A Review of Cordia Species Found in the Caribbean: Cordia Obliqua Willd., Cordia Dichotoma G. Forst. And Cordia Collococca L

ABSTRACT

Members of the Cordia genus possess medicinal properties. There is however limited scientific literature on species within the genus that exists in the Caribbean, namely Cordia obliqua Willd., Cordia dichotoma G. Forst. and Cordia collococca L. This paper provides an overview of these plant species based on their morphology, growth conditions, fruiting season, nutritional and medicinal properties, current processing methods as well as their potential applications in the food and pharmaceutical industries.

KEYWORDS:

• Cordia obliqua Willd
• Cordia collococca L.
• Cordia dichotoma G. Forst
• clammy cherry
• manjack

Introduction

In the Boraginaceae family, there exists a genus of flowering plants with approximately 250 species of tree or shrub sized plants which are native to the Americas but are also found in Asia and Africa (Ferreira Matias et al., 2015). This genus referred to as the Cordia genus, has gained popularity due to its utilization in traditional medicine and as ornamental plants. The Cordia genus has phytochemical, biological and pharmacological properties which has led to their use in ethnopharmacological applications as an antimicrobial or anti-inflammatory agent, anthelmintic, analgesic and diuretic (Ferreira Matias et al., 2015). The Cordia species are also used in treating digestive, respiratory, urogenital, cardiovascular systems and blood disorders (Jamkhande et al., 2013).

Original reports suggested that Cordia collococca L. was the Cordia species found in Barbados (Howard, 1979). It was however recently reported that Cordia obliqua Willd. is the prevalent species there (Centre for Agriculture and Bioscience International, 2019; Sabir and Mahon, 2010). The fruit of C. obliqua Willd. is referred to as “clammy cherry” due to its slimy fleshy pulp (Figure 1); C. dichotoma G. Forst. as fragrant manjack and Indian cherry (Gupta and Gupta, 2015; Jamkhande et al., 2013) whereas Cordia collococca L. is known as red manjack. Some sources classify C. obliqua Willd. and C. dichotoma G. Forst. as synonyms (Patel et al., 2011), while others list them as separate species (Centre for Agriculture and Bioscience International (CABI), 2019). There appears to be two forms of C. obliqua Willd. based on the size of the fruit produced (Gupta and Gupta, 2015). C. collococca L. populates many Caribbean islands including Barbados, Cuba and Jamaica (US National Plant Germplasm System, 2019). This review seeks to highlight the morphological features, nutritional, medicinal properties and current applications of Cordia species found in the Caribbean.

Figure 1. Cordia obliqua Willd. fruits

Plant Morphology and Fruiting Season

C. obliqua Willd. grows in tropical or subtropical climates. The tree is adaptable to a wide variety of soils preferring soils having a light, medium texture (Centre for Agriculture and Bioscience International (CABI), 2019; Mandal, 1997) and is drought resistant (Orwa et al., 2009). C. obliqua Willd. is the most common plant found in the riparian zone (interface between land and a river/stream) of Barbados (Sabir and Mahon, 2010). The plant has short-stalked, white/pink flowers that are bisexual in nature (Gupta and Gupta, 2015; Jamkhande et al., 2013). Pariser (2000) mentions in his book, “Explore Barbados”, that the clammy cherry blooms in April and May after which it produces a round shaped drupe fruit (Gupta and Gupta, 2015). The thick exocarp varies in color as it matures, from green (unripe) to yellow-brown/pink ultimately changing color to black. The mesocarp is pale pink in color and mucilaginous, while the endocarp is hard and stony containing two seeds separated by a stony septum (Gupta and Gupta, 2015). The fruiting season lasts from July to August (Gupta and Gupta, 2015). Fruits may still be observed on trees in Barbados as late as September.

C. dichotoma G. Forst. also grows in tropical and subtropical regions. In Central Java, Indonesia the tree is referred to as the Kendal tree where it is considered a rare species. The tree attains heights of between 3–15 m preferring sandy loam soil with pH 6–6.5 growing best at temperatures between 27–34°C and altitudes above sea level (Rahayu et al., 2017). The tree is perennial and dicotyledonous with bisexual inflorescence flowers that are yellowish white in color and located either in a terminal or axillary position. Leaves are simple having a spiral arrangement (Rahayu et al., 2017).

C. collococca L. is a deciduous tree capable of growing to heights of 35 m. The tree grows across South America and the Caribbean in countries from Cuba to Trinidad. It is a dioecious species preferring sunny weather (Useful Tropical Plants Database, 2019). The plant has a brief synchronous flowering, showcasing its white/cream colored petals at the end of each dry season with flowering occurring between May and October (Opler et al., 1975). The two main fruiting seasons are in May and October with higher yields being obtained in May (Martínez-Echevarría et al., 2017a). Fruits have also been observed in Jamaica as early as September (Useful Tropical Plants Database, 2019). The small round fruit is green when unripe. Upon ripening the fruit is a bright red color and mucilaginous (Opler et al., 1975).

Nutritional Properties

C. obliqua Willd. is a sweet fruit with a total soluble solids (TSS) content of 10.2% (Gupta and Gupta, 2015). The fruit is a source of sugars, protein and minerals (Table 1, Gupta and Gupta, 2015). C. obliqua Willd. methanolic extracts are nontoxic in rats, when injected with no more than 2000 mg/kg (Sivakrishnan, 2018). The entire C. dichotoma G. Forst. tree is edible. The nutritional composition of the leaves and seeds are given in Tables 2 & 3 (Jamkhande et al., 2013). Bromatological studies conducted on C. collococca L. fruits by Martínez-Echevarría et al. (2017a) revealed no significant difference in the data collected for fruits harvested in October 2013 and May 2014 (Table 4). C. collococca L. fruits contain phenolics which impart astringency and unpleasant flavors (Opler et al., 1975; Ulla et al., 2016). Carotenoids, flavonoids, reducing compounds and free amino acids are abundant in both aqueous and alcoholic extracts of fresh C. collococca L. fruits (Martínez-Echevarría et al., 2017b). The presence of trace levels of saponins and tannins were reported in aqueous extracts whereas saponins and fatty compounds were found in alcoholic extracts (Martínez-Echevarría et al., 2017b). Glucose, arabinose, fructose, sucrose and starch were present in abundance (Martínez-Echevarría et al., 2017b). C. collococca L. fruit drink has an ascorbic acid content of 2 mg/30 ml (Martínez-Echevarría et al., 2017a). The low toxicity of active compounds within aqueous and alcoholic extracts, allows for C. collococca L. fruits to be utilized as an unconventional food alternative (Martínez-Echevarría et al., 2017b). Anti-nutritive compounds, such as phytic acid, phytate phosphorus and oxalic acid (355, 100 and 250 mg per 100 g respectively) are present in the fruit (Jamkhande et al., 2013).

Table 1. Nutritional composition of C. obliqua Willd. and C. dichotoma G. Forst. fruits

Nutritional Component	^aC. obliqua Willd Mass/100 g	^bC. dichotoma G. Forst. Mass/g
Total sugars	3.55	18
Reducing sugars	3.41
Non-reducing sugars	0.08
Protein	2.06	35
Fats		37
Ash	2.132
Phosphorus	0.091	0.275
Potassium	1.066
Magnesium	0.067
Calcium	0.062	0.055
Iron	0.005	0.006
Zinc		0.002
Manganese		0.002
Chromium		0.0002
Copper		0.0016/100 g
TSS (fruit pulp)	10.2
Moisture	75	6
Pectin	4.5

^aGupta and Gupta (2015)

^bJamkhande et al. (2013)

Table 2. Nutritional composition of C. dichotoma G. Forst. leaves

^aNutritional component	Percentage composition (%)
Crude protein	12–15
Crude fiber	16–27
Nitrogen free extract	42–53
Ether extract	2–3
Total ash	13–17
Total calcium	2–4
Phosphorus	0.3

^aJamkhande et al. (2013)

Table 3. Nutritional content of C. dichotoma G. Forst. seed kernels

^aNutritional content	Percentage (%)
Moisture	32
Fatty oils	46
Proteins	31

^aJamkhande et al. (2013)

Table 4. Nutritional composition of C. collococca L. fruits

^aNutritional composition	^bPercentage (%)	^cPercentage (%)
Protein	14.26	15.81
Ash	4.95	5.78
Phosphorus	0.19	0.21
Potassium	1.38	1.39
Magnesium	0.38	0.38
Calcium	0.96	0.96
Dry Matter	20.23	31.27
Crude Fiber	21.81	22.90

^aMartínez Echevarría et al. (2017 Martínez Echevarría et al. (2017))

^bOctober 2013

^cMay 2014

Culinary Uses

Gunda pickle is an Indian side dish of which the main ingredient is the exocarp of immature C. obliqua Willd. (gunda). Other ingredients include oil, turmeric powder, salt and homemade achar masala (ground spice mixture made from seeds and powders). The Gujarat (Western India) method involves marinating the fruit with turmeric and salt followed by drying, after which, the achar masala and oil are combined and used as a filling for the seasoned exocarp. This dish may be prepared differently via the Rajasthani (Northern Indian) method in which the fruit is allowed to simmer in seasoned boiling water which softens the fruit and allows for removal of the exocarp. Spices (Rai ka dal, red chili powder, salt, turmeric powder, Hing, Aamchur powder (dry mango powder) and fennel seeds) are then mixed and poured into the exocarp of the gunde. The filled gunde are placed in a jar and heated oil poured over the fruits. Hayes and Laudan (2009) describes pickling as a method by which decomposition of food via microbial growth is prevented by placing foods in acidic solutions. These recipes utilize salt in oil which allows for the production of lactic acid during fermentation. Spices such as turmeric and chili powder, are added for flavor (Hayes and Laudan, 2009).

Medicinal Properties

C. obliqua Willd. plant extracts possess antihyperlipidemic and antioxidant properties with potential application as an oral anti-hypoglycemic agent in the treatment of diabetes (Table 5, Ramakrishnan et al., 2017). The leaves of C. obliqua Willd. are utilized as a medicinal/cooling tea for the treatment of colds, flu, fever or detoxification (Peter, 2012). A formulation developed from C. obliqua Willd. leaf extracts may be used as a contraceptive as it has “strong estrogenic potential” while not presenting the major cardiovascular risks that are usually associated with estrogen (Bhattacharya and Saha, 2013). Methanolic extracts of the seeds and leaves of C. obliqua Willd. exhibit potent antimicrobial activity against oral pathogens such as Gram-positive Streptococcus mitis, S. mutans and S. sanguis and Gram-negative bacteria Pseudomonas gingivalis, Bacillus forsythus and Aggregatibacter actinomycetemcomitans, as compared to the efficacy of standard antibiotics such as Gentamycin, Chloramphenicol, Ciprofloxacin and Erythromycin. The same extract also exhibited antifungal activity against Candida albicans with efficacy comparable to the known antifungal drug, Fluconazole, used for the treatment of yeast infections. C. obliqua Willd. has also been recommended for use as a narrow-spectrum antibiotic against cariogenic pathogens (Sivakrishnan, 2018). C. obliqua Willd. mucilage is considered an expectorant and may be useful for the treatment of lung disease while the raw gum may be used for the treatment of gonorrhea (Choudhary and Pawar, 2014).

Table 5. Medicinal properties of C. obliqua Willd. and C. dichotoma G. Forst

Part of the Plant	Property	Purpose/use
^aCordia obliqua Willd. fruit	Anthelmintic	Eradicate parasites
	Purgative	Increases bowel movements
	Diuretic	Increases urine production
	Expectorant	Treats coughs
	Analgesic	Eases painful joints
^aCordia obliqua Willd. bark		Gripe
^bCordia obliqua Willd. mucilage	Hypotensive agent	Decreases blood pressure
	Respiratory stimulant	Stimulates respiratory rate
^aCordia obliqua Willd. seeds	Anti-inflammatory	Reduce inflammation
	Antimicrobial	Against oral pathogens
^aCordia obliqua Willd. leaves ^cCordia dichotoma G. Forst. leaves ^dCordia dichotoma G. Forst. leaves		Treats ulcers, headaches & reduces fever
	Antimicrobial	Against oral pathogens
	Antifertility	Contraceptive with strong estrogenic potential without cardiovascular risks
^eCordia dichotoma G. Forst. fruit ^eCordia dichotoma G. Forst. bark	Cooling Anthelmintic Diuretic Purgative Expectorant	Fever reduction Eradicate parasites Increases urine production Increases bowel movements Treats coughs Treatment of catarrh

^aGupta and Gupta (2015)

^bAbou-Shaaban et al. (1989)

^cGupta and Kuar (2014)

^dBhattacharya and Saha (2013)

^eDeFillipps and Krupnick (2018)

C. dichotoma G. Forst. methanolic leaf extracts are analgesic, antipyretic and anti-inflammatory (Gupta and Kuar, 2015). Ferreira Matias et al. (2015) reported the presence of luteolin (3′,4′,5,7-tetrahydroxyflavone), apigenin and lupeol in C. dichotoma G. Forst. leaves. Luteolin, is a flavonoid utilized in traditional medicine for its hypertensive, anti-inflammatory and chemo-preventive activity (Avendaño and Menéndez, 2015; Lin et al., 2008). It may also serve as an antioxidant or pro oxidant (Lin et al., 2008). Apigenin (chamomile) acts as an analgesic and sedative (Srivastava et al., 2010) whereas lupeol is an anti-inflammatory agent (Saleem, 2009). Other compounds isolated from dichloromethane extracts of the leaves include β-sitosteryl-3β-glucopyranoside-6ʹ-O-palmitate, nervonyl 4-hydroxy-trans-cinnamate ester and β-sitosterol (Ragasa et al., 2015). The seeds contain alpha-amyrin and 5-dirhamnoside anti-inflammatory agents, betulin, octacosanol, lupeol-3-rhamnoside, beta-sitosterol, beta-sitosterol-3-glucoside, hentricontanol, hentricontane, taxifolin-3, and hesperetin-7-rhamnoside (Gupta and Gupta, 2015; Orwa et al., 2009; Sivakrishnan, 2018). The latter is also found in the roots. Sivakrishnan (2018) corroborated claims of the wound healing activity of the plant using aqueous and methanolic extracts of the leaves and seeds. The natural gums and mucilage of the C. dichotoma G. Forst. fruit contains lupa-20 (29)-ene-3-O-alpha-L-rhamnopyranoside (Gupta and Gupta, 2015).

Two flavonoids, afzelin and quercitrin were identified in C. collococca L. leaf methanolic extracts (Fouseki et al., 2016). Afzelin is a DNA-protective, antioxidant, anti-inflammatory agent also possessing antibacterial properties (Zhou and Nie, 2015). Quercitrin is an antioxidant (Li et al., 2016). Also present in aqueous extracts of C. collococca L. fruits are alkaloids (Martínez-Echevarría et al., 2017b). Lans (2007) mentions the use of C. collococca L. root emollients in the Antilles and Mexico.

Potential Commercial Applications

El-Newary et al. (2015), report that the mucilage of C. obliqua Willd. which swells upon contact with water, is a polysaccharide containing arabinose, galactose, and glucoronic acid, as well as traces of rhamnose. These pentose and hexose units form hemicellulose, which is a component of plant cell walls (Sharma et al., 2018). This compound readily absorbs water and forms a sticky adhesive. Ripe C. obliqua Willd. fruits are used as glue for pasting cardboard and paper sheets (Gupta and Gupta, 2015; Pariser, 2000).

Gum obtained from the fresh and raw fruit mucilage of C. obliqua Willd. tree has been utilized as a release matrix forming material in tablet formulations with Diclofenac, a drug used to treat pain and inflammatory disorders (Gupta and Gupta, 2015). Of the various concentrations utilized, the 2% w/w gum was comparable to the commercial Diclofenac formulation and consequently, the C. obliqua Willd. gum may be considered for use as a sustained release matrix forming material for other drugs as well (Gupta and Gupta, 2015).

A polysaccharide gum was extracted from C. dichotoma G. Forst. fruits utilizing acid precipitation with yields of 86.24% (w/w) (Pawar et al., 2018). The polymer had good flow properties with potential applicability in the pharmaceutical industry (Pawar et al., 2018). Seed kernels of C. dichotoma G. Forst. are high in lipid and protein content making them beneficial as cattle feed (Jamkhande et al., 2013). C. dichotoma G. Forst. also possesses pesticidal activity (Orwa et al., 2009). The fruit extract suppresses larval hatching of Meloidogyne incognita (root-knot nematode), a well-known pest that affects spinach, potato, tomato and lettuce, causing swollen roots, dwarfing and abnormal colors. This worm is widespread in many Caribbean islands (Centre for Agriculture and Bioscience International (CABI), 2019). C. collococca L. fruit are a moderate source of protein for birds, whose eggs and meat are the main source of protein in Cuba (Martínez-Echevarría et al., 2017b). C. collococca L. decoctions may also be used as an insecticide (Martínez-Echevarría et al., 2017b).

Conclusion

Several studies have been conducted on C. obliqua Willd. There is however limited literature available on C. dichotoma G. Forst. and C. collococca L. In the Caribbean these fruits have been utilized in traditional medicine, in teas and as an adhesive. Very little scientific research has been conducted on the fruits grown in the Caribbean region. Most of the reported literature is for fruits grown in India or South America. The fruits are safe for consumption but grossly underexploited. Potential applications include utilization in the food and pharmaceutical industries.