Introduction

Indigenous plants are found in a particular area or region that provides a specific ecosystem comprising climate, moisture, light, and soil conditions. These plants have survived for thousands of years and exhibit specific characteristics (Bean, 2007). Local Thai people have been consuming edible indigenous plants growing in forests, on mountains, and in gardens and backyards for hundreds of years and have accumulated knowledge about their characteristics, taste, flavor, and aroma for consumption as a side dish in cooking and as a folk medicine (Maneenoon et al., 2015). Thailand has a tropical climate which supports a large biodiversity of plants, particularly indigenous edible plants that are important food sources and are rich in carbohydrates, fibers, vitamins, minerals (Suttisansanee et al., 2023), and proteins (Siripongvutikorn et al., 2023b).

Several scientific documents have investigated diverse bioactive constituents and health functions of local plants. Fourteen species of southern Thailand local edible plants, such as Champereia manillana, Lactuca indica, Glochidion perakense, Parkia timoriana, Diplazium esculentum, Portulaca oleracea, Amaranthus caudatus, Gnetum gnemon, Lasia spinosa, Citrus reticulate, Curcuma longa, Oenanthe javanica, Anacardium occidentale, and Alpinia conchigera, were tested as sources of macronutrients, micronutrients, and bioactive compounds, including β-carotene, lutein, polyphenols, cyanidin, peonidin, and anthocyanidins (Kongkachuichai et al., 2015). Twenty-eight edible local plants (Oenanthe javanica, Houttuynia cordata, Gymnema inodorum, Hapaline benthamiana, Aegle marmelos, Antidesma ghaesembilla, Eleutherococcus trifoliatus, Glochidion hirsutum, Glinus oppositifolius, Sphenoclea zeylanica, Basella alba L, Acmella oleracea, Polygonum odoratum, Glochidion sphaerogynum, Ocimum gratissimum, Bauhinia purpurea, Amaranthus lividus, Erythropalum scandens, Ficus geniculata, Caesalpinia mimosoides, Clinacanthus nutans, Clausena excavata, Aspidistra sutepensis, Tiliacora triandra, Amomum sp., Schinus terebinthifolius, Coriandrum sp., and Dregea volubilis) from the north of Thailand recorded antioxidant properties with high caffeic acid, gallic acid, chlorogenic acid (CGA), p-coumaric acid, o-coumaric acid, catechin, ferulic acid, protocatechuic acid (PCA), and quercetin, with C. mimosoides Lam., D. volubilis Benth., A. ghaesembilla, and Houttuynia cordata Thunb showing potential antidiabetic properties (Dedvisitsakul and Watla-Iad, 2022).

In northeast Thailand, 33 species of edible local plants showed antioxidant activity and organoleptic flavors, such as sweetness, spiciness, sourness, and umami (Chantan et al., 2023). Many tribes (Karen and Lawa community) rely on 12 species of wild edible indigenous leafy plants (i.e. Lygodium flexuosum, Acmella paniculata, Clerodendum glandulosum, and Ficus auriculata) as sources of body minerals, particularly magnesium (Punchay et al., 2020). The consumption method of each plant depends on plant type, personal likes, culture, region, circumstances, income, literacy, and facility support as well as local wisdom. For instance, southern Thais do not eat young mango leaves due to their latex, bitter, and astringent taste, compared to the raw materials available in southern region, where are source of durian, mangosteen, coconut, rambutan, and cashew, whereas northern hill tribes prefer leaves of young mango, which is the main crop and is used as the crucial component of salad and soup. It is pointed out that a number of plants are consumed due to village wisdom, availability, or other conditions. In addition, some Thais eat fruits and young leaves of cashew, while others eat only seeds or nuts. Raw cashew seeds are used as an important ingredient for spicy curry and mixed vegetable soup as well as sweet items (Figure 1) found in southern Thailand, but not in other areas, where the plant is not grown.

Figure 1. (A, B) Raw cashew nut and its menus; (C) spicy curry dish; (D) mixed vegetable soup; (E) sweet snacks. Source: the authors.

Consumption of plants has gained momentum globally due to their health benefits, their capacity to combat several non-communicable diseases (NCDs) as well as infectious diseases, such as smallpox, plague, scarlet fever, cholera, typhoid fever, and malaria (Jiang and Wen, 2021). Edible indigenous plants, particularly in Thailand, which is known as the ‘kitchen of the world’, are now receiving increased attention due to their freshness, less chemical usage, and richness in phytochemicals as well as for purpose of food security. Therefore, this review attempts to integrate and illustrate eight indigenous Thai plants, such as G. gnemon var. tenerum (Liang), G. inodorum (Lour) Decne (Chiang-Da), A. lebbeck (L.) Benth (Ta-Khuk), M. suavis Pierre (Pak-Wan-Pa), S. androgynus (L.) (Pak-Wan-Bann), G. wallichianum/G. perakense (Mon-Pu), P. sarmentosum Roxb. (Cha-Plu) and B. alba L. (Pak-Plang), to better understand food culture, biological activity, and health benefits. It is expected that this information will support the possibility of developing edible indigenous plants to become nutraceutical, functional ingredients, and food products.

Edible indigenous plants of Thailand

Gnetum gnemon var. tenerum (Liang)

G. gnemon var. tenerum (Figure 2) is a popular indigenous edible plant of southern Thailand with local names Liang or Miang. Other countries, such as Indonesia, Malaysia, the Philippines, and Australia, have also reported the Gnetum plant but with different sub-species, characteristics, and names, such as Melinjo, Belinjau, and Bago (Anisong et al., 2022). G. gnemon var. tenerum grows as a shrub, 3 m in height with small fruits, and sleek, smooth lanceolate, elliptical, and ovate oblong leaves. G. gnemon var . gnemon is a tree, with bigger fruit, larger seeds, and longer leaves than G. gnemon var. tenerum (Anisong et al., 2022). Four stages of plant leaf growth include (1) tip or apex; with brownish red-full-leaf, small and very soft, (2) young leaf; with brownish red or mixed with light green and soft, (3) Intermediate leaf (pe-slat); with light green to green and soft leaf, and (4) old leaves; dark green and inflexible that cannot be folded without breaking (Siripongvutikorn et al., 2023b). Most people in Thailand consume Liang leaves in stages of tips to intermediate as fresh, cooked, and side dishes. Popular menus are coconut milk curry, stir-fried with egg, and vegetable soup without coconut milk (Figure 3).

Figure 2. Edible parts of Gnetum gnemon var. tenerum include tip, young, and intermediate leaves. Source: the authors.

Figure 3. Stir-fried Liang leaves with (A) egg, and (B) coconut milk curry. Source: the authors.

Recently, many researchers have attempted to develop value-added products to support busy lifestyles, health concerns, and global demand. Siripongvutikorn et al. (2023a) reported using G. gnemon var. tenerum leaves instead of sea algae to make dried seasoning added with shrimp and dried sesame seeds. Results obtained good sensory scores of 7.10±1.24/9 on hedonic scale. The product also provided total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity as 2575.28±103.80 μg gallic acid equivalent (GAE)/g dry weight (DW) and 0.677±0.0063 mg Trolox equivalent (TE)/g DW. Several petty patents recorded in Thailand include crispy baked Liang vegetable (IPC A23B 7/005, 2016), ice-cream milk with Liang (IPC A23L 1/00, 2023), and functional drink powder from Sangyod rice extract with Liang with probiotic (IPC A23L 2/385 and A23L 7/00, 2023) (Department of Intellectual Property, Ministry of Commerce, Thailand, 2024).

The nutritional composition of G. gnemon var. tenerum (intermediate leaves) includes carbohydrates, proteins, fat, and dietary fiber as 65.63±2.63, 25.41±0.68, 2.30±0.10, and 41.27±0.16 g/100 g DW, respectively, with complete essential amino acids, vitamin A, vitamin C, calcium, copper, iron, magnesium, and zinc (Siripongvutikorn et al., 2023b). Suksanga et al. (2023) reported that G. gnemon var. tenerum powder contained TPC, ferric reducing antioxidant power (FRAP), DPPH radical scavenging activity, and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity at 3548.78±346.25, 192.79±18.90, 152.90±7.83, and 767.21±40.66 GAE/g DW, respectively. Chlorophyll and chlorophyllin found in G. gnemon var. tenerum leaves inhibited gluconeogenesis, increased glucose uptake of rat muscle cells via GLUT 4, and decreased non-fasting blood glucose and hemoglobin A1c (HbA1C). However, the antidiabetic and antihyperglycemic mechanisms remained and required further study.

Testing of G. gneom var tenerum leaf extract on the gut model found that short chain fatty acids (SCFAs) produced during fermentation were propionic acid, butyric acid, and acetic acid as 5.369±0.66 mM, 4.698±0.61 mM, and 23.503±4.51 mM, respectively (Anisong et al., 2023). It is well known that SCFAs are linked to health improvement, including anti-inflammatory, anti-obesity, and immunoregulatory activity to protect against cardiovascular, antidiabetic, and neuroprotective conditions (Xiong et al., 2022). Suksanga et al. (2023) studied the acute and sub-chronic toxicity of G. gnemon var. tenerum powder in culture cells and Wistar rats. Results indicated no cytotoxicity based on cell viability higher than 80%. Wistar rats did not show any abnormal symptoms, noxious, and death after oral administration of 2 g/kg b.w. for 14 days during acute toxicity testing. It was observed that Wistar rats treated with 1.47 g/kg Liang leaves powder were 100% survivors and showed no toxic symptoms in both genders during sub-chronic toxicity testing for 90 days. Body weight, organ weight, and growth rate were normal, without significant differences, compared to the control group. Normally leaf plants contain some compounds that interact with various protease enzymes and nutrients leading to enzymes dysfunction and reduction in digestion of nutrients, decreased absorption (Samtiya et al., 2020). Some antinutrients included phytates, tannins, phenolic, oxalates, and hydrocyamic acid and were found in G. africanum and G. buchholzianum (Suzanne et al., 2017; Ekpo et al., 2012). Fresh leaves of G. africanum contained phytase, tannins, phenolics, and oxalates as 240.23±14.25, 298.09±13.70, 507.19±21.53, and 50.10±0.71 mg/100 g DW, respectively. In addition, G. africanum and G. buchholzianum had high protein but antinutrient inhibited protein digestibility that heat cooking can reduce antinutrient and increase protein digestibility (Suzanne et al., 2017). Although G. gnemon var tenerum has not been documented for antinutritional compounds, in particular for phytate, self-awareness and caution of its over consumption must be considered.

Gymnema inodorum (Lour) Decne (Chiang-Da)

G. inodorum (Lour) Decne (Figure 4) is mainly found in south China and southeast Asia, including Thailand, Indonesia, and the Philippines. G. inodorum, a local vegetable of northern Thailand, belongs to the Apocynaceae family with several local names such as Jiang-Da, Chiang-Da, Pak-Kut, Pak-Muan Ki, and Pak-Seng. G. inodorum (Lour) Decne is a woody climbing shrub with green or dark green smooth leaves. The leaf shape is ovate or elliptic, the leaf apex is cuspidate while the leaf base is obtuse (Norkumai et al., 2023). Its flower inflorescence could be white, light-yellow, or yellow-orange as shown in Figure 4. The color of fruit and nib is green. G. inodorum (Lour) Decne has similar characteristics as that of Gymnema sylvestre (Asclepiadaceae) found in central and western India, tropical Africa, and Australia. G. sylvestre is used as a commercial supplement to treat or prevent diabetes and contains gymnemic acid as an important blood glucose level regulator (Tiwari et al., 2014). G. inodorum in Thailand has the potential for more applications and uses. The young G. inodorum (Lour.) Decne Leaves are used for cooking different dishes, such as stir-fried Chaing-Da with egg or other protein sources, Chiang-Da curry soup, Chaing-Da omelet as well as side dishes with chili paste (Figure 5). Petty patents include Chiang-Da with mulberry leaves tea (IPC; A23L 2/39). Thai inventors developed a low-sugar Gymnema jelly gummy prepared from Chaing-Da (Thailand Techshow, 2024). Chaing Mai University (2022) developed Chaing-Da instant curry as a university invention product champion.

Figure 4. (A) Tip, (B) flowers, (C) fruits, and (D) tree of Chiang-Da. Source: the authors.

Figure 5. (A) Stir-fried Chaing-Da with egg, (B) Chiang-Da curry soup, and (C) Chaing-Da instant curry. Source: the authors.

The proximate composition of G. inodorum (Lour) Decne is shown in Tables 1 and 2. Jeytawan et al. (2022) reported that G. indorum contained gymnemic acid in various preparations of its leaves, such as (1) fresh, (2) baked, (3) baked and roasted, (4) dried, (5) dried and roasted, (6) dried with roasted and fermented, (7) dried, roasted, and boiled for 30 s, and (8) dried, roasted, and boiled for 60 s as 19.4±0.1, 102.0±12.2, 78.6±8.6, 64.2±6.4, 97.4±11.5, 125.8±15.7, 57.8±6.6, and 46.0±3.7 µg/g, respectively. Phytochemical compounds of G. inodorum (Lour.) Decne determined by Liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-Q-TOF/MS) included 6-hydroxykaempferol 7-rutinoside, ascorbyl stearate, adenosine, gymnemic acid I, phenethylamine, momordin Ia, saikosaponin L, isoorientin 2”-[feruloyl-(->6)-glucoside], and kaempferol 7-O-glucoside (Jeytawan et al., 2022). The gas chromatography–mass spectrometry (GC-MS) analysis of volatile oil of G. inodorum (Lour.) Decne contained the following 16 compounds: linolenic acid, n-hexadecanoic acid or palmitic acid, methylparaben, 9,12,15-octadecatrienal, beta-monolinolein, phytol, glycerol beta-palmitate, 2,3-dihydrobenzofuran, tetradecanoic acid, stigmasterol, dl-α-tocopherol, octadecanoic acid, γ-tocopherol, olean-12-ene-3,28-diol, 2-methoxy-5-vinylphenol, and squalene (Dunkhunthod et al., 2021). Saponinsat 34.50–81.60 mg/g dry extract was also found in this plant. Srinuanchai et al (2021) reported that extract of G. inodorum leaves contained (3β,16β)-16,28-dihydroxyolean-12-en-3-yl-O-β-D-glucopyranosyl-β-D-glucopyranosiduronic acid (GIA1) or triterpene glycoside, indicating anti-α-amylase and α-glucosidase. G. inodorum improved glucose absorption in intestinal testing by a CaCo₂ cell model (epithelium cell from colon tissue) and increased sodium glucose co-transporter type 1 (SGT1), a transporter protein for moving glucose from the lumen into epithelium cells by sodium ion activation, leading to GIA1 and inhibiting SGT1, thereby reducing glucose uptake. The leaves extract of G. inodorum retarded hypoxia by decreasing free radical (reactive oxygen species [ROS]) production (Surinkaew et al., 2024).

Albizia lebbeck (L.) Benth (Ta-Khuk)

A. lebbeck (L.) Benth is distributed in Asian countries, such as Cambodia, Indonesia, Laos, Malaysia, Vietnam, and Thailand. This deciduous woody tree grows to 20–30-m height. The trunk is brown or gray and chapped lengthwise and crosswise (Figure 6A). The leaves are bipinnate or twice pinnate containing 2–4 pairs on each side, and obtuse in shape (Figure 6B). The flowers are white-yellow (Figure 6C) and the fruits are pods, ruler-shaped or flat (Figure 6D). Young fruit is green-yellow and old fruit is brown in color (Nanthapat, 2010). A. lebbeck is also known as Ta-khuk, Ma-kham-khok, Suk, and Phruek in Thai. The local people mainly consume tips and young leaves. In Thailand, A. lebbeck is used as a side dish after blanching, and in cooked menus, such as Ta-Khuk leaf with grilled frog curry, Ta-Khuk leaf sour curry, Khanom sommanat with Ta-Khuk leaf, and Ta-Khuk leaf salad.

Figure 6. (A) Husk of the trunk, (B) tip and young leaf, (C) flower, and (D) pod of Albizia lebbeck (L.) Benth. Source: the authors.

The edible part (tip and young leaves) of A. lebbeck contains protein, fat, available carbohydrates, ash, and fiber as 28.43, 3.95, 34.81, 9.29, and 23.57 g/100 g DW, respectively. Vitamin C, calcium, phosphorus, magnesium, sodium, potassium, iron, copper, and zinc contents are 695.24, 885.71, 652.38, 295.24, 176.19, 2057.14, 4.05, 1.05 and 4.43 mg/100 g DW, respectively. This plant also contains various bioactive compounds, including α-carotene 5.6±0.4 mg/100 g fresh weight (FW), β-carotene 37.2±5.7 mg/100 g FW, and total carotenoids 42.8±5.6 mg/100 g FW with total polyphenol 383±61 mg GAE/100 g FW (Sridonpai et al., 2022). Sirichai et al. (2022) reported that the tips and young leaves of A. lebbeck contained flavonoids, such as quercetin 61.87±1.83, kaempferol 36.39±3.30, luteolin 134.20±8.00, apigenin 105.11±7.63, and isorhamnetin 8.05±0.27 mg/100 g DW, and TPC as 24.18-28.89 mg GAE/g DW. Antioxidant activities determined by DPPH scavenging, FRAP, and Oxygen Radical Absorbance Capacity (ORAC) assay were 0.052–0.055, 102.53–135.32, and 473.85–516.64 µmol TE/g DW. Carbohydrate enzyme digestion was inhibited by α-amylase and α-glucosidase at 4.80–6.79% and 19.10–25.88%, respectively. Inhibition of carbohydrate digested enzymes of glucose absorption and blood level glucose provided anti-hyperglycemic and antidiabetic effects. However, nonenzymatic processes between reducing sugar and protein or protein glycation can cause diabetes due to changing membrane structure. The final advanced glycation end products (AGEs) generated oxygen free radicals that induced intra-cellular and extra-cellular inflammation causing diabetic complications (Singh et al., 2014). Anti-glycation activities of A. lebbeck were 55.65–60.89% determined by bovine serum albumin (BSA) induced by either sugar (D-glucose) or methylglyoxal (MG) as 30.07–33.57% (Sirichai et al., 2022). Cholinesterase inhibition is related to acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes degrading neurotransmitters. A. lebbeck extract inhibited AChE and BChE activities at 38.10–40.72% and 68.77–74.67%, respectively (Sirichai et al., 2022). Young leaf extracts of A. lebbeck with different solvents included hexane (AHE), mixed solvent (AME), and 95% ethanol (AEE). The AHE and AME extract did not show any toxicity to HMC3 cells (cell variable > 80%) with a concentration of 1–100 µg/mL, while AEE expressed toxicity to cells at 50–100 µg/mL. Oxidative stress and endoplasmic reticulum tension are induced by glutamate, a major excitatory neurotransmitter involved with increasing calpain-1 and caspase-12. Higher calpain-1 and caspase-12 indicate higher endoplasmic reticulum tension. Results showed that AHE reduced the expression of calpain-1 and cleaved caspase-12 more than the control group of HMC3 cells exposed to glutamate (Phoraksa et al., 2023).

Melientha suavis Pierre (Pak-Wan-Pa)

Melientha suavis Pierre (Figure 7) is called Pak-Wan-Pa, where Pa means ‘forest,’ ‘wild’, or ‘jungle’. This plant belongs to the family Opiliaceae. M. suavis Pierre is found in southeast Asian countries, including Malaysia, Cambodia, the Philippines, Vietnam, and Laos (Ruttanaphan et al., 2022) and grows as a wild small deciduous tree with simple and alternate leaves—elliptical- and ovate-shaped. The inflorescent-type flowers are light green in color and grow on the trunk and branches. The young aggregate fruit is green and mature fruit is yellow in color (Thailand Institute of Scientific and Technological Research, 2015). The leaves of M. suavis have a sweet taste. The local people in northern and northeastern areas consume the leaf tip, young leaf, young flowers, and fruit either fresh or cooked. Popular menus of this plant include Pak-Wan-Pa salad, stir-fried Pak-Wan-Pa with egg, Pak-Wan-Pa soup, stir-fried spicy Pak-Wan-Pa, omelet Pak-Wan-Pa, and Pak-Wan-Pa curry. The Thailand Institute of Scientific and Technological Research (2015) created Melientha spicy curry. The extract of M. suavis leaves is used to develop sunscreen with antioxidant properties (Sansomchai et al., 2021). An indigenous plant that shares similar characteristics, except the flower, with M. suavis is Urobotrya siamensis, but this plant is not consumed due to high toxicity (Bunakkharasawat et al., 2019). Up to 15 deaths are reported due to consumption of U. siamensis (Tourdjman et al., 2009) with unidentified poisonous compound. The flower of U. siamensis is raceme type, while the flower of M. suavis is panicle-type, as shown in Figure 8.

Figure 7. Melientha suavis Pierre: (A) tree, (B) tip and young leaves, and (C) fruits. Source: the authors.

Figure 8. Flowers of (A) M. suavis, and (B) U. siamensis. Source: the authors.

Nutritional values of tips and young leaves of M. suavis are shown in Tables 1 and 2. Contents of vitamins and minerals discovered in the fresh tips and young leaves of M. suavis included vitamin C, calcium, phosphorus, magnesium, sodium, potassium, iron, copper, and zinc as 1124.67, 206.90, 583.55, 297.08, 58.36, 1586.21, 7.96, 1.01, and 4.41 mg/100 g DW, respectively (Sridonpai et al., 2022). Bioactive compounds of M. suavis include chrysoeriol, alkaloids, anthraquinone, coumarin, flavonoids, saponins, sterols, terpenoids, and tannins (Charoenchai et al., 2013). Both tips and young leaves contain β-cryptoxanthin, α-carotene, and β-carotene as 3.0±1.0, 4.0±2.2, and 21.0±5.5. Total carotenoids, TPC, and antioxidant activities of tips and young leaves were 28.0±8.7 mg/100 g FW, 292±86 mg GAE/100 g FW, and 10,643±1721 µmol TE/100 g FW, respectively (Sridonpai et al., 2022). Sansomchai et al. (2021) stated that the plant leaf extract exhibited IC₅₀ values determined by ABTS and DPPH assays as 64.17±5.76 µg TE/mL and 6.31±1.73 µg ascorbic acid/mL, respectively, with TPC as 149.87±2.72 mg GAE/g extract and total flavonoid content (TFC) as 51.60±4.12 mg catechin/g extract.

Sauropus androgynus L. (Pak-Wan-Bann)

Sauropus androgynus L., of the Phyllanthaceae family, is cultivated in Asia and Indochina countries, including India, Bangladesh, China, Indonesia, Malaysia, and Thailand. S. androgynus is a shrub with pinnately compound leaves (Figure 9A), ovule- and lance-shaped. The top side of the leaf is dark green and under side light green in color; the flowers are cymose-type (Figure 9B), dark red in color, and look like an umbrella or plate. The fruit (Figures 9B and 9C) is globular-shaped, with a red calyx. Young fruits are light yellow-green and turn light pink when mature. The seed (Figure 10C) is black or white in color and hard (Anju et al., 2022). Local names in Thailand are Ma-Yom-Pa, Kaan-Tong, and Pak-Wan-Tai-Bai. The local people mostly consume its tips, young leaves, and fruits because of sweet taste and mild fragrance. Several menus, such as, soup, curry, stir-fried, and side dishes for chili paste are shown in Figure 10.

Figure 9. (A) Tip and young leaves, (B) flower and fruit, and (C) seeds of Sauropus androgynus (L.). Source: the authors.

Figure 10. Popular menus cooked from tips and young leaves of S. androgynus (L.): (A) stir fried, (B) coconut milk soup, and (C) spicy salad. Source: the authors.

Nutritional values of S. androgynus (L.) leaves comprise 3.4–29.2% DW protein, 0.5–54.5% DW carbohydrates, 0.6–4.6% DW fat, 1.2–36.0% DW fiber, and 1.4–12.9% DW ash (Khoo et al., 2015). Purba et al. (2022) found that S. androgynus contained vitamin C as 5.77–5.78 mg/g DW, total tannins as 0.04 mg/g DW, total flavonoids as 2.3–2.36 mg/g DW (catechin, rutin, myricetin, quercetin, apigenin, and kaempferol), total cinnamic acid as 0.18–0.20 mg/g DW (caffeic acid, syringic acid, p-coumaric acid, sinapic acid, and ferulic acid) and total essential oil as 0.32–0.33 mg/g DW. DPPH^•, ^•NO, and O₂^•- scavenging in terms of IC₅₀ values were 13.14±0.055, 55.02±1.338, and 25.31±0.886 mg/mL, respectively. S. androgynus exhibited IC₅₀ values for inhibition activity, hemoglobin oxidation, and lipid oxidation as 11.96±0.011, 13.54±0.012, and 5.940±0.005 mg/mL, respectively. Moreover, the plant extract inhibited α-glucosidase at 9.83±0.032 mg/mL. For antimicrobial properties, S. androgynus exhibited clear zones of Staphylococcus aureus and Klebsiella pneumoniae at 11.33±0.5774 mm and 13.66±0.577 mm, respectively (Paul and Anto, 2011).

Some research studies mentioned the side effects of S. androgynus consumption, with the contained papaverine causing bronchiolitis obliterans syndrome. Hsiue et al. (1998) reported that 49 patients who consumed 36–186 g/day S. androgynus for 12–150 days were associated with dyspnea. However, Ou et al. (2013) who conducted study after 15 years of Hsiue et al.’s (1998) findings, described 16 of the 49 patients who survived and could be contacted reported that none had a significant decline in lung functioning.

Glochidion wallichianum/Glochidion perakense (Mon-Pu)

Lemmens and Wulijarni-Soetjipto (1991) reported that G. wallichianum had different synonyms, such as Glochidion glomerulatum (Miq.) Boerl, while Glochidion perakense was a synonym of Glochidion sumatranum. In addition, the information stated that G. perakense and G. wallichianum were not from the same species. On the other hand, Yoon and Sakdiset, (2020) stated that G. wallichianum is a synonym of G. perakense. It is reported that G. wallichianum is referred by the local name of Mon-Pu (Chumsri et al., 2022; Junsathian et al., 2018), while some specified G. perakense as Mon-Pu (Kongkachuichai et al., 2015). However, Supattra (2022) reported two typical tips or young leaves of Mon-Pu in Thailand that are red type (G. perakense) and white or green type (G. wallichianum), as shown in Figures 11 and 12. Interview data and market survey found that the light green tip type had a lesser bitter taste compared to the red tip, but variation of bitterness in each tip type was not consistent and could be due to various reasons, such as area of planting, light intensity, fertilizer, rainfall, and co-planting. No scientific data can explain the differences and typical characteristics of these species and further investigations are required. Mon-Pu is an indigenous plant of southern Thailand with different local names such as Mon-Pu, Phung-Moo, and Yord-thaea. Mon-Pu belongs to the Euphorbiaceous family and is found in Malaysia, Indonesia, northern Australia, and south China. Mon-Pu is a shrub or tree that grows to 8-m height, glossy, with ovate-oblong to ovate-lanceolate or elliptic-lanceolate leaves with acute or round base, brownish-green or green in color. The flower inflorescence is light green, separated between pistillate and stamen with six sepals and three stamens. The fruits are round, green when young and red when old with soft and short hair cover. The seeds are hemispheric (Figure 13; Chheang et al., 2022; Sandhya et al., 2010). Local Thais consume young leaves as a side dish of vermicelli with spicy curry (Khanom-Jeen), chili paste, and curry. The plant leaves can be cooked in different menus, including stir-fried with egg and spicy salad, as shown in Figure 14.

Figure 11. (A) Typical red type of tree; (B) tip and young leaves; (C) typical light green type of the tree; and (D) tip and young leaves of Glochidion plant. Source: the authors.

Figure 12. Characteristics of leaf and branches of the light green and red type of Glochidion plant. Source: the authors.

Figure 13. Characteristics of (A) tip, (B) edible leaves stage, (C) young fruits, and (D) seeds of Glochidion plant. Source: the authors.

Figure 14. Popular cooked dishes or served with Glochidion plant leaves: (A) chili shrimp paste dip and (B) stir-fried with eggs. Source: the authors.

Kongkachuichai et al. (2015) reported that Mon-Pu (G. perakense/G. wallichanum) contained various nutritious compounds, such as vitamin C, vitamin E, calcium, phosphorus, potassium, magnesium, and iron (Tables 1 and 2). In terms of biological activity, Mon-Pu leaves are antioxidants due to β-carotene (1.41±0.017 mg/100 g FW), lutein (3.43±0.094 mg/100 g FW), cyanidin (13.29±0.85 mg/100 g FW), gallic acid (26.75 mg/100 g), epicatechin gallate (ECG; 0.25 mg/100 g), and apigenin (0.039 mg/100 g); it also recorded the highest antioxidant activity based on hydrophilic (H-ORAC) and FRAP assay among 15 Thai indigenous vegetables, including A. occidentale, O. javanica, G. gnemon, and P. timoriana (Kongkachuichai et al., 2015). This plant also showed TPC and TFC as 248.33±7.72 mg GAE /g crude extract and 30.34±1.14 mg quercetin equivalent/g crude extract, respectively, with DPPH scavenging activity of 44.77±7.00 mmol of TE/100 g crude extract and FRAP being 364.12±32.28 mmol of Fe (II)/100 g crude extract (Junsathian et al., 2018). The plant extracts yielded antimicrobial properties determined by disc diffusion and tested with inhibition zones of Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa at 16 mm, 15 mm, 10 mm, and 13 mm, respectively. Results indicated minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MIBs) as 0.78 and 25 (S. aureus), <1.56 and 25 (B. subtilis), 3.12 and 50 (E. coli), and 3.12 and 25 (P. aeruginosa) (Junsathian et al., 2022). The antimicrobial activity of Mon-Pu ranged broadly for both Gram-positive and Gram-negative pathogenic bacteria. Interestingly, the plant extract also provided strong antioxidant activity by inhibiting Aβ 42 aggregate formation. Therefore, Mon-Pu extract may be an alternative treatment to prevent or slow down dementia. The extract also promoted the viability of cells treated with hydrogen peroxide (H₂O₂), demonstrating high potential to reduce oxidative stress (Junsathian et al., 2018). Mon-Pu leaf extract improved rat liver damaged from ethanol (alcohol) via reduced secretion of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) functioning. Furthermore, the plant extract also decreased malondialdehyde (MDA) (the product of lipid peroxidation), referring to oxidative stress in cells. Results showed that the hepatic MDA level of rat fed with ethanol followed by Mon-Pu treatment was lower than fed with ethanol alone, and lessening in damaged tissue and reduction of triglycerides accumulation in the liver were also noticed (Samuhasaneeto et al., 2022). Results indicated that adding Mon-Pu extract to rice starch led to improved retarding of starch digestibility, compared to brown rice starch because of high polyphenol content in the plant extract (Chumsri et al., 2022). Fish sausage products with added Mon-Pu leaf extract also yielded lower values of lipid and protein oxidation during processing and storage, compared to the control (Wongnen et al., 2022).

Piper sarmentosum Roxb. (Cha-Plu)

Piper sarmentosum Roxb. belongs to the Piperaceae family and is distributed in Malaysia, Thailand, Indonesia, Vietnam, China, the Philippines, and Myanmar (Akmal et al., 2023; Ware et al., 2023). In Thailand, P. sarmentosum is called by its local names such as Cha-Plu (central regions), Nom-wa (southern regions), Pak-pu-na, Plu-ling, and Pak-plu-nok (northern regions), and Pak-nang-leard, Pak-ei-leard, and Pak-care (northeast regions). P. sarmentosum is a wiggle plant with a height of 20 cm. The leaves are light-green to dark-green in color, glossy and heart-shaped. The fruits are cylindrical and oval-shaped, thick and green with a sweet taste. The flowers are separated by gender, inflorescent type, oval-shaped and white as shown in Figure 15 (Mathew et al., 2004; Othman et al., 2022). Cha-plu is served as a side dish and cooked in coconut milk curry, spicy green mussel in coconut milk curry, and Miangkham or royal leaf wrap appetizer (Figure 16).

Figure 15. Characteristics of Cha-Pu include (A) wiggling and tipping leaves, (B) inflorescence, and (C) fruit. Source: the authors.

Figure 16. Popular menu of using Cha-Pu as a cooked ingredient or eaten as fresh leaves as a wrapping or side dish. (A) Spicy green mussel in coconut milk curry, and (B) Miangkham. Source: the authors.

Ware et al. (2023) reported that dried leaves of P. sarmentosum contained 31 compounds comprising 2 flavonoids, 12 phenolics, 2 amides, 8 alkaloids, 2 terpenes, 3 lignans, and a sterol. Abundant biological compounds of this plant include caffeic acid, p-coumaric acid, ascorbic acid, gallic acid, catechin, syringic acid, rutin, sinapic acid, ferulic acid, cinnamic acid, myricetin, quercetin, apigenin, kaempferol, eugenol, β-sitosterol, naringenin, sarmentine, sesamin, 1-piperettyl pyrrolidine and pellitorine, quercetin, hesperidin, pipertiol, malvidin, and naringenin (Akmal et al., 2023; Azelan et al., 2022; Purba et al., 2021). The highest component found in the plant leaf extract was 4H-pyran-4-one,2,3-dihydro-3,5-dihydroxy-6-methyl, followed by octanamide, N,N-dimethyl, and 3-(4-methoxyphenyl) propionic acid (Syed Ab Rahman et al., 2014). P. sarmentosum leaf provided TPC as 10.98 mg GAE/g DW, TFC as 48.57 mg GAE/g DW, and DPPH scavenging activity as 46.84% (Wongsa et al., 2012; Ugusman et al., 2012). Chaplu leaves contained oxalates as 7026.6±76.9 mg/100 g DW (Juajun et al., 2012) and it caused a lower minerals (especially calcium) absorption and induced kidney stone (Petroski and Minich., 2020). However, antihyperglycemic properties of P. sarmentosum were reported and linked to anti-α-glucosidase activities but not to anti-α-amylase (Ugusman et al., 2012).

By contrast, Sallehuddin et al. (2020) reported that P. sarmentosum did not show anti-α-glucosidase activity. However, P. sarmentosum reduced fasting blood glucose levels and increased insulin levels in diabetic mice (Luangpirom et al., 2014). Diabetic Sprague-Dawley rats treated with plant extract displayed lower fasting blood glucose levels at 0.0232 mmol/mL, compared to non-treated groups at 231 mmol/L (p < 0.05). The tested animals had higher body weight than the non-treated group of animals (p < 0.05). They showed recovered cardiovascular system with improved nucleic size, and shape of cardiomyocytes as normal, reduced unregulated arrangements of myofibrils in the cardiac muscle, less dysfunctioning of mitochondria in the cardiac tissues, less endothelial injury, and decreased proliferation of the aorta tissue in the aortic wall, compared to the diabetic rat nontreated group (Thent et al., 2012).

P. sarmentosum also improved liver tissue and recovered hepatocytes to normal size, reduced abnormal nucleic of hepatocytes, decreased necrotic cell (uncontrolled death cell occurs by cell injury resulting from the environment), and relieved bleeding from sinusoids, with increased liver weight (Thent and Das, 2015). The aqueous extract was given to spontaneous hypertensive rats (SHRs). Results showed lower systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) than the nontreated rats (p < 0.05), with higher nitric oxide (NO) and reduced MDA levels (Zainudin et al., 2015). Nitric oxide is released into vascular endothelium and helps to maintain vascular homeostasis, vasodilatation, proliferation of cell growth and regulation of endothelial function, which play a key role in blood flow and maintaining normal blood pressure (Zhu et al., 2016). MDA is used as a biomarker of oxidative stress. Hypertensive patients have higher MDA levels than normal humans (Cristina et al., 2007). NO is obtained from foods containing nitrate and/or nitrates, which are precursors of NO synthesis pathway. In addition, many leafy vegetables contain nitrates through roots absorption from soil into the xylem and sent to leaves for growth and development process, including regulation of biosynthesis, signaling, hormone, and transport (Vega et al., 2019).

Fauzy et al. (2019) also reported a similar result for SHRs treated with P. sarmentosum aqueous extract, which reduced SBP, DBP, and MAP and promoted NO. However, the aqueous extract did not decrease serum lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) in SHRs (Zainudin, et al., 2015). Higher levels of LDH are linked to endothelial damage, while higher levels of CPK impacted shriveled vascular and promoted risk of hypertension (Brewster et al., 2019; Cai et al., 2023). Sprague Dawley stress-induced rats treated with P. sarmentosum showed reduced stomach lesions and interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) in gastric tissues where cytokines were released as an acute inflammatory response (Akmal et al., 2023).

Moreover, the plant extract showed potential against bacterial and fungal growth. The leaf extract reduced mycelial growth of Rhizoctonia solani and Bipolaris oryzae by 51.77% and 41.45%, respectively. The clear zone of Xanthomonas oryzae pv. oryzae at 6.8 mm could be due to the main bioactive compounds isolated from P. sarmentosum essential oil, including myristicin, sarmentine, brachystamide B, brachyamide B, and piperonal (Chanprapai et al., 2017). Kadukoside, isoasarone, trans-asarone, piperolactam A, dehydroformouregine, and 5-hydroxy-7,40-dimethoxy flavone of P. sarmentosum showed antimicrobial activity against Septoria triciti, Botrytis cinerea, and Phytophthora infestans (Ware et al., 2023).

The anti-obesity property of P. sarmentosum extract was reported by Kumar et al. (2021) in studies on Wistar rats. Results showed that the extract exhibited a lower body weight and fat mass, compared to obesity Wistar rats fed with fructose and olive oil (p < 0.05). P. sarmentosum also improved leptin level, adiponectin level, and 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase level, compared to obese Wistar rats. The rats fed with fructose and olive oil showed excessive growth of adipocytesin adipose tissue, while adipocytes of Wistar rats treated with the plant extract were smaller in size. The extract of P. sarmentosum improved lipid profiles by increasing HDL level and decreasing LDL, triglycerides, and total cholesterol (Fadze et al., 2018).

Basella alba L. (Pak-Plang-Khaw) and Basella alba L. var. Rubra (Pak-Plang-Dang)

Basella alba L. and Basella alba L. var Rubra or Basella rubra (Figure 17) belong to the Basellaceae family, with common names as Malabar Spanish, Indian spinach, Ceylon spinach, climbing spinach, East-Indian spinach, Chinese spinach, cyclone spinach, and vine spinach. They are cultivated in Indonesia, India, Malaysia, the Philippines, tropical Africa and tropical South America (Deshmukh and Gaikwad, 2014). In Thailand, the plant is called Pak-Plang (common name), Pak-Plang-Khaw (green stem type), Pak-Plang-Dang (red-purple stem type), and Phak-Pang (northern region). This climbing vine plant has simple, cordate-ovate-shaped, green and mucilaginous leaves. The stem is green (Basella alba L) or purplish (var. Rubra), branched and succulent. The flower is spiked and bisexual, with white-pink blossom in leaf axils. The fruit is oblong-shaped, small 7–8 mm in size, and dark violet in color. The seeds are black and rough (Figure 18). Mostly, Thai people consume tips and young leaf stems and young flowers as side dishes of spicy paste and curry as well as cooked items, such as salad, sour soup, and stir-fried with oyster sauce or eggs (Figure 19). The ripped seed coat is used as a natural colorant (betalanin) (Paseephol et al., 2012) in snacks or desserts, such as sweet-noodle in coconut milk syrup (Sarim), floral rice cake (Kanom-nam-dok-mai), and rice balls in coconut milk (Bua-loi) as shown in Figure 20.

Figure 17. (A) Pak-Plang-Khaw; (B) Pak-Plang-Dang. Source: the authors.

Figure 18. Pak-Plang-Khaw: (A) Tip and young leaves, (B) flower, and (C) fruits. Pak-Plang-Dang: (D) Tip and young leaves, (E) flower, and (F) fruits. Source: the authors.

Figure 19. Popular dishes of Pak-Plang-Khaw: (A) Stir-fired with oyster sauce; (B) soup with minced meat; and (C) deep-fried plant leaves with salad style. Source: the authors.

Figure 20. Natural colorant from the Pak-Plang-Dang seeds and its application in Thai desserts. Source: the authors.

The nutrition contents of Basella alba L. and B. rubra leaves are shown in Tables 1 and 2 (Kumar et al., 2015). Fatty acid content of both species consisted of monounsaturated fatty acids (MUFAs) as 1.19–1.24% and polyunsaturated fatty acids (PUFAs) as 72.5–73.8%, including linoleic acid and α-linoleic acid, which promote health benefits (Adesina et al., 2017). Vitamins and minerals included niacin, ascorbic acid, iron, zinc, copper, sodium, potassium, magnesium, and calcium as 0.5±0.01, 68±5, 4.7±0.05, 0.2±0.02, 0.04±0.00, 19±1, 517±4.4, 66±1, and 32±3 mg/100 g FW. B. alba and B. rubra had chlorophyll a and b and β-carotene as 31–92, 15–47, and 1.9–5 mg/100 g FW, respectively (Kumar et al., 2015).

The phytochemical compounds of B. alba are saponins, diterpenes, phenols, tannins, flavonoids, cardiac glycosides, steroids (β-sitosterol and stigmasterol), phytosterols, and alkaloids (β-cyanine) (Bose et al., 2023; Tongco et al., 2015). Main polyphenolic compounds in B. alba and B. rubra are 4-hydroxyl benzaldehyde, gallic acid, p-coumaric acid, salicylic acid, caffeic acid, ferulic acid, trans-cinnamic acid, galloyl shikimic acid, diosmetin, kaempferol, rutin, and acacetin (Bose et al., 2023; Kumar et al., 2018). Betacyanin pigments in B. rubra are hydroxycinnamic acid, gandolin, globosin, basellin, and gomphrenin. The leaf extract expressed antioxidant properties determined by ABTS, FRAP, ORAC, and DPPH as 288.2 mg/L (EC₅₀), 0.061 mmol TE/g DW, 0.26 mmol TE/g DW, and 1009 mg/L (EC₅₀), respectively (Kozioł et al., 2024).

B. alba plants expressed the IC₅₀ value of DPPH, H₂O₂, •OH, and phosphomolybdate scavenging activities as 46.6±0.0, 47.2±1.2, 380.3±0.9, and 918.5±0.1 μg/mL, respectively (Sheik et al., 2023). B. alba leaves showed DPPH scavenging as 112.96±4.87 μg/mL (Islam et al., 2018). When B. alba leaf extract was fed to rats, the results indicated a decrease in stomach ulcers via reduced total acidity value, increased pH of gastric juice, and decreased ulcer index. Reduced ulcer areas and smaller damage in the epithelium were also noticed (Kumar et al., 2012).

Isovitexin obtained from B. rubra exhibited potent activity against human colon cancer cell lines (HT-29) with an IC₅₀ value of 0.0294 mg/mL. Characteristics of death of HT-29 cells included group cell, contraction cell, curling cell, and fragmentation of cells. The mechanism of isovitexin was enchantment enzyme of apoptosis in HT-29 cells, such as caspase-3 and procaspase-3, and inhibition of apoptotic inhibitor (Bcl-2 protein) (Kilari et al., 2018). Sheik et al. (2023) reported that B. alba extract showed antiproliferation of human colon cancer cells in HT-29 and HCT-116 cell lines, with suppression of cyclin D and cyclin-dependent kinases-4 (Cdk4) in colon cancer cells, leading to retarded cell growth and proliferation. B. alba showed antidiabetic properties in diabetic rats after treatment with leaf extract (200 mg/kg b.w.) by reducing fasting blood glucose levels, compared to the control and diabetic rats without extract (p < 0.05) (Bamidele et al., 2015).

Interestingly, ripped seeds with red-purple color of B. rubra indicated antioxidant effect because of betacyanin pigment. The antioxidant activity of B. alba fruits because of IC₅₀ of DPPH and H₂O₂ scavenging were 21.55–34.37 and 27.99–46.57 μg/mL, respectively (Ashaduzzaman Nur et al., 2023). However, cyanogenic glycosides in the plant seeds exhibit toxicity for animals and humans. The leaves of B. alba L. contained 5.04±0.20 mg HCN/kg (Uhegbu et al., 2011), which was higher than the World Health Organization’s (WHO, 2011) reference dose level of 0.09 mg/kg b.w.. Some studies have reported that Basella alba L. leaves extract could be used as an antidote for cyanide poisoning in Wistar rat model (Dada et al., 2020). However, reduction of cyanogenic compounds to a safe level could be achieved by processing, that is, by drying, soaking, boiling, fermentation, steaming, baking, and frying (Nambisan., 2011). Biological activities of eight indigenous plants are summarized in Table 3.

Local foods

Edible indigenous plants of Thailand—Liang, Chiang-Da, Ta-Khuk, Pak-Wan-Pa, Pak-Wan-Bann, Horapha, Mon-Pu, Cha-Plu, and Pak-Plang—are consumed as fresh and/or in cooked forms. However, cooking details and processes could be different, as shown in Table 4.

Some health benefits of the above-mentioned indigenous plants are purposed, and their weak points are also embedded, such as less scientific documents, periodic raw materials, safety protocol, and narrow/wide utilization. However, it was found that some indigenous plants were selected and grown for the purpose of commercialization after publishing of research papers. For instance, Chiang-Da is now considerably planted in Thailand for not only fresh consumption but also for nutraceutical and functional products used for controlling blood sugar. Laing leaves are intensively grown in the country for their umami taste and unique flavor as well as health benefits (Siripongvutikorn et al., 2023., Suksanga et al., 2023).

Regardless of how raw materials were investigated, the dishes produced are not well-studied, maybe due to food complications and less systematic financial support. Therefore, only a few scientific data dealing with dishes were addressed; for example, spicy coconut milk curry with Chaplu leaves revealed antioxidant and antimutagenicity activity (Tangkanakul et al., 2011). Chiang Da curry with dried fish contained protein, fat, carbohydrate, dietary fiber, and ash as 6.48, 1.41, 2.36, 2.40, and 2.61 g/100 g edible portion, while Na, Ca, P, Fe, Zn, and Cu were 663.88, 102.58, 231.09, 1.34, 0.80, and 0.23 mg/100 g edible portion (Tangkanakul et al., 2006). Spicy curry with Pak-Wan-Bann contained proteins, fat, carbohydrate, dietary fiber, and ash as 4.19, 0.91, 3.86, 1.20 and 1.38 g/100 g edible portion, while Na, Ca, P, Fe, Zn, and Cu were 386, 70.51, 128.24, 0.90, 0.90, and 0.29 mg/100 g edible portion, respectively (Tangkanakul et al., 2006).

Owing to high acceptability, indigenous plants are a source of biological activities and health functions. In addition, cooking process, used ingredients, and seasonings could have both positive and negative effects on phytochemicals as well as health.

In Thailand, the most commonly used ingredient is fermented shrimp paste (Kapi). Intensive review indicated that Kapi contained proteins, fat, fiber, and carbohydrate as 27.0–29.9, 2.1–2.9, 1.2–1.3, and 16.5–18.4 g/100 g, respectively. In addition, Kapi showed antioxidant activity and angiotensin I-converting enzyme (ACE) inhibitory activity (Kleekayai et al., 2015). Besides this, major herbals and spices, such as garlic, shallot, kaffir lime leaves, galangal, ginger, holy basil, and chili are good source of several bioactive compounds and pharmacological properties (Buathong and Duansrisai., 2023).

Moreover, coconut milk (Kathi), which is an essential ingredient of Thai spicy curry or soup contains proteins, fat, and carbohydrate as 4.13–5.83%, 1.83–3.11%, and 1.94–2.21%, respectively. Phenolic compounds discovered in coconut milk included gallic acid, chlorogenic acid, parahydroxybezoic acid, caffeic acid, vanillic acid, syringic acid, and ferulic acid related to antioxidant activity by reducing oxidative stress in cells. However, rats fed with coconut milk showed an increment of total cholesterol and triglycerides, compared to baseline, but not significantly different from the control group (Karunasiri et al., 2020). Indigenous plants and other ingredients support health benefits, however, amount of overdose of seasoning particularly sugar, table salt, monosodium glutamate, fish sauce, soy source as well as oyster sauce may dilute the positive effects such as amount of high sugar in food risk to hyperglycemia and diabetic disease for long term, and high salt is risk to hypertensive.

Conclusion

Thai people have been consuming edible indigenous plants as side dishes and in cooked forms as well as for folk medicine purposes since ancient times. Several edible indigenous plants of Thailand contain high nutrients and various bioactive compounds, such as vitamins, minerals, fiber, phenolics, flavonoids, anthocyanidins, carotenoids, and triterpenes, which have antidiabetic, antibacterial, and anti-inflammatory properties and protect neurotransmitters. Eight Thai edible local plants displayed good health benefits with no negative health issues. Antioxidant, antidiabetic, and antimicrobial properties are reported for G. gnemon, G. inodorum, A. lebbeck, P. sarmentosum, S. androgynus and B. alba. Antihypertensive properties are displayed in the case of A. lebbeck and P. sarmentosum. G. wallichianum and P. sarmentosum were related to reduced lipids accumulation and anti-obesity. B. alba showed a strong anticancer activity. However, a research lacuna exists for M. suavis Pierre because of scant documented health research. Moreover, the eight selected plants are not grown commercially due to the lack of systematic records and intensive research. Future scientific studies should concentrate on health functions using animal models and clinical trials to enhance the utilization and application of indigenous plants for the purpose of local foods and related global products.