Yield, Proximate Composition, and Phytochemical Screening ...

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Yield, Proximate Composition, and Phytochemical Screening of “Lagikway,” Abelmoschus manihot (L.) Medik.

Rodel G. Maghirang, Claudette D. Oraye*, and John Marty C. Mateo

Institute of Plant Breeding, College of Agriculture and Food Science University of the Philippines Los Baños, College 4031 Laguna, Philippines

“Lagikway” is an underutilized vegetable in the Philippines. One of the reasons for its low utilization is the lack of information in terms of production and nutritional quality under Philippine conditions. Hence, yield trial and nutritional quality evaluation were conducted from June 2017 to February 2018 involving three lagikway entries – including RXII 13-003, RXII 13-019, and Lag 152649. The effect of blanching on the phytochemicals of leaves for consumption was also determined. Lagikway rooted cuttings were transplanted in 5 m x 1 m plots with 50 cm x 50 cm distance, and the experiment was carried out in a randomized complete block design (RCBD) with four replications. Young leaves and shoots considered for consumption were harvested 1 mo after transplanting (MAT) and continued at 2-wk intervals. Data revealed that potential yield is at 24.5 tons/ha for RXII 13-003, 21.36 tons/ha for RXII 13-019, and 21.94 tons/ha for Lag 152649. For proximate analysis, the moisture content is highest in RXII 13-019, the fat content is highest in RXII 13-003, and the protein content and the nitrogen-free extract are highest in Lag 152649. Ash and fiber content were the same from all the three lagikway accessions. Significant differences were also observed on the different lagikway accessions in terms of phytochemicals and antioxidant activity, and blanching had greatly affected these parameters. Lag 152649 had the highest phenolics, flavonoids, tannins, and radical scavenging activity (RSA). Hence, Lag 152649 will be recommended for mass propagation and distribution, which will eventually lead to further promotion and utilization of this underutilized vegetable.

Keywords: Abelmoschus manihot, blanching, “lagikway,” nutritional quality, yield

*Corresponding Author: [email protected]

INTRODUCTIONAbelmoschus manihot (L.) Medik. is widely cultivated in Melanesia and Eastern Indonesia but not much in the Philippines, Malaysia, and other parts of tropical Asia (Preston 1998). In areas where it is widely cultivated, this plant is also used as a traditional medicine – in treating jaundice, chronic and acute hepatitis, kidney disease, ulcers, burns, and dysmenorrhea (Pan et al. 2017). Following these claims, studies have been made by

researchers to confirm the efficacy and nutritional quality of this plant (Li et al. 2017; Shi et al. 2019).

This plant – commonly known as sunset muskmallow, “gedi,” and “aibika” – has vernacular names such as “lagikway,” “likway,” “galikway,” “gikway,” “barakue,” and “nating saluyot” from different regions in the Philippines. It is usually grown in home gardens and some are found growing on the roadsides in Quezon, Laguna, and in some parts of Bicol Region, Visayas, and Mindanao. Young leaves and shoots of lagikway are used in several Filipino dishes such as “sinigang,” “tinola,” and

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“pinangat” and “ginataan.” Leaves are also used to thicken soups and mixed in salads (Maghirang et al. 2018).

Lagikway is considered an underutilized vegetable in the country despite its health benefits and its potential to be integrated into the cropping system. Some reasons for its low utilization include the lack of information on its nutritional quality and yield under Philippine conditions. Previous studies were done on other countries using different accessions but not on accessions collected from the Philippines. Also, there is no recommended variety of lagikway in the country, although there are apparent regional preferences based on leaf shape and taste. This study then aims to determine the yield and nutritional quality of three accessions of lagikway, which will serve as a basis for variety recommendation that can help in increasing the utilization and promotion of this vegetable in the Philippines. This will be the first report on yield evaluation and one of the very few reports on nutritional quality evaluation of three different accessions of lagikway in the Philippines – including the effect of blanching on the functional properties of lagikway.

MATERIALS AND METHODS

Yield Trial of LagikwayLagikway leaf yield trial of three lagikway accessions (RXII 13-003, RXII 13-019, and Lag 152649; see Figure 1) was conducted at the Institute of Plant Breeding, College of Agriculture and Food Science, University of the Philippines Los Baños (14°9’16” N, 121°15’42” E; 20-m elevation) from June 2017 to February 2018. RXII 13-003 was collected from Glan in Sarangani, RXII 13-019 from Tupi in South Cotabato, and Lag 152649 from Sariaya in Quezon. Lagikway cuttings, about 30 cm in length, were rooted in 3.5 in x 3.5 in x 7 in seedling bags for 2 mo prior to transplanting in the field in 5 m x 1 m plots with a planting distance of 50 cm x 50

cm. The experiment was carried out in an RCBD with four replications. Basal application of vermicompost at 50 g/hill was done prior to transplanting, and side-dressing was done every month. Irrigation was only done as needed. Data gathering started 1 mo from transplanting and continued at 2-wk intervals up to 7.5 MAT. Shoots considered for consumption (i.e. tender and easily snaps off with the fingers) were harvested from each of the plants.

Meteorological records for rainfall, relative humidity, wind speed, and temperature during the growing season were obtained from the University of the Philippines Los Baños–National Agromet Station (Table 1).

Proximate AnalysisMoisture, crude fat, crude fiber, and ash contents were determined using AOAC (1980) methods. Crude protein content was quantified using the method of Nkonge and Balance (1982). In detail, approximately 50 mg of dried powdered sample was placed into a 30-mL digestion flask containing 0.50 g selenium catalyst and 2.0 mL concentrated H2SO4. The mixture was digested for 30 min or until the solution becomes clear. The container was cooled to room temperature and the digest was transferred into a 10-mL volumetric flask and was diluted to volume. A 10-µL aliquot of the solution was placed in an 18 mm x 150 mm test tube and was added with 1.5 mL working buffer (mixture of sodium hydrogen phosphate and sodium potassium tartrate), 0.40 mL salicylate-nitropuccide reagent, and 0.20 mL hypochlorite solution and mixed well. The resulting solution was allowed to stand for 30 min at room temperature for color development and was diluted to 10 mL using distilled water. The solution was vortexed prior to reading the absorbance at 660 nm. Total nitrogen content was calculated from the standard curve using the interpolation method, with ammonium sulfate as the standard. The protein content was calculated using Jones’ formula below:

(1)

Figure 1. Lagikway accessions tested for yield trial from June 2017 to February 2018: RXII 13-003 (a); RXII 13-019 (b); Lag 152649 (c).

A B C

Maghirang et al.: Yield, Proximate Composition, and Phytochemical Screening of A. manihot

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Phytochemical ScreeningSample preparation. Lagikway leaves were thoroughly washed in running water for 2–3 min and dried using cloth. Two (2) g of dried lagikway leaves were extracted with 20.0 mL 50% methanol (1:1 v/v absolute methanol: distilled water). The resulting mixture was vortexed for 3 min and centrifuged at 3000 rpm for 5 min. Aliquots of the supernatant were used to determine the total phenolic content, total flavonoid content, and antioxidant activity. Raw and blanched (3 min, boiling water at 100 °C) samples were screened.

Total phenolic content. The total phenolic content was quantified using the modified method of Velioglu et al. (1998). A 0.2-mL aliquot of the supernatant was diluted to 3.0 mL using distilled water and mixed thoroughly. One (1) mL of 0.2 M sodium carbonate and 0.2 mL of Folin-Ciocalteu reagent were added consecutively. The resulting solution was mixed thoroughly and placed in a hot water bath for 15 min. The solution was allowed to cool to room temperature and the absorbance was read at 710 nm using an ultraviolet-visible (UV-Vis) spectrophotometer. A standard curve was prepared using gallic acid as standard and the results were expressed as % total phenols.

Total flavonoid content. Total flavonoid content was determined using the method proposed by Ordonez and co-authors (2006). A 0.20-mL sample of the methanolic extract was diluted with 2.0 mL distilled water. The solution was then added with 0.30 mL of 5% sodium nitrite. After 5 min, 0.30 mL of 10% aluminum chloride was added and allowed to stand for 1 min at room temperature. And then, 1.0 mL of 1.0 M sodium hydroxide was added, and the solution was mixed using a vortex mixer. The absorbance of the colored solution was read at 510 nm using a UV-Vis spectrophotometer. A standard

curve was prepared using catechin as a standard, and the results were expressed as % total flavonoids.

Total tannin content. The determination of total tannin content used was a modified method from the study of Price and colleagues (1978). In detail, 20 mL of 50% methanol was used to extract 2.0 g of fresh sample. The mixture was vortexed for 10 min and centrifuged at 3000 rpm for 10 min. A 0.5-mL aliquot of the supernatant was added with 0.50 mL of 8 % HCl in methanol and 2.0 mL, 1 % vanillin solution. The resulting solution was mixed thoroughly and allowed to stand for 20 min. The absorbance was read at 500 nm. A standard curve was prepared using catechin as standard and the results were expressed as % total tannins.

DPPH (dinitrophenyl picryl hydrazyl radical) relative scavenging assay. The DPPH relative scavenging assay used is a modified method of Choi and colleagues (2002). A 1-mL aliquot of the plant extract was mixed with 4.0 mL distilled water, and 1 mL freshly prepared 1mM DPPH methanolic solution was added. The mixture was left to stand for 30 min before reading the absorbance at 517 nm using a UV-Vis spectrophotometer. A blank sample was also read at 517 nm. Total antioxidant activity was expressed using % RSA.

% Relative scavenging activity =

�1 − � Test sample absorbance � � * 100 (2)

Blank sample absorbance

Data AnalysisThe STAR statistical program was used for all analyses. Proximate composition was carried out in a completely randomized design with three replicates, while

Table 1. Weather conditions during the yield trial of lagikway from June 2017 to February 2021.

Month and year Parameter

Total rainfall (mm)

Mean relative humidity (%)

Mean wind speed (kph)

Mean temperature (°C)

June 2017 119.8 84 1.4 29.1

July 2017 284.6 87 2.2 28.0

August 2017 231.3 88 1.6 28.2

September 2017 457.1 87 1.8 28.2

October 2017 321.4 92 1.7 27.6

November 2017 315.7 90 3.1 27.7

December 2017 283.9 91 3.3 26.4

January 2018 77.3 92 3.4 26.1

February 2018 34.1 89 2.9 26.6

Data obtained from the University of the Philippines Los Baños–National Agromet Station



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phytochemical screening was carried out in a split-plot completely randomized design with three replicates as well. Data were subjected to analysis of variance, and differences among treatments were assessed by the least significant difference at p < 0.05.

RESULTS AND DISCUSSION

Morphological Traits and Yield of LagikwayLagikway is an underutilized vegetable unfamiliar to many consumers in the Philippines. It is a semi-perennial shrub that grows up to 2.5–3 m in height, as was also observed on the accessions evaluated (Preston 1998). The leaves are palmately lobed with varying depth. The accessions in this study have four lobes and cuts almost up to the base of the leaf. Another accession collected, which is not evaluated for yield, is barely lobed. Flowers are yellow and terminal. Flowering is rarely observed on the lagikway accessions collected from 2013 to early-2020. Only one accession, RXII 13-019, flowered twice – on February 2017 and February 2018. Seed set was observed in 2018, while none was observed in 2017. Flowering is also rarely observed in Papua New Guinea collection (i.e. 13 out of 112 accessions) (Preston 1998).

Although there were differences in terms of the morphological traits (i.e. leaf shape and lobing, flowering) of these three accessions, morphological diversity studies of this crop in the Philippines in a wide collection of germplasm are not yet explored. The greatest diversity of this crop is observed in Papua New Guinea, the Solomon Islands, and Vanuatu where one can observe 10 or more different cultivars in one garden (Preston 1998). Rich morphological diversity is also reported on accessions collected in West Papua, Indonesia (Prabawardani et al. 2016). The most evident diversity of morphological traits was observed in leaf shape and length, plant height, stem color and diameter, internode length, and petiole length and color.

Yield trial of this crop has been conducted in some parts of the world but not in the Philippines. It was observed in this study that shoot yield during 7.5 mo of data gathering ranges from 21.36 tons/ha (RXII 13-019) to 24.50 tons/ha (RXII 13-003) (Table 2). The number of shoots that can be harvested per plot ranges from 2201 (RXII 13-003) to 2675 (RXII 13-019). Other studies say that yield ranges from 4–15 t/ha (Westwood and Kesaan 1982; Kurika 1984/1988; Woruba and Ososo 1990) [cited by Preston (1998)]. Gurnah (1993) mentioned that 40–60 tons/ha/yr can be achieved when plants are well-watered and manured. Despite a lack of statistical significance in yield among entries, it can be said that lagikway can provide a continuous supply of leaves for a long time

starting at 1 MAT up to 7.5 MAT at 2-wk intervals and with a total of 14 harvests. On average, it can provide 800 g of young leaves and shoots every 2 wk of harvest. Observations in other studies say that 4–6 harvests can be done at 1–2-wk intervals before quality declines with leaf disease, senescence, and insect damage (Preston 1998). This crop remains productive for at least a year (Gurnah 1993), although some other authors say that it can remain productive for up to 2 yr (Prabawardani et al. 2016).

Shown in Figure 2 is the trend of lagikway shoot yield over time starting from 1 MAT. Harvested shoots were slowly increasing, although almost at a steady pace, from 1 to 3 MAT and eventually reached its peaks at 3.5 and 5 MAT. Thereafter, yield drastically lowered, increased a bit, and then decreased again from 6.5 to 7.5 MAT. Notice that the peak of the harvest was observed during the rainy months, as indicated in Table 1 (August–September), and the yield slowly decreased during the months (January and February) when rainfall is slowly decreasing and as the season approached the dry season.

This study showed that harvesting can be done at 2-wk intervals, but another author recommends that harvesting should be done at 4-wk intervals (Gurnah 1993). Although our study did not determine the effects of harvesting frequency on the yield of lagikway, frequent harvesting may reduce shoot density over time and eventually affect its productivity. A separate study on a forage crop, Cynodon nlemfuensis, had decreasing dry matter yield with increasing harvest frequency. The reduction in dry matter yield with repeated harvests is due to the leaf component of the sward outweighing the stem components (Timpong-Jones et al. 2015). The leaf yield of malunggay (Moringa oleifera) is higher with a longer harvest interval (8 wk) at 0.5 m x 0.5 m planting distance (Patricio et al. 2017).

Proximate Composition of LagikwayProximate analysis of lagikway revealed that the major component of this indigenous vegetable is water, comprising 85.18–86.42% of its total weight, followed

Table 2. Yield data of lagikway from Jul 2017 to February 2018.

Accession Shoot yield per plot (kg)

No. of shoots per plot (kg)

Potential yield (t/ha)

RXII13-003 12.25 2201.00 24.50

RXII13-019 10.68 2674.50 21.36

Lag 152649 10.97 2267.75 21.94

aC.V. (%) 18.81 49.72

aCoefficient of variation



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by nitrogen-free extract or total carbohydrates with 7.10–8.09 and 2.49–2.90% protein. Fat content ranged from 0.92–1.10%, while fiber content ranged from 1.17–1.30%. Moisture content is highest in RXII 13-019, while the fat content is highest in RXII 13-003. Lag 152649 is superior in protein content and total carbohydrates (NFE). On the other hand, ash and fiber are the same among lagikway accessions. The proximate composition of lagikway accessions is summarized in Table 3. All parameters measured are statistically different among accessions (p < 0.05) except ash and fiber contents. The variability in the nutritional quality of different lagikway accessions can be a basis for crop improvement in producing a lagikway variety with improved nutritional quality.

Proximate composition done in this study is based on the edible portion of lagikway, which includes the tender leaves and shoots. Gurnah (1993) mentioned that for every 100 g edible portion of aibika leaves and stem tips, it has 90 g water, 4.1 g protein, 0.4 g fat, 4 g carbohydrates, and 1 g fiber. In other works of literature, the proximate composition of five accessions of gedi leaves on a dry basis ranged from 11.15–14.27% ash, 18.76–24.16%

crude protein, 13.06–17.53% crude fiber, 1.06–4.51% crude fat, and 28.76–37.18% N-free extract (Mandey et al. 2014). Moreover, leaves of accessions from Kiribati and Tuvalu are reported to have 16–20% protein content (Lyons et al. 2010).

In comparison with commonly consumed leafy vegetables like cabbage, lettuce, and sweet potato, the proximate composition of lagikway is comparable to that of sweet potato, except for fiber content and NFE where sweet potato is superior. Lagikway is superior to cabbage and lettuce in all proximate components, except for the fiber content of cabbage. Table 4 summarized the data for the comparison of these leafy vegetables (USDA 2016).

High water content leafy vegetables are easily degraded because of increased microbial activity (Punchay et al. 2020). In addition, its high moisture makes it more susceptible to attacks of insects and pests (Hammond 2015). This suggests that preservation processes like drying are imperative and very important to prolong the shelf-life of vegetables like lagikway.

Figure 2. Trend of lagikway shoot yield and no. of shoots over time (7.5 MAT) starting from harvesting on July 2017–February 2018.



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Phytochemical ScreeningPhenolic compounds, the biggest group of phytochemicals present in plants, function primarily as plant secondary metabolites. This group – which includes phenolic acids, flavonoids, and tannins – is important because of its associated bioactivities. Several studies suggest that phenolic compounds are responsible for the plants’ defense against pathogens and predators. These compounds are also accounted for the high antioxidant activity of plants because of their high redox potential, which makes this group a good reducing agent, hydrogen donor, and oxygen free radical quenchers and ultimately plays an important role in preventing degenerative diseases. (Ignat et al. 2011).

Phytochemical screening was done in Lagikway accessions. Flavonoids, phenols, tannins, and antioxidant activity (% RSA) were quantified for each accession. Fresh lagikway methanolic leaf extracts yielded 2.27–2.65% phenolic content, 10.96–15.44% flavonoid content, 5.43–9.37% tannin content, and 23.86–28.43% RSA. Lag 152649 was observed to be superior in all of the parameters measured registering 2.65% phenolics, 15.44% flavonoids, 9.37% tannins, and 28.43% RSA. The results of the phytochemical screening for Lagikway are summarized in Table 5.

All parameters measured are statistically significant among accessions (p < 0.05). A strong positive correlation was seen in all parameters measured against the antioxidant activity, which is in agreement with the study of Wen and co-workers (2010) among water extracts of different vegetables.

Indonesian red gedi leaf ethanolic extract was found to have higher total phenolic (3.37%) and total flavonoid (22.24%) contents compared to the local germplasm of lagikway studied. In contrast, the tannin content of the local lagikway accessions is higher compared to the Indonesian red gedi leaves, which contain 1.34% tannins (Tandi et al. 2016).

Table 3. Proximate composition of lagikway accessions.

Entry % moisture % fat % protein % ash % fiber % NFE

RXII 13-003 85.79ab 1.10a 2.49b 1.64 1.30 7.67ab

RXII 13-019 86.42a 0.92b 2.84a 1.56 1.17 7.10b

Lag 152649 85.18b 0.97ab 2.90a 1.66 1.19 8.09a

CV (%) 0.53 6.47 2.66 5.62 9.90 4.74

Column means with similar subscripts are not significantly different at p < 0.05.

Table 4. Comparison of proximate composition of lagikway with common leafy vegetables.

Samples % moisture % fat % protein % ash % fber % NFE

Lagikway 85.8 1 2.74 1.62 1.22 7.62aCabbage 92.52 0.18 1.21 0.72 2.3 5.37aLettuce 95.63 0.22 1.35 0.57 1.1 2.23aSweet Potato 86.81 0.51 2.49 1.36 5.3 8.82

aProximate values were derived from the US Department of Agriculture–Agricultural Research Service (2016)

Table 5. Phytochemical screening of fresh and blanched Lagikway accessions.

Functional properties Entry Fresh Blanched

% RSA RXII 13-003 23.86c 11.80b

RXII 13-019 25.49b 13.21a

Lag 152649 28.43a 11.09b

% Phenols RXII 13-003 2.27b 1.31c

RXII 13-019 2.30b 1.41b

Lag 152649 2.65a 1.88a

% Flavonoids RXII 13-003 10.96c 3.66c

RXII 13-019 12.40b 7.23a

Lag 152649 15.44a 5.93b

% Tannins RXII 13-003 5.43b 0.49

RXII 13-019 6.74b 0.53

Lag 152649 9.37a 0.47

Column means with similar subscripts between groups (i.e. functional property) is not significantly different at p < 0.05; RSA – relative scavenging activity (antioxidant activity, DPPH).



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Effect of Blanching in the Phytochemicals of Lagikway Lagikway young leaves and shoots in the Philippines is not eaten raw based on a survey conducted. It is usually blanched in water, aside from being mixed with other vegetables, either sautéed or with coconut milk (Maghirang et al. 2018). Blanching is a thermal treatment, which inactivates the enzymes and destroys microorganisms that contaminate raw fruits and vegetables during the post-production process. It involves heating the plant part to a specified temperature and time, after which it is rapidly cooled or passed immediately to the next process (Xiao et al. 2017). Recommended blanching time for some leafy vegetables like Cnidoscolus asconitifolius, Talinum triangulare, Celosia argentea, Amaranthus hybridus, Vernomia anygdalina, and Telfaria occidentalis ranged from 1–5 min (Bamidele et al. 2017).

Statistical analysis showed that blanching greatly affected all the functional properties tested in this study (Table 5). A significant interaction of treatment (i.e. blanched and fresh) and entry (i.e. accession) was observed, which signifies that all of these phytochemicals were affected by blanching. For the phenolic content, blanching was reduced to 36% on average. Phenols present in Lag 152649 are highest among the entries, whether for fresh or blanched samples.

Blanching also lowered the flavonoid content by 57% on average. Lag 152649 had the highest flavonoids in fresh samples, but it is noteworthy that RXII 13-019 had the highest flavonoids at 7.23% in blanched samples. This means that flavonoids after blanching is less affected in RXII 13-019 compared to the other samples. In fact, % loss in blanching is 41.73% in RXII 13-019, while the loss in the other two accessions is more than 60%. RXII 13-003 remained the lowest for fresh and blanched samples.

In general, blanching has a negative effect on vitamins and phenolic compounds, which tend to be unstable when subjected to heat treatment (Prochaska et al. 2000). In a separate study, flavonoids and phenol contents of york

cabbage were also reported to decrease by as much as 50% after blanching for 2 min at high blanching temperatures (Jaiswal et al. 2012). The reduction in the concentration of these compounds due to blanching can be attributed to the oxidation of phenolic compounds and hydrolysis of plant cell wall components with bound phenolics that ultimately result in their leaching in blanching water (Irondi et al. 2016).

Tannins of lagikway registered the highest decrease in concentration among the phenolic compounds studied with a 93% reduction upon blanching. Blanching increases the activity of the enzyme polyphenol oxidase, which degrades tannins and other polyphenol compounds (Kunyanga et al. 2011). This trend is also seen in the study of Sze-Tao and colleagues (2001), where 98% of assayable tannins is lost in walnuts after blanching for 2 min. In addition, blanching resulted in insignificant tannin content variation among lagikway samples.

Phenols, tannins, and flavonoids are the phytochemicals usually responsible for the bitter and unpleasant taste of green leafy vegetables (Drewnowski and Gomez-Carneros 2000). In general, blanching decreases the phytochemical content of leafy vegetables like lagikway, but it removes the unpleasant taste of the vegetables, causes enzyme inactivation, and prolongs their shelf life (Fellows 2000).

Blanching also lowered the antioxidant activity by more than half (53%). The same results were observed in blanching Ocimum gratissimum, with a 51.5% reduction in antioxidant activity (Oboh 2005). The decrease in antioxidant activity during blanching is reported in numerous studies, and it can be attributed to the leaching of soluble antioxidants into boiling water (Xu and Chang 2008; Wen et al. 2010). On the contrary, other studies have seen an increase in antioxidant activity after blanching (Viña et al. 2007). RXII 13-019 is the accession that is least affected by blanching, as it had the highest antioxidant activity value (13.21% RSA) after blanching. Table 6 summarizes the results of blanching in phytochemicals and antioxidant capacity of lagikway.

Table 6. Effect of blanching on different phytochemicals and antioxidant capacity of Lagikway.

Sample% lost/gained due to blanching

Phenolics Flavonoids Tannins RSA

RXII 13-003 –42.2907489 –67.00274977 –91.54929577 –50.9205

RXII 13-019 3.47826087 –41.7752443 –91.97530864 –48.32162

Lag 152649 –29.0566038 –61.69934641 –95.02702703 –61.2039

Average –22.6230306 –56.82578016 –92.85054381 –53.48201



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CONCLUSIONYield trial in lagikway revealed that it can provide a continuous supply of leafy vegetables for the household. Also, the nutritional quality evaluation revealed that it contains significant levels of nutrients that are essential for human health. However, blanching the young leaves and shoots for 3 min at 100 °C lowered the functional properties of this vegetable. Although it appeared that there are no significant differences in yield, variety recommendation can still be done based on the differences in the nutritional quality of the three different accessions of lagikway. Based on the functional properties and antioxidant activity, Lag 152649 seemed to be superior compared to the other two accessions and, hence, can be recommended for multiplication, distribution, and promotion of this vegetable. Nevertheless, further evaluation on the palatability, nutritional quality (i.e. vitamins and minerals), and effects of other preparations on the nutrient composition of lagikway should be done for a more thorough recommendation.

ACKNOWLEDGMENTSThe authors wish to acknowledge the Department of Agriculture–Bureau of Agricultural Research for the research funds, as well as Ms. Elenita Castillo and Ms. Teresita Maligalig of the Analytical Services Laboratory and the staff of the Vegetables Section of the Institute of Plant Breeding at the University of the Philippines Los Baños for the technical assistance.

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