An updated phytochemical and pharmacological review on Malabar Spinach ( Basella alba or Basella rubra )

Cancer, autoimmune diseases, microbial infections and oxidative stress are becoming unavoidable threats in recent times. Despite advances in conventional treatments such as surgery, radiotherapy and chemotherapy, problems related to these therapies such as side effects, opportunistic infections and the development of drug resistance remained unsolved. Therefore, the need of the hour is to develop novel treatment modalities using plant derivatives which act as effective therapeutic agents and have minimal side effects. Basella alba is one such plant which contains various phytochemicals viz. flavonoids, alkaloids, phytosterols, tannins and triterpenoids etc., which helps in curing various diseases. The main aim of the present review is to highlight the phytochemical and pharmacological investigation carried out on the plant so that the more pharmacological studies could be conducted to investigate the untapped potential. Based on the published evidences on various databases, findings suggest that various parts of B. alba are used as antioxidant, anticancer, antibacterial, anti-inflammatory, antiulcer and many other diseases. Finally, it can be concluded that B. alba may be appealed as a good source of pharmacologically active compounds to develop new drugs.


Introduction
Medicinal plants have been a good source of therapeutic agents since ancient times to treat human diseases.Despite the major advances in the modern medicine, the development of new medicines from natural products is still has its importance due to the wide spread belief that natural medicine is healthier than synthetic drug.Since 1980, World Health Organization (WHO) has been encouraging many countries to develop traditional medicine and phytotherapy.The main Indian traditional system of medicine namely Ayurveda and Siddha, are primarily plant-based system.As per WHO, about 80% of the population in the world relays on the traditional medicine for the treatment of various diseases.Therefore, the development of traditional medicine is essential.
In this regard, Basella alba is one such plant which is a good source of many phytochemicals responsible for cure of various diseases.It is a fast-growing plant reaching 10 m in length.It is a leafy vegetable.The leaves are thick, heart shaped which have mild flavor and mucilaginous texture.The size of the leaves varies from 3 to 9 cm in length and 4 to 8 cm in width.The flowers are inconspicuous, bisexual white flowers borne on axillary spikes or branching peduncles.Its fruits are fleshy and stalk less, ovoid or spherical in shape, 5 to 6 mm, and purple when mature.[1] It is native of southern Asia and popularly known as Malabar spinach, Indian spinach.The stem of the cultivar Basella rubra is reddish purple.In eastern and southern parts of India, the leaves and stems of the plant are used in cooking.It is widely distributed in the tropics and often cultivated in warm temperature areas of both the eastern and western hemisphere.It is cultivated in almost whole of India, especially in lower Bengal and Assam, it is an important part of diet-stated by Watt.It is considered as food plant in the Philippine, and boiled and eaten like spinach.The leaves are used to poultice sore in both Malaya and India.[3] Nowadays, it is widely grown for its nutritive value.

Traditional uses
The plant has been known to be a demulcent, a diuretic and an emollient action.The entire plant is used in Chinese medicine where it is claimed to reduce fever and neutralize poison.The pulped or bruised leaves are used as a poultice for ulcers and to hasten the maturation of abscesses.The decoction of the leaves is believed to have laxative properties, and is used to treat constipation in pregnant women and children.The juice of the plant is used as a dye for official seals, as a rouge on the facial skin and food coloring.[1] Especially the ones with red stem shows anti-inflammatory and antiulcer effects.[2] Basella plant species contain betacyanin, carotenoids, bioflavonoids, β-sitosterol and lupeol which are reported to have anti-oxidant, anti-proliferative, anti-microbial and anti-inflammatory effects etc., and help in curing various diseases, namely anti-cancer, anti-viral, anti-ulcer, anti-cholesterol, hypoglycemic, wound healing and androgenic from the ancient times.Leaf juice is used to treat catarrh.[7] The ayurveda treatment in India has been used B. alba leaves and stem for anti-cancer such as melanoma, leukemia and oral cancer.[8]

Phytochemicals reported in the plant
Hema Arya et al., 2021 reported that preliminary qualitative analysis is one of the useful methods to detect various bioactive compounds which is responsible for various pharmacological activities like antioxidant value depends on presence of flavonoid and phenolic compounds, further contributed to cure cancer etc., [4].They analyzed total phenolic content and total flavonoid content of Basella alba leaves extract and reported that the alcoholic, ethyl acetate and methanolic extracts of plant contains good phenolic and flavonoid contents.The methanolic extract showed high values as 533.28±0.16 and 446.02±0.1 total phenolic content and total flavonoid content respectively.These phenolic flavonoid compounds are capable of preventing the aging, inflammatory and cell proliferation.Malabar spinach was found to be rich in kaempferol at a concentration of 1.4 mg/100g which is a flavonoid protective against cardiovascular diseases and cancer.Kumar et al., (2021) performed isolation, identification and characterization of flavonoids from B. alba L. using TLC and IR and confirmed by GC-MS analysis.This study reported that 49 compounds were found in GC-MS analysis and 1-Methyl-4-isopropylcyclohexyl 2-hydroperfluorobutanoate was found in highest amount.[29] Basella alba contains carotenoids, betacyanins, triterpene oligoglycosides, organic acids, basellasaponins A, B, C and D. The leaf extract contains vitamin A, C, E, B1, B2, B3, B9, folic acid, protein, fat and minerals such as magnesium, calcium and iron.The preliminary phytochemical screening of various leaf extracts of the plant exhibited high levels of flavonoids, poly phenols, moderate levels of alkaloids, tannins, glycosides, carbohydrates, vitamins, minerals and low levels of saponins.Krishnendu Pal (2016) this study evaluated the cytotoxic activity of methanolic extract of B. alba whole plant on human leukemic cell lines U937 and murine macrophage cell line RAW 264.7cells using MTT assay.The results showed that the extract has selectivity for leukemic cells and exerts no effect on the RAW 264.7 cells.The extract at concentrations of 10µg to 200µg significantly inhibited the growth of U937 cells in a concentration and time dependent manner.The IC50 value was found to be 24.54µg/ml.DNA laddering assay by gel electrophoresis showed its apoptotic activity.[11] Rathee Sushila et al., (2010) this study evaluated the cytotoxic effect of methanolic extract of Basella alba whole plant on Jurkat and lung cancer (A549) cell lines.The results showed that the extract exhibited cytotoxic effect against both cell lines but the activity was very much significant against Jurkat cell lines.At 100µg/ml concentration, the percentage cell viability in Jurkat and A549 cells was found to be 41.78±1.25  Serum was analyzed for hepatic and renal function biomarkers in the treated animals.The treatment with 100 and 250mg/kg body weight significantly reduced the elevated renal and hepatic biomarkers.These findings in this study suggested that the plant is a potential chemoprotective agent against acrylamide induced oxidative stress in wistar rats. [25] Bamidele O et al., (2020) reported that the methanol extracts of B. alba leaves alleviate stress in rats.In stressed rats, there were substantial increases in fasting blood glucose and white blood cell count while there were substantial decreases in superoxide dismutase activity and glutathione concentration.In extract treated rats, there were significant decreases in blood glucose and white blood cell count and significant increases in superoxide dismutase and glutathione concentrations.The results from this study suggested that the plant alleviates hyperglycemia, chronic activation of immune system and generation of free radicals due to stress in wistar rats.[26] Dennis Seyi Arokoyo et al., (2018) evaluated the antioxidant activity of B. alba aqueous leave extract in blood, pancreas, and gonadal tissues of diabetic male wistar rats.The extract significantly lowered fasting blood sugar in rats.
The results showed that the plant extract exerts antioxidant effects in the gonads by enhancing antioxidant parameters in circulating blood, but not necessarily in the gonadal tissues. [13]

Hepatoprotective activity
Mathew Folaranmi Olaniyan (2017) tested hepatoprotective activity of ethanolic and aqueous extracts of Malabar spinach in rabbits overdosed with paracetamol.The results showed lower AST (aspartate aminotransferase), ALT (alanine transaminase), TBA (total bile acid) and LDH (lactate dehydrogenase) values than paracetamol alone treated rabbits, which indicates that the plant has good hepatoprotective activity.[14] Saibal das et al., (2014) evaluated the hepatoprotective activity of aqueous extracts of leaves of B. alba in albino rats.
Hepatoprotective effect was evaluated by comparing serum bilirubin, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, proteins, alkaline phosphatase and liver histology.The results were well comparable and even in some respects superior to standard drug silymarin.The plant extract at a concentration of 100mg/kg/day orally had significant hepatoprotective effect in paracetamol induced hepatotoxicity in albino rats.[15] 3.

Vijender Kumar et al., (2011) tested in-vitro anti-inflammatory activity of methanolic and aqueous leaf extracts of
Basella alba Linn var alba by human red blood cell membrane stabilization method (HRBC).The aqueous extract showed the most significant membrane stabilizing action.The methanolic extract showed 68.38±1.18percentage protection at a concentration of 400µg/ml.The maximum percentage protection is 71.89±1.22 at 400µg/ml concentration of aqueous extract.Based on the results they concluded that the plant has a significant anti-inflammatory activity.[17] 3.5.Antiulcer activity P. Venkatalakshmi et al., (2012) tested anti-ulcer effect of B. alba leaf extract in aspirin induced albino rats and revealed that the plant has been endowed with gastro protective potential.In this study, B. alba leaf extract was found to alter the observed ulcer parameters like ulcer index, percentage of ulcer inhibition, gastric PH, pepsin content, glutathione reductase (GSH), vitamin C and E. The animals co treated with ethanolic leaf extract of Basella alba (200mg/kg body weight) and aspirin (150mg/kg) for 21 days showed 8.59±0.19ulcer index and 66% ulcer inhibition.Whereas animals treated with ethanolic leaf extract of the plant alone (200mg/kg) for 21 days showed 0.4±0.03ulcer index and 99% ulcer inhibition.The pH of gastric juice was found to be increased in plant extract treated animals (4.2±0.3)compared to aspirin treated animals (2.17±0.12).The pepsin content was reduced in plant extract treated animals (2.4±0.05)compared to aspirin alone treated animals (4.3±0.1).[18] 3.6.Hypocholesterolemia effect

Discussion
B. alba contains the terpenoid Caryophyllene which has remarkable nephroprotective, cardioprotective, neuroprotective, gastroprotective and immunomodulatory properties.The various fatty acids present in the plant showed anti anemic, dyslipidemic, antitumor, anti-atherosclerotic, anti-inflammatory and antioxidant effects.The alcoholic, phenolic and aromatic compounds present in this plant suppresses total cholesterol, triglyceride level and fat accumulation which makes them to show anti-atherosclerotic effect.The vitamins and minerals present in this plant are good hematinics.B. alba is apparent to keep antioxidant, anti-inflammatory and cytotoxic properties which makes it good for the development of anticancer therapies.Due to the presence of antioxidant and immunomodulatory effects, this plant helps in treating various stress related and auto immune disorders like diabetes, neurodegenerative diseases and cancer etc.,

Conclusion
In summary, this review suggests that B. alba is a great source of valuable phytochemicals such as flavonoids, terpenoids, fatty acids, polyphenols, vitamins, proteins and minerals.According to the scientific reports on various databases, B. alba and its extracts are used to treat many diseases in various countries.This plant owns many pharmacological activities.Among them, anticancer, antimicrobial, anti-inflammatory, antioxidant, nephroprotective, antidiabetic, antiulcer, wound healing, CNS depressant and androgenic properties are significant.Therefore, B. alba may be one of the great sources of traditional medicines.

Table 1
[2]tocomponents identified in GC-MS analysis of various extracts of Basella alba leaves and their reported biological activities .9mg/g)andcarotenoidcontent (0.28mg/g) compared to other parts.The terpenoid content and alkaloid content are higher in leaves fraction of B. alba which are 0.89mg/g and 1.61mg/g respectively.[reportedbyGabrielOlaniran Adegoke et al., 2017] -[6].This plant has also antioxidant compounds.The stem, leaves and flowers of this plant have a natural color pigment Anthocyanin.[2] [47]minMethanol Lowers total cholesterol and LDL cholesterol[19], antioxidant and anticancer[47].[5]B. alba contains better phenolic and flavonoid contents compared to B. rubra.The fruit fraction of B. alba contains the highest total phenolic content (5.07 mg/ml), total flavonoid content (9.87 mg/g), saponin content, tannin content (5

3. Reported pharmacological activities of Basella alba 3.1. Cytotoxic and anticancer activity Aliya sheik et al., (2023) evaluated
[10]anticancer activity of methanolic extract of B. alba against HT-29 and HCT-116 colorectal cancer cell lines using XTT.The results showed that the extract had the highest cytotoxicity against HT-29 at a concentration of 50g/ml, inhibiting cell growth by 78.9% in 72h.At 48h, it was discovered that extract in HCT-116 and HT-29 had IC50 values of 51µg/ml and 22µg/ml, respectively with 70% cell growth inhibition.These findings suggested that the extract consisted of a wide-ranging amount of both flavonoid and phenolic compounds which exhibited substantial antioxidant activity.Both colon cancer cell lines experienced a cell cycle arrest at the G0/G1 phase after receiving treatment with this extract.[9]Md.Shihabul Islam et al., (2018) evaluated In Vivo anticancer activity of B. alba leaf and seed extracts against Ehrlich's Ascites Carcinoma (EAC) cell line.In haemocytometic observation, the leaf and seed extracts exhibited about 62.54±2.41%and53.96±2.34%cellgrowth inhibition, respectively, whereas standard drug Bleomycin showed 79.43±1.92%growthinhibition.Morphological alteration under fluorescence microscope showed nuclear condensation and fragmentation which is the sign of apoptosis.[10]

2. Antioxidant activity Aliya sheik et al., (2023) this
[9]dy evaluated and confirmed that the plant Basella alba has good antioxidant activity by observing DPPH, Superoxide, Hydroxyl radical scavenging activities and phosphomolybdate assay.This study showed the DPPH radical scavenging potential of methanolic extract of the plant ranging from 28.24% to 94.81% at different concentrations (20 to 100µg/ml).The IC50 values of the extract in DPPH assay, Superoxide radical scavenging activity, phosphomolybdate assay and hydroxyl radical scavenging activity were found to be 46.6±0.0,47.2±1.2,918.5±0.1 and 380.3±0.9, respectively.[9] [12]57.12±1.11,respectively.The TLC fingerprinting revealed the presence of β-Sitosterol and lupeol in the extract.[12]3.Omowumi O. Adewale et al., (2022)reported that the ethanol extract of B. alba Linn modulates acrylamide induced oxidative stress in Wistar rats.The liver and kidney tissues were processed for the analyses of antioxidant activities.

4. Anti-inflammatory activity Narapusetty Naidu et al., (2017) evaluated
[16]anti-inflammatory activity of ethanolic extract of B. alba in acute and sub-acute model using egg albumin, turpentine oil and formaldehyde as phlogistic agents.The extract showed significant anti-inflammatory activity in a dose dependent manner.The animals were treated with doses 250mg/g and 500mg/kg of extract and Diclofenac sodium at a dose of 10mg/kg was used as a standard drug.The extract (500mg/kg) exhibited maximum anti-inflammatory activity i.e., 46.25%, 44.30%, 46.40% like standard drug Diclofenac 47.02%, 46.50%, 48.57% in egg albumin, turpentine oil and formaldehyde induced methods respectively.[16]

Baskaran et al., (2015) reported
[22] the plant Basella alba reduces hypercholesterolemia in rabbits induced with hypercholesterolemia.The treatment with B. alba extract significantly lowered the levels of total cholesterol, LDL, and triglycerides and increased HDL and antioxidant enzymes levels.The administration of B. alba at 100 and 200 mg/kg decreased TC level by 49 and 54.3%, respectively, LDL level by 45 and 50.1%, respectively, and TG level by 34.9 and 39.7%, respectively.B. alba extract (200mg/kg) reduces TC, LDL and TG levels as effectively as simvastatin.The histopathological examination of aorta showed that B. alba treated rabbits had a significant reduction in aortic plaque and intimal thickening.[19]Helicobacterpyloriusingflowcytometricanalysis.Raw polysaccharides were isolated and 9% of them were identified as AGP (arabinogalactan-protein). Functional assays indicated that fresh extract of the plant inhibited the bacterial adhesion of H. pylori to AGS cells in a dose dependent manner.Best anti-adhesive effect of 67% was observed at 2mg/ml.[27]Biswajitdashetal., (2017) evaluated in-vitro antimicrobial activity of ethanolic extract of stem of B. alba using disc diffusion method and results showed that the extract had significant activity against both gram-positive and gramnegative bacteria and the fungi strains of Candida albicans and Trichophyton rubrum.The maximum antibacterial effect was observed at 100mg/ml i.e., 15.65 and 17.67mm zone of inhibition against Staphylococcus aureus and Escherichia coli respectively.Whereas the standard drug gentamycin showed 29 and 23mm Zone of inhibition respectively at 20mg/ml.The maximum antifungal activity was also observed at 100mg/ml concentration i.e., 20.2 and 15.25mm zone of inhibition and standard drug fluconazole at concentration of 20mg/ml showed 24 and 22mm zone of inhibition against Candida albicans and Trichophyton rubrum respectively.[20]evaluatedantimicrobialactivity of B. alba fruit using agar well diffusion method against eight species of microorganisms.The extract showed significant action against Lactobacillus and Aspergillus fumigatus, no activity was found against Klebsiella and moderate activity was found against other tested organisms.The minimum inhibitory concentration of the extract against bacterial strains was found to be 25mg/ml for Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Lactobacillus, Escherichia coli, Aspergillus niger and Aspergillus fumigates and 50mg/ml for Klebsiella pneumonia.[21]inthisstudy, the ethanolic extract of B. alba on gentamycin induced nephrotoxic wistar albino rats was found to exert nephroprotective effect.It reverses increased serum and urine creatinine, urea, uric acid, protein, gamma-glutamyl transferase (GGT) and malonaldehyde levels and decreased total proteins and free-SH in kidney tissue, which are indicators of oxidative stress of kidney.The experimental results suggested that B. alba extract protected gentamycin induced nephrotoxicity, possibly by enhancing renal antioxidant system.[22] [23].Nguyen et al., (2022) reported antiadhesive activity of polysaccharides from B. alba against3.9.CNS depressant activityAnanda Rajagopal et al (2011) tested and observed that the methanolic and aqueous extracts of dried aerial parts of B. alba (100 and 200 mg/kg) exerted CNS depressant activity in experimental animals.It is evaluated by pentobarbitone induced sleeping time test, open field test and hole cross test in mice.The maximum activity was observed at 120 min in methanolic extract treated animals followed by petroleum ether extract treated animals with 0 number of movements similar to standard drug diazepam.[23]3.

10. Wound healing activity Mohammed et al., (2012) tested
[24]d healing capacity of different gel formulations of aqueous extract of B. alba on male albino rats.In this study, it was observed that 20 days treatment with B. alba leaf extract showed a maximum wound healing capacity.B. alba treated animals were found to epithelize in 23 days while the solvent control and untreated rats epithelize within 35 days and 39 days respectively.So, it was concluded that aqueous extract of B. alba shows significant improvement in burn wound contraction.[24]

3.11. Antiviral activity Cai-Xia Dong et al., (2011) isolated
[30] acidic polysaccharides from aerial parts of B. rubra which exhibited antiviral activity against herpes simplex virus type 2 (HSV-2) by interfering with absorption and penetration of virus to host cells.The most abundant component BRP-4, showed a high therapeutic efficacy in the mouse model infected intravaginally with HSV-2.Orally administered BRP-4 resulted in moderate therapeutic efficacy in the mice infected intranasally with influenza A virus.[30]