Passiflora quadrangularis L. belongs to the family Passifloraceae which bears larger fruit with edible juicy mesocarp and pulp known as a good source of phytochemicals. Cultivation and plant management practices are known to influence the phytochemical compositions of agricultural produce. This study aimed to examine the influence of the cultivation practices on the antioxidant activities and secondary metabolites of the organically and conventionally grown P. quadrangularis. Findings revealed organically treated P. quadrangularis plants showed enhancement in their antioxidant properties and secondary metabolites profiles. Among the plant parts, leaves of P. quadrangularis grown organically possessed higher antioxidant activities compared to the conventional in all assays evaluated. The antioxidant activities in the edible parts of the P. quadrangularis fruit have also been enhanced through organic cultivation with significantly higher total phenolic content and DPPH in mesocarp, and the pulp showed higher total flavonoid content, DPPH and FRAP. This observation is supported by a higher level of vitamins and secondary metabolites in the samples. The secondary metabolites profile showed mesocarps were phenolic rich, the pulps were flavonoids rich while leaves showed good composition of phenolics, flavonoids and terpenoids with outstanding antioxidant activities. The common secondary metabolites for organically produced P. quadrangularis in different plant parts include 2-isopropyl-3-methoxycinnamic acid (mesocarp and pulp), myricetin isomers (pulp and leaves), and malvidin-3-O-arabinoside isomers (pulp and leaves). This study confirmed that organic cultivated P. quadrangularis possessed higher antioxidant activities contributed by its vitamins and secondary metabolites.

Enzymatic browning is a common limiting factor in the fruit industry because it causes significant losses through fresh product deterioration, affecting taste, flavor, and nutrition. Artocarpus odoratissimus, locally known as terap, is an exotic indigenous fruit to Borneo. This fruit remains underutilized due to its perishability, short shelf-life, and peel browning. Currently, no information has apparently been published on the browning mechanisms of A. odoratissimus. Thus, the present study aims to evaluate the degree of browning and enzymatic activities in relation to the phytochemical contents in A. odoratissimus during postharvest ripening. The experimental design consists of packaging (without packaging and with packaging) and storage temperatures (ambient at 25 °C, and cold storage at 10 °C), which were arranged in a randomized complete block design. Findings showed significantly higher weight loss in fruit stored at 25 °C on days 4 (T1) at 12.20 ± 0.19% and 8 (T5) at 11.09 ± 0.24%. The degree of browning was higher in the fruits stored with packaging at 25 °C, collected on day 4 at 0.48 ± 0.01 and day 8 at 0.51 ± 0.02, and consequently, the phenylalanine ammonia-lyase (671.00 ± 5.25 UE g⁻¹ min⁻¹) and polyphenol oxidase (670.00 ± 2.56 UE g⁻¹ min⁻¹) enzymatic activities were also higher. The lower enzymatic activities were recorded in the fruit stored at 10 °C without packaging, resulting in the least degree of browning. The fruit with the lowest enzymatic activities was stored at 10 °C without packaging, resulting in the least amount of browning. This trend is supported by lower total phenolic content (TPC) and is explained by a strong positive correlation between TPC and PAL (r = 0.927). Low-temperature storage was effective in reducing the effect of browning and deterioration on A. odoratissimus for up to 16 days. The results not only provided insights into the peel browning in A. odoratissimus but also guidance on controlling postharvest fruit browning.

Background and Objective: The passion fruit industry uses half of the fruit mass for juice extraction, while the rest represents an agricultural by-product that consists of rinds and seeds. Generally, the seeds are disposed of after being crushed, causing a substantial burden on the environment. Thus, efforts have been made to utilize the seeds for useful resources. This study focused on the physicochemical characteristics, fatty acid and antioxidant properties of seed oil extracted from three Passiflora species [P. edulis Sims (Purple), P. quadrangularis and P. maliformis]. Materials and Methods: Passiflora seed oil was extracted using petroleum ether as a solvent and analysed for its physicochemical properties: refractive index, specific gravity, iodine value, saponification value, non-saponification matter, acid value, peroxide value and free fatty acid content. The fatty acid composition and antioxidant properties were also analysed. Results: Passiflora seeds were rich in oil content, yielding 24-30%. The Passiflora seed oil also possessed high values of iodine (124.67±0.67-131.00±0.58 g I2 100 g–1) and peroxide (1.43±0.12-3.23±0.12 meq kg–1) similar to other edible seed oils, e.g., sunflower. The seed oil contained essential fatty acids with a higher proportion of unsaturated fatty acids (>80%), mostly comprising linoleic and oleic acid. Passiflora edulis (Purple) seed oil had a comparatively higher total phenolic content (570.74±0.78 mg kg–1) and stronger antioxidant activity (33.63±1.46 mg mL–1). Based on principle component analysis (PCA), the biplot generated showed that Passiflora seed oils possessed characteristics similar to those of sunflower and soybean oils. Conclusion: The present findings revealed that the oil of Passiflora seeds, an agro by-product, is valuable and can be extracted for nutraceutical and pharmaceutical uses.

Artocarpus odoratissimus, locally known as terap, is native to Borneo and holds great potential for providing nutrition and income to rural communities. The fruit's flesh is consumed raw, while the seeds are typically steamed and used in local dishes. The by-products, such as the pedicel and peel, often go to waste. This indigenous species has yet to be fully explored for its nutritional and phytochemical properties. Hence, the present study aims to evaluate the nutritional compositions and phytochemical properties of A. odoratissimus fruit. The nutritional and phytochemical properties of A. odoratissimus vary across its parts. The edible flesh and seeds exhibited higher carbohydrate content at 12.16±1.01% and 9.96±0.76%, respectively. Seeds possessed significantly higher crude protein (21.89±0.54%) and fat (18.23±0.20%). In contrast, the non-edible parts of the peel (5.57±0.11%) and pedicel (5.79±0.41%) exhibit considerably greater ash content than their edible counterparts in the flesh (3.87±0.42%) and seeds (0.62±0.29%). Potassium (905.61±18.89 to 2001.51±13.00 mg 100 g^-1) was the most abundant in A. odoratissimus fruits, followed by calcium (578.30±7.00 to 1300.97±23.51 mg 100 g^-1). The flesh is primarily composed of non-reducing sugars, including fructose (26.70±0.70 g 100 g^-1) and glucose (25.38±0.45 g 100 g^-1), with a notable amount of vitamin B1 (11.07±0.31 mg 100 g^-1). The seed oil contains essential fatty acids, with a significant proportion of unsaturated fatty acids (57.10%), mainly nervonic acid (45.32%). The pedicel, often considered a by-product, exhibits relatively high levels of phytochemical properties in comparison to the edible portions. The current findings support the ethnobotanical uses of A. odoratissimus by local communities, underscoring its growing importance in the nutraceutical and pharmaceutical industries.

Caulerpa lentillifera (phylum: Chlorophyta) is a seaweed that is widely consumed by local communities across Asia. The effects of different oven-dried temperatures on the drying kinetics and phytochemical constituents of C. lentillifera were studied. This kinetic study used three different thin-layer models, i.e., Lewis, Henderson and Pabis, and Logarithmic models. Among these, the Logarithmic model was the most suitable model that could be determined the seaweed drying behaviours (R-square > 0.9923, RMSE < 0.0004). Drying the C. lentillifera at 50oC resulted in a higher extraction yield (1.00%) with a significant concentration of total phenolic content and total flavonoid content at 1.027 mg GAE/g, and 59.655 mg RU/g, respectively.

Volatile organic compounds determine the aroma properties of durian, and it is an important factor in durian acceptance by consumers. However, limited information is devoted to volatile organic compounds and aroma in wild edible durians. Therefore, the present study aims to characterize and compare the volatile organic compounds and aroma properties of the indigenous wild edible durians from Sarawak, Borneo. Seven genotypes, namely Durio dulcis, Durio graveolens (yellow-fleshed), Durio graveolens (orange-fleshed), Durio graveolens (red-fleshed), Durio kutejensis, Durio oxleyanus, and Durio zibethinus were characterized in this study. Solid phase microextraction combined with gas chromatography-mass spectrometry (SPME GC-MS) was used to detect the volatile organic compounds, while the quantitative descriptive analysis (QDA) method was used to characterize the aroma properties of wild edible durians. A total of 119 volatile organic compounds comprising alcohol, aldehyde, amine, ether, ester, ketone, nitrogen-containing, and sulfur-containing compounds were detected. Ester and alcohol compounds are the most predominant in the composition, especially D. graveolens (yellow- and orange-fleshed), and D. dulcis possessed three to nine times higher relative amount of ester compounds. PCA clearly classified the wild durians into different groups. Based on the QDA analysis, D. kutejensis has the mildest aroma among wild edible durians, while D. dulcis perceived a stronger sweet and grassy aroma. Partially Least Square (PLS) regression model analysis indicated a strong relationship between the volatile organic compounds and the aroma intensity perceived by the panelists. These findings could be the major component in the durian industry, paving the way for breeding efforts to create new cultivars that can improve consumers’ satisfaction.