],[34]}

Freeze drying

Because of the low temperature and lack of atmospheric air, freeze-drying preserves the natural product's constituents, allowing the powder's chemical, nutritional, and sensory properties to remain virtually unchanged, as well as having characteristics that inhibit the growth of microorganisms that could cause it to deteriorate.^{[35],[36],[37]} Freeze-drying is commonly employed to preserve M. oleifera leaves in impoverished nations that grow and prepare them, although the high and often changing temperatures during post-harvest often have negative impacts on health-promoting bioactive components of foods.^{[38],[39],[40]} Lyophilization, also known as freeze-drying (FD), is a novel technique that involves lowering and maintaining the effective product temperature below 0°C while simultaneously applying reduced pressure (usually around 600–700 Pa) to ensure that all of the product's moisture is sublimated from the solid-state to the vapour state.^{[41],[42],[43]} Due to drying at sub-zero temperatures, which causes no thermal degradation and resists the operation of degradative enzymes by reducing moisture, FD is superior to conventional drying methods in terms of retaining active components of produce.^{[44],[45],[46]} Generally, moringa leaves are more focused than moringa flowers because of its high nutritional benefits and availability but the research on moringa flowers are unexplored. The present study aims to optimize the freeze-drying parameters of moringa flower powder.^{[47],[48],[49]}

Materials and Methods

Physico-chemical properties of moringa flowers

A fresh and healthy PKM – 2 variety moringa flowers procured directly from a farmer producer organization in Madurai was used in the study. Fresh moringa flowers were analysed for their physicochemical characteristics, viz., moisture and ascorbic acid, by the methods given by AOAC.^{[50],[51],[52]} The protein-Kjeldahl method was used to measure total nitrogen content. Crude fibre, β – carotene – HPLC method total antioxidant activity (TAA), total flavonoids, total phenols (TP) and minerals were analysed.^{[53],[54],[55]}

Phytochemical screening of fresh moringa flowers

Extraction of bioactive compounds from fresh moringa flowers was carried out using different solvents like methanol, ethanol, chloroform, hexane, acetone and ethyl acetate. 20 grams of the fresh moringa flower samples were taken into a 250 ml beaker. After that, 150 ml of the different solvents was added and centrifuged at 1000 rpm for 2 hr until agitation.^{[56],[57],[58]} Then, the samples were allowed to continue the extraction process at room temperature for 72 hr. Finally, each sample solvent mixture was filtered, and the crude extract was taken for phytochemical screening.^{[59],[60],[61],[62]} Qualitative phytochemical analysis was performed with each solvent extract of the moringa flowers to determine the presence of alkaloids, tannins, flavonoids, steroids, terpenoids and saponins.^{[63],[64],[65]}

Processing for the preparation of dried moringa flower powder

Healthy mature moringa flowers were selected, and then fresh moringa flowers were steam blanched for 2-5 min until tender and sulphated at 0.1% for 10 min to preserve the colour and to improve storage durability. After that, a dehydration process was performed with freeze-drying.^{[66],[67],[68]} A Liotop® L101 tabletop freeze drier was used for the freeze-drying process. Freeze drying was started at 0.15 mbar after moringa flowers were placed on unheated shelves (15 Pa). The ambient radiation that reached the samples through the clear glass drying chamber provided the sublimation energy. The samples were then lyophilized for 24 hours at varied low temperatures, such as-40,-50, and-60°C. The freeze-dried powder was properly packed and stored at ambient temperature.^{[69],[70],[71],[72]}

Statistical analysis

Data analysis was performed in a completely randomized design (CRD) using SPSS 14.0 for Windows.

Results and Discussion

Proximate composition of fresh and freeze-dried moringa flower powder

The Proximate composition of moringa flowers included moisture-74.95%, protein-6.68g, crude fibre-1.9 g, β-carotene-18.85mg and ascorbic acid-282.32 mg. The moringa flowers have much-valued nutraceutical properties, where the total antioxidant activity, total flavonoids and total phenols were 226.14mg 100 g^-1, 17.98mg RE g^-1 extract and 63.19mg GAE g^-1 extract, respectively, and with mineral contents of calcium – 48.8, iron-2.85, phosphorous-92.18, potassium-367.4 and magnesium 48.12 mg 100 g^-1.^{[73],[74],[75]} Similar results through the chemical characteristics of the moringa flower which shows the protein 2.5 g, carbohydrate 3.7 g, fibre 4.8 g, vitamin C 120 mg, calcium 30 mg, magnesium 24 mg, phosphorus 110 mg, potassium 259 mg and iron 5.3 mg per 100 g. Shailendra et al., 2016 analyzed the moringa and it contains moisture-89.99%, ascorbic acid-127.39 mg per 100 g, calcium-31.95 mg per 100 g, iron-5.35 mg per 100 g, phosphorus-107.85 mg per 100 g, crude fibre-4.00 per cent and vitamin A-185.06 IU and his results were accordance with the present investigation.^{[76],[77],[78],[79]} Thurber and Fahey stated that M. oleifera parts are rich in protein, total carotenoids (40139 μg/100 g), nearly 47.8% β-carotene, 6.6 mg/g ascorbic acid, 22.4 mg/g iron, 6.3 mg/g calcium and 0.9 g/100 g fibre which reduce malnutrition problems among the community and have great potential to combat micronutrient deficiencies.^{[80],[81],[82],[83]} The Physico-chemical composition of the FD-MFP is presented in [Table 1].

Table 1: Physicochemical characteristics of fresh and dried moringa flowers

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The moisture content of the MFP varied between 4.53 (45°C) and 4.075% (65°C). The protein and crude fibre contents of FD-MFP were 18.13-23.92and 9.88-12.03 per 100 g, respectively, at different temperatures. The β – carotene content of powder dried at 55°C was higher (58.41 mg per 100 g) than those dried at 45°C and 65°C.^{[84],[85],[86],[87]} Similarly, the ascorbic acid content was also higher (305.81mg per 100 g) in MFP dried at 55°C, followed by 45°C (285.09 mg) and 65°C (211.48 mg). The total phenol, flavonoid and antioxidant activities were 234.02 to 241.08 mg/GAE, 16.18 to 19.34 mg/RE and 448.12 to 460.18mg per 100 g, respectively, at different temperature levels.^{[77],[88],[89]} The maximum retention of calcium, iron, phosphorus, potassium and magnesium was found at drying temperatures of 45°C and 55°C compared with 65°C.

The same results are in agreement with the literature reported. Manju et al., 2021 in freeze-dried moringa flowers shows moisture-3.70 ± 0.06, crude protein-16.48 ± 0.34, crude fibre-7.90b ± 0.16, total phenols-192.21b ± 3.70 and vitamin C-174.41d ± 2.89. Silva et al., 2019 and reported the same results in freeze-dried moringa at different temperatures their results were Moisture content (5.88%), fat (8.15%), crude protein (27.02%), crude fibre (13.39%) and carbohydrate (37.20%) Potassium (2.40%), Phosphorus (5.40 Mg/g), Iron (6.27 Mg/L), Magnesium (5.19 Mg/L) and Calcium (4.65%).^{[90],[91],[92]} Raising the air-drying temperature (65°C) resulted in a greater loss of heat sensitivity nutrients such as carotene and ascorbic acids due to thermal deterioration and oxidation. Low moisture combined with a higher temperature for a longer period resulted in a greater reduction in TP and TAA. Increased phenolic content was associated with better antioxidant activity at optimal temperature due to the phenolic compound's high hydrogen atom-donating ability.^[93] When the drying temperature was raised above the optimal threshold, the leaf cell walls were damaged, causing the release of oxidative and hydrolytic enzymes, which destroyed the antioxidant properties.^[94]

Qualitative phytochemical screening of fresh moringa flower

The present qualitative screening results indicate phytochemicals were highly present in methanol and ethanol extracts, and a lower amount of phytochemicals was noticed in the chloroform extract. The same results were recorded in methanol and ethanolic moringa extracts respectively. Intracellular ingredients are extracted from the cellular membrane by methanol and ethanol solvents due to their high penetration capacity. In diluted ethanol, the concentration of flavonoids was higher due to amplified polarity.^[95] Extraction of bioactive compounds from medicinal plants is limited to solvents (chloroform and hexane) with very low strength and polarity.^[96] Among the phytochemicals, tannins and flavonoids were highly detected in methanol and ethanol extracts when compared to other solvent extracts such as chloroform, hexane, acetone and ethyl acetate. Okwu DE and Okwu ME 2004 stated the higher concentration of flavonoids in moringa parts will also help to protect against allergies, platelet aggregation, inflammation, free radicals, viruses, microbes, ulcers and tumours [Table 2].

Table 2: Qualitative phytochemicals screening of fresh moringa flower

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Conclusion

For both fresh and dried moringa flower powder, the effects of drying temperature were investigated. The optimal drying temperature of 55°C results in improved physicochemical features such as – carotene (55.41 mg), total antioxidant (460.18 mg), and flavonoids (19.34 mg/RE), phenol (234.13 mg/GAE), and vitamin C content (485.09 mg). According to the findings of this study, FD drying is one of the best drying techniques for preserving nutritional quality features while also being efficient and cost-effective for the entire food processing industry. Moringa flower powder, which has been freeze dried, can be used to make novel functional foods including vegetable soup, energy bars, energy drinks, extruded goods, and incorporated food products that can be employed in nutritional intervention programmes.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Abbas RK, Elsharbasy FS, Fadlelmula AA. Nutritional values of Moringa oleifera, total protein. Amino acid, vitamins, minerals, carbohydrates, total fat and crude fiber, under the semi-arid conditions of Sudan. J Microb Biochem Technol 2018;10:56-8.
2.	Ademiluyi AO, Aladeselu OH, Oboh G, Boligon AA. Drying alters the phenolic constituents, antioxidant properties, α-amylase, and α-glucosidase inhibitory properties of Moringa (Moringa oleifera) leaf. Food Sci Nutr 2018;6:2123-33.
3.	Aliyu A, Chukwuna UD, Omoregie EH, Folashade KO. Qualitative phytochemical analysis of the leaf of Moringa oleifera lam. From three climatic zones of Nigeria. J Chem Pharm Res 2016;8:93-101.
4.	Kumar R, Saha P, Lokare P, Datta K, Selvakumar P, Chourasia A. A systemic review of Ocimum sanctum (Tulsi): Morphological characteristics, phytoconstituents and therapeutic applications. Int J Res Appl Sci Biotechnol 2022;9:221-6.
5.	Anwar F, Latif S, Ashraf M, Gilani AH. Moringa oleifera: A food plant with multiple medicinal uses. Phytother Res 2007;21:17-25.
6.	Arun Prabhu R, Prem Rajan A, Santhalia S. Comparative analysis of preservation techniques on Moringa oleifera. Asian J Food Agro Ind 2011;4: 65-80.
7.	AzevedoÍM, Araújo-Filho I, Teixeira MM, Moreira MD, Medeiros AC. Wound healing of diabetic rats treated with Moringa oleifera extract. Acta Cir Bras 2018;33:799-805.
8.	Bamishaiye EI, Olayemi FF, Awagu EF, Bamishaiye OM. Proximate and phytochemical composition of Moringa oleifera leaves at three stages of maturation. Adv J Food Sci Technol 2011;3:233-7.
9.	Barimah J, Yanney P, Laryea D, Quarcoo C. Effect of drying methods on phytochemicals, antioxidant activity and total phenolic content of dandelion leaves. J Food Nutr 2017;5:136-41.
10.	Boudieb K, Slimane-Ait Kaki SA, Amellal-Chibane H. Effect of maturation degree on the fixed oil chemical composition, phenolic compounds, mineral nutrients and antioxidant properties of Pistacia lentiscus L. Fruits. Not Botanicae Horti Agrobotanici Cluj Napoca 2019;47:836-47.
11.	Chen J, Li F, Li Z, McClements DJ, Xiao H. Encapsulation of carotenoids in emulsion-based delivery systems: Enhancement of β-carotene water-dispersibility and chemical stability. Food Hydrocolloids 2017;69:49-55.
12.	Kinki A, Mezgebe A, Lema T. Antioxidant and sensory properties of herbal teas formulated from dried Moringa (Moringa stenopetala) and Stevia (Stevia rebaudiana Bertoni) Leaves. 2020.
13.	Klungboonkrong V, Phoungchandang S, Lamsal B. Drying of orthosiphonaristatus leaves: Mathematical modeling, drying characteristics, and quality aspects. Chem Eng Commun 2018;205:1239-51.
14.	Lakshmipriya G, Doriya K, Devarai SK. Moringa oleifera: A review on nutritive importance and its medicinal application. Food Sci Human Wellness 2016;5:49-56.
15.	Lim YY, Lim TT, Tee JJ. Antioxidant properties of several tropical fruits: A comparative study. Food Chem 2007;103:1003-8.
16.	Singh MK, Kumar A, Kumar R, Satheesh Kumar P, Selvakumar P, Chourasia A. Effects of repeated deep frying on refractive index and peroxide value of selected vegetable oils. Int J Res Appl Sci Biotechnol 2022;9:28-31.
17.	Manju KM, Kumar N. Effect of fluidized-bed and freeze-drying techniques on physicochemical, nutritional, thermal, and structural properties of Moringa oleifera flowers, leaves, and seeds. J Food Process Preserv 2021;45:e15719.
18.	Marcel A, Hubert M, Bienvenu MJ, Pascal O. Physicochemical characteristics and biochemical potential of Moringa oleifera Lam. (Moringaceae). Der Pharm Lettre 2016;8:43-7.
19.	Meda A, Lamien CE, Romito M, Millogo J, Nacoulma OG. Determination of the total phenolic, flavonoid and proline contents in Burkina Fasan honey, as well as their radical scavenging activity. Food Chem 2005;91:571-7.
20.	Nweze NO, Nwafor FI. Phytochemical, proximate and mineral composition of leaf extracts of Moringa oleifera Lam. from Nsukka, South-Eastern Nigeria. 2014.
21.	Okwu DE, Okwu ME. Chemical composition of Spondias mombin Linn plant parts. J Sustain Agric Environ 2004;6:140-7.
22.	Quettier-Deleu C, Gressier B, Vasseur J, Dine T, Brunet C. Luyckx M phenolic compounds and antioxidant activities of buckwheat (Fagopyrum sculentum Moench) hulls and flour. J Ethnopharmacol 2000;72:35-42.
23.	Ranganna S. Manual of Analysis of Fruits and Vegetables Products. New Delhi: Tata McGraw Hill publishing Co, Ltd.; 1995. p. 1-2, 7-13.
24.	Sekhar C, Venkatesan N, Murugananthi D, Vidhyavathi A. Status of value addition and export of Moringa produce in Tamil Nadu a case study. Econ Bot 2018;34:276-83.
25.	Patni S, Bijarnia KK, Enaniya H, Sharma K, Lal B, Maheshwari RK. Drumstick tree: A miracle forwell-beingand sociopecuniary diverse therapeutic applicability. Int J Chem Pharm Sci 2016;4:108-14.
26.	Silva MA, Ayed C, Foster T, Camacho MD, Martínez-Navarrete N. The impact of freeze-drying conditions on the physico-chemical properties and bioactive compounds of a freeze-dried orange puree. Foods 2019;9:32.
27.	Thurber MD, Fahey JW. Adoption of Moringa oleifera to combat undernutrition viewed through the lens of the “Diffusion of innovations” theory. Ecol Food Nutr 2009;48:212-25.
28.	Wang GX, Han J, Feng TT, Li FY, Zhu B. Bioassay-guided isolation and identification of active compounds from Fructus Arctii against Dactylogyrus intermedius (Monogenea) in goldfish (Carassius auratus). Parasitol Res 2009;106:247-55.
29.	Loganathan V, Selvakumar P. A study of the physico-chemical and phytochemical parameters of leaves of Mallotus rhamnifolius. Int J Pharmacogn Phytochem Res 2017;9:858-63.
30.	Bharali R, Tabassum J, Azad MR. Chemomodulatory effect of Moringa oleifera, Lam, on hepatic carcinogen metabolising enzymes, antioxidant parameters and skin papillomagenesis in mice. Asian Pac J Cancer Prev 2003;4:131-9.
31.	Brown JE, Rice-Evans CA. Luteolin-rich artichoke extract protects low density lipoprotein from oxidation in vitro. Free Radic Res 1998;29:247-55.
32.	Cáceres A, Saravia A, Rizzo S, Zabala L, De Leon E, Nave F. Pharmacologic properties of Moringa oleifera. 2: Screening for antispasmodic, antiinflammatory and diuretic activity. J Ethnopharmacol 1992;36:233-7.
33.	Devi P. Principles and Methods of Plant Molecular Biology, Biochemistry and Genetics. Agrobios; 2003. Donli PO, Dauda H. Evaluation of aqueous Moringa seed extract as a seed treatment biofungicide for groundnuts. Pest Manag Sci 2003;59:1060-2.
34.	Eilert U, Wolters B, Nahrstedt A. The antibiotic principle of seeds of Moringa oleifera and Moringa stenopetala. Planta Med 1981;42:55-61. Fahey J. Moringa oleifera: A review of the medical evidence for its nutritional, therapeutic, and prophylactic properties. Part 1. Trees Life J 2005;1:231.
35.	Selvakumar P, Loganathan V. Phytochemical screening and antioxidant activity of red flowered Mirabilis Jalapa leaf in different solvents. Int J Pharm Bio Sci 2012;3 Suppl 4:440-6.
36.	Ghebremichael KA, Gunaratna KR, Henriksson H, Brumer H, Dalhammar G. A simple purification and activity assay of the coagulant protein from Moringa oleifera seed. Water Res 2005;39:2338-44.
37.	Gilani AH, Aftab K, Suria A, Siddiqui S, Salem R, Siddiqui BS. Pharmacological studies on Hypotensive and spasmolytic activities of pure compounds from Moringa oleifera. Phytother Res 1994;8:87.
38.	Gupta M, Mazumder UK, Chakrabarti S. CNS activities of methanolic extract of Moringa oleifera root in mice. Fitoterapia 1999;70:244.
39.	Selvakumar P, Loganathan V. Physicochemical analysis of Alocasia sanderiana W. Bull Asian J Pharm Anal 2016;6:31-4.
40.	Just MJ, Recio MC, Giner RM, Cuéllar MJ, Máñez S, Bilia AR, et al. Anti-inflammatory activity of unusual lupane saponins from Bupleurum fruticescens. Planta Med 1998;64:404-7.
41.	Kokate CK. Practical Pharmacognosy. 3^rd ed. NewDelhi: Vallabh Prakashan; 1994. Krings U, Berger RG. Antioxidant activity of roasted foods. Food Chem 2001;72:223-9.
42.	Madsen M, Schlundt J, Omer EF. Effect of water coagulation by seeds of Moringa oleifera on bacterial concentrations. J Trop Med Hyg 1987;90:101-9.
43.	Mehta K, Balaraman R, Amin AH, Bafna PA, Gulati OD. Effect of fruits of Moringa oleifera on the lipid profile of normal and hypercholesterolaemic rabbits. J Ethnopharmacol 2003;86:191-5.
44.	Morton JF. The horseradish tree, Moringa pterygosperma (Moringaceae): A boon to arid lands? Econ Bot 1991;45:318.
45.	Odee D. Forest biotechnology research in Drylands of Enya: The development of Moringa species. Dryl Biodivers 1998;12:7.
46.	Oliveira JT, Silveira SB, Vasconcelos KM, Cavada BS, Moreira RA. Compositional and nutritional attributes of seeds from the multiple purpose tree Moringa oleifera Lamarck. J Sci Food Agric 1999;79:815.
47.	Selvakumar P, Loganathan V. Preliminary phytochemical investigation of extract of leaves and stem of Euphorbia Hirta. Int J Curr Sci 2012, p. 48-51.
48.	Craig WJ. Health-promoting properties of common herbs. Am J Clin Nutr 1999;70:491S-499S.
49.	Sánchez-Machado DI, Núñez-Gastélum JA, Reyes-Moreno C, Ramírez-Wong B, López-Cervantes J. Nutritional quality of edible parts of Moringa oleifera. Food Anal Methods 2010;3:175-180.
50.	Siddhuraju P, Becker K. Antioxidant properties of various solvent extracts of total phenolic constituents from three different agroclimatic origins of drumstick tree (Moringa oleifera Lam.) leaves. J Agric Food Chem 2003;51:2144-55.
51.	Nindo CI, Sun T, Wang SW, Tang J, Power JR. Evaluation of drying technologies for retention of physical quality and antioxidants in asparagus. LWT Food Sci Technol 2003;36:507-16.
52.	Raghavan GS, Rennie TJ, Sunjka PS, Orsat V, Phaphuangwittayakul W, Terdtoon P. Overview of New Techniques for Drying Biological Material. Halkididi, Greece: 11^th International Drying Symposium (IDS 98); 2005.
53.	Achariyaviriya S, Soponronnarit S, Terdyothin A. Mathematical model development and simulation of heat pump fruit dryer. Drying Technol 2000;18:479-91.
54.	Selvakumar P, Loganathan V. Phytochemical screening and in vitro antioxidant activity of male and female flowers ethanolic extracts of Cocos nucifera. LS. Int J Life Sci 2016;5:127-31.
55.	Phoungchandang S, Sanchai P, Chanchotikul K. The development of dehumidifying dryer for a Thai herb drying (Kapro leaves). Food J 2003;33:146-55.
56.	Ogura H, Yamamoto T, Otsubo Y. A control strategy for a chemical heat pump dryer. Dry Technol 2005;23:1189-203.
57.	Saensabai P, Prasertsan S. Condenser coil optimization and component matching of heat pump dryer. Dry Technol 2007;25:1571-80.
58.	Pal US, Khan MK. Calculation steps for the design of different components of heat pump dryer under constant drying rate condition. Dry Technol 2008;26:864-72.
59.	Prasertsan S, Saen-Saby P. Heat pump drying of agricultural materials. Dry Technol 1998;16:235-50.
60.	Chou SK, Chua KJ. New hybrid drying technologies for heat sensitive foodstuffs. Trends Food Sci Technol 2001;12:359-69.
61.	Boonnattakorn R, Phoungchandang S, Leenanon B, Khajarern S, Khajarern J. The comparative study of garlic powder processing by heated air and dehumidifier heat pump dryer. Food J 2004;34:248-60.
62.	Chottanom P, Phoungchandang S. The development of osmotically dehydrated mangoes using conventional drying and dehumidified drying. Chem Eng Trans 2005;6:897-902.
63.	Hawlader MN, Perera C, Tian M. Comparison of the retention of 6-gingerol in drying of ginger under modified atmosphere heat pump drying and other drying methods. Dry Technol 2006;24:51-6.
64.	Rahman SM, Islam MR, Mujumdar AS. A study of couple heat and mass transfer in composite food products during convective drying. Dry Technol 2007;25:1359-68.
65.	Alves-Filho O, Eikevik TM, Mulet A. Kinetics and mass transfer during atmospheric freeze drying of red pepper. Dry Technol 2007;25:1155-61.
66.	Selvakumar P, Loganathan V. In vitro pharmacology studies on Alocasia sanderiana W. Bull. J Pharmacogn Phytochem 2016;5:114-20.
67.	Phoungchandang S, Srinukroh W, Leenanon B. Kaffir lime leaf (Citrus hystric DC.) drying using tray and heat pump dehumidified drying. Dry Technol 2008;26:1602-9.
68.	Phoungchandang S, Tochip L, Srijesdaruk V. White mulberry leaf drying by tray and heat pump dehumidified dryers. World J Agric Sci 2008;4:844-51.
69.	Potisate Y, Phoungchandang S. Chlorophyll retention and drying characteristics of ivy gourd leaf (Coccinia grandins Voigt) using tray and heat pump–assisted dehumidified air drying. Dry Technol 2010;28:786-97.
70.	Phoungchandang S, Kongpim P. Modeling using a new thin layer drying model and drying characteristics of sweet basil (Ocimum baslicum Linn.) using tray and heat pump–assisted dehumidified drying. J Food Process Eng 2012;35:851-62.
71.	Trirattanapikul W, Phoungchandang S. Microwave blanching and drying characteristics of Centella asiatica (L.) urban leaves using tray and heat pump-assisted dehumidified drying. J Food Sci Technol 2014;51:3623-34.
72.	Tulasidas TN, Raghavan GS, Mujumdar AS. Microwave drying of grapes in a single mode cavity at 2450 MHz. I. Drying kinetics. Dry Technol 1995;13:1949-71.
73.	Wolf W, Spiess WE, Jung G. Standardisation of isotherm measurements (COST-project 90 and 90BIS). In: Simatos D, Muton JL, editors. Properties of Water in Foods. Dordrecht, the Netherlands: Martinus Nijhoff; 1985. p. 611.
74.	Arabhosseini A, Huisman W, Müller J. Modeling of desorption of alfalfa (Medicago sativa) stems and leaves. Ind Crops Prod 2011;34:1550-5.
75.	He X, Lau AK, Sokhansanj S, Lim CJ, Bi XT, Melin S, et al. Moisture sorption isotherms and drying characteristics of aspen (Populus tremuloides). Biomass Bioengergy 2013;57:161-7.
76.	Selvakumar P, Loganathan V. In vitro phytochemical, antimicrobial and antioxidant activity studies on Alocasia sanderiana W. Bull. Indo Am J Pharm Sci 2016;3:252-64.
77.	Dadali G, Demirhan E, Özbek B. Color change kinetics of spinach undergoing microwave drying. Dry Technol 2007;25:1713-23.
78.	Association of Official Analytical Chemists. Official Methods of Analysis; Association of Official Analytical Chemists. Arlington, VA: Association of Official Analytical Chemists; 2000.
79.	Phoungchandang S, Woods JL. Moisture diffusion and desorption isotherms for banana. J Food Sci 2000;64:651-7.
80.	Askari GR, Eman-Djomeh Z, Mousavi SM. An investigation of the effects of drying methods and conditions on drying characteristics and quality attributes of agricultural products during hot air and hot air/microwave-assisted dehydration. Dry Technol 2009;27:831-41.
81.	Lako J, Trenerry CV, Wahlqvist M, Wattanapenpaiboon N, Sotheeswaran S, Premier R. Phytochemical flavonols, carotenoids and the antioxidant properties of a wide selection of Fijian fruit, vegetables and other readily available foods. Food Chem 2007;101:1727-41.
82.	Sultana B, Anwar F. Flavonols (kaempeferol, quercetin, myricetin) contents of selected fruits, vegetables and medicinal plants. Food Chem 2008;108:897-4.
83.	Kouhila M, Kechaou N, Otmani M, Fliyou M, Lahsasni S. Experimental study of sorption isotherms and drying kinetics of Moroccan Eucalyptus globulus. Dry Technol 2002;20:2027-39.
84.	Kaur D, Wani AA, Sogi DS, Shivhare US. Sorption isotherms and drying characteristics of tomato peel isolated from tomato pomace. Dry Technol 2006;24:1515-20.
85.	Phoungchandang S, Nongsang S, Sanchai P. The development of ginger drying using tray drying, heat pump dehumidified drying and mixed mode solar drying. Dry Technol 2009;27:1123-31.
86.	Selvakumar P, Loganathan V. In vitro antibacterial and antifungal activities of Morinda tinctoria leaf in different solvents. Pharmacia 2013;2:52-8.
87.	McMinn WA. Thin layer modeling of the convective, microwave, microwave convective and microwave vacuum drying of lactose powder. J Food Eng 2006;72:113-23.
88.	Evin D. Thin layer drying kinetics of Gundelia tournefortii L. Food Bioproducts Process 2012;90:323-32.
89.	Wang Z, Sun J, Chen F, Liao X, Hu X. Mathematical modeling on thin layer microwave drying of apple pomace with and without hot air pre-drying. J Food Eng 2007;80:536-44.
90.	Al-Harahsheh M, Al-Muhtaseb AH, Magee TR. Microwave drying kinetics of tomato pomace: Effect of osmotic dehydration. Chem Eng Process J 2009;48:524-31.
91.	Selvakumar P. Biomedical activities of florasol. J Prev Diagn Treat Strat Med 2022;1:158-62.
92.	Demirhan E, Özbek B. Microwave-drying characteristics of basil. J Food Process Preserv 2010;34:476-94.
93.	Özbek B, Dadali G. Thin layer drying characteristics and modeling of mint leaves undergoing microwave treatment. J Food Eng 2007;83:541-9.
94.	Demirhan E, Özbek B. Thin-layer drying characteristics and modeling of celery leaves undergoing microwave treatment. Chem Eng Commun 2011;198:957-75.
95.	Sarimeseli A. Microwave drying characteristics of coriander (Coriandrum sativum L.) leaves. Energy Convers Manag 2011;52:1449-53.
96.	Vega A, Uribe E, Lemus R, Miranda M. Hot-air drying characteristics of aloe vera (Aloe barbadensis Miller) and influence of temperature on kinetic parameters. LWT Food Sci Technol 2007;40:1698-707.