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This study aims to isolate and characterise the Pink Pigmented Facultative Methylotrophs (PPFM) bacteria from the leaves of common Malaysian table salad (ulam). The colonies of PPFM bacteria were obtained using selectively modified Pseudomonas agar based on the appearance of the pink pigment colony. The three selected isolates labelled OJ4, OJ154 [Oenanthe javanica (Blume) DC.] and ML8 [from Melicope lunu-ankenda (Gaertn.) T. G. Hartley] were chosen for characterisation. The result showed the PPFM bacteria colonies (log CFU/g) at the leaf surface of C. caudatus are 4.4 ± 0.1, significantly higher than O. javanica, 3.8 ± 0.2, and M. lunu-ankenda, 3.2 ± 0.1. The selected isolates belong to the Gram-negative group, motile with rod shape with size [length (l) × width (w)] in µm unit 4.3 ± 1.1 × 1.6 ± 0.6, 5.4 ± 0.2 × 1.2 ± 0.1, and 3.5 ± 0.7 × 1.0 ± 0.0, respectively. They show positive urease, catalase, and oxidase activities, while none of them can degrade starch, gelatine, or cellulose, as well as glucose fermentation (MR test) and metabolism actions (VP test), producing indole and hydrogen sulphide gaseous. Only isolate OJ154 demonstrates positive casein hydrolysis and nitrate reduction activities, while only isolate ML8 can utilise citrate but not in lipid degradation. Their sequence analysis of the 16S rRNA indicated that OJ4 and ML8 are Methylobacterium radiotolerans with a similarity of 99%, whereas, OJ154 is Methylorubrum salsuginis with a similarity of 99%. To conclude, PPFM bacteria from the leaves of C. caudatus, O. javanica, and M. lunu-ankenda have been isolated and characterised in particular. [ABSTRACT FROM AUTHOR]

Various microorganisms can grow in egg-based food products, and yeast is among the microorganisms that thrive in egg products. Yeasts naturally produce large enzymes by breaking down organic materials during growth. Yeast has a great biotechnological potential owing to its extracellular enzymatic activity. Therefore, it is important to study yeast species, especially those from food sources and the environment. Protease production and activity are affected by various factors such as temperature, time, and pH. In this study, 47 yeast isolates were identified and purified from traditionally processed Indonesian duck eggs via repeated sub-culturing and quadrant streaking. Screening of the yeast isolates on skim milk agar medium showed that 23 isolates exerted proteolytic activity, whereas the remaining 25 did not. Yeast isolates with proteolytic capabilities belonged to the Saccharomyces, Pichia, and Candida genera. The highest protease activities were observed in isolates TA-17 and TPi-08, with activity values of 0.618 and 0.098 U/mL, respectively. [ABSTRACT FROM AUTHOR]

Euphorbia tirucalli, commonly known as the pencil cactus or milk bush plant, is used as an alternative medicine. The current study evaluated the phytochemical contents, antibacterial, anticandidal, and antisporicidal potential of the E. tirucalli methanolic extract. The antibacterial and anticandidal activity of E. tirucalli methanolic extract was determined by performing a disc diffusion assay, MIC, MBC, and MCC. The sporicidal activity was tested at different concentrations of extract and exposure times. Phytochemical analyses revealed the presence of alkaloids, saponins, cardiac glycosides, terpenoids, and tannins in E. tirucalli methanolic extract. Results demonstrated inhibition zones of the extract against Gram-positive bacteria were in range of 22.00-7.00 mm. Meanwhile, inhibition zones of the extract against Gram-negative bacteria were in range of 13.00-7.00 mm. All bacteria were inhibited with MIC values at 1.56-25.0 mg/ml and can be completely killed with MBC values of 20-200 mg/ml. Inhibition zones of E. tirucalli methanolic extract against Candida spp. were in the range of 20.00-8.00 mm. All Candida spp. were inhibited with MIC values at 1.56-100.00 mg/ml and MBC values of 100-300 mg/ml. All concentrations of the extract inhibited all Bacillus spp. spores at different exposure times. In conclusion, the methanolic extract of E. tirucalli exhibits antibacterial, anticandidal, and sporicidal activities. The findings indicated that the methanolic extract of E. tirucalli has good potential for prospective nature-based antimicrobial agents. [ABSTRACT FROM AUTHOR]

Spontaneous fermentation is becoming ever more elusive because of vast natural microbiota profiles that affect geographical region, climate, and applications of agrichemicals. This study aimed to identify the physicochemical and sensory properties of local planted (Serdang, Malaysia) Robusta (Coffea canephora L.) coffee beans after undergoing different spontaneous wet fermentation (SWF) periods i.e., 0 days as control, 3 days, and 5 days. The hardness decreased significantly (p < 0.05) by 80 to 90% in roasted fermented roasted Robusta coffee (FRRC) beans. The carbohydrate content was significantly higher (p < 0.05) at 9.4%, but protein and crude fibers were significantly (p < 0.05) lower at 31% and 9.7%, respectively. While the FRRC brew displayed deeper lightness (L*31.983), the FRRC powder displayed lighter lightness (L*49.553). The total soluble solid (TSS) was around 21% higher in FRRC and the water solubility index (WSI) had equivalent outcomes at about 8% higher in FRRC. Rheological analysis showed that the coffee fluid exhibited a shear-thickening property with fluid elastic components greater than viscosity. FRRC beans received higher ratings (score > 6) than non-FRRC beans (score between 5 and 6) in the consumer sensory evaluations. [ABSTRACT FROM AUTHOR]

Robusta coffee is one of Malaysia’s most planted species due to its ability to adapt to the local climate. Nonetheless, the coffee species was perceived as having lower quality and economic value due to bitterness and astringency. It is widely believed that higher caffeine and chlorogenic acid contents in Robusta coffee beans contributed to the unfavourable bitter and astringent flavour. Hence, the present study intends to evaluate the effect of spontaneous wet fermentation (SWF) of locally grown Robusta (Coffea canephora L.) coffee towards the microbiological properties, phytochemical constituents, in particular caffeine and chlorogenic acids (CGA), total phenolic content (TPC), and antioxidant properties. The SWF of green Robusta coffee beans from University Agricultural Park (UAP), Universiti Putra Malaysia, Serdang, Selangor, took place at ambient temperatures between 25 to 28°C, and the pH decreased from 5.2 to 3.64 over five days of fermentation. The total plate count, lactic acid bacteria (LAB) and yeasts were significantly increased to approximately 7 Log10 CFU/g. The SWF has reduced caffeine content by 35%, while the CGA has decreased by roughly 20%. The SWF also led to an increase in TPC of approximately 31.5% and an increase in antioxidant activity of approximately 60%. [ABSTRACT FROM AUTHOR]

Aims: Jambu batu (Psidium guajava Linn.) is a phytotherapic plant used in folk medicine that has active components to treat various diseases. An earlier study has reported on the analysis of its pharmacological properties and was found to possess antibacterial, antifungal, anti-inflammatory and antioxidant activity. The present study aimed to determine the antibacterial activities of P. guajava Linn. leaves extracts on the vegetative cells of Bacillus cereus ATCC33019, Bacillus megaterium ATCC14581, Bacillus pumilus ATCC14884 and Bacillus subtilis ATCC6633 and to evaluate its effects of different temperatures and pHs on antibacterial activity. Methodology and results: The susceptibility test used to determine the bacterial growth inhibition were well diffusion assay (WDA), minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill curve assay. The effects of various parameters on temperatures at 10 °C, 28 °C, 30 °C, 50 °C and 80 °C and pH at 3.0, 5.0, 6.7, 7.0 and 11.0 were investigated. WDA assay of the extracts resulted in 13.75 ± 0.95 and 16.25 ± 0.95 mm of inhibition zone on B. subtilis and B. cereus, respectively. The extracts can inhibit the growth with MICs value range of 0.195 to 0.781 mg/mL for B. megaterium and B. pumilus, respectively, and can kill all tested Bacillus spp. with MBCs values of 0.781 mg/mL. The killing time analyses showed that Bacillus spp. can be killed completely within 4 h at 4× MIC (0.781 to 3.124 mg/mL). The extracts remained stable under a wide range of temperatures and pHs, as there was no significant difference in the MIC and MBC values. Conclusion, significance and impact of study: Psidium guajava Linn. ethanolic leaves extract yielded good antibacterial activities, suggesting that the extract can be utilised or explored as a potential anti-Bacillus agent in food applications. [ABSTRACT FROM AUTHOR]

Edible bird’s nest (EBN) hydrolysate is widely used in EBN downstream products. This study aimed to optimize the process conditions (combination of heat treatment and enzymatic hydrolysis) to produce high-yield and high-quality EBN hydrolysate. The effects of four factors in the process were studied by response surface methodology. The experimental factors are EBN temperature during double boiling (DB), DB duration, enzymatic hydrolysis duration, and the ratio of EBN to water. The recovery (yield) and quality (sialic acid [SA], 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid [ABTS], and 2,2-diphenyl-1- picrylhydrazyl [DPPH]) of the final product were used as response variables. The Pearson correlation coefficient showed that: EBN temperature during DB affected product recovery (p < 0.01) and ABTS (p < 0.01), DB Duration affected DPPH (p < 0.01), and the ratio of EBN to water affected product recovery (p < 0.01). The duration of enzymatic hydrolysis was not significantly correlated with any of the responses and least significant factors in the model. Two optimal conditions for the processes obtained from this study were yield (product recovery) and quality. This study also showed that EBN hydrolysate produced from EBN by-products could be used as a nutraceutical because of the antioxidant activity and high SA content. [ABSTRACT FROM AUTHOR]