Penentuan aktiviti antioksidan dan antikanser di dalam teh Sabah serta potensinya sebagai makanan tambahan

Peningkatan minat di kalangan pengguna dan kajian saintifik mengenal kebaikan teh terhadap kesihatan telah membuka Iembaran temadap kajian ekstrak teh sebagai salah satu cabang makanan tambahan. Oleh ltu, bagi kajian ini, Teh Sabah dinilai untuk menentukan komposisi fungsian yang terdapat di dalam daun Teh Sabah untuk menentukan kebaikannya sebagai makanan tambahan. Oleh kerana itu, komposisi nutrien dan kimia, aktiviti antioksidan, sifat antikanser dan kesan toksikologi ditentukan dengan menggunakan pelbagai jenis analisis berdasarkan jenis rawatan dan tahap kematangan daun teh. Kandungan flavanol (EGc, catechin hydrate, EC, EGCG dan ECG) dalam daun Teh Sabah dikaji pada daun teh segar dan fennentasi pada tiga tahap kematangan laitu daun muda, matang dan tua dengan menggunakan analisis HPLC. Didapati jenis rawatan (segar dan fennentasi) dan tahap kematangan daun mempunyai kesan yang signifikan terhadap kandungan flavanol. Daun segar mengandungi lebih flavanol berbanding yang difennentasi dan daun muda mengandungl yang terbanyak diikuti daun matang, dan tua. Ravanoi yang tertinggal kandungannya adalah EGC diikuti ECG, catechin hydrate, EGCG dan akhlmya EC dalam semua kematangan dan jenis rawatan. Bagl aktiviti antikanser, teh hijau mempunyai kesan sitotoksik yang lebih tinggl dan kaedah pengekstakan metanol adalah lebih baik berbanding air panas. Selaln itu, terdapat kesan sitotoksik di dalam teh buangan dan kaedah pengekstrakan air panas dapat memberikan kesan sitotoksik yang lebih tinggl bagi jenis teh tersebut Bagi aktiviti antioksidan, teh hitam dan kompos teh hitam d1analisis untuk jumlah polifenol, jumlah flavonoids dan kapasiti aktiviti antioksidant. Sampel diekstrak dengan menggunakan pelarut akues metanol dan air panas. Kapasltl aktiviti antioksidan ekstrak ditentukan dengan menggunakan kaedah perencatan radikal DPPH dan ABTS serta kaedah FRAP. Keputusan menunjukkan efisiensi peratus pengekstrakan adalah lebih tinggl dalam pelarut akues metanol berbanding dengan pelarut air panas. Kandungan polifenoi dan flavonoid adalah lebih tinggl dalam teh hitam daripada kompost teh hitam manakala kaedah perencatan radikal ASTS dan DPPH, ekstrak teh air panas mempunyai peratus perencatan radikal yang tinggl berbanding dengan ekstrak teh akues metanol. Semua kaedah yang digunakan mendapati teh hitam mempunyai kapasiti antioksidan yang tinggl berbanding dengan kompos teh hitam. Kajlan toksisiti subkronik ekstrak teh Sabah selama 28 hart telah dijalankan terhadap tikus Sprague Dawley jantan dan betina (umur;13 dan 8 minggu). Tikus jantan dan betina masing-masing terdiri daripada empat kumpulan yang diberikan kepekatan dos yang berbeza laitu 0 (kawalan), 1250, 2500, dan 5000 mg/kg b.b.hari. Sebanyak 2.7 dan 1.4 ml ekstrak teh Sabah masing-masing telah diberikan kepada tikus jantan dan betina secara suapan paksa. tiada sebarang kematian dan petanda perubahan klinikal yang jelas dapat diperhatikan pada tikus sepanjang tempoh kajian kecuali pengurangan berat badan tikus jantan yang diberikan dos 5000 mg/kg b.b/hari. Peningkatan enzim alanin transferase dan kreatinin pacta tikus betina tidak dikira sebagai kesan tokslkologl kerana tiada sebarang perubahan pada berat hati dan buah pinggang relatif diperhatikan. Berdasarkan pemerhatian, kepekatan dos paling rendah yang menampakkan kesan sampingan (lowest observed adverse effect level, LOAEL) terhadap tikus jantan adalah 5000 rngJkg b.b/hari. Bagi tikus betina pula, kepekatan dos 5000 mg/kg b.b.hari adalah pada paras yang tidak menampakkan sebarang kesan sampingan terhadapnya (no observed adverse effect level, NOAEL)

Proximate and fatty acid composition of Sabah Yellow Durian (Durio graveolens)

Kajian ini dijalankan untuk menentukan komposisi proksimat dan juga kandungan asid lemak durian kuning (Durio graveolens Becc.) Sabah. Kandungan lembapan, abu, protein kasar, lemak kasar, serat kasar, karbohidrat dan asid lemak telah ditentukan. Keputusan analisis proksimat menunjukkan durian kuning Sabah mempunyai kandungan lembapan sebanyak 66.5%, protein 3.1%, lemak 5.5%, abu 1.1%, serat kasar 3.7% dan 20.2% karbohidrat. Sebanyak 13 komponen asid lemak telah dikenal pasti dengan peratusan asid lemak tepu adalah lebih rendah (30.3%) berbanding asid lemak tidak tepu (69.7%). Peratusan asid lemak tepu yang paling tinggi adalah asid miristik (14.5%) manakala asid laurik adalah terendah (1.3%). Untuk asid lemak tidak tepu pula, asid oleik paling tinggi (22.2%) manakala asid lemak miristoleik paling rendah (1.9%

Phytochemicals and antioxidant properties of different parts of Camellia sinensis leaves from Sabah Tea Plantation in Sabah, Malaysia

This study was conducted to determine the total phenolic (TPC) and total flavonoid content (TFC) as well as the antioxidant activity of 50% ethanolic extracts from different parts of Camellia sinensis (shoot, young and matured leaves). Comparison was also made between black (fermented) and green (unfermented) tea. For green tea, the results showed that the shoot contained significantly higher total phenolic content, followed by the young and matured leaves (p<0.05). The same trend was also observed for antioxidant activity as assessed using FRAP (ferric reducing/antioxidant power), DPPH (2,2-diphenyl 1-picrylhydrazyl) free radical scavenging assay and ABTS (2,2’-azinobis(3-ethylbenzthiazoline)-6-sulphonic) radical scavenging assays. As for black tea, the highest total phenolic and total flavonoid content were observed in the shoot, followed by the young and old leaves. The same trend of antioxidant activity with green tea was also observed in black tea extracts. In addition, black tea compost showed comparable high total phenolic and flavonoid content as well as antioxidant activities as assessed using different antioxidant assays. High antioxidant activity of tea leaves grown in Sabah might be contributed by phenolic phytochemicals that presence in the extract

The effects of extrusion conditions on the properties of Amplang, a traditional fish snack in Borneo

The effects of extrusion process parameters on Amplang fish snack production are investigated in this study using a single-screw extrusion machine. The extrusion parameters are based on two factors, namely the barrel temperature (100 - 140oC) and screw speed (146 - 208 rpm). The central composite design (CCD) is used to produce thirteen experimental combinations and the effects of the extrusion parameters on the physical and functional characteristics (hardness, bulk density, expansion ratio, and water absorption and solubility indexes) of the Amplang fish extrudate were assessed as responses. The fish extrudates investigated in this study varied between 45.57 - 246.33 N (hardness), 0.09 - 0.21 g/cm3 (bulk density), 1.00 - 2.67 (expansion ratio), 2.58 - 4.01 g/g (water absorption index), and 19.25 - 29.8% (water solubility index). The bulk density, expansion ratio, water absorption index, and water solubility index were shown to be significantly (P < 0.05) affected by the barrel temperature and screw speed. In conclusion, barrel temperature and screw speed can influence the physical and functional properties of extruded fish snacks and the extrusion technique demonstrated in this study can be utilised to produce Amplang fish snacks in Sabah

Current status of food safety hazards and health risks connected with aquatic food products from Southeast Asian region

Food safety issues associated with aquatic food products become more important with the increasing consumption and followed by its ongoing challenges. The objective of this paper is to review the food safety hazards and health risks related to aquatic food products for the Southeast Asian region. These hazards can be categorized as microplastics (MPs) hazard, biological hazards (pathogenic bacteria, biogenic amines, viruses, parasites), and chemical hazards (antimicrobial, formaldehyde, heavy metal). In different Southeast Asian countries, the potential health risks of aquatic food products brought by food hazards to consumers were at different intensity and classes. Among all these hazards, pathogenic bacteria, antimicrobials, and heavy metal were a particular concern in the Southeast Asian region. With environmental changes, evolving consumption patterns, and the globalization of trade, new food safety challenges are created, which put forward higher requirements on food technologies, food safety regulations, and international cooperation

Extraction process and applications of mushroom-derived protein hydrolysate: A comprehensive review

Significant attention is focused on mushrooms and mushroom protein hydrolysates owing to their sustainability and nutritional profile with different uses in diverse industries. This review examines the composition, functional properties, production methods and applications of mushroom protein hydrolysates. It commenced with a brief overview of protein hydrolysates where their importance and applications in food, pharmaceutical, cosmetic, and agricultural industries were explored. The significance of mushrooms as alternatives to animal proteins applicable to producing protein hydrolysates was discussed. Methods including conventional (chemical and enzymatic) extraction, ultrasound-assisted and microwave-assisted extractions used to extract proteins during protein hydrolysates production were discussed. Using enzyme-assisted-ultrasound-extraction to enhance protein extraction efficiency is exclusively highlighted as a promising technique. To obtain enhanced protein yield and quality, and protein hydrolysates with desired characteristics, crucial factors consisting of pH, temperature, extraction time, solvent type, enzyme concentration and ratio-of-substrate-concentration need to be optimized. The physicochemical and functional properties of mushroom protein hydrolysates are summarized. Variability of mushroom species, extraction efficiency, enzyme selection and cost, standardization, and consumer perception which constitute challenges and limitations for production and application of mushroom protein hydrolysates are addressed. Research should be conducted to optimize extraction and hydrolysis processes and explore new mushroom species

Characterisation of buffalo (bubalus bubalis) bone gelatin extracted using acid and papain pre-treatment

Gelatin is widely regarded as one of the unique multifunctional biopolymers, with applications in a wide spectrum of industries. Porcine is the most prevalent source of gelatin since it is abundant and cheap. There have been substantial efforts to develop gelatin alternative sources to replace porcine because eating pigs and its derivatives is strictly prohibited in Halal and Kosher diets. This study focused on the effects of various acids and papain pretreatment on gelatin extractability and properties from buffalo bone. The buffalo bone was pre-conditioned with hydrochloric acid (HCl) and citric acid (0.05M and 0.025M, respectively) with and without papain prior to hot water extraction at 70C for 7h. The highest yield was found by 0.025M HCl treatment without papain (6.36%, dry basis). Meanwhile, the lowest yield was 3.8% using citric acid at 0.05M without papain. Papain at 100U/g was found to have no significant effect in HCl and citric acid pre-treatment. The physicochemical and functional properties of gelatin were determined. Gelatin treated by 0.025M citric acid without papain have the highest protein (84.4%), hydroxyproline (26.98mg/mL), gel strength (50.64g), and viscosity (11.32cP). It also had the highest emulsion activity index (9.52m2/g), emulsion stability (30.29min), foaming expansion (13.66%), foaming stability (10.64 to 12.47min), water holding capacity (11.68mL/g), and fat binding capacity (8.88mL/g). The pH values and isoelectric points of all gelatin range from (5.1 to 5.4) and (6.0 to 7.4), respectively. The low ash level of the gelatin revealed both acids to effectively removed minerals. All the extracted gelatin had a similar secondary structure. Buffalo bone gelatin has a potential to be used as an alternative source of halal gelatin productio

The Effect of Maturity and Extraction Solvents on Bioactive Compounds and Antioxidant Activity of Mulberry (Morus alba) Fruits and Leaves

Cultivation location, maturity levels, and extraction solvents could affect the bioactive compounds and biological activities of mulberry (Morus alba Linnaeus). The lack of study on Malaysia grown mulberry causes its underutilization. This study investigated the bioactive compound content and the antioxidant activity of Sabah-grown mulberry at two different maturity stages (fruits: red mature and black fully ripe; leaves: young and mature) extracted using 70% (v/v) methanol, 60% (v/v) ethanol, and 65% (v/v) acetone. Analyses showed that mulberry fruits demonstrated maturity dependent increment (except UHPLC-DAD quantification), while the leaves revealed maturity dependent reduction. Principal component analysis (PCA) displayed 65% (v/v) acetone black fully ripe fruits as the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol black fully ripe fruits contained 20.08–68.43% higher total anthocyanins. Meanwhile, the 65% (v/v) acetone and 70% (v/v) methanol red mature fruits were higher in chlorogenic acid (27.53–47.12%) and rutin (31.42–35.92%) than other fruit extracts, respectively. For leaves, 65% (v/v) acetone young leaves were the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol young leaves possessed greater chlorogenic acid (19.56–74.11%) than other leaf extracts. Overall, Malaysia-grown mulberry is rich in phenolics and antioxidants, suggesting its potential application in food and pharmaceutical products

Anthropogenic particles in the muscle, gill, and gastrointestinal tract of marine fish sold for human consumption

Contamination of marine fish with the widespread distribution of anthropogenic particles (APs) becomes increasingly severe, however, related research on the assessment of the occurrence of APs in the edible tissue of commercial fish is scarce. The objective of this study was to evaluate the features of APs pollution based on seven species of commercial marine fish (n = 12 per species) and investigate the accumulation of APs in different tissues of fish namely gill and gastrointestinal tract (GIT), and muscle. The results show that a total of 62 APs were detected in 33 out of 84 (39.3%) fresh fish samples using a micro-Raman spectrometer which in particular is characterized by a blue color, shape-like fiber, and size smaller than 0.5 mm. Among them, 47 (75.8%) particles were identified as pigments such as indigo, chrome yellow-orange, disperse yellow, and pigment black. The other 11 (17.7%) particles were plastic including polypropylene (PP), polyethylene terephthalate (PET), and polyacrylonitrile (PAN). And the rest 4 (6.5%) particles were anthropogenic cellulose fibers. Muscle tissue from six species of fish was detected to contain a total of 15 APs. Based on the total mean of APs found in fish muscle (0.018 AP items/g tissue) and on the consumption of fish in Malaysia (59 kg/capita/year), the estimated human intake of APs through fish consumption was 1062 AP items/year/capita. Considering that food consumption is an important route of human exposure to APs, it is suggested to add APs testing into the guidelines of food safety management systems and adopt mitigation measures to reduce the APs pollution in food